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  • 1. Almroth, Henrik
    et al.
    Höglund, Niklas
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    Boman, Kurt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Englund, Anders
    Jensen, Steen
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    Kjellman, Björn
    Tornvall, Per
    Rosenqvist, Mårten
    Atorvastatin and persistent atrial fibrillation following cardioversion: a randomized placebo-controlled multicentre study2009In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 30, no 7, p. 827-833Article in journal (Refereed)
    Abstract [en]

    AIMS: To evaluate the effect of atorvastatin in achieving stable sinus rhythm (SR) 30 days after electrical cardioversion (CV) in patients with persistent atrial fibrillation (AF). METHODS AND RESULTS: The study included 234 patients. The patients were randomized to treatment with atorvastatin 80 mg daily (n = 118) or placebo (n = 116) in a prospective, double-blinded fashion. Treatment was initiated 14 days before CV and was continued 30 days after CV. The two groups were well-balanced with respect to baseline characteristics. Mean age was 65 +/- 10 years, 76% of the patients were male and 4% had ischaemic heart disease. Study medication was well-tolerated in all patients but one. Before primary endpoint 12 patients were excluded. In the atorvastatin group 99 patients (89%) converted to SR at electrical CV compared with 95 (86%) in the placebo group (P = 0.42). An intention-to-treat analysis with the available data, by randomization group, showed that 57 (51%) in the atorvastatin group and 47 (42%) in the placebo group were in SR 30 days after CV (OR 1.44, 95%CI 0.85-2.44, P = 0.18). CONCLUSION: Atorvastatin was not statistically superior to placebo with regards to maintaining SR 30 days after CV in patients with persistent AF.

  • 2.
    Andersson, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Almroth, Henrik
    Höglund, Niklas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Tornvall, Per
    Englund, Anders
    Rosenqvist, Mårten
    Boman, Kurt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Markers of fibrinolysis as predictors for maintenance of sinus rhythm after electrical cardioversion2011In: Thrombosis Research, ISSN 0049-3848, E-ISSN 1879-2472, Vol. 127, no 3, p. 189-192Article in journal (Refereed)
    Abstract [en]

    No fibrinolytic component alone was found to be a predictor of recurrence of atrial fibrillation. In multivariate models lower PAI-1 mass was associated with sinus rhythm even after adjusting for CRP, markers of the metabolic syndrome and treatment with atorvastatin. Our findings suggest a patophysiological link between AF and PAI-1 mass but the relation to inflammation remains unclear.

  • 3. Bagge, Louise
    et al.
    Probst, Johan
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Blomström, Per
    Thelin, Stefan
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Blomström-Lundqvist, Carina
    Quality of life is not improved aftermitral valve surgery combined with epicardial left atrial cryoablation as compared with mitral valve surgery alone: a substudy of the double blind randomized SWEDish Multicentre Atrial Fibrillation study (SWEDMAF)2018In: Europace, ISSN 1099-5129, E-ISSN 1532-2092, Vol. 20, p. F343-F350Article in journal (Refereed)
    Abstract [en]

    Aims: Concomitant surgical ablation of atrial fibrillation (AF) in patients undergoing mitral valve surgery (MVS) has almost become routine despite lack of convincing information about improved quality-of-life (QOL) and clinical benefit. Quality-of-life was therefore assessed after MVS with or without epicardial left atrial cryoablation. Methods and results: Sixty-five patients with permanent AF randomized to MVS with or without left atrial cryoablation, in the doubleblinded multicentre SWEDMAF trial, replied to the Short Form 36 QOL survey at 6 and 12 months follow-up. The QOL scores at 12month follow-up did not differ significantly between patients undergoing MVS combined with cryoablation vs. those undergoing MVS alone regarding Physical Component Summary mean 42.8 (95% confidence interval 38.3-47.3) vs. mean 44.0 (40.1-47.7), P =0.700 or Mental Component Summary mean 53.1 (49.7-56.4) vs. mean 48.4 (44.6-52.2), P=0.075. All patients, irrespective of allocated procedure, reached the same QOL after surgery as an age-matched Swedish general population. The Physical Component Summary in patients with sinus rhythm did also not differ from those in AF at 12months; mean 45.4 (42.0-48.7) vs. mean 40.5 (35.5-45.6), P=0.096) nor was there a difference in Mental Component Summary; mean 51.0 (48.0-54.1) vs. mean 49.6 (44.6-54.5), P=0.581). Conclusion: Left atrial cryoablation added to MVS does not improve health-related QOL in patients with permanent AF, a finding that raises concerns regarding recommendations made for this combined procedure.

  • 4.
    Bajraktari, Gani
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Ibrahimi, Pranvera
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jashari, Fisnik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen M
    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.
    Combining electrical and global mechanical markers of LV dyssynchrony optimizes patient selection for cardiac resynchronization therapy2014Article in journal (Refereed)
  • 5.
    Bajraktari, Gani
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Ibrahimi, Pranvera
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jashari, Fisnik
    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.
    Henein, Michael Y.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Total isovolumic time, a marker of global left ventricular dyssynchrony, predicts response to Cardiac Resynchronization Therapy in heart failure patients2014In: European Journal of Heart Failure, ISSN 1388-9842, E-ISSN 1879-0844, Vol. 16, no Sup. 2, p. 154-154Article in journal (Other academic)
  • 6.
    Bajraktari, Gani
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Ibrahimi, Pranvera
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jashari, Fisnik
    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.
    Henein, Michael Y.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Total isovolumic time, a marker of global left ventricular dyssynchrony, predicts response to Cardiac Resynchronization Therapy in heart failure patients with atrial fibrillation2014In: European Journal of Heart Failure, ISSN 1388-9842, E-ISSN 1879-0844, Vol. 16, p. 56-56Article in journal (Other academic)
  • 7.
    Bajraktari, Gani
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Ibrahimi, Pranvera
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jashari, Fisnik
    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.
    Jensen, Steen M
    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.
    Combined electrical and global markers of dyssynchrony predict clinical response to Cardiac Resynchronization Therapy2014In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 48, no 5, p. 304-310Article in journal (Refereed)
    Abstract [en]

    AIM: To assess potential additional value of global left ventricular (LV) dyssynchrony markers in predicting cardiac resynchronization therapy (CRT) response in heart failure (HF) patients. METHODS: We included 103 HF patients (mean age 67 +/- 12 years, 83% male) who fulfilled the guidelines criteria for CRT treatment. All patients had undergone full clinical assessment, NT-proBNP and echocardiographic examination. Global LV dyssynchrony was assessed using total isovolumic time (t-IVT) and Tei index. On the basis of reduction in the NYHA class after CRT, patients were divided into responders and non-responders. RESULTS: Prolonged t-IVT [0.878 (range, 0.802-0.962), p = 0.005], long QRS duration [0.978 (range, 0.960-0.996), p = 0.02] and high tricuspid regurgitation pressure drop [1.047 (range, 1.001-1.096), p = 0.046] independently predicted response to CRT. A t-IVT >= 11.6 s/min was 67% sensitive and 62% specifi c (AUC 0.69, p = 0.001) in predicting CRT response. Respective values for a QRS >= 151 ms were 66% and 62% (AUC 0.65, p = 0.01). Combining the two variables had higher specifi city (88%) in predicting CRT response. In atrial fibrillation (AF) patients, only prolonged t-IVT [0.690 (range, 0.509 -0.937), p = 0.03] independently predicted CRT response. CONCLUSION: Combining prolonged t-IVT and the conventionally used broad QRS duration has a significantly higher specifi city in identifying patients likely to respond to CRT. Moreover, in AF patients, only prolonged t-IVT independently predicted CRT response.

  • 8. Blomström-Lundqvist, Carina
    et al.
    Gizurarson, Sigfus
    Schwieler, Jonas
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine. Heart Centre, Umeå University, Umeå, Sweden.
    Bergfeldt, Lennart
    Kennebäck, Göran
    Rubulis, Aigars
    Malmborg, Helena
    Raatikainen, Pekka
    Lönnerholm, Stefan
    Höglund, Niklas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine. Heart Centre, Umeå University, Umeå, Sweden.
    Mörtsell, David
    Effect of Catheter Ablation vs Antiarrhythmic Medication on Quality of Life in Patients With Atrial Fibrillation: the CAPTAF Randomized Clinical Trial2019In: Journal of the American Medical Association (JAMA), ISSN 0098-7484, E-ISSN 1538-3598, Vol. 321, no 11, p. 1059-1068Article in journal (Refereed)
    Abstract [en]

    Importance: Quality of life is not a standard primary outcome in ablation trials, even though symptoms drive the indication.

    Objective: To assess quality of life with catheter ablation vs antiarrhythmic medication at 12 months in patients with atrial fibrillation.

    Design, setting, and participants: Randomized clinical trial at 4 university hospitals in Sweden and 1 in Finland of 155 patients aged 30-70 years with more than 6 months of atrial fibrillation and treatment failure with 1 antiarrhythmic drug or beta-blocker, with 4-year follow-up. Study dateswere July 2008-September 2017. Major exclusionswere ejection fraction <35%, left atrial diameter > 60 mm, ventricular pacing dependency, and previous ablation.

    Interventions: Pulmonary vein isolation ablation (n= 79) or previously untested antiarrhythmic drugs (n= 76).

    Main outcomes and measurement: Primary outcomewas the General Health subscale score (Medical Outcomes Study 36-Item Short-Form Health Survey) at baseline and 12 months, assessed unblinded (range, 0 [worst] to 100 [best]). There were 26 secondary outcomes, including atrial fibrillation burden (% of time) from baseline to 12 months, measured by implantable cardiac monitors. The first 3 months were excluded from rhythm analysis.

    Results: Among 155 randomized patients (mean age, 56.1 years; 22.6% women), 97% completed the trial. Of 79 patients randomized to receive ablation, 75 underwent ablation, including 2 who crossed over to medication and 14 who underwent repeated ablation procedures. Of 76 patients randomized to receive antiarrhythmic medication, 74 received it, including 8 who crossed over to ablation and 43 for whom the first drug used failed. General Health score increased from 61.8 to 73.9 points in the ablation group vs 62.7 to 65.4 points in the medication group (between-group difference, 8.9 points; 95% CI, 3.1-14.7; P=.003). Of 26 secondary end points, 5 were analyzed; 2 were null and 2 were statistically significant, including decrease in atrial fibrillation burden (from 24.9% to 5.5% in the ablation group vs 23.3% to 11.5% in the medication group; difference -6.8%[95% CI, -12.9% to -0.7%]; P=.03). Of the Health Survey subscales, 5 of 7 improved significantly. Most common adverse events were urosepsis (5.1%) in the ablation group and atrial tachycardia (3.9%) in the medication group.

    Conclusions and relevance: Among patients with symptomatic atrial fibrillation despite use of antiarrhythmic medication, the improvement in quality of life at 12 months was greater for those treated with catheter ablation compared with antiarrhythmic medication. Although the study was limited by absence of blinding, catheter ablation may offer an advantage for quality of life.

  • 9. Blomström-Lundqvist, Carina
    et al.
    Johansson, Birgitta
    Berglin, Eva
    Avd för molekylär och klinisk medicin, Institutionen för medicin vid Sahlgrenska akademin.
    Nilsson, Leif
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Thelin, Stefan
    Holmgren, Anders
    Edvardsson, Nils
    Källner, Göran
    Blomström, Per
    A randomized double-blind study of epicardial left atrial cryoablation for permanent atrial fibrillation in patients undergoing mitral valve surgery: the SWEDish Multicentre Atrial Fibrillation study (SWEDMAF).2007In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 28, no 23, p. 2902-2908Article in journal (Refereed)
  • 10.
    Diamant, Ulla-Britt
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Winbo, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stattin, Eva-Lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Vectorcardiographic recordings of the Q-T interval in a pediatric long Q-T syndrome population2013In: Pediatric Cardiology, ISSN 0172-0643, E-ISSN 1432-1971, Vol. 34, no 2, p. 245-249Article in journal (Refereed)
    Abstract [en]

    Measurements of the Q-T interval are less reliable in children than in adults. Identification of superior diagnostic tools is warranted. This study aimed to investigate whether a vectorcardiogram (VCG) recorded from three orthogonal leads (X, Y, Z) according to Frank is superior to a 12-lead electrocardiogram (ECG) in providing a correct long Q-T syndrome (LQTS) diagnosis in children. This LQTS group consisted of 35 genetically confirmed carriers of mutations in the KCNQ1 (n = 29) and KCNH2 (n = 6) genes. The control group consisted of 35 age- and gender-matched healthy children. The mean age was 7 years in the LQTS group and 6.7 years in the control group (range, 0.5-16 years). The corrected Q-T interval (QT(c)) was measured manually (QT(man)) by one author (A.W.). The 12-lead ECG automatic measurements (QT(ECG)) and interpretation (QT(Interpret)) of QT(c) were performed with the Mac5000 (GE Medical System), and the VCG automatic measurements (QT(VCG)) were performed with the Mida1000, CoroNet (Ortivus AB, Sweden). By either method, a QT(c) longer than 440 ms was considered prolonged and indicative of LQTS. Of the 35 children with genetically confirmed LQTS, 30 (86 %) received a correct diagnosis using QT(VCG), 29 (82 %) using QT(man), 24 (69 %) using QT(ECG), and 17 (49 %) using QT(Interpret). Specificity was 0.80 for QT(VCG), 0.83 for QT(man), 0.77 for QT(ECG), and 0.83 for QT(Interpret). The VCG automatic measurement of QT(c) seems to be a better predictor of LQTS than automatic measurement and interpretation of 12-lead ECG.

  • 11.
    Diamant, Ulla-Britt
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Vahedi, Farzad
    Sahlgrenska Akademin Göteborgs Universitet.
    Winbo, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stattin, Eva-Lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Bergfeldt, Lennart
    Sahlgrenska Akademin Göteborgs Universitet.
    Electrophysiological phenotype in the LQTS mutations Y111C and R518X in the KCNQ1 gene2013In: Journal of applied physiology, ISSN 8750-7587, E-ISSN 1522-1601, Vol. 115, no 10, p. 1423-1432Article in journal (Refereed)
    Abstract [en]

    Long QT syndrome is the prototypical disorder of ventricular repolarization (VR), and a genotype-phenotype relation is postulated. Furthermore, although increased VR heterogeneity (dispersion) may be important in the arrhythmogenicity in long QT syndrome, this hypothesis has not been evaluated in humans and cannot be tested by conventional electrocardiography. In contrast, vectorcardiography allows assessment of VR heterogeneity and is more sensitive to VR alterations than electrocardiography. Therefore, vectorcardiography was used to compare the electrophysiological phenotypes of two mutations in the LQT1 gene with different in vitro biophysical properties, and with LQT2 mutation carriers and healthy control subjects. We included 99 LQT1 gene mutation carriers (57 Y111C, 42 R518X) and 19 LQT2 gene mutation carriers. Potassium channel function is in vitro most severely impaired in Y111C. The control group consisted of 121 healthy subjects. QRS, QT, and T-peak to T-end (Tp-e) intervals, measures of the QRS vector and T vector and their relationship, and T-loop morphology parameters were compared at rest. Apart from a longer heart rate-corrected QT interval (QT heart rate corrected according to Bazett) in Y111C mutation carriers, there were no significant differences between the two LQT1 mutations. No signs of increased VR heterogeneity were observed among the LQT1 and LQT2 mutation carriers. QT heart rate corrected according to Bazett and Tp-e were longer, and the Tp-e-to-QT ratio greater in LQT2 than in LQT1 and the control group. In conclusion, there was a marked discrepancy between in vitro potassium channel function and in vivo electrophysiological properties in these two LQT1 mutations. Together with previous observations of the relatively low risk for clinical events in Y111C mutation carriers, our results indicate need for cautiousness in predicting in vivo electrophysiological properties and the propensity for clinical events based on in vitro assessment of ion channel function alone.

  • 12.
    Diamant, Ulla-Britt
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Winbo, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stattin, Eva-Lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Kesek, Milos
    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.
    Two automatic QT algorithms compared with manual measurement in identification of long QT syndrome2010In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 43, no 1, p. 25-30Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Long QT syndrome (LQTS) is an inherited disorder that increases the risk of syncope and malignant ventricular arrhythmias, which may result in sudden death.

    METHODS: We compared manual measurement by 4 observers (QT(manual)) and 3 computerized measurements for QT interval accuracy in the diagnosis of LQTS: 1. QT measured from the vector magnitude calculated from the 3 averaged orthogonal leads X, Y, and Z (QTVCG) and classified using the same predefined QTc cut-points for classification of QT prolongation as in manual measurements; 2. QT measured by a 12-lead electrocardiogram (ECG) program (QTECG) and subsequently classified using the same cut-points as in (1) above; 3. The same QT value as in (2) above, automatically classified by a 12-lead ECG program with thresholds for QT prolongation adjusted for age and sex (QTinterpret). The population consisted of 94 genetically confirmed carriers of KCNQ1 (LQT1) and KCNH2 (LQT2) mutations and a combined control group of 28 genetically confirmed noncarriers and 66 unrelated healthy volunteers.

    RESULTS: QT(VCG) provided the best combination of sensitivity (89%) and specificity (90%) in diagnosing LQTS, with 0.948 as the area under the receiver operating characteristic curve. The evaluation of QT measurement by the 4 observers revealed a high interreader variability, and only 1 of 4 observers showed acceptable level of agreement in LQTS mutation carrier identification (kappa coefficient >0.75).

    CONCLUSION: Automatic QT measurement by the Mida1000/CoroNet system (Ortivus AB, Danderyd, Sweden) is an accurate, efficient, and easily applied method for initial screening for LQTS.

  • 13. El-Maasarany, Shirley H
    et al.
    Elazab, Eman E B
    Jensen, Steen
    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.
    A-V nodal artery anatomy and relations to the posterior septal space and its contents2010In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 141, no 1, p. 92-98Article in journal (Refereed)
    Abstract [en]

    BACKGROUND AND AIM: Radiofrequency catheter ablation treats resistant nodal re-entrant tachycardia but carries a risk to AV conduction system and its vessels. We aimed to study the origin of the A-V nodal artery (AVNA) and its course within the posterior septal space (PSS). METHODS: Twenty embalmed human hearts of both sexes (16 males) age, 25-60 years, were dissected to study the PPS and its arteries down to their destination. RESULTS: The PSS is a four sided pyramidal space, at the crux of the heart, with its base made of the pericardium. It is made of four; right upper and lower and left upper and lower walls corresponding to the right atrium and ventricle and left atrium and ventricle, respectively. The right coronary artery (RCA) crossed the base from the right to the left angle, to lie inferior and adherent to the terminal part of the coronary sinus (CS). The posterior interventricular artery, the ventricular branches of the RCA, the middle cardiac vein and the ventricular veins, all crossed the base of the space to their final destination. AVNA originated from either the RCA itself or one of its branches. Double AVNA was encountered in 14 specimens with the upper artery larger and passed between the right and left atria and the lower artery smaller and crossed the space adjacent to the right ventricle. CONCLUSIONS: These findings highlight the importance of the PSS and its structural relations, in particular to the AVNA, that should be considered during various interventional procedures.

  • 14.
    Höglund, Niklas
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Andersson, Jonas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Almroth, Henrik
    Tornvall, Per
    Englund, Anders
    Rosenqvist, Marten
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Boman, Kurt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    The predictive value of C-reactive protein on recurrence of atrial fibrillation after cardioversion with or without treatment with atorvastatin2013In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 167, no 5, p. 2088-2091Article in journal (Refereed)
    Abstract [en]

    Background: The aim of this study was to investigate whether high-sensitivity C-reactive protein (hsCRP) levels prior to cardioversion (CV) predict recurrence of atrial fibrillation (AF) in patients randomized to treatment with either atorvastatin or placebo 30 and 180 days after CV. Methods: This was a prespecified substudy of 128 patients with persistent AF randomized to treatment with atorvastatin 80 mg/day or placebo, initiated 14 days before CV, and continued 30 days after CV. HsCRP levels were measured at randomization, at the time of CV, and 2 days and 30 days after CV. Results: In univariate analysis of those who were in sinus rhythm 2 h after CV, hsCRP did not significantly (odds ratio [OR] 1.11, 95% confidence interval [CI] 0.99-1.25) predict recurrence of AF at 30 days. However, after adjusting for treatment with atorvastatin, hsCRP predicted the recurrence of AF (OR 1.14, 95% CI 1.01-1.27). In a multivariate logistic regression analysis with gender, age, body mass index (BMI), smoking, cholesterol, and treatment with atorvastatin as covariates, the association was still significant (OR 1.14, 95% CI 1.01-1.29). Six months after CV, hsCRP at randomization predicted recurrence of AF in both univariate analysis (OR 1.30, 95% CI 1.06-1.60) and in multivariate logistic regression analysis (OR 1.33, 95% CI 1.06-1.67). Conclusion: HsCRP was associated with AF recurrence one and six months after successful CV of persistent AF. However, the association at one month was significant only after adjusting for atorvastatin treatment.

  • 15.
    Höglund, Niklas
    et al.
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    Rönn, Folke
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    Tollefsen, Titti
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    Jensen, Steen
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    Kesek, Milos
    Department of Cardiology, Heart Centre, University Hospital, S-901 85 Umeå, Sweden.
    U22 protocol as measure of symptomatic improvement after catheter ablation of atrial fibrillation2013In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 118, no 4, p. 240-246Article in journal (Refereed)
    Abstract [en]

    Introduction. Left atrial catheter ablation is useful as symptomatic treatment in selected patients with atrial fibrillation (AF). Evaluation requires measurement of arrhythmia-related symptoms. Many of the published protocols have drawbacks and have been used in AF only, with no possible comparison to other ablations that compete for the same resources. U22 is a published protocol that quantifies paroxysmal tachycardia symptoms through scales with 11 answer alternatives, translated into discrete numerical scales 0-10. It has been shown to reflect the clinical improvement after ablation of supraventricular tachycardia. Here we report the use of U22 in measuring improvement after catheter ablation for AF. Material and methods. A total of 105 patients underwent first-time ablation for AF and answered U22 and SF-36 forms at baseline and follow-up 304 (SD 121) days after ablation. Independently, the patients underwent a clinical follow-up. All decisions regarding medication and reablation were taken without knowledge of the symptom scores. Results. The U22 scores for well-being, arrhythmia as cause for impaired well-being, derived time-aspect score for arrhythmia, and discomfort during attack detected relevant improvements of symptoms after the ablation. U22 showed larger improvement in patients undergoing only one procedure than in patients who later underwent repeated interventions, thus reflecting the independent clinical decision for reablation. Conclusion. U22 quantifies the symptomatic improvement after AF ablation with adequate internal consistency and construct validity. U22 mirrors aspects of the arrhythmia symptomatology other than SF-36.

  • 16.
    Höglund, Niklas
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Sahlin, Carin
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Kesek, Milos
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Franklin, Karl A.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Cardioversion of atrial fibrillation does not affect obstructive sleep apnea2017In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 122, no 2, p. 114-118Article in journal (Refereed)
    Abstract [en]

    Background: Sleep apnea is common in patients with atrial fibrillation, but the effect of the cardioversion of atrial fibrillation to sinus rhythm on central and obstructive apneas is mainly unknown. The primary aim of the study was to analyze the association between cardioversion of atrial fibrillation and sleep apneas, to investigate whether obstructive or central sleep apneas are reduced following cardioversion. A secondary objective was to study the effect on sleep quality. Methods: Twenty-three patients with atrial fibrillation were investigated using overnight polysomnography, including esophagus pressure monitoring and ECG, before and after the cardioversion of persistent atrial fibrillation. Results: Obstructive sleep apnea occurred in 17/23 patients (74%), and central sleep apnea in 6/23 patients (26%). Five patients had both obstructive and central sleep apnea. Sinus rhythm at follow-up was achieved in 16 patients. The obstructive apnea-hypopnea index, central apnea-hypopnea index, and the number of patients with obstructive or central sleep apnea did not differ before and after restoration of sinus rhythm. Sleep time, sleep efficiency, time in different sleep stages, and subjective daytime sleepiness were normal and unaffected by cardioversion. Conclusions: Both obstructive and central sleep apneas are highly prevalent in patients with persistent atrial fibrillation. Obstructive sleep apneas are unaffected by the cardioversion of atrial fibrillation to sinus rhythm. The sleep pattern is normal and unaffected by cardioversion in patients with atrial fibrillation. Clinical Trial Registration: Trial number NCT00429884.

  • 17.
    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, E-ISSN 1744-2818, Vol. 17, no 2, p. 63-68Article 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.

  • 18.
    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, E-ISSN 1744-2818, Vol. 15, no 3, p. 187-195Article 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.

  • 19.
    Hörnsten, Rolf
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Suhr, Ole B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Ventricular late potentials in familial amyloidotic polyneuropathy2006In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 39, no 1, p. 57-62Article in journal (Refereed)
    Abstract [en]

    It is well known that cytokines are highly involved in the disease process of rheumatoid arthritis (RA). Recently, targeting of neuropeptides has been suggested to have potential therapeutic effects in RA. The aim of this study was to investigate possible interrelations between five neuropeptides (bombesin/gastrin-releasing peptide (BN/GRP), substance P (SP), vasoactive intestinal peptide, calcitonin-gene-related peptide, and neuropeptide Y) and the three cytokines tumour necrosis factor (TNF)-alpha, IL-6, and monocyte chemoattractant protein-1 in synovial fluid of patients with RA. We also investigated possible interrelations between these neuropeptides and soluble TNF receptor 1 in serum from RA patients. Synovial fluid and sera were collected and assayed with ELISA or RIA. The most interesting findings were correlations between BN/GRP and SP and the cytokines. Thus, in synovial fluid, the concentrations of BN/GRP and SP grouped together with IL-6, and SP also grouped together with TNF-alpha and monocyte chemoattractant protein-1. BN/GRP and SP concentrations in synovial fluid also grouped together with the erythrocyte sedimentation rate. In the sera, BN/GRP concentrations and soluble TNF receptor 1 concentrations were correlated. These results are of interest because blocking of SP effects has long been discussed in relation to RA treatment and because BN/GRP is known to have trophic and growth-promoting effects and to play a role in inflammation and wound healing. Furthermore, the observations strengthen a suggestion that combination treatment with agents interfering with neuropeptides and cytokines would be efficacious in the treatment of RA. In conclusion, BN/GRP and SP are involved together with cytokines in the neuroimmunomodulation that occurs in the arthritic joint.

  • 20.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    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.
    On-line computerized vectorcardiography: influence of body position, heart rate, radiographic contrast fluid and myocardial ischemia1997In: Cardiology, Vol. 88, no 6, p. 576-84Article in journal (Refereed)
    Abstract [en]

    On-line computerized vectorcardiography (cVCG) is increasingly being used for continuous monitoring of myocardial ischemia, however, little is known about factors other than ischemia causing electrocardiographic abnormalities. This paper describes how three important cVCG parameters, STC-VM, ST-VM and QRS-VD, are affected by different body positions, myocardial ischemia, contrast injection and increasing heart rate in patients with and without coronary artery disease. The main findings of the study are: contrast injection and different body positions caused major changes in QRS-VD but affected ST-VM and STC-VM to a minor degree. Increasing heart rate by atrial pacing produced substantial changes in all three parameters. Ischemia during angioplasty also produced changes in all three parameters, STC-VM being the most sensitive parameter. In conclusion: (1) STC-VM (> or = 50 microV) is the most valuable parameter for monitoring ischemia; (2) we propose ST-VM > or = 50 microV as criterion instead of previously used 25 microV; (3) QRS-VD cannot be used as a single marker of ischemia, and (4) electrocardiographic changes induced by increased heart rate should be taken into account during interpretation.

  • 21.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Osterman, Göran
    Reiz, Sebastian
    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.
    On-line computerized vectorcardiography monitoring of myocardial ischemia during coronary angioplasty: comparison with 12-lead electrocardiography1994In: Coron Artery Dis, Vol. 5, no 6, p. 507-14Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: With new interventions minimizing ischemic myocardial injury, accurate and reliable techniques for the detection and continuous monitoring of myocardial ischemia are essential. We compared two techniques used for the detection of myocardial ischemia during coronary angioplasty: on-line computerized vectorcardiographic (cVCG) monitoring and the standard electrocardiography (ECG) leads or the complete 12-lead ECG. METHODS: Thirty patients scheduled for routine angioplasty were included in the study. cVCG was recorded continuously. The electrodes were placed according to the lead system described by Frank and connected to a computerized system for on-line vectorcardiography. A 12-lead ECG was recorded simultaneously. The absolute variable spatial ST vector magnitude (ST-VM) and the relative variable spatial ST change vector magnitude (STC-VM) were calculated and compared with the standard 12-lead ECG for the detection of ischemia. RESULTS: The sum of deviation in ST segment in all 12 standard ECG leads correlated closely with STC-VM, irrespective of which artery was occluded. STC-VM indicated ischemia during the first balloon inflation in 87% of the patients and demonstrated ischemia in more patients than the standard 12-lead ECG. Myocardial ischemia was not demonstrated by ST-VM in five out of 26 patients with ischemia according to STC-VM. In these cases, mainly directional vector changes and fewer changes in magnitude were observed. CONCLUSION: Compared with 12-lead ECG, on-line cVCG is a more sensitive method of detecting myocardial ischemia during coronary angioplasty and the reading is easier and faster. Our results support STC-VM > or = 0.050 mV as the criterion for ischemia during angioplasty; ST-VM should be applied together with STC-VM.

  • 22.
    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, p. 142-8Article 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.

  • 23.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Kesek, Milos
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    [No evidence of positive effects of pacemaker use in paroxysmal atrial fibrillation]2005In: Lakartidningen, ISSN 0023-7205, Vol. 102, no 22, p. 1722-6Article in journal (Refereed)
  • 24.
    Jensen, Steen M
    et al.
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Kesek, Milos
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    [Implantable defibrillator--with focus on primary prevention. Detailed patient information about risks and benefits is required]2009In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 106, no 48, p. 3236, 3238-3241Article in journal (Refereed)
  • 25.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Posan, Emoke
    Redfern, Damian
    Petrellis, Basilios
    Klein, George J
    Syncope and wide QRS tachycardia.2005In: Pacing Clin Electrophysiol, ISSN 0147-8389, Vol. 28, no 7, p. 708-9Article in journal (Refereed)
  • 26.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Stattin, Eva-lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    [Long QT syndrome can be effectively treated. Important to identify mutation carriers]2007In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 104, no 40, p. 2866-2870Article in journal (Refereed)
  • 27. Johansson, Birgitta
    et al.
    Bech-Hanssen, Odd
    Berglin, Eva
    Blomström, Per
    Holmgren, Anders
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Källner, Göran
    Nilsson, Leif
    Thelin, Stefan
    Karlsson, Thomas
    Edvardsson, Nils
    Blomström-Lundqvist, Carina
    Atrial function after left atrial epicardial cryoablation for atrial fibrillation in patients undergoing mitral valve surgery2012In: Journal of interventional cardiac electrophysiology (Print), ISSN 1383-875X, E-ISSN 1572-8595, Vol. 33, no 1, p. 85-91Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To explore the effects on atrial and ventricular function of restoring sinus rhythm (SR) after epicardial cryoablation and closure of the left atrial appendage (LAA) in patients with mitral valve disease and atrial fibrillation (AF) undergoing surgery.

    METHODS: Sixty-five patients with permanent AF were randomized to mitral valve surgery combined with left atrial epicardial cryoablation and LAA closure (ABL group, n = 30) or to mitral valve surgery alone (control group, n = 35). Two-dimensional and Doppler echocardiography were performed before and 6 months after surgery.

    RESULTS: At 6 months, 73% of the patients in the ABL group and 46% of the controls were in SR. Patients in SR at 6 months had a reduction in their left ventricular diastolic diameter while the left ventricular ejection fraction was unchanged. In patients remaining in AF, the left ventricular ejection fraction was lower than at baseline. The left atrial diastolic volume was reduced after surgery, more in patients with SR than AF. In patients in SR, the peak velocity during the atrial contraction and the reservoir function were lower in the ABL group than in the control group.

    CONCLUSIONS: In patients in SR, signs of atrial dysfunction were observed in the ABL but not the control group. Atrial dysfunction may have existed before surgery, but the difference between the groups implies that the cryoablation procedure and/or closure of the LAA might have contributed.

  • 28.
    Jonsson, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Karlsson, M
    Wiklund, U
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Stegmayr, Bernd
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Measurement of cardiac rhythm in connection to haemodialysis with focus on a possible interference due to leakage current: a pilot study of patients in chronic haemodialysisArticle in journal (Refereed)
  • 29.
    Kesek, Milos
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Englund, Anders
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jensen-Urstad, Mats
    Entrapment of circular mapping catheter in the mitral valve.2007In: Heart Rhythm, ISSN 1547-5271, Vol. 4, no 1, p. 17-9Article in journal (Refereed)
  • 30.
    Kesek, Milos
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Lindmark, Daniel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Rashid, Amir
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Increased risk of late pacemaker implantation after ablation for atrioventricular nodal reentry tachycardia: A 10-year follow-up of a nationwide cohort2019In: Heart Rhythm, ISSN 1547-5271, E-ISSN 1556-3871, Vol. 16, no 8, p. 1182-1188Article in journal (Refereed)
    Abstract [en]

    Background: Catheter ablation of the slow pathway is the standard treatment of atrioventricular nodal reentry tachycardia (AVNRT) with a well described low risk of periprocedural atrioventricular block. Less is known about the risk of pacemaker implantation late after ablation.

    Objective: We aimed to quantify the risk of late pacemaker implantation in a countrywide cohort undergoing first-time ablation for AVNRT.

    Methods: All patients undergoing first-time ablation for AVNRT in Sweden from 2004 to 2014 were identified from the Swedish catheter ablation registry and matched against the Swedish Pacemaker and ICD registry. The cohort was compared to patients ablated for an accessory pathway (AP) and to matched controls.

    Results: During follow-up of 2039 days, pacemaker was implanted later than 30 days after ablation in 96 of 6842 patients with AVNRT (1.4%), 29 of 4065 patients with AP (0.7%) (P = .001), and 124 of 33,270 controls (0.4%) (P < .00001). A periprocedural pacemaker (≤30 days postablation) was implanted in 32 of 6877 patients with AVNRT (0.5%) and 9 of 4079 patients with AP (0.2%) (P = .05). With cryoablation, 5 patients needed periprocedural pacemaker implantation. Pacemakers were implanted before ablation in 88 of 6977 patients with AVNRT (1.3%) and 11 of 4100 patients with AP (0.3%); the prevalence of pacemaker implants in controls was 124 of 33,270 (0.4%) (P < .00001 for both comparisons).

    Conclusion: The risk of late pacemaker implantation after AVNRT ablation was low but 3 times higher than that in the control population and 3 times higher than the risk of periprocedural pacemaker implantation. Similar results were observed with cryoablation and radiofrequency ablation. Ablation may not be the cause of increased late pacemaker implantation risk.

  • 31.
    Kesek, Milos
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Two Cases of LQT Syndrome with Malignant Syncope after Switch from Propranolol to Bisoprolol2016In: Pacing and Clinical Electrophysiology, ISSN 0147-8389, E-ISSN 1540-8159, Vol. 39, no 3, p. 305-306Article in journal (Refereed)
    Abstract [en]

    Propranolol in slow-release form has been the first-line treatment in long QT (LQT) until it was withdrawn from the market. We describe two cases where a switch to bisoprolol resulted in worsening of arrhythmia control: A man with LQT2, asymptomatic on propranolol, experienced syncope after switching to bisoprolol 5 mg daily. He switched back to propranolol and has remained asymptomatic during subsequent 12 months. A man with classical Jervell Lange-Nielsen syndrome, previous gangliectomy, and ICD implantation, switched to bisoprolol 5 mg daily. Four months later he experienced a tachycardia storm. He switched back to propranolol and has remained free from arrhythmias during subsequent 12 months.

  • 32.
    Kesek, Milos
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Tollefsen, Titti
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Höglund, Niklas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Symptomatic improvement after catheter ablation of supraventricular tachycardia measured by the arrhythmia-specific questionnaire U222011In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 116, no 1, p. 52-59Article in journal (Refereed)
    Abstract [en]

    After successful ablation of accessory pathway and atrioventricular nodal re-entrant tachycardia, the U22 protocol detected a relevant increase in arrhythmia-related well-being. Modest improvement in general well-being was detected by the SF-36 protocol.

  • 33.
    Kesek, Milos
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Tollefsen, Titti
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Höglund, Niklas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Näslund, Ulf
    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.
    U22, a protocol to quantify symptoms associated with supraventricular tachycardia.2009In: Pacing and Clinical Electrophysiology, ISSN 0147-8389, E-ISSN 1540-8159, ISSN 1540-8159, Vol. 32, no S1, p. S105-S108Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The main indication for ablation of supraventricular tachyarrhythmias (SVTA) is symptomatic relief. Specific paroxysmal symptoms cannot be quantified with general measures of quality of life, such as with the SF-36 questionnaire. U22 is a new protocol which measures the effects of arrhythmia on well-being, the intensity of discomfort during an episode, the type and temporal characteristics of dominant symptoms, and the duration and frequency of episodes. Discrete 0-10 scales are used. Unlike SF-36, U22 can be used in individual patients. METHODS: U22 and SF-36 protocols were used in the symptomatic evaluation of 88 patients (mean age = 49.6 +/- 16.4 years; 43 men), who underwent catheter ablation of SVTA. Results: The U22 scores (SD) for (a) well-being (10 being best), (b) effects of arrhythmia on well-being (10 being worst), and (c) discomfort during arrhythmia (10 being worst) were 5.6 (2.7), 7.5 (2.8), and 8.0 (2.4), respectively. For comparison, the physical and mental component summaries of SF-36 were 45.3 (11.0) and 45.2 (12.1), respectively, slightly lower than the expected normal of 50. The intensity of dominant symptom scored by U22 was 9.7 (1.2), 10 being worst. In 29% of patients > or =4 symptoms were equally dominant. Multiple dominant symptoms in U22 were associated with a low general well-being in SF-36. CONCLUSION: We found U22 useful to quantify symptoms associated with SVTA.

  • 34.
    Kesek, Milos
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Wallenius, N
    Rönn, Folke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Höglund, Niklas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Reduction of fluoroscopy duration in radiofrequency ablation obtained by the use of a non-fluoroscopic catheter navigation system.2006In: Europace, Vol. 8, no 12, p. 1027-30Article in journal (Refereed)
    Abstract [en]

    AIMS: Radiofrequency (RF) ablation requires placement of several catheters at critical positions. The catheters are positioned with fluoroscopy, resulting in a significant radiation exposure. We have investigated to what degree an intracardiac navigation system reduces the fluoroscopy duration in different groups of routine RF ablations. METHODS AND RESULTS: The fluoroscopy time was evaluated in 365 consecutive routine RF ablations, performed between 2002 and 2005. An intracardiac navigation system (LocaLisa, Medtronic) was used from 2003. The data were prospectively entered into a database and subsequently retrieved, and the procedures classified as being performed with fluoroscopy only or with the aid of the LocaLisa system. After introduction of the LocaLisa system, the median fluoroscopy time decreased from 24 to 10 min in the 141 atrioventricular nodal re-entry tachycardia (AVNRT) ablations and from 43 to 28 min in the 71 atrial flutter (AFl) ablations (P<0.005 for both). In the 145 Wolff-Parkinson-White (WPW) ablations, a decrease from 27 to 23 min was observed (P=0.03). The decrease in AVNRT and AFl, but not in WPW was associated with the introduction of the LocaLisa system. CONCLUSION: The use of the LocaLisa system during RF ablations significantly reduced the fluoroscopy time in AVNRT and AFl ablations, by a median of 58% and 46%, respectively.

  • 35.
    Nilsson, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Ottander, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    The electrocardiographic reperfusion peak in patients with ST-elevation myocardial infarction.2007In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 41, no 1, p. 25-31Article in journal (Refereed)
  • 36.
    Ottander, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Nilsson, Johan 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.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Ischemic ST-segment episodes during the initial 24 hours of ST elevation myocardial infarction predict prognosis at 1 and 5 years2010In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 43, no 3, p. 224-229Article in journal (Refereed)
    Abstract [en]

    Continuous ST-segment monitoring during the first 24 hours of a myocardial infarction is a valuable tool for identifying high- and low-risk patients. The STC-VM events during 4 to 24 hours of the first day of a myocardial infarction predict mortality within 5 years.

  • 37. Rubulis, Aigars
    et al.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Lundahl, Gunilla
    Jensen, Jens
    Bergfeldt, Lennart
    Ischemia-induced repolarization response in relation to the size and location of the ischemic myocardium during short-lasting coronary occlusion in humans.2010In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 43, no 2, p. 104-112Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The ventricular repolarization (VR) response to short-lasting coronary occlusion has been characterized by 3-dimensional vectorcardiography (VCG) in humans; the T vector loop becomes distorted and more circular. The purpose of this study was to relate these changes to the size of the myocardium at risk (MAR) and its location. METHODS: Continuous VCG was applied during transient coronary occlusion in 35 elective angioplasty patients, and the size of the MAR was estimated by single-photon emission computed tomography. Three VR aspects were assessed at baseline vs maximum ischemia: the ST segment, the T vector angles, and the T vector loop morphology. RESULTS: The T loop morphology changes were significantly associated with MAR size, but also dependent of its location. In contrast, the early phase of VR reflected by the ST segment responded to acute ischemia in relation to the MAR size independent of location. CONCLUSION: The VR changes were related both to the size and the location of the MAR and most pronounced during occlusion of the left anterior descending artery.

  • 38.
    Rönn, Folke
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Kesek, Milos
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Höglund, Niklas
    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.
    Long-term follow-up of patients treated with ICD: benefit in patients with preserved left ventricular function.2008In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 42, no 2, p. 125-9Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Most major defibrillator trials have short follow-up and may neither capture the benefit for those with preserved function nor the progressive nature of advanced heart disease. We intended to investigate the long-term outcome in an unselected population of patients treated with ICD. DESIGN: We followed 124 consecutive patients that received an ICD during 1993-2002 at our institution for a median of 6.1 years. Information about heart disease, index arrhythmia, follow-up and death was extracted from medical records. RESULTS: The crude mortality was 26% (32/124). One- and two-year mortality was 6% and 12%, estimated 5- and 10-year mortality 20% and 33%. The cause of death was heart failure in 75% of deaths. The ejection fraction was below 35% in 91% of the 32 patients who died. We estimated that 28% of the patients received lifesaving therapy. The relative number of saved lives and complications was not related to the ejection fraction. CONCLUSION: Patients with preserved left ventricular function are excellent candidates for ICD, with life-saving ICD therapies in a substantial proportion, low mortality and good quality of life.

  • 39.
    Rönn, Folke
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Kesek, Milos
    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.
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Right ventricular lead positioning does not influence the benefits of cardiac resynchronization therapy in patients with heart failure and atrial fibrillation.2011In: Europace, ISSN 1099-5129, E-ISSN 1532-2092, Vol. 13, no 12, p. 1747-1752Article in journal (Refereed)
    Abstract [en]

    Aims Little is known about the optimal right ventricular (RV) pacing site in cardiac resynchronization therapy (CRT). This study compares bi-ventricular pacing at the left ventricular (LV) free wall combined with two different RV stimulation sites: RV outflow tract (RVOT+LV) vs. RV-apex (RVA+LV). Methods and results Thirty-three patients (32 males) with chronic heart failure, NYHA class III-IV, optimal drug therapy, QRS-duration ≥150 ms, and chronic atrial fibrillation (AF) received CRT with two different RV leads, in the apex (RVA) or outflow tract (RVOT), together with an LV lead, all connected to a bi-ventricular pacemaker. Randomization to pacing in RVOT+LV or RVA+LV was made 1 month after implantation and cross-over to the alternate pacing configuration occurred after 3 months. The median age of patients was 69 ± 10 years, the mean QRS was 179 ± 23 ms, and 58% of patients had ischaemic heart disease. Seven patients had pacemaker rhythm at inclusion and 60% were treated with atrioventricular-junctional ablation before randomization. In the RVA+LV and RVOT+LV pacing modes, 67 and 63% (nonsignificant) responded symptomatically with a decrease of at least 10 points in the Minnesota Living with Heart Failure score. The secondary end-points (6-min walk test, peak oxygen uptake, N-Terminal fragment of B-type Natriuretic Peptide, and left ventricular ejection fraction) showed significant improvement between baseline and CRT, but not between RVOT+LV and RVA+LV. Conclusion In this randomized controlled study, the exact RV pacing site, either apex or outflow tract, did not influence the benefits of CRT in a group of patients with chronic heart failure and AF. ClinicalTrials.gov ID: NCT00457834.

  • 40. Skanes, Allan C
    et al.
    Jensen, Steen
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Papp, Robert
    Li, Juliana
    Yee, Raymond
    Krahn, Andrew D
    Klein, George J
    Isolation of pulmonary veins using a transvenous curvilinear cryoablation catheter: feasibility, initial experience, and analysis of recurrences.2005In: J Cardiovasc Electrophysiol, ISSN 1045-3873, Vol. 16, no 12, p. 1304-8Article in journal (Refereed)
  • 41.
    Stattin, Eva-Lena
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Boström, Ida Maria
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Winbo, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Cederquist, Kristina
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Jonasson, Jenni
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Jonsson, Björn-Anders
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Diamant, Ulla-Britt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Norberg, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Founder mutations characterise the mutation panorama in 200 Swedish index cases referred for Long QT syndrome genetic testing2012In: BMC Cardiovascular Disorders, ISSN 1471-2261, E-ISSN 1471-2261, Vol. 12, p. 95-Article in journal (Refereed)
    Abstract [en]

    Background: Long QT syndrome (LQTS) is an inherited arrhythmic disorder characterised by prolongation of the QT interval on ECG, presence of syncope and sudden death. The symptoms in LQTS patients are highly variable, and genotype influences the clinical course. This study aims to report the spectrum of LQTS mutations in a Swedish cohort.

    Methods: Between March 2006 and October 2009, two hundred, unrelated index cases were referred to the Department of Clinical Genetics, Umea University Hospital, Sweden, for LQTS genetic testing. We scanned five of the LQTS-susceptibility genes (KCNQ1, KCNH2, SCN5A, KCNE1, and KCNE2) for mutations by DHPLC and/or sequencing. We applied MLPA to detect large deletions or duplications in the KCNQ1, KCNH2, SCN5A, KCNE1, and KCNE2 genes. Furthermore, the gene RYR2 was screened in 36 selected LQTS genotype-negative patients to detect cases with the clinically overlapping disease catecholaminergic polymorphic ventricular tachycardia (CPVT).

    Results: In total, a disease-causing mutation was identified in 103 of the 200 (52%) index cases. Of these, altered exon copy numbers in the KCNH2 gene accounted for 2% of the mutations, whereas a RYR2 mutation accounted for 3% of the mutations. The genotype-positive cases stemmed from 64 distinct mutations, of which 28% were novel to this cohort. The majority of the distinct mutations were found in a single case (80%), whereas 20% of the mutations were observed more than once. Two founder mutations, KCNQ1 p.Y111C and KCNQ1 p.R518*, accounted for 25% of the genotype-positive index cases. Genetic cascade screening of 481 relatives to the 103 index cases with an identified mutation revealed 41% mutation carriers who were at risk of cardiac events such as syncope or sudden unexpected death.

    Conclusion: In this cohort of Swedish index cases with suspected LQTS, a disease-causing mutation was identified in 52% of the referred patients. Copy number variations explained 2% of the mutations and 3 of 36 selected cases (8%) harboured a mutation in the RYR2 gene. The mutation panorama is characterised by founder mutations (25%), even so, this cohort increases the amount of known LQTS-associated mutations, as approximately one-third (28%) of the detected mutations were unique.

  • 42.
    Stattin, Eva-Lena
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Rydberg, Annika
    Jensen, Steen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    [Genetic testing for long QT syndrome is used in clinical practice]2006In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 103, no 45, p. 3542-Article in journal (Refereed)
  • 43.
    Sundström, Emilia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Diamant, Ulla-Britt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Implantable cardioverter defibrillator treatment in long QT syndrome patients: a national study on adherence to international guidelines2017In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 51, no 2, p. 88-94Article in journal (Refereed)
    Abstract [en]

    Objectives. Implantable cardioverter defibrillator (ICD) treatment is effective among long QT syndrome (LQTS) patients at a high risk of sudden cardiac death. Previous studies show that the international guidelines are not always followed, and that risk stratification may be based on genotype rather than individual risk profile. We analysed data from the Swedish ICD & Pacemaker Registry and medical records to examine how international guidelines were followed with regards to phenotype and genotype. Methods and results. ICD treatment was used in 150 Swedish LQTS patients from 1989-2013. The annual number of implantations increased over the study period. A total of 109 patients were included in the analysis. Most patients (91%) were symptomatic before the implantation. Seventy percent of patients who received ICD treatment met the 2006 Class I or Class IIa recommendations for LQTS treatment. Thirty-one percent of the LQT3 patients received ICD treatment despite being asymptomatic. Among LQT1 patients, 45% received ICD treatment after syncope despite beta-blockers. Conclusions. Thirty percent of Swedish LQTS patients with ICD received the treatment without a strong indication based on international guidelines. LQT3 patients were over-represented among asymptomatic patients. Many LQT1 patients received ICD despite the known effect of beta-blockers in this group.

  • 44. Vahedi, Farzad
    et al.
    Diamant, Ulla-Britt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Lundahl, Gunilla
    Bergqvist, Gabriel
    Gransberg, Lennart
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Bergfeldt, Lennart
    Instability of repolarization in LQTS mutation carriers compared to healthy control subjects assessed by vectorcardiography2013In: Heart Rhythm, ISSN 1547-5271, E-ISSN 1556-3871, Vol. 10, no 8, p. 1169-1175Article in journal (Refereed)
    Abstract [en]

    BACKGROUND Potassium channel dysfunction in congenital and acquired forms of long QT syndrome types 1 and 2 (LQT1 and LQT2) increases the beat-to-beat variability of the (IT interval. OBJECTIVE To study about the little known variability (instability) of other aspects of ventricular repolarization (VR) in humans by using vectorcardiography. METHODS Beat-to-beat analysis was performed regarding vectorcardiography derived RR, QRS, and QT intervals, as well as T vector- and T vector loop-based parameters during 1-minute recordings of uninterrupted sinus rhythm at rest in 41 adult LQT1 (n = 31) and LQT2 (n = 10) mutation carriers and 41 age- and sex-matched control subjects. The short-term variability for each parameter, describing the mean orthogonal distance to the line of identity on the Poincare plot, was calculated. RESULTS Mutation carriers showed significantly larger (by a factor 2) instability in most VR parameters compared to controls despite higher instantaneous heart rate variability (STVRR) in the control group. The longer the (IT interval, the greater was its instability, and the instability of VR dispersion measures. CONCLUSIONS A greater instability of most aspects of VR already at rest seems to be a salient feature in both LQT1 and LQT2, which might pave the way for early afterdepolarizations and torsades de pointes ventricular tachycardia. In contrast, no signs of increased VR dispersion per se were observed in mutation carriers.

  • 45. Vahedi, Farzad
    et al.
    Haney, Michael. F.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Jensen, Steen. M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Bergfeldt, Lennart
    Effect of heart rate on ventricular repolarization in healthy individuals applying vectorcardiographic T vector and T vector loop analysis2011In: Annals of Noninvasive Electrocardiology, ISSN 1082-720X, E-ISSN 1542-474X, Vol. 16, no 3, p. 287-294Article in journal (Refereed)
    Abstract [en]

    Background: Ventricular repolarization (VR) is strongly influenced by heart rate (HR) and autonomic nervous activity, both of which also are important for arrhythmogenesis. Their relative influence on VR is difficult to separate, but might be crucial for understanding while some but not other individuals are at risk for life-threatening arrhythmias at a certain HR. This study was therefore designed to assess the "pure" effect of HR increase by atrial pacing on the ventricular gradient (VG) and other vectorcardiographically (VCG) derived VR parameters during an otherwise unchanged condition. Methods: In 19 patients with structurally normal hearts, a protocol with stepwise increased atrial pacing was performed after successful arrhythmia ablation. Conduction intervals were measured on averaged three-dimensional (3D) QRST complexes. In addition, various VCG parameters were measured from the QRS and T vectors as well as from the T loop. All measurements were performed after at least 3 minutes of rate adaptation of VR. Results: VR changes at HR from 80 to 120 bpm were assessed. The QRS and QT intervals, VG, QRSarea, Tarea, and Tamplitude were markedly rate dependent. In contrast, the Tp-e/QT ratio was rate independent as well as the T-loop morphology parameters Tavplan and Teigenvalue describing the bulginess and circularity of the loop. Conclusions: In healthy individuals, the response to increased HR within the specified range suggests a decreased heterogeneity of depolarization instants, action potential morphology, and consequently of the global VR. Ann Noninvasive Electrocardiol 2011;16(3):287-294.

  • 46. Walfridsson, Håkan
    et al.
    Anfinsen, Ole-Gunnar
    Berggren, Anders
    Frison, Lars
    Jensen, Steen
    Department of Cardiology, University Hospital, Umeå, Sweden.
    Linhardt, Gunnila
    Nordkam, Ann-Christin
    Sundqvist, Monika
    Carlsson, Leif
    Is the acetylcholine-regulated inwardly rectifying potassium current a viable antiarrhythmic target?: Translational discrepancies of AZD2927 and A7071 in dogs and humans2015In: Europace, ISSN 1099-5129, E-ISSN 1532-2092, Vol. 17, no 3, p. 473-482Article in journal (Refereed)
    Abstract [en]

    Aims We aimed at examining the acetylcholine-dependent inward-rectifier current (I-KAch) as a target for the management of atrial fibrillation (AF). Methods and results The investigative agents AZD2927 and A7071 concentration-dependently blocked I-KAch in vitro with minimal off-target activity. In anaesthetized dogs (n -= 17) subjected to 8 weeks of rapid atrial pacing (RAP), the Left atrial effective refractory period (LAERP) was maximally increased by 50 +/- 7.4 and 50 +/- 4.8 ms following infusion of AZD2927 and A7071. Ventricular refractoriness and the QT interval were unaltered. During sustained AF, both drugs significantly reduced AF frequency and effectively restored sinus rhythm. AZD2927 successfully restored sinus rhythm at 10/10 conversion attempts and A7071 at 14/14 attempts, whereas saline converted 4/17 episodes only (P<0.001 vs. AZD2927 and A7071). In atrial flutter patients (n = 18) undergoing an invasive investigation, AZD2927 did not change LAERP, the paced QT interval, or ventricular refractoriness when compared with placebo. To address the discrepancy on LAERP by I-KAch blockade in man and dog and the hypothesis that atrial electrical remodelling is a prerequisite for &Act, blockade being efficient, six dogs were studied after 8 weeks of RAP followed by sinus rhythm for 4 weeks to reverse electrical remodelling. In these dogs, both AZD2927 and A7071 were as effective in increasing LAERP as in the dogs studied immediately after the 8-week RAP period. Conclusion Based on the present series of experiments, an important role of !1 in human atrial electrophysiology, as well as its potential as a viable target for effective management of AF, may be questioned.

  • 47.
    Wiklund, Urban
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    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.
    Abnormal heart rate variability and subtle atrial arrhythmia in patients with familial amyloidotic polyneuropathy2008In: Annals of Nonivasive Electrocardiology, Vol. 13, no 3, p. 249-256Article in journal (Refereed)
  • 48.
    Winbo, Annika
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Diamant, Ulla-Britt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Persson, Johan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Stattin, Eva-Lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Origin of the Swedish long QT syndrome Y111C/KCNQ1 founder mutation2011In: Heart Rhythm, ISSN 1547-5271, E-ISSN 1556-3871, Vol. 8, no 4, p. 541-547Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The Y111C/KCNQ1 mutation causes a dominant-negative effect in vitro albeit a benign clinical phenotype in a Swedish Long QT Syndrome population.

    OBJECTIVE: To investigate the origin (genealogic, geographic, genetic and age) of the Y111C/KCNQ1 mutation in Sweden.

    METHODS: We identified 170 carriers of the Y111C/KCNQ1 mutation in 37 Swedish proband families. Genealogical investigation was performed in all families. Haplotype analysis was performed in 26 probands, 21 family members and 84 healthy Swedish controls, using 15 satellite markers flanking the KCNQ1 gene. Mutation age was estimated using the ESTIAGE and DMLE computer softwares and regional population demographics data.

    RESULTS: All probands were traced back to a northern river valley region. A founder couple born in 1605/1614 connected 26/37 families. Haplotyped probands shared 2-14 (median 10) uncommon alleles, with frequencies ranging between 0.01-0.41 (median 0.16) in the controls. The age of the mutation was estimated to 24 generations (95% CI 18; 34), i.e. 600 years (95% CI 450; 850) if assuming 25 years per generation. The number of now living Swedish Y111C mutation-carriers was estimated to ~200-400 individuals for the mutation age span 22-24 generations and population growth rates 25-27%.

    CONCLUSIONS: The Y111C/KCNQ1 mutation is a Swedish LQTS founder mutation, introduced in the northern population approximately 600 years ago. The enrichment of the mutation was enabled by a mild clinical phenotype and strong regional founder effects during the population development of the northern inland. The Y111C/KCNQ1 founder population constitutes an important asset for future genetic and clinical studies.

  • 49.
    Winbo, Annika
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Diamant, Ulla-Britt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stattin, Eva-Lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Low incidence of sudden cardiac death in a Swedish Y111C type 1 long-QT syndrome population2009In: Circulation: Cardiovascular Genetics, ISSN 1942-325X, E-ISSN 1942-3268, Vol. 2, no 6, p. 558-564Article in journal (Refereed)
    Abstract [en]

    Background: A 10% cumulative incidence and a 0.3% per year incidence rate of sudden cardiac death in patients younger than 40 years and without therapy have been reported in type 1 long-QT syndrome. The Y111C-KCNQ1 mutation causes a severe phenotype in vitro, suggesting a high-risk mutation. This study investigated the phenotype among Y111C-KCNQ1 mutation carriers in the Swedish population with a focus on life-threatening cardiac events.

    Methods and Results: We identified 80 mutation carriers in 15 index families, segregating the Y111C-KCNQ1 mutation during a national inventory of mutations causing the long-QT syndrome. Twenty-four mutation carriers <40 years experienced syncope (30%). One mutation carrier had an aborted cardiac arrest (1.25%). No case of sudden cardiac death was reported during a mean nonmedicated follow-up of 25±20 years. This corresponds to a low incidence rate of life-threatening cardiac events (0.05%/year versus 0.3%/year, P=0.025). In 8 Y111C families connected by a common ancestor, the natural history of the mutation was assessed by investigating the survival over the age of 40 years for 107 nonmedicated ascertained mutation carriers (n=24) and family members (n=83) born between 1873 and 1968. In total, 4 deaths in individuals younger than 40 years were noted: 1 case of noncardiac death and 3 infant deaths between 1873 and 1915.

    Conclusions: The dominant-negative Y111C-KCNQ1 mutation, associated with a severe phenotype in vitro, presents with a low incidence of life-threatening cardiac events in a Swedish population. This finding of discrepancy emphasizes the importance of clinical observations in the risk stratification of long-QT syndrome.

  • 50.
    Winbo, Annika
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stattin, Eva-Lena
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Medical and Clinical Genetics.
    Diamant, Ulla-Britt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Persson, Johan
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Prevalence, mutation spectrum, and cardiac phenotype of the Jervell and Lange-Nielsen syndrome in Sweden2012In: Europace, ISSN 1099-5129, E-ISSN 1532-2092, Vol. 14, no 12, p. 1799-1806Article in journal (Refereed)
    Abstract [en]

    AIMS: To explore the national prevalence, mutation spectrum, cardiac phenotype, and outcome of the uncommon Jervell and Lange-Nielsen syndrome (JLNS), associated with a high risk of sudden cardiac death.

    METHODS AND RESULTS: A national inventory of clinical JLNS cases was performed. Genotype and area of origin were ascertained in index families. Retrospective clinical data were collected from medical records and interviews. We identified 19 cases in 13 Swedish families. A JLNS prevalence >1:200 000 was revealed (five living cases <10 years of age). The mutation spectrum consisted of eight KCNQ1 mutations, whereof p.R518X in 12/24 alleles. Geographic clustering of four mutations (20/24 alleles) and similarities to Norway's mutation spectrum were seen. A high prevalence of heterozygotes was suggested. Three paediatric cases on β-blockers since birth were as yet asymptomatic. Seven symptomatic cases had suffered an aborted cardiac arrest and four had died suddenly. QTc prolongation was significantly longer in symptomatic cases (mean 605 ± 62 vs. 518 ± 50 ms, P = 0.016). β-Blockers reduced, but did not abolish, cardiac events in any previously symptomatic case. β-Blocker type, dosage, and compliance probably affect outcome significantly. Implantable cardioverter-defibrillator therapy (ICD, n = 6) was associated with certain complications; however, no case of sudden death.

    CONCLUSION: Founder effects could explain 83% of the Swedish JLNS mutation spectrum and probably contribute to the high JLNS prevalence found in preadolescent Swedish children. Due to the severe cardiac phenotype in JLNS, the importance of stringent β-blocker therapy and compliance, and consideration of ICD implantation in the case of therapy failure is stressed.

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