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  • 1.
    Ahlm, Kristin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Forensic Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Saveman, Britt-inger
    Umeå University, Faculty of Medicine, Department of Nursing. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Suicidal drowning deaths in Northern Sweden 1992-2009Manuscript (preprint) (Other academic)
  • 2.
    Alenius Dahlqvist, Jenny
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Karlsson, Marcus
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Handheld ECG in analysis of arrhythmia and heart rate variability in children with Fontan circulation2014In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 47, no 3, 374-382 p.Article in journal (Refereed)
    Abstract [en]

    Background: Our aim was to evaluate the intermittent use of a handheld ECG system for detecting silent arrhythmias and cardiac autonomic dysfunction in children with univentricular hearts. Methods: Twenty-seven patients performed intermittent ECG recordings with handheld devices during a 14-day period. A manual arrhythmia analysis was performed. We analyzed heart rate variability (HRV) using scatter plots of all interbeat intervals (Poincare plots) from the total observation period. Reference values of HRV indices were determined from Holter-ECGs in 41 healthy children. Results: One asymptomatic patient had frequent ventricular extra systoles. Another patient had episodes with supraventricular tachycardia (with concomitant palpitations). Seven patients showed reduced HRV. Conclusions: Asymptomatic arrhythmia was detected in one patient. The proposed method for pooling of intermittent recordings from handheld or similar devices may be used for detection of arrhythmias as well as for cardiac autonomic dysfunction.

  • 3.
    Alenius Dahlqvist, Jenny
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Karlsson, Marcus
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Strömvall-Larsson, Eva
    Division of Cardiology, Department of Paediatrics, Sahlgrenska University Hospital/Queen Silvia Children’s Hospital, Göteborg University, Göteborg, Sweden.
    Berggren, Håkan
    Division of Cardiothoracic Surgery, Department of Paediatrics, Sahlgrenska University Hospital/Queen Silvia Children’s Hospital, Göteborg University, Göteborg, Sweden.
    Hanseus, Katarina
    Department of Paediatrics, Children’s Hospital, Lund University Hospital, Lund, Sweden.
    Johansson, Sune
    Paediatric Cardiac Surgical Unit, Children’s Hospital, Lund University Hospital, Lund, Sweden.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Heart rate variability in children with fontan circulation: lateral tunnel and extracardiac conduit2012In: Pediatric Cardiology, ISSN 0172-0643, E-ISSN 1432-1971, Vol. 33, no 2, 307-315 p.Article in journal (Refereed)
    Abstract [en]

    The technique in Fontan surgery has developed from the lateral tunnel (LT) toward the extracardiac conduit (EC) used to reduce long-term complications such as atrial arrhythmia and sinus node dysfunction. Heart rate variability (HRV) examines cardiac nervous activity controlling the sinus node. This study aimed to investigate HRV in a cohort of children with univentricular hearts, focusing on the relation between HRV and surgical procedure. For 112 children with Fontan circulation, HRV was analyzed using power spectral analysis. Spectral power was determined in three regions: very-low-frequency (VLF), low-frequency (LF), and high-frequency (HF) regions. Patients were compared with 66 healthy controls subject. Patients with LT were compared with patients who had EC. The children with Fontan circulation showed a significantly reduced HRV including total power (P < 0.0001), VLF (P < 0.0001), LF (P < 0.0001), and HF (P = 0.001) compared with the control subjects. The LT and EC patients did not differ significantly. Reduced HRV was found in both the LT and EC patients. In terms of HRV reduction, EC was not superior to LT.

  • 4.
    Arvidsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Wikström, Gerhard
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Right ventricular involvement in transthyretin amyloidosisManuscript (preprint) (Other academic)
    Abstract [en]

    Objectives

    Right heart involvement and dysfunction is frequently encountered in cardiomyopathies. In immunoglobulin light chain (AL) amyloidosis, right ventricular (RV) function has been described as a strong determinant of survival. However, RV involvement in transthyretin related amyloidosis (ATTR) has been somewhat overlooked. We therefore sought to establish the degree of RV involvement in ATTR amyloidosis and compare the findings with sarcomeric hypertrophic cardiomyopathy (HCM).

    Patients and methods

    Forty-two patients with diagnosed ATTR and echocardiographic evidence of cardiac amyloidosis (cardiac ATTR), 19 ATTR patients with normal left ventricular (LV) wall thickness (non-cardiac ATTR), 25 patients with diagnosed sarcomeric HCM and 30 healthy controls were included in the study. Echocardiographic examinations were analysed and standard measurements of LV and RV dimensions and function were carried out. In addition, LV global and RV global and segmental strain were analysed. The degree of cardiac involvement and function was compared between non-cardiac ATTR patients and healthy controls and between cardiac ATTR patients and with those having HCM.

    Results

    Non-cardiac ATTR amyloidosis patients did not differ from healthy controls, either in geometrical or functional measurements of the LV and RV. HCM patients had significantly thicker interventricular septal thickness (p=0.017) and thinner posterior wall thickness (p=0.004) as compared to cardiac ATTR. When comparing cardiac ATTR and HCM patients by means of RV structure and function only segmental strain differed between the two patient groups. In cardiac ATTR we found an RV apex-to-base strain gradient with highest deformation in the apex whereas the pattern was inverse in patients with HCM.

    Conclusions

    RV involvement is common only in ATTR patients with concomitant LV involvement. The present study also detected an apical sparing pattern for the RV in patients with ATTR cardiomyopathy, similar to what has previously been described for the LV. This pattern was not seen in HCM patients. Further studies are warranted to assess the clinical importance of these findings.

  • 5.
    Arvidsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Pilebro, Björn
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Westermark, Per
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Amyloid Cardiomyopathy in Hereditary Transthyretin V30M Amyloidosis - Impact of Sex and Amyloid Fibril Composition2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 11, e0143456Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Transthyretin V30M (ATTR V30M) amyloidosis is a phenotypically diverse disease with symptoms ranging from predominant neuropathy to exclusive cardiac manifestations. The aims of this study were to determine the dispersion of the two types of fibrils found in Swedish ATTR V30M patients -Type A consisting of a mixture of truncated and full length ATTR fibrils and type B fibrils consisting of full length fibrils, and to estimate the severity of cardiac dysfunction in relation to fibril composition and sex.

    MATERIAL AND METHODS: Echocardiographic data were analysed in 107 Swedish ATTR V30M patients with their fibril composition determined as either type A or type B. Measurements of left ventricular (LV) dimensions and evaluation of systolic and diastolic function including speckle tracking derived strain were performed. Patients were grouped according to fibril type and sex. Multivariate linear regression was utilised to determine factors of significant impact on LV thickness.

    RESULTS: There was no significant difference in proportions of the two types of fibrils between men and women. In patients with type A fibrils, women had significantly lower median septal (p = 0.007) and posterior wall thicknesses (p = 0.010), lower median LV mass indexed to height (p = 0.008), and higher septal strain (p = 0.037), as compared to males. These differences were not apparent in patients with type B fibrils. Multiple linear regression analysis revealed that fibril type, sex and age all had significant impact on LV septal thickness.

    CONCLUSION: This study demonstrates a clear difference between sexes in the severity of amyloid heart disease in ATTR V30M amyloidosis patients. Even though type A fibrils were associated with more advanced amyloid heart disease compared to type B, women with type A fibrils generally developed less cardiac infiltration than men. The differences may explain the better outcome for liver transplanted late-onset female patients compared to males.

  • 6.
    Backman, Christer
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Johansson, Bengt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Tossavainen, Erik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Unusual arrhythmogenic myocardial disease2014In: International Cardiovascular Forum Journal, ISSN 2410-2636, Vol. 1, no 4, 195-196 p.Article in journal (Refereed)
  • 7.
    Backman, Christer
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Burned out myocardium in biventricular hypertrophic cardiomyopathy presenting with congestive heart failure: importance of ECG changes2014In: International Cardiovascular Forum Journal, ISSN 2410-2636, Vol. 1, no 3, 159-160 p.Article in journal (Refereed)
  • 8.
    Backman, Clas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Hand Surgery.
    Cold finger1993Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Post Traumatic Cold Intolerance is the most common, and often the most prominent disabilityfrom hand trauma. The discomfort caused by cold is believed to be linked to a dysfunction o f thedigital vasoregulation, but its pathophysiology is poorly understood. Cold induced vasospasm, i.e.the pathologically increased reactivity o f the digital vessels to cold, is commonly found in handsthat have sustained trauma, especially with damage to vascular and neural structures.

    This thesis is based upon a series o f clinical and laboratory studies on cold induced vasospasm andcold intolerance in 35 patients treated for digital amputation. The replanted digit was used as astudy model, since it represents a body part which at the moment o f reconstruction is devoid o f allinnervation. Replantations were performed according to two different principles o f vascularreconstruction; using long or short vessel grafts. Finger Systolic Pressure (FSP) was used as aparameter o f digital vasoregulation at different temperatures, and cold intolerance was assessedusing a logarithmic rating scale (Borg). Non-injured fingers and amputation stumps were used ascontrols. Clinical and laboratory investigations were performed at different intervals from oneweek to three years after the reconstruction.

    During the first two weeks following replantation, whole body cold exposure, or cooling o f thereplanted part to 10°C, did not cause serious spasm in the replanted vessels. Follow upinvestigations demonstrated that a cold related vasospastic tendency is established inapproximately 60% o f the replanted parts within one year after trauma. The once establishedpathologic vasoregulation, is unlikely to normalize spontaneously. Whether a cold related arterialspasticity will develop in the replanted digit or not, is not related to the surgeon's choice o ftechnique for vascular reconstruction. Cold related arterial spasticity was more common inamputation stumps than in replanted digits, Our findings suggest that there is a pathologicalreaction to cold in the distal palm vessels but the nature o f this disturbance is not clear.

    All patients developed some degree o f Post Traumatic Cold Intolerance. Approximately 60% o fthe patients stated that some improvement took place, but none o f the patients was free o f coldintolerance 1-7 years after the injury. Patients with a pathological cold induced vasospasm is likelyto present with severe cold intolerance, which indicates that the vasospasm is involved as one o fthe causes o f Post Traumatic Cold Intolerance.

  • 9.
    Bajraktari, Gani
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Left ventricular global dyssynchrony is exaggerated with age2013In: International Cardiovascular Forum, ISSN 2410-2636, Vol. 1, no 1, 47-51 p.Article in journal (Refereed)
    Abstract [en]

    Background and Aim. Total isovolumic time (t-IVT) and Tei index both reflect global left ventricular (LV) dyssynchrony. They have been shown to be sensitive in responding to myocardial revascularization and in predicting clinical outcome in heart failure patients. Since most these patients are senior, determining the exact effect of age on such parameters remains mandatory. The aim of this study was to investigate the effect of age on LV t-IVT and Tei index compared with conventional systolic and diastolic parameters in normal individuals.

    Methods. We studied 47 healthy individuals, mean age 62±12 years (24 female), who were arbitrarily classified into three groups: M (middle age), S (seniors), and E (elderly), using spectral Doppler echocardiography and tissue-Doppler imaging. We studied the interrelation between age, LV systolic and diastolic function parameters as well as t-IVT [60 – (total ejection time + total filling time) in s/min], and Tei index (T-IVT/ejection time).

    Results. LV ejection fraction was 68±6%, E/A ratio 1±0.4, filling time 538±136ms, ejection time 313±26ms, t-IVT 7.7±2.6 s/min and Tei index 0.41±0.14. Age strongly correlated with t-IVT (r=0.8, p<0.001) and with Tei index (r=0.7, p<0.001) but not with QRS duration. Age also correlated with E/A ratio (r=-0.6, p<0.001), but not with global or segmental systolic function measurements. Mean values for t-IVT were 5.5 (95% CI, 4.6-6.3 s/min) for M, 6.9 (95% CI, 6.0-7.8 s/min) for S and 9.5 (95% CI, 8.4-10.6 s/min) for E groups. The corresponding upper limit of the t-IVT 95% normal CI (calculated as mean ±2SD) for the three groups was 8.3 s/min, 10.5 s/min and 14.5 s/min, respectively. The upper limit of normal t-IVT 95% CI was significantly shorter in the S compared with the E group (p=0.001). T-IVT correlated with A wave (r=0.66, p<0.001), E/A ratio (r=-0.56, p<0.001), septal e’ (r=-0.49, p=0.001) and septal a’ (r=0.4, p=0.006), but not with QRS.

    Conclusions. In normals, age is associated with exaggerated LV global dyssynchrony and diastolic function disturbances, but systolic function remains unaffected. The strong relationship between age and t-IVT supports its potential use as a marker of global LV dyssynchrony. In addition, variations in the upper limit of normal values, particularly in the elderly may have significant clinical applications in patients recommended for CRT treatment.

  • 10.
    Berglund, Anna-Lena
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynaecology.
    Fugl-Meyer, Kerstin S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Some Sexological Characteristics of Stress Incontinent Women1996In: Scandinavian Journal of Urology and Nephrology, ISSN 0036-5599, E-ISSN 1651-2065, Vol. 30, no 3, 207-212 p.Article in journal (Refereed)
    Abstract [en]

    Forty-four women with stress urinary incontinence (SUI) were interviewed in order to investigate sexual activities, sexual function and satisfaction one month before and one year after either one of two possible surgical interventions. The findings were related to sexual response cycle, size of urinary leakage, duration of incontinence and depression. There was no significant difference in sexual activity before and after surgery. One or two sexual dysfunctions within the desire, excitement, orgasmic and resolution phases were reported by the majority both before and after intervention independently of surgical method. Neither the magnitude of the leakage nor the duration of SUI influenced the sexual experiences significantly while continence after surgery promoted sexual desire. The discrepances between the prevalence of sexual dysfunctions and the relatively high level of sexual satisfaction as well as the non-influencing parameters indicate the complexity of human sexuality.

  • 11.
    Bäckström, Torbjörn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Plasma estrogen and progesterone in relation to premenstrual tension and catamenial epilepsy1976Doctoral thesis, comprehensive summary (Other academic)
  • 12.
    Calcutteea, Avin
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Organised right ventricular remodelling in aortic stenosis even after valve replacement2013In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 168, no 2, 1549-1550 p.Article in journal (Refereed)
  • 13.
    Cameli, Matteo
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Department of Cardiovascular Diseases, University of Siena, Siena, Italy.
    Mondillo, Sergio
    Righini, Francesca Maria
    Lisi, Matteo
    Department of Cardiovascular Diseases, University of Siena, Siena, Italy.
    Dokollari, Aleksander
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Maccherini, Massimo
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Left Ventricular Deformation and Myocardial Fibrosis in Patients With Advanced Heart Failure Requiring Transplantation2016In: Journal of Cardiac Failure, ISSN 1071-9164, E-ISSN 1532-8414, Vol. 22, no 11, 901-907 p.Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To evaluate potential relationships between different components of left ventricular (LV) function and histopathological evidence for myocardial fibrosis in patients undergoing heart transplantation.

    METHODS: The study population included patients with advanced heart failure, referred for an echocardiographic examination before heart transplantation. Traditional LV function measurements and global longitudinal strain (GLS) by speckle tracking echocardiography, averaging all LV segments in 4-, 2-, and 3-chamber views were obtained in all subjects. LV tissue samples were obtained from all patients who underwent heart transplantation. Myocardial fibrosis was assessed using Masson's staining.

    RESULTS: Of 106 patients referred for cardiac transplantation, 47 underwent cardiac transplantation and were enrolled in the study. LV myocardial fibrosis and its grade strongly correlated with GLS (r = 0.75, P = .0001), modestly with global circumferential strain and LV torsion (r = 0.61, P = .001 and r = 0.52, P = .01, respectively) and weakly with mitral S' wave (r = -0.41; P = .01) and mitral annular plane systolic excursion (r = -0.35; P = .05) but did not correlate with LV ejection fraction (r = -0.12; P = NS). GLS had the strongest accuracy for detecting LV fibrosis (area under the curve, 0.92). None of the echo parameters correlated with patient's exercise capacity.

    CONCLUSION: Global longitudinal strain is the most accurate LV global function measure that correlates with the extent of myocardial fibrosis in patients with advanced systolic HF requiring heart transplantation.

  • 14. Elgzyri, Targ
    et al.
    Castenfors, Jan
    Hägg, Erik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Backman, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Thorén, Marja
    Bramnert, Margareta
    The effects of GH replacement therapy on cardiac morphology and function, exercise capacity and serum lipids in elderly patients with GH deficiency2004In: Clinical Endocrinology, ISSN 0300-0664, E-ISSN 1365-2265, Vol. 61, no 1, 113-122 p.Article in journal (Refereed)
    Abstract [en]

    Objectives:  To assess effects of GH replacement therapy on cardiac structure and function, exercise capacity as well as serum lipids in elderly patients with GH deficiency (GHD).

    Patients and methods:  Thirty-one patients (six females, 25 males), aged 60–79 years (mean 68 years) with GHD on stable cortisone and thyroxine substitution were studied. All men with gonadotropin deficiency had testosterone and one woman had oestrogen replacement. They were randomized in a double-blind manner to GH or placebo treatment for 6 months, followed by another 12 months GH (Humatrope, Eli Lilly & Co, Uppsala, Sweden). GH dose was 0·017 mg/kg/week for 1 month and then 0·033 mg/kg/week divided into daily subcutaneous injections at bedtime. Echocardiography, exercise capacity tests and serum lipid measurements were performed at 0, 6, 12 and 18 months.

    Results:  During the 6-month placebo-controlled period there were no significant changes in the placebo group, but in the GH-treated group there was a significant increase in IGF-I to normal levels for age, with median IGF-I from 6·9 to 18·5 nmol/l, increase in resting heart rate and maximal working capacity. During the open GH study, IGF-I increased from 8·7 to 19·2 nmol/l at 6 months and 18·8 nmol/l at 12 months (P ≤ 0·001). At 6 months, in the open GH study group, a minor decrease in aortic outflow tract integral (VTI) from 21·8 to 20·7 cm (P = 0·031) and an increase in heart rate at rest from 63 to 67 bpm (P = 0·017), heart rate at maximum exercise from 138 to 144 bpm (P = 0·005) and maximum load at exercise from 142 to 151 Watts (P = 0·014) were seen. These changes were temporary and returned at 12 months with no significant difference from baseline values. Left ventricular dimensions and blood pressure showed no significant changes. At 6 months, in the open GH study group, there was a significant decrease in serum low-density lipoprotein (LDL) cholesterol from 3·7 to 3·4 mmol/l (P = 0·006), a decrease in LDL/HDL ratio from 3·4 to 3·1 (P = 0·036) and a decrease in serum total cholesterol from 5·6 to 5·3 mmol/l (P = 0·036). At 12 months, serum lipids showed same changes with a significant decrease in serum LDL cholesterol (P = 0·0008), in LDL/HDL ratio (P = 0·0005) and in serum total cholesterol (P = 0·049). Serum HDL cholesterol showed no significant change at 6 months, at 12 months a significant increase was seen from 1·2 to 1·4 mmol/l (P = 0·007). There were no significant changes in serum triglycerides.

    Conclusions:  GH substitution to elderly patients with GHD caused only a transient increase in heart rate. At the end of the 12 months there were no significant changes on cardiac noninvasive structural and functional parameters. Maximal working capacity transiently improved. Thus, the therapy was safe without negative effects on cardiac structural and functional noninvasive parameters. Lipid profiles improved with reduction of serum LDL cholesterol accompanied by significant improvement of LDL/HDL ratio and serum HDL cholesterol after 12 months treatment.

  • 15.
    Engvall, Christer
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Can myocardial strain differentiate hypertrophic from infiltrative etiology of a thickened septum?2011In: Echocardiography, ISSN 0742-2822, E-ISSN 1540-8175, Vol. 28, no 4, 408-415 p.Article in journal (Refereed)
    Abstract [en]

    Septal systolic strain measurements showed reduced longitudinal function but its localized nature failed to demonstrate radial disturbances in patients with pathologically thickened septum. No difference was found in systolic strain between patients according to the etiology of septal thickness. This limitation might be either technical or is explained by the maintained radial function in all patient groups.

  • 16.
    Flodgren, Gerd
    et al.
    Centre for Musculoskeletal Research, University of Gävle, Sweden.
    Crenshaw, AG
    Centre for Musculoskeletal Research, University of Gävle, Sweden.
    Gref, Margareta
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Fahlström, Martin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine.
    Changes in interstitial noradrenaline, trapezius muscle activity and oxygen saturation during low-load work and recovery2009In: European Journal of Applied Physiology, ISSN 1439-6319, E-ISSN 1439-6327, Vol. 107, no 1, 31-42 p.Article in journal (Refereed)
    Abstract [en]

    Both physical as well as mental demands result in an increased activity in the sympathetic nervous system (SNS) with changes in blood-pressure and heart-rate. Through local release of catecholamines, e.g. noradrenaline (NAd) SNS exerts various actions at the muscle level. The aims of this study were to investigate the effects of low-load repetitive work alone and in combination with mental demands on local muscle interstitial noradrenaline concentration [NAd]i, muscle activity and oxygenation, assessed with microdialysis, surface electromyography, and near-infrared spectroscopy, respectively. Healthy females (n = 15) were exposed to (1) 30 min repetitive work (RW) and (2) 30 min repetitive work with superimposed mental load (RWML) on two different occasions. Muscle [NAd]i and muscle activity increased significantly in response to RW, but did not increase further during RWML. For RW, [NAd]i was found to be inversely correlated to muscle activity. Oxygenation decreased significantly during work, independently of occasion. Our findings indicate that low-load work causes significantly increased trapezius muscle [NAd]i in healthy females, and short periods of superimposed mental load do not add to this increase and further, that both muscle activity and oxygenation were unaffected by the superimposed mental load.

  • 17.
    Gref, Margareta
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Formler för enprovs plasmaclearance2000In: Njurarna och övre urinvägarna / [ed] Göran Granerus, Lund: Studentlitteratur , 2000, 57-64 p.Chapter in book (Other academic)
  • 18.
    Gref, Margareta
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Glomerular filtration rate in adults: a single sample plasma clearance method based on the mean sojurn time2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Glomerular filtration rate (GFR) is a key parameter in evaluating kidney function. After a bolus injection of an exogenous GFR marker in plasma an accurate determination of GFR can be made by measuring the marker concentration in plasma during the excretion. Simplified methods have been developed to reduce the number of plasma samples needed and yet still maintain a high accuracy in the GFR determination. Groth previously developed a single sample GFR method based on the mean sojourn time of a GFR marker in its distribution volume. This method applied in adults using the marker 99m Tc-DTPA is recommended for use when GFR is estimated to be ≥ 30 mL/min. The aim of the present study was to further develop the single plasma sample GFR method by Groth including patients with severely reduced renal function and different GFR markers. Three different GFR markers 51Cr-EDTA, 99mTc-DTPA and iohexol were investigated. Formulas were derived for the markers 51Cr-EDTA and iohexol when GFR is estimated to be ≥ 30 mL/min. For patients with an estimated GFR < 30 mL/min a special low clearance formula with a single sample obtained about 24 h after marker injection was developed. The low clearance formula was proven valid for use with all three markers. The sources of errors and their influence on the calculated single sample clearance were investigated. The estimated distribution volume is the major source of error but its influence can be reduced by choosing a suitable sampling time. The optimal time depends on the level of GFR; the lower GFR the later the single sample should be obtained. For practical purpose a 270 min sample is recommended when estimated GFR ≥ 30 mL/min and a 24 h sample when estimated GFR < 30 mL/min. Sampling at 180 min after marker injection may be considered if GFR is estimated to be essentially normal.

  • 19.
    Gref, Margareta
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Karp, Kjell
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    99mTc-diethylenetriamine penta-acetate plasma clearance in advanced renal failure by the mean sojourn time approach2009In: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 30, no 3, 202-205 p.Article in journal (Refereed)
    Abstract [en]

    Objectives: The single-sample 99mTc-diethylenetriamine penta-acetate (DTPA) clearance method by Christensen and Groth is recommended by the Radionuclides in Nephrourology Committee on Renal Clearance for use in adults with an estimated glomerular filtration rate (GFR) ≥30 ml/min. The purpose of this study was to test a new 99mTc-DTPA single-sample low clearance formula for GFR lesser than 30 ml/min.

    Methods: Twenty-one adult patients (29 investigations) were included. Reference clearance was calculated with both 51Cr-EDTA and 99mTc-DTPA according to Brøchner-Mortensen with samples drawn between 3 and 24 h. Single-sample clearance was calculated from a 24 h sample using the low clearance formula

    Equation (Uncited)Image Tools

    C(t) is the activity of the tracer in the plasma sample t minutes after the injection and Q0 is the injected amount. ECV is the extracellular volume in ml defined as the distribution volume of the tracer. ECV is estimated from the body surface area as ECV=8116.6×body surface area-28.2.

    Results: The mean difference between reference and 99mTc-DTPA single-sample clearance was -0.5 ml/min (SD 1.0 ml/min) for 99mTc-DTPA and -0.8 ml/min (SD 1.2 ml/min) for 51Cr-EDTA as reference clearance.

    Conclusion: In adult patients it is possible, even with GFR lesser than 30 ml/min, to get an accurate determination of 99mTc-DTPA plasma clearance from a single sample using the mean sojourn time approach. The blood sample should be obtained about 24 h after injection of the GFR tracer.

  • 20.
    Gref, Margareta
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Karp, Kjell
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    GFR determination in adults with a single-sample iohexol plasma clearance method based on the mean sojourn time2007In: Nephrology, Dialysis and Transplantation, ISSN 0931-0509, E-ISSN 1460-2385, Vol. 22, no 11, 3166-3173 p.Article in journal (Refereed)
    Abstract [en]

    Background. Glomerular filtration rate is a key parameter in kidney disease. The Radionuclides in Nephrourology Committee has recommended a single-sample method with 99mTc-DTPA based on the mean sojourn time. This study was done to develop the method for use with iohexol making the method more available.

    Methods. The single-sample formula was derived for group I (n = 48, Cl = 8–188 ml/min) and applied on group II (n = 47) and on group III (n = 123). In groups I and II, reference clearance was determined according to Sapirstein and in group III according to Brøchner-Mortensen.

    Results. The formula (a = (−6.49 × 10−6×t + 8.85 × 10−4)×t, b = 1.143 × t and c = ln[(C(t))×(ECV/Q0)](ECV) was derived for patients with estimated Cl > 30 ml/min with the best result if the single sample was obtained between 4 and 5 h. Extracellular volume was estimated as ECV =9985 × BSA − 3431.

    The formula ClS(24 h) = −ln[(C(t))×(ECV/Q0)](ECV)/(t) was developed for patients with estimated Cl <30 ml/min with a single sample at 24 h. With this combined approach SDdiff was 2.7 ml/min in group II and 3.1 ml/min in group III.

    Conclusions. An accurate determination of iohexol clearance can be obtained from a single plasma sample applying the mean sojourn time approach. A separate formula must be used for patients with low clearance values. Body surface area (BSA), injected amount of iohexol (Q0), time when the single sample is drawn (t) and the concentration of iohexol [C(t)] in the sample are needed for the calculations.

  • 21.
    Gref, Margaretha
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Karp, Kjell
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Single-sample 99mTc-diethylenetriamine penta-acetate plasma clearance in advances renal failure by the mean sojourn time approach2009In: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 30, no 3, 202-205 p.Article in journal (Refereed)
    Abstract [en]

    AB Objectives: The single-sample 99mTc-diethylenetriamine penta-acetate (DTPA) clearance method by Christensen and Groth is recommended by the Radionuclides in Nephrourology Committee on Renal Clearance for use in adults with an estimated glomerular filtration rate (GFR) >=30 ml/min. The purpose of this study was to test a new 99mTc-DTPA single-sample low clearance formula for GFR lesser than 30 ml/min. Methods: Twenty-one adult patients (29 investigations) were included. Reference clearance was calculated with both 51Cr-EDTA and 99mTc-DTPA according to Brochner-Mortensen with samples drawn between 3 and 24 h. Single-sample clearance was calculated from a 24 h sample using the low clearance formula C(t) is the activity of the tracer in the plasma sample t minutes after the injection and Q0 is the injected amount. ECV is the extracellular volume in ml defined as the distribution volume of the tracer. ECV is estimated from the body surface area as ECV=8116.6xbody surface area-28.2. Results: The mean difference between reference and 99mTc-DTPA single-sample clearance was -0.5 ml/min (SD 1.0 ml/min) for 99mTc-DTPA and -0.8 ml/min (SD 1.2 ml/min) for 51Cr-EDTA as reference clearance. Conclusion: In adult patients it is possible, even with GFR lesser than 30 ml/min, to get an accurate determination of 99mTc-DTPA plasma clearance from a single sample using the mean sojourn time approach. The blood sample should be obtained about 24 h after injection of the GFR tracer.

  • 22.
    Grönlund, Christer
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Albano, Amanda
    Gustavsson, Sandra
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Wiklund, Urban
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Significant beat-to-beat variability of E/e’ irrespective of respiration2013In: International cardiovascular forum, ISSN 2409-3424, Vol. 1, no 2, 88-89 p.Article in journal (Refereed)
    Abstract [en]

    The E/e’ ratio is commonly used in Doppler echocardiographic examinations to estimate the pulmonary capillary wedge pressure. The rationale of using this ratio is to combine left ventricular (LV) filling (E) and relaxation (e’) velocities to indirectly assess left atrial pressure. However, the accuracy of this index has recently been questioned, particularly in patients with controlled heart failure. Likewise, the potential beat-to-beat variability of such measurements remains undetermined. The cardiovascular system is subject to several oscillations with the potential of influencing LV function and its intra-cavitary pressures, hence measurements of its filling and relaxation velocities. The aim of this pilot study was to assess the beat-to-beat variability of the E/e’ ratio in one minute long examination in healthy subjects, and patients with various severity of amyloid heart disease. The results show that despite critical application of the standard echocardiographic recording recommendations, E/e’ beat-to-beat variability was 36 % (22 to 50%) in healthy subjects and 17 % (11-26%) in patients, and where the most severe amyloid heart disease had the least variability. Thus, clinical use of a single or few cardiac beats might not necessarily reflect an accurate ratio between the two velocities, and hence casts doubt over their diagnostic value.

  • 23.
    Gustafsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Grönlund, Christer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Suhr, Ole B.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Discriminating hereditary transthyretin cardiomyopathy from hypertrophic cardiomyopathy using an echocardiographic and ECG based classification tree2014In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 35, no Supplement 1, Meeting abstract P5254, 929-929 p.Article in journal (Other academic)
  • 24.
    Gustafsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Umeå Heart Centre.
    Grönlund, Christer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Umeå Heart Centre.
    Suhr, Ole
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå Heart Centre.
    Can echocardiography differentiate hereditary transthyretin amyloidosis from hypertrophic cardiomyopathy?2013In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 34, no Supplement: 1, 213-213 p.Article in journal (Other academic)
    Abstract [en]

    Purpose: Hereditary transthyretin amyloidosis (ATTR) andhypertrophic cardiomyopathy (HCM) have many phenotypic similarities when examined by echocardiography. As the two conditions have different treatment strategies it is of importance to accurately diagnose these patients early in the disease. This study aimed to identify the most accurate echocardiographic method in differentiating these two conditions by using traditional and speckle tracking echocardiographyas well as myocardial texture analysis.

    Methods: We investigated 40 healthy controls, 33 patients with biopsy proven ATTR and 20 with HCM. All patients had septal thickness >12 mm. We measured left ventricular (LV) global strain as intrinsic systolic function and LV E/e' to estimate filling pressures. We also tested septal cyclic integrated backscatter (cIBS) and septal entropy as both being measures for myocardial highly reflection pattern whereas cIBS showing motion of highly reflective echoes and entropy the distribution of highly reflective echoes.

    Results: LV global strain, cIBS and E/e' were not useful in differentiating ATTR from HCM. However, septal entropy was found to be significantly different and showed an area under the curve from ROC analysis of 0.66 separating ATTR from HCM.

    Conclusion: After using detailed analysis of different aspects of LV morphology and function we found that myocardial texture behavior from entropy analysis was the only method useful in differentiating patients with ATTR fromHCM.

  • 25.
    Gustavsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Granåsen, Gabriel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Grönlund, Christer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences. Umeå University, Faculty of Science and Technology, Centre for Biomedical Engineering and Physics (CMTF).
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Can echocardiography and ECG discriminate hereditary transthyretin V30M amyloidosis from hypertrophic cardiomyopathy?2015In: Amyloid: Journal of Protein Folding Disorders, ISSN 1350-6129, E-ISSN 1744-2818, Vol. 22, no 3, 163-170 p.Article in journal (Refereed)
    Abstract [en]

    Objective: Hereditary transthyretin (ATTR) amyloidosis with increased left ventricular wall thickness could easily be misdiagnosed by echocardiography as hypertrophic cardiomyopathy (HCM). Our aim was to create a diagnostic tool based on echocardiography and ECG that could optimise identification of ATTR amyloidosis. Methods: Data were analysed from 33 patients with biopsy proven ATTR amyloidosis and 30 patients with diagnosed HCM. Conventional features from ECG were acquired as well as two dimensional and Doppler echocardiography, speckle tracking derived strain and tissue characterisation analysis. Classification trees were used to select the most important variables for differentiation between ATTR amyloidosis and HCM. Results: The best classification was obtained using both ECG and echocardiographic features, where a QRS voltage >30 mm was diagnostic for HCM, whereas in patients with QRS voltage <30 mm, an interventricular septal/posterior wall thickness ratio (IVSt/PWt) >1.6 was consistent with HCM and a ratio <1.6 supported the diagnosis of ATTR amyloidosis. This classification presented both high sensitivity (0.939) and specificity (0.833). Conclusion: Our study proposes an easily interpretable classification method for the differentiation between HCM and increased left ventricular myocardial thickness due to ATTR amyloidosis. Our combined echocardiographic and ECG model could increase the ability to identify ATTR cardiac amyloidosis in clinical practice.

  • 26.
    Gustavsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Pilebro, Björn
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Westermark, P.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Suhr, Ole B.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Gender related differences in cardiac function in patients with hereditary transthyretin amyloidosis2015In: European Journal of Heart Failure, ISSN 1388-9842, E-ISSN 1879-0844, Vol. 17, 64-65 p.Article in journal (Other academic)
  • 27.
    Hagström, Linn
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Karp, Kjell
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Waldenström, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Impact of age and sex on normal left heart structure and function2016In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097XArticle in journal (Refereed)
    Abstract [en]

    BACKGROUND: Accurate age- and sex-related normal reference values of ventricular structure and function are important to determine the level of dysfunction in patients. The aim of this study therefore was to document normal age range sex-related measurements of LV structural and functional measurements to serve such purpose.

    METHODS: We evaluated left ventricular structure and function in 293 healthy subjects between 20 and 90 years with equally distributed gender. Doppler echocardiography was used including measure of both systolic and diastolic functions.

    RESULTS: Due to systolic LV function, only long axis function correlated with age (r = 0·55, P<0·01) and the correlation was stronger in females. Concerning diastolic function, there was a strong age correlation in all parameters used (r = 0·40-0·74, P<0·001). Due to LV structural changes over age, females showed a larger reduction in end-diastolic volumes, but no or trivial difference in wall thickness after the age of 60 years.

    CONCLUSION: Age is associated with significant normal changes in left ventricular structure and function, which should be considered when deciding on normality. These changes are related to systemic arterial changes as well as body stature, thus reflecting overall body ageing process. Furthermore, normal cardiac ageing in females might partly explain the higher prevalence of heart failure with preserved ejection in females.

  • 28.
    Hedelin, R
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bjerle, P
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henriksson-Larsén, Karin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Heart rate variability in athletes: relationship with central and peripheral performance.2001In: Medicine & Science in Sports & Exercise, ISSN 0195-9131, E-ISSN 1530-0315, Vol. 33, no 8, 1394-1398 p.Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To investigate relationships between heart rate variability (HRV) and peripheral and central performance measures, 17 cross-country (X-C) skiers and seven canoeists were studied before and after a training period of 7 months. METHODS: For the skiers and canoeists respectively, leg and arm peak torque (Tq), time to peak torque (TiTq), and total work (Wrk) were measured in an isokinetic dynamometer. Maximal oxygen uptakes (VO(2max)) were obtained from treadmill tests. Power spectral analysis of HRV was performed on electrocardiographic recordings in the resting supine position and after a tilt to yield power in the low-frequency (0.04--0.15 Hz) and high-frequency (0.15--0.45 Hz) components of HRV. RESULTS: The change in normalized LF-variability in standing (Delta LFnT) correlated (P < 0.01) with the changes in TiTq (r = 0.63), max lactate (r = -0.63), and VO(2max) (r = -0.53). The change in absolute LFT was inversely correlated with the change in Tq. Subjects who improved VO(2max) were characterized by consistently higher high-frequency and total HRV than subjects with deteriorated aerobic capacity (P < 0.05). CONCLUSION: The results suggest that improved measures of both peripheral and central (aerobic) work capacities were associated with a reduction of low-frequency HRV in the tilted position. High-frequency and total HRV did not change in proportion with changes in muscle performance or aerobic capacity, but the ability to further improve VO(2max) with training in these already fit subjects seemed to depend on their average levels of these HRV measures, interpreted to reflect parasympathetic activity.

  • 29.
    Hedelin, R
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Wiklund, U
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Bjerle, P
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henriksson-Larsén, K
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Pre- and post-season heart rate variability in adolescent cross-country skiers.2000In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 10, no 5, 298-303 p.Article in journal (Refereed)
    Abstract [en]

    To investigate the effects on cardiac autonomic control after a competitive cross-country skiing season, 9 females and 8 males, 16-19 years old, performed tilt-table heart rate variability (HRV) recordings and incremental treadmill tests before (August), and after (April the following year) the most intensive period of training and competition. Spectral analysis of HRV showed increased total variability at rest and reduced low frequency variability in the tilted position (LFtilt) at the second test (P<0.05). The female subgroup showed consistently higher high frequency (HF) and total heart rate variability than males. Total run time (RunT) increased from 18.5+/-1.9 min to 19.4+/-1.7 min (mean+/-SD) in the entire group (P<0.05), while VO2max only showed a non-significant increase (0.05

    <0.10). Submaximal heart rates (HRsubm) were reduced by an average of 4 beats (P<0.01) but maximal HR was unchanged. Performance data suggest a positive training effect. Following training, the increased total HRV the reduced LFtilt (both at rest), and the lower submaximal heart rates indicate an altered control of heart rate both at rest and during exercise. The consistently higher HF and total variability in the females indicate an increased parasympathetic activity in females compared with males.

  • 30.
    Hedelin, Rikard
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Kenttä, Göran
    Wiklund, Urban
    Bjerle, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henriksson-Larsén, Karin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Short-term overtraining: effects on performance, circulatory responses, and heart rate variability.2000In: Medicine & Science in Sports & Exercise, ISSN 0195-9131, E-ISSN 1530-0315, Vol. 32, no 8, 1480-1484 p.Article in journal (Refereed)
    Abstract [en]

    PURPOSE AND METHODS: Nine elite canoeists were investigated concerning changes in performance, heart rate variability (HRV), and blood-chemical parameters over a 6-d training camp. The training regimen consisted of cross-country skiing and strength training, in total 13.0+/-1.6 h, corresponding to a 50% increase in training load. RESULTS: Time to exhaustion (RunT) decreased from 19.1+/-1.0 to 18.0+/-1.2 min (P < 0.05). VO2max and max lactate (La(max)) both decreased significantly (P < 0.05) over the training period (4.99+/-0.97 to 4.74+/-0.98 L x min(-1) and from 10.08+/-1.25 to 8.98+/-1.03 mmol x L(-1) respectively). Heart rates (HR) decreased significantly at all workloads. Plasma volume increased by 7+/-7% (P < 0.05). Resting cortisol, decreased from 677+/-244 to 492+/-222 nmol x L(-1) (P < 0.05), whereas resting levels of adrenaline and noradrenaline remained unchanged. The change between tests in RunT correlated significantly with the change in HRmax (r = 0.79; P = 0.01). There were no group changes in high or low frequency HRV, neither at rest nor following a tilt. CONCLUSIONS: The reduced maximal performance indicates a state of fatigue/overreaching and peripheral factors are suggested to limit performance even though HRmax and La(max) both were reduced. The reduced submaximal heart rates are probably a result of increased plasma volume. HRV in this group didn't seem to be affected by short-term overtraining.

  • 31.
    Hedelin, Rikard
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Bjerle, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henriksson-Larsén, K
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Cardiac autonomic imbalance in an overtrained athlete.2000In: Medicine & Science in Sports & Exercise, ISSN 0195-9131, E-ISSN 1530-0315, Vol. 32, no 9, 1531-1533 p.Article in journal (Refereed)
    Abstract [en]

    PURPOSE: In order to investigate overtraining-related adaptations in the autonomic nervous system, cardiac autonomic activity was examined in a junior cross-country skier who presented with reduced performance in competitions, early breathlessness during training sessions, and accumulated central fatigue. METHODS: Power spectral analysis of heart rate variability (HRV) was performed before, when overtrained (OT), and after recovery (Rec). RESULTS: In the overtrained state, high frequency (HF) and total powers in the lying position were higher compared with before and after. In normalized units, the increased HF in OT was even more prominent and clearly higher than in any control subject, and it was reversed in Rec. Resting heart rate was slightly reduced in OT and returned to baseline in Rec. CONCLUSIONS: The shift toward increased heart rate variability, particularly in the HF range, together with a reduced resting heart rate suggest a cardiac autonomic imbalance with extensive parasympathetic modulation in this athlete when overtrained.

  • 32.
    Heldestad, Victoria
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Obayashi, Konen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Nordh, Erik
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Comparison of quantitative sensory testing and heart rate variability in Swedish Val30Met ATTR2011In: Amyloid: Journal of Protein Folding Disorders, ISSN 1350-6129, Vol. 18, no 4, 183-190 p.Article in journal (Refereed)
    Abstract [en]

    Patients with transthyretin amyloidosis (ATTR) polyneuropathy, a hereditary fatal disease, often report defects in both thermal perception and autonomic nervous system function as their first clinical symptoms. While elevated thermal perception thresholds (TPT) for cold and warmth only recently have been shown as an early marker of small nerve fiber dysfunction in these patients, heart rate variability (HRV) has frequently been used to quantify autonomic neuropathy. The main purpose with this report was to elucidate a possible relationship between estimates of HRV and TPT in a selected group of early and late-onset Swedish Val30Met ATTR patients. The results show significantly more pronounced elevation of TPT in early compared to late-onset patients. Significant correlations between HRV and TPT were found among late-onset cases, indicating a possible relationship between loss of thin nerve fibers in somatic and autonomic nerves, while generally no such relationships were found among early-onset cases. This observation emphasizes the importance of testing both HRV and TPT to ensure optimal early detection of neuropathic changes in an as wide as possible range of small nerve fibers in suspected ATTR patients. This is of particular importance as the phenotype of the ATTR disease varies between groups with different age of onset.

  • 33.
    Hellström, Monica
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Backman, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Innocent left ventricular outflow tract membrane.2011In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 15, no 150(2), e65-e66 p.Article in journal (Refereed)
    Abstract [en]

    Innocent left ventricular outflow tract membranes are rare finding, and may have no significant haemodynamic effect. Thanks to the high resolution of the recent echocardiographs these membranes can be seen in detail. Various shapes and forms of such membranes need to be adequately studied and documented.

  • 34.
    Hendrikx, Tijn
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Rosenqvist, Mårten
    Sandström, Herbert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Screening for atrial fibrillation with baseline and intermittent ECG recording in an out-of-hospital population2013In: BMC Cardiovascular Disorders, ISSN 1471-2261, Vol. 13, no 1, 41- p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: the objective of this study is to investigate the detection rate of undiagnosed atrial fibrillation (AF) with short intermittent ECG recordings during four weeks among out-of-hospital patients, having at least one additional risk factor (CHADS2) for stroke.

    METHOD: Design: Cross-sectional study. Setting: Eight family practice centres and two hospital-based out-patient clinics in Sweden. Subjects: 989 out-of-hospital patients, without known AF, having one or more risk factors associated with stroke (CHADS2). Interventions: All individuals were asked to perform 10-second handheld ECG recordings during 28 days, twice daily and when having palpitations. Main outcome measures: Episodes of AF on handheld ECG recordings were defined as irregular supraventricular extrasystoles in series with a duration of 10 seconds.

    RESULTS: 928 patients completed registration. AF was found in 35 of 928 patients; 3.8% (95% confidence interval [CI] 2.7--5.2). These 35 patients had a mean age of 70.7 years (SD +/- 7.7; range 53--85) and a median CHADS2 of 2 (range 1--4). CONCLUSIONS: Intermittent handheld ECG recording over a four week period had a detection rate of 3.8% newly diagnosed AF, in a population of 928 out-of-hospital patients having at least one additional risk factor for stroke. Intermittent handheld ECG registration is a feasible method to detect AF in patients with an increased risk of stroke in whom oral anticoagulation (OAC) treatment is indicated.

  • 35.
    Hendrikx, Tijn
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Mårten, Rosenqvist
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Sandström, Herbert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Screening for atrial fibrillation in patients with left atrial enlargementIn: Article in journal (Other academic)
  • 36.
    Hendrikx, Tijn
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Rosenqvist, Mårten
    Department of Clinical Sciences, Danderyds Sjukhus, Karolinska Institutet, SE-182 88 Stockholm, Sweden.
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Sandström, Herbert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Intermittent short ECG recording is more effective than 24-hour Holter ECG in detection of arrhythmias2014In: BMC Cardiovascular Disorders, ISSN 1471-2261, Vol. 14, 41- p.Article in journal (Refereed)
    Abstract [en]

    Background: Many patients report symptoms of palpitations or dizziness/presyncope. These patients are often referred for 24-hour Holter ECG, although the sensitivity for detecting relevant arrhythmias is comparatively low. Intermittent short ECG recording over a longer time period might be a convenient and more sensitive alternative. The objective of this study is to compare the efficacy of 24-hour Holter ECG with intermittent short ECG recording over four weeks to detect relevant arrhythmias in patients with palpitations or dizziness/presyncope.

    Methods:

    Design: prospective, observational, cross-sectional study. Setting: Clinical Physiology, University Hospital. Patients: 108 consecutive patients referred for ambiguous palpitations or dizziness/presyncope.

    Interventions: All individuals underwent a 24-hour Holter ECG and additionally registered 30-second handheld ECG (Zenicor EKG ((R)) thumb) recordings at home, twice daily and when having cardiac symptoms, during 28 days.

    Main outcome measures: Significant arrhythmias: atrial fibrillation (AF), paroxysmal supraventricular tachycardia (PSVT), atrioventricular (AV) block II-III, sinus arrest (SA), wide complex tachycardia (WCT).

    Results: 95 patients, 42 men and 53 women with a mean age of 54.1 years, completed registrations. Analysis of Holter registrations showed atrial fibrillation (AF) in two patients and atrioventricular (AV) block II in one patient (= 3.2% relevant arrhythmias [95% CI 1.1-8.9]). Intermittent handheld ECG detected nine patients with AF, three with paroxysmal supraventricular tachycardia (PSVT) and one with AV-block-II (= 13.7% relevant arrhythmias [95% CI 8.2-22.0]). There was a significant difference between the two methods in favour of intermittent ECG with regard to the ability to detect relevant arrhythmias (P = 0.0094). With Holter ECG, no symptoms were registered during any of the detected arrhythmias. With intermittent ECG, symptoms were registered during half of the arrhythmia episodes.

    Conclusions: Intermittent short ECG recording during four weeks is more effective in detecting AF and PSVT in patients with ambiguous symptoms arousing suspicions of arrhythmia than 24-hour Holter ECG.

  • 37.
    Hendrikx, Tijn
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sundqvist, Martin
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Sandström, Herbert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sahlin, Carin
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Rohani, Morteza
    Al-Khalili, Faris
    Blomberg, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Rosenqvist, Mårten
    Franklin, Karl A
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Atrial fibrillation in patients with sleep apneaManuscript (preprint) (Other academic)
  • 38.
    Hendrikx, Tijn
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sundqvist, Martin
    Sandström, Herbert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sahlin, Carin
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Rohani, Morteza
    Al-Khalili, Faris
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Blomberg, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Rosenqvist, Mårten
    Franklin, Karl A
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Atrial fibrillation among patients under investigation for suspected obstructive sleep apnea2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 2, e0171575Article in journal (Refereed)
    Abstract [en]

    STUDY OBJECTIVES: Obstructive sleep apnea is common among patients with atrial fibrillation, but the prevalence and risk factors for atrial fibrillation among patients who are being investigated on suspicion of sleep apnea are not well known. The aim of the study was to estimate the prevalence of atrial fibrillation among patients investigated for suspected obstructive sleep apnea and to identify risk factors for atrial fibrillation among them.

    METHODS: The prevalence of atrial fibrillation was investigated among 201 patients referred for suspected obstructive sleep apnea. Patients without known atrial fibrillation were investigated with a standard 12-lead ECG at hospital and short intermittent handheld ECG recordings at home, during 14 days.

    RESULTS: Atrial fibrillation occurred in 13 of 201 subjects (6.5%), and in 12 of 61 men aged 60 years and older (20%). The prevalence of atrial fibrillation increased with sleep apnea severity (p = 0.038). All patients with atrial fibrillation were men and all had sleep apnea. Age 60 or older, the occurrence of central sleep apnea and diabetes mellitus were independent risk factors for atrial fibrillation after adjustments for body mass index, gender, sleep apnea and cardiovascular disease.

    CONCLUSIONS: Atrial fibrillation is common among subjects referred for sleep apnea investigation and the prevalence of atrial fibrillation increases with sleep apnea severity. Independent risk factors for atrial fibrillation among patients investigated for suspected obstructive sleep apnea include the occurrence of coexisting central sleep apnea, age 60 years or older and diabetes mellitus.

  • 39.
    Henein, Mark
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Tossavainen, Erik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Söderberg, Stefan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Grönlund, Christer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Gonzalez, Manuel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Left atrial strain rate estimates PCWP2013In: International cardiovascular forum, ISSN 2409-3424, no 1, 25-30 p.Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Raised left atrial (LA) pressure is a common pathway for many pathologies and is known for its complications. It has a direct effect on LA cavity size and potentially also its function. We hypothesized that raised LA pressure, as shown by pulmonary capillary wedge pressure (PCWP), correlates with severity of global LA deformation abnormalities during atrial systole (LASRa). DESIGN AND PATIENTS: We prospectively studied 46 consecutive patients, mean age 61 ±13 years, 17 males, of various etiologies who underwent right heart catheterization and simultaneous Doppler echocardiography using spectral, tissue Doppler and speckle tracking echocardiography techniques for assessing LA structure and function. RESULTS: PCWP correlated with direct measurements of LA structure and function: LA volume (r= 0.43, p<0.01) and LASRa (r=0.79, p<0.001). PCWP correlated also with other indirect measures of LA pressure such as E/A (r=0.65, p<0.001), E wave deceleration time (r=0.54, p<0.001), E/e’ (r=0.49, p<0.001) and LA systolic filling fraction (r=0.52, p<0.001). However, LASRa together with LA systolic filling fraction, had the highest areas under the curve (0.83 and 0.87, respectively) for identifying patients with PCWP > 15 mmHg. CONCLUSION: PCWP correlates with LA deformation rate during atrial systole and to a higher extent than conventional Doppler measures of raised LA pressures. These findings should have significant clinical implications in correctly identifying breathless patients due to raised LA pressure.

  • 40.
    Henein, Mark
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Zhao, Ying
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Disturbed left atrial mechanical function in paroxysmal atrial fibrillation: a speckle tracking study2012In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 155, no 3, 437-441 p.Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: We aimed to assess left atrial (LA) intrinsic myocardial function and its relationship to left ventricular (LV) filling pattern in a group of paroxysmal atrial fibrillation (PAF) patients.

    METHODS: Twenty-three PAF patients (age 68±7year, 10 males) were studied using speckle tracking echocardiography and compared with 18 age and sex matched controls. LA segmental longitudinal strain (S), strain rate (SR) and myocardial velocities during atrial systole were measured as were LA diameters. E/A and E/Em were also measured.

    RESULTS: LA longitudinal diameter was larger in patients (5.5±0.6 vs. 4.8±0.6cm, p<0.01) and global LA S (-9.2±4.3 vs. -12.9±4.6%, p=0.01) and SR (-1.1±0.5 vs. -1.6±0.7 1/s, p<0.01) were reduced and correlated with E/A (r=0.52, p=0.01 and r=0.43, p<0.05, respectively). LA lateral S and SR were uniformly reduced compared with controls (p<0.05 for all). Both septal and lateral wall SR correlated with E/A (p<0.05 for all), only septal S correlated with E/A (p<0.05). LA myocardial velocities were highest at the annular level and lowest at the rear in both patients and controls (p<0.01 for all).

    CONCLUSION: In PAF patients, LA systolic function is suppressed and is directly related to the pattern of LV filling which itself may suggest raised pressures. While intrinsic global and segmental function can reproducibly be studied by S and SR, myocardial velocities reflect only regional motion, thus less sensitive in demonstrating localize dysfunction.

  • 41.
    Henein, Michael
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Arvidsson, Sandra
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Pilebro, Björn
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Backman, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Long mitral valve leaflets determine left ventricular outflow tract obstruction during exercise in hypertrophic cardiomyopathy2016In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 212, 47-53 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Development of left ventricular outflow tract obstruction (LVOTO) in patients with hypertrophic cardiomyopathy (HCM) is important for explaining symptoms and designing management. LVOTO is mostly caused by a combination of septal hypertrophy and systolic anterior movement of the mitral valve (SAM). The aim of the present study was to determine predictors of exercise induced LVOTO in a group of HCM patients.

    METHODS: We performed supine exercise Doppler echocardiography, including measurements of LV morphology and function and anterior mitral leaflet length, in 51 mildly symptomatic HCM (septal thickness≥15mm) and compared them with 50 healthy controls. Measurements were made at 1) rest, 2) Valsalva maneuver, 3) peak exercise and 4) post exercise. LVOTO was diagnosed as a LVOT gradient of >30mmHg at rest, after Valsalva and after exercise or ≥50mmHg at peak exercise.

    RESULTS: All patients stopped exercise because of exhaustion. 35% of the patients had resting LVOTO and 48% during Valsalva. At peak exercise, only 37% had LVOTO, who increased to 64% post exercise. Patients who developed LVOTO at peak exercise were more prone to continue having it post exercise (p<0.001), to have attenuated systolic blood pressure rise (p=0.011) and to have long anterior mitral valve leaflets (p<0.001). Backward multiple regression analysis showed the anterior mitral leaflet length as the strongest single independent predictor (β=0.36, p=0.010) for increased LVOT velocities, followed by basal septal thickness.

    CONCLUSION: In patients with HCM, LV outflow tract obstruction seems to be relatively uncommon during exercise but rather occurring minutes after stopping exercise. Exercise LVOTO seems to be determined by long anterior mitral leaflets in addition to the well established septal hypertrophy.

  • 42.
    Henein, Michael
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Holmner, Fredrik
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Long anterior mitral leaflet causing outflow tract obstruction in a symptomatic patient with hypertrophic cardiomyopathy: the role of mitral valve surgical correction2016In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 204, 86-87 p.Article in journal (Refereed)
  • 43.
    Henein, Michael
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindmark, Krister
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Impaired left ventricular systolic function reserve limits cardiac output and exercise capacity in HFpEF patients due to systemic hypertension2013In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 168, no 2, 1088-1093 p.Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: Heart failure (HF) patients with preserved left ventricular (LV) ejection fraction (EF) (HFpEF) due to systemic hypertension (SHT) are known to have limited exercise tolerance. Despite having normal EF at rest, we hypothesize that these patients have abnormal systolic function reserve limiting their exercise capacity. METHODS: Seventeen patients with SHT (mean age 68±9years) but no valve disease and 14 healthy individuals (mean age of 65±10years) underwent resting and peak exercise echocardiography using conventional, tissue Doppler and speckle tracking techniques. The differences between resting and peak exercise values were also analyzed (Δ). Exercise capacity was determined as the workload divided by body surface area. RESULTS: Resting values for left atrial (LA) volume/BSA (r=-0.66, p<0.001) and global longitudinal strain rate (GLSR) in early (e) and late (a) diastole (r=0.47 and 0.46, p<0.05 for both) correlated with exercise capacity. LVEF increased during exercise in normals (mean Δ EF=10±8%) but failed to do so in patients (mean Δ EF=0.6±9%, p<0.001 between groups). LV GLSR during systole (s) also failed to increase with exercise in patients, to the same extent as it did in normals (0.2±0.2 vs. 0.6±0.3 1/s, p<0.001). The difference between rest and exercise (Δ) in LV lateral wall systolic velocity from tissue Doppler (s') (0.71, p<0.001), Δ in cardiac output (r=0.60, p<0.001) and Δ GLSRs (r=0.48, p<0.05) all correlated with exercise capacity independent of changes in heart rate. CONCLUSION: HFpEF patients with hypertensive LV disease have significantly limited exercise capacity which is related to left atrial enlargement as well as compromised LV systolic function at the time of the symptoms. The limited myocardial systolic function reserve seems to be underlying important explanation for their limited exercise capacity.

  • 44.
    Henein, Michael
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Waldenström, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology. Umeå Heart Center.
    The normal impact of age and gender on right heart structure and function2014In: Echocardiography, ISSN 0742-2822, E-ISSN 1540-8175, Vol. 31, no 1, 5-11 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: As the proportion of elderly population increases rapidly, it might be difficult to differentiate physiological changes in cardiac function due to age from the pathophysiological ones. In addition, cardiac function variations with gender are well established. The right ventricular (RV) plays an important role in the overall cardiac function, but reference values varying with age and gender are lacking.

    MATERIAL AND METHODS: We studied 255 healthy individuals from a general population register, mean age of 58 ± 19 (range 22-89) years, 125 were females. We used 2D and M-mode echocardiography to measure RV inflow tract (RVIT) and RV outflow tract (RVOT) dimensions and fractional shortening (fs). Spectral Doppler echocardiography was also used.

    RESULTS: We found a modest decrease in RVIT dimensions (P < 0.05), but increase in RVOT dimensions with advancing age (P < 0.05). A small decrease in RVOT fs with age was also found (P < 0.05). Estimated pulmonary pressures and pulmonary vascular resistance increased (P < 0.001) as did RVOT wall thickness (P < 0.001), but RV diastolic function was not altered (P < 0.001) with age. Despite correction for the BSA, males showed larger RVIT dimensions (P < 0.001 for both), but RVOT end-diastolic dimension was larger in females (P < 0.05). RVIT and RVOT fractional shortening were increased in females (P < 0.01 for both).

    CONCLUSION: In a cohort of normal individuals, age has significant impact on RV structure and function, inlet area falls and outflow tract dimensions increase and fractional shortening also increase in females. In addition, RVOT wall thickness significantly increases and Doppler markers of pulmonary vascular resistance show a consistent rise. The age-related changes should carefully be considered when commenting on normality and when using absolute values.

  • 45.
    Henein, Michael Y
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Grönlund, Christer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Tossavainen, Erik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Söderberg, Stefan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Gonzalez, Manuel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Right and left heart dysfunction predict mortality in pulmonary hypertension2017In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 37, no 1, 45-51 p.Article in journal (Refereed)
    Abstract [en]

    In pulmonary hypertension (PH), the right heart dysfunction is a strong predictor of adverse clinical outcome, while the role of the left heart is not fully determined. The aim of this study was to identify predictors of mortality in precapillary PH including measures of both right and left heart function. We studied 34 patients (mean age 64 ± 13, range 31-82 years, 24 females) with precapillary PH, all of whom underwent detailed Doppler echocardiographic examination of the right and left heart function using conventional and speckle-tracking echocardiography. Patients were followed up for up to 8 years (mean 4·2 ± 1·9 years). At follow-up, 16 patients survived. Left ventricular (LV) filling time (P = 0·007), pulmonary artery acceleration time (P = 0·009), right atrial pressure (RAP) (P<0·001) and tricuspid regurgitation (TR) severity (P = 0·007) were worse in the deceased group. RV global longitudinal strain (GLS) (P = 0·001), RAP (P≤0·001), LV filling time (P<0·001) and TR severity (P<0·001) were the most accurate predictors, having the largest AUC (>0·65) and carried the highest risk for mortality (P<0·001 for all). The strongest predictors of mortality in precapillary PH indirectly reflect both left and right heart dysfunction including atrial structure and function disturbances. While an interaction pattern is observed, it needs to be confirmed in a larger cohort.

  • 46.
    Henein, Michael Y
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Left atrial function in volume versus pressure overloaded left atrium2015In: The International Journal of Cardiovascular Imaging, ISSN 1569-5794, E-ISSN 1875-8312, Vol. 31, no 5, 959-965 p.Article in journal (Refereed)
    Abstract [en]

    Left atrial (LA) pressure and volume overload both result in cavity enlargement and complications. LA volume has been shown to predict such complications, but it does not reflect myocardial function, which can be accurately assessed using myocardial deformation measurements. We hypothesized that volume overloaded LA have maintained myocardial function compared to pressure overloaded ones. We tested this hypothesis in 44 patient (mean age 62 ± 12 years) with LA volume overload (LAVOL) due to severe mitral regurgitation (MR) with no indirect signs of elevated left ventricular (LV) filling pressures based on Doppler measured isovolumic relaxation time >60 ms. We compared them with 24 (mean age 64 ± 12 years) patient with LA pressure overload (LAPOL) who proved to have PCWP >15 mmHg on right heart catheterization. Twenty-seven healthy controls (mean age 57 ± 10 years) constituted a control group. Patients with LAVOL had larger LA volumes, higher LV ejection fraction, global LV strain (LVGLS) and transmitral and pulmonary veins flow velocities (p < 0.05) and better LA atrial strain rate (LASR) function compared to LAPOL (p < 0.001). In LAVOL, the LASR during atrial contraction (LASRa) was lower than in controls (p < 0.05) indicating LA mechanical disturbances. LVGLS correlated with peak atrial longitudinal systolic strain in the whole group (r = -0.65, p < 0.001) and less so with LASRa (r = -0.43, p < 0.001) Conclusion: Irrespective of a smaller LA volume, LAVOL had less negative effect on LA myocardial function than LAPOL. Thus, monitoring atrial myocardial contraction might be useful in following patients with significant MR.

  • 47.
    Hörnsten, Rolf
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Pennlert, Johanna
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Heart complications in familial transthyretin amyloidosis: impact of age and gender.2010In: Amyloid: Journal of Protein Folding Disorders, ISSN 1350-6129, Vol. 17, no 2, 63-68 p.Article in journal (Refereed)
    Abstract [en]

    Heart arrhythmia is common in Swedish patients with familial amyloidotic polyneuropathy (FAP), as well as cardiomyopathy. We investigated the relationship between Holter ECG and echocardiographic findings in 108 FAP patients, with particular focus on age and gender differences. Female patients were younger than male patients at symptom onset (p < 0.01). Only 4 of 39 patients with septal hypertrophy were females. Regression analysis showed that age of onset, gender and duration of disease were significantly related with intraventricular septum (IVS) thickness. Sixty-five patients (25 females) presented with abnormal 24-h ECG recordings. IVS thickness was not significantly related to conduction disturbances or the presence of ventricular arrhythmia (VA). However, IVS thickness and atrial dimension were both related to increased rate of supraventricular arrhythmia (SVA). Male gender was clearly associated with more pronounced septal thickness of the heart. Conduction disturbances were not related to IVS thickness, indicating that the distribution and extent of infiltration of the heart by amyloid are heterogeneous and related to gender and age of onset. These findings highlight the necessity of 24-h ECGs to detect conduction disturbances, due to their occurrence in the absence of echocardiographic evidence of amyloid deposition in the myocardium.

  • 48.
    Hörnsten, Rolf
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Outcome of heart rate variability and ventricular late potentials after liver transplantation for familial amyloidotic polyneuropathy2008In: Amyloid: Journal of Protein Folding Disorders, ISSN 1350-6129, Vol. 15, no 3, 187-195 p.Article in journal (Refereed)
    Abstract [en]

    Reduced heart rate variability (HRV) is common in familial amyloidotic polyneuropathy (FAP), as well as cardiac arrhythmias. We examined the effects of liver transplantation (LTx) on 24-h HRV and ventricular late potentials. Twenty-one liver-transplanted FAP patients underwent Holter-ECG recordings and signal average electrocardiography recordings (SAECG) before and after LTx. Mean follow-up time after LTx was 21.7 months. Three patients had marked increased HRV after LTx, but this was in all cases caused by the development of subtle atrial arrhythmia and did not reflect an improvement in the cardiac autonomic control. In total, ten patients were excluded from analysis of HRV because of arrhythmia. Spectral analysis of HRV showed no significant differences before and after LTx in the remaining 11 patients. Positive late potentials were found in 33% of patients before LTx and this proportion was unchanged after LTx. Reduced HRV and positive late potentials are common in Swedish FAP patients, and remain stable, at least within the short term after transplantation. If an increase of HRV after transplantation is observed, it should raise the suspicion that the patient has developed subtle atrial arrhythmia.

  • 49.
    Hörnsten, Rolf
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Suhr, Ole B.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Olofsson, Bert-Ove
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Arrhythmia - a pitfall in tests of cardiac autonomic function after liver transplantation for familial amyloidotic polyneuropathy: a long-term follow-up of Swedish patients2012In: Amyloid: Journal of Protein Folding Disorders, ISSN 1350-6129, Vol. 19, no 2, 81-86 p.Article in journal (Refereed)
    Abstract [en]

    Liver transplantation (LT) is a potentially curative treatment for hereditary transthyretin amyloidosis, of which familial amyloid polyneuropathy (FAP) is the most common form in Sweden. This study investigated the long-term development in heart rate variability (HRV) after LT in Swedish FAP patients. HRV was analyzed before LT, and during a first (<40 months) and a second (>40 months) follow-up recording after transplantation, respectively. Power spectrum analysis was performed on 2-min sequences in the supine position and after passive tilt, after careful identification of patients with arrhythmia. Data were obtained from 33 patients, but 18 patients had developed cardiac arrhythmia or were pacemaker-treated (4 before LT and 14 after LT) and three patients had not performed the first follow-up recording. In the remaining 12 patients, HRV decreased between the pretransplant evaluation and the first follow-up, thereafter no significant changes were found. In conclusion, our study showed that the progressive development of cardiac arrhythmias after LT is a major pitfall when assessing cardiac autonomic function in FAP patients, especially in patients older than 40 years. In the minority of patients with sinus rhythm in all recordings, cardiac autonomic modulation remained stable after transplantation and no improvement was noted.

  • 50.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Karp, Kjell
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Assessment of myocardium at risk in pigs with single photon emission computed tomography and computerized vectorcardiography during transient coronary occlusion2000In: Scand Cardiovasc J, Vol. 34, no 2, 142-8 p.Article in journal (Refereed)
    Abstract [en]

    Since myocardium at risk (MAR) is the major prognosticator of final infarct size and outcome in patients with acute myocardial infarction, it is highly desirable to estimate the size of the acutely ischemic myocardium, that is the MAR, in these patients. We assessed MAR size by Tc-99m-sestamibi-SPECT and computerized vectorcardiography using autoradiography as reference method. Transient myocardial ischemia was achieved in 12 pigs by coronary artery occlusion with PTCA catheters. During the procedure, computerized vectorcardiography was continuously recorded. After injection of Tc-99m-sestamibi and gadolinium-153-labelled microspheres, MAR size was estimated by SPECT and post-mortem autoradiography. Different cut-off levels (50-70%) were compared with respect to MAR-SPECT. Tc-99m-sestamibi-SPECT showed a good correlation with autoradiography (r = 0.94). Computerized vectorcardiography showed a good correlation with autoradiography as well as with Tc-99m-sestamibi-SPECT (STC-VM: r = 0.75 and 0.80, respectively, ST-VM: 0.75 and 0.87, respectively). It was found that 1) MAR assessed by Tc-99m-sestamibi-SPECT correlates closely with the autoradiographic reference; 2) a lower cut-off point of 60% of maximum uptake for MAR by Tc-99m-sestamibi-SPECT gives the closest correlation with the autoradiographic reference; and 3) ST-VM and STC-VM correlate well with MAR assessed by Tc-99m-sestamibi-SPECT and autoradiography.

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