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  • 1.
    Bajraktari, Gani
    et al.
    Second Division of Cardiology, University Clinical Centre of Kosova, Prishtina, Kosovo.
    Duncan, Alison
    Pepper, John
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Prolonged total isovolumic time predicts cardiac events following coronary artery bypass surgery2008In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 9, no 6, p. 779-783Article in journal (Refereed)
    Abstract [en]

    AIMS: Left ventricular (LV) systolic dysfunction may be associated with compromised stroke volume, which may be caused by asynchrony, reflected on the prolongation of isovolumic time (t-IVT). To assess the prognostic role of Doppler echocardiographic measurements in predicting cardiac events after coronary artery bypass grafting (CABG).

    METHODS AND RESULTS: The study included 74 patients undergoing routine CABG. A pre-CABG Doppler echocardiographic assessment of LV dimensions, filling and ejection was performed and t-IVT was determined as [60 - (total ejection time + total filling time)]. Follow-up period was 18 +/- 12 months. Of the 74 patients (age 65 +/- 16 years, 59 males), 29 underwent hospital admission for a cardiac event or died. There were no differences in age, gender, incidence of previous infarct or mitral regurgitation, LV-EDD (left ventricular end-diastolic dimension), left atrial or right ventricular size in patients with cardiac events compared with those without events. Left ventricular end-systolic dimension (LV-ESD) was greater (4.5 +/- 0.9 vs. 3.9 +/- 0.9 cm, P = 0.003), fractional shortening (FS) was lower (21 +/- 4 vs. 32 +/- 8%), E:A ratio and Tei index were higher (2.1 +/- 0.8 vs. 1.0 +/- 0.6 and 0.9 +/- 0.3 vs. 0.6 +/- 0.3, all P < 0.001), and t-IVT was longer (16 +/- 5 vs.10 +/- 4 s/min, P < 0.001) in patients with events. Multivariate predictors of post-CABG events (odds ratio 95% confidence interval) were low FS [0.66 (0.50-0.87), P < 0.001], high E:A ratio [l4.13 (1.17-14.60), P = 0.028], large LV-ESD [0.19 (0.05-0.84), P = 0.029], and long t-IVT [1.37 (1.02-1.84), P = 0.035].

    CONCLUSION: Despite satisfactory surgical revascularization, long t-IVT and systolic dysfunction suggest persistent ventricular dyssynchrony that contributes to post-CABG cardiac events. Early assessment of such patients for potential benefit from electrical resynchronization may optimize their cardiac performance and hence clinical outcome.

  • 2.
    Bukachi, Frederich
    et al.
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Waldenström, Anders
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Henein, M Y
    Kazzam, Elsadig
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Medicine.
    Pulmonary venous flow reversal and its relationship to atrial mechanical function in normal subjects--Umeå General Population Heart Study.2005In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 6, no 2, p. 107-116Article in journal (Refereed)
    Abstract [en]

    AIMS: Although pulmonary venous flow reversal (Ar) is useful in the evaluation of left ventricular (LV) diastolic function, it is often difficult to study with transthoracic echocardiography (TTE). We determined the relationship between Ar and left atrial (LA) mechanical function and sought to define surrogate measurements for Ar. METHODS AND RESULTS: A total of 130 healthy subjects, mean age 54.3+/-18.3 years, 62 women, were studied and classified into three groups: [young (Y), 25-44 years; n=44], [middle-age (M), 45-64 years; n=43] and [elderly (E), > or =65 years; n=43]. Pulmonary venous flow and LV inflow studies were performed by TTE and LV basal free-wall motion was studied by Doppler tissue imaging (DTI). All images were acquired with a superimposed electrocardiogram. RR interval was similar in all groups while LA dimension and PR interval were increased in Group E vs. Y (P<0.001). LA contraction (A(m)) on DTI, transmitral A-wave (A) and Ar were simultaneous and started 84ms after onset of P wave and this interval increased with age (P=0.02). Similarly, the time intervals from the same landmark to peak A(m), A, and Ar were prolonged with age (all, P<0.001). Despite this prolongation, peak A(m) coincided with peak Ar in every age group (r=0.97, P<0.001) and Ar acceleration and deceleration times were consistently equal. CONCLUSION: The timing of A(m) obtained by DTI can be used to accurately estimate corresponding measurements of Ar recorded by TTE in subjects without cardiac disease.

  • 3.
    Bukachi, Frederick
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Waldenström, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Kazzam, Elsadig
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Age dependency in the timing of mitral annular motion in relation to ventricular filling in healthy subjects: Umea General Population Heart Study2008In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 9, no 4, p. 522-529Article in journal (Refereed)
    Abstract [en]

    AIMS: Peak left ventricular (LV) relaxation normally precedes peak filling (E), which supports the hypothesis that LV suction contributes to early-diastolic filling. The significance of similar temporal discordance in late diastole has previously not been studied. We describe the time relationships between mitral annular motion and LV filling in early and late diastole and examine the effect of normal ageing on these time intervals. METHODS AND RESULTS: A total of 128 healthy subjects aged 25-88 years were studied. Transmitral and pulmonary venous flow reversals (Ar) were recorded by Doppler echocardiography. Mitral annular diastolic displacement-early (E(m)) and late (A(m))-were recorded by Doppler tissue imaging. With reference to electrocardiographic R and P-waves, the following measurements were made: R to peak E-wave (R-E) and E(m) (R-E(m)); onset P to peak A-wave (P-pA), A(m) (P-pA(m)), and Ar (P-pAr). The differences between [(R-E) and (R-E(m))] for early-diastolic temporal discordance (EDTD) and [(P-A) and (P-A(m))] for late-diastolic temporal discordance (LDTD) were calculated. Isovolumic relaxation time (IVRT) was also measured. Early-diastolic temporal discordance was approximately 26 ms in all age groups. Late-diastolic temporal discordance, however, was inversely related to age (r = -0.35, P < 0.001) and IVRT (r = -0.34, P < 0.001) and therefore decreased in the elderly vs. young (13 +/- 10 vs. 23 +/- 10 ms; P < 0.001). In multivariate analysis, age failed to predict LDTD in the presence of IVRT. A, A(m), and Ar were simultaneous at onset, and peak A(m) coincided with peak Ar in all age groups (r = 0.97, P < 0.001). No significant differences were noted in the RR intervals. CONCLUSIONS: Sequential prolongation of IVRT with ageing reduces LDTD, thus converging the peaks of A(m), A, and Ar (atrial mechanical alignment)-a potential novel method to identify subjects at increased dependency on atrial contraction for late-diastolic filling.

  • 4. Galderisi, Maurizio
    et al.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    D'hooge, Jan
    Sicari, Rosa
    Badano, Luigi P
    Zamorano, Josè Luis
    Roelandt, Jos R T C
    Recommendations of the European Association of Echocardiography: how to use echo-Doppler in clinical trials2011In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 12, no 5, p. 339-353Article in journal (Refereed)
    Abstract [en]

    The European Association of Echocardiography (EAE) has developed the present recommendations to assist clinical researchers in the design, implementation, and conduction of echocardiographic protocols for clinical trials and to guarantee their quality. Clinical trials should be designed and conducted based on the knowledge of the pathophysiology of the clinical condition studied, the technical characteristics of the echo-Doppler modalities, and the variability of the tested parameters. These procedures are important to choose the most reliable and reproducible techniques and parameters. Quality assurance must be guaranteed by adequate training of peripheral site operators to obtain optimal echo-Doppler data and by using a core laboratory for accurate and reproducible data analysis.

  • 5.
    Gustafsson, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Mörner, Stellan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Waldenström, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Assessment of regional rotation patterns improves the understanding of the systolic and diastolic left ventricular function: an echocardiographic speckle-tracking study in healthy individuals2009In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, no 10, p. 56-61Article in journal (Refereed)
    Abstract [en]

    AIM To elucidate the complexity of left ventricular motion throughout the cardiac cycle, we studied regional rotation in detail. METHODS AND RESULTS: Regional rotation in six subdivisions of the circumference at three levels was studied by using speckle-tracking echocardiography in 40 healthy subjects. At the basal level the inferoseptal segments rotated significantly more clockwise during systole than the opposing anterolateral segments. At the papillary level the inferoseptal segments differed significantly from the anterolateral segments, where the inferoseptal segments rotated clockwise and the anterolateral segments rotated counter-clockwise. The apical level showed significant difference in regional rotation only at aortic valve opening. In early systole, untwist before the main systolic twist was seen at the basal and apical levels; however, the duration of the basal untwist was much longer than that of the apical. The diastolic phases of rotation at the basal and apical levels matched the different filling phases. CONCLUSION: Large regional differences in rotation are present at the basal and papillary levels in healthy subjects. The diastolic untwist matches the phases of both the E-wave and A-wave and seems to be related with intraventricular pressure differences, indicating that untwist plays an important role in the filling of the ventricle.

  • 6.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Right ventricular outflow-tract fractional shortening: an applicable measure of right ventricular systolic function.2003In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114Article in journal (Refereed)
  • 7.
    Lindqvist, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Bajraktari, Gani
    Molle, Roberta
    Palmerini, Elizabetta
    Holmgren, Anders
    Mondillo, Sergio
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Valve replacement for aortic stenosis normalizes subendocardial function in patients with normal ejection fraction.2010In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114Article in journal (Refereed)
    Abstract [en]

    AIMS: Long-standing aortic stenosis (AS) causes various degrees of left ventricular (LV) dysfunction, which may improve after valve replacement. The aim of this study was to assess the nature of LV subendocardial abnormalities in AS and their response to valve replacement (AVR). METHODS AND RESULTS: We studied 41 consecutive symptomatic patients (age 64 +/- 13 years) with severe AS, normal LV ejection fraction (EF), but no obstructive coronary artery disease before, a week after AVR, and 6 months after AVR. LV subendocardial function was studied from recordings of long-axis M-mode (amplitude), tissue-Doppler (myocardial velocities) and speckle tracking (myocardial strain) echocardiographic techniques. Results were compared with those from 20 age- and gender-matched controls. In patients, LV dimensions and markers of asynchrony, total isovolumic time (t-IVT), and Tei index were not different from controls before AVR and remained unchanged afterwards. LV lateral long-axis amplitude, as well as lateral and septal systolic velocities and strain, were reduced (P < 0.001 for all) and E/E' was modestly raised. Lateral long-axis amplitude, systolic and diastolic velocities normalized within a week of AVR but strain lagged behind until 6 months later. The reduced septal long-axis amplitude remained permanently unchanged (NS) despite the early normalization of its systolic velocities (P < 0.001) and strain (P < 0.001). LV mass normalized at 6 months after AVR (P < 0.005). CONCLUSIONS: In patients with severe AS and maintained LV ejection fraction, subendocardial function is globally abnormal showing reduced amplitude of motion, velocities, and strain. The different response of its components suggests an evidence for differential reverse remodelling, irrespective of myocardial mass regression.

  • 8.
    Lindqvist, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Calcutteea, Avin
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Echocardiography in the assessment of right heart function.2008In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 9, no 2, p. 225-234Article in journal (Refereed)
  • 9.
    Lindqvist, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Right ventricular outflow-tract fractional shortening: an applicable measure of right ventricular systolic function.2003In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114Article in journal (Refereed)
  • 10.
    Lindqvist, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Sundsvall Hospital, Sundsvall.
    Henein, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Royal Brompton Hospital, London.
    Kazzam, Elsadig
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Mälar Hospital, Eskilstuna.
    Right ventricular outflow-tract fractional shortening: an applicable measure of right ventricular systolic function.2003In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 4, no 1, p. 29-35Article in journal (Refereed)
    Abstract [en]

    AIMS: Assessment of right ventricular function is important. However, this is not easy to achieve due to the complex anatomy and geometry of the right ventricle, making the evaluation of its function limited. Therefore, a simple reliable and easy method is needed. This study was performed (1) to evaluate the use of right ventricular outflow tract fractional shortening obtained by M-mode echocardiography as a measure of right ventricular systolic function and (2) to determine the relationship between this parameter and other established measurements of right ventricular function such as long axis excursion.

    METHODS AND RESULTS: Ninety-two consecutive patients referred for echocardiographic assessment of left and right ventricular function, age mean+/-SD was 68+/-14 years, were investigated. Twenty healthy controls, age 46+/-12 years were also studied. M-mode echocardiography was used to measure right ventricular outflow tract fractional shortening and right ventricular long axis excursion. Doppler echocardiography was used for the estimation of right ventricular-right atrial pressure drop and pulmonary artery acceleration time. Right ventricular outflow tract fractional shortening (P<0.0001), right ventricular long axis excursion (P<0.0001) and pulmonary acceleration time (P<0.0001) were reduced in patients compared to controls. Right ventricular outflow tract fractional shortening correlated with long axis excursion (r=0.66 P<0.0001), pulmonary artery acceleration time (r=0.80 P<0.0001) and right ventricular-right atrial pressure drop (r=-0.53 P<0.0001). Right ventricular long axis excursion correlated with right ventricular-right atrial pressure drop though to a lesser significance (r=-0.27 P <0.001). Furthermore, right ventricular outflow tract fractional shortening was reduced in patients with pulmonary hypertension compared to patients without, this difference was not observed in the right ventricular systolic long axis excursion.

    CONCLUSION: Right ventricular outflow tract fractional shortening provides a simple and non-invasive measure of right ventricular systolic function. In combination with long axis excursion and Doppler velocities they should provide comprehensive assessment of right ventricular function.

  • 11.
    Lindqvist, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Söderberg, Stefan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Gonzalez, Manuel Garcia
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Tossavainen, Erik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Echocardiography based estimation of pulmonary vascular resistance in patients with pulmonary hypertension: a simultaneous Doppler echocardiography and cardiac catheterization study2011In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 12, no 12, p. 961-966Article in journal (Refereed)
    Abstract [en]

    Aims: Pulmonary vascular resistance (PVR) is an important measurement for the diagnosis of patients with pulmonary hypertension (PH) but needs accurate determination of mean pulmonary artery pressure (PAMP). We aimed to test the accuracy of a Doppler-derived measurement of PVR, using the conventional invasive equation in patients with PH.

    Methods and results: We investigated 30 patients undergoing right heart catheterization (RHC), mean age 62 ± 13 years, 21 females, with different diseases; idiopathic pulmonary arterial hypertension (PAH) (n= 5), associated PAH (n= 16), chronic thromboembolic PH (n= 6), interstitial lung disease (n= 2), and after closure of an atrial septal defect (n= 1). Patients with impaired left ventricular systolic function (EF < 50%) or elevated pulmonary capillary wedge pressure (PCWP >15 mmHg on RHC) were excluded. We used the formula: PAMP = PASPecho × 0.61 + 2 mmHg, where PASPecho is the peak tricuspid regurgitation pressure drop + 10 or 7 mmHg. Pulmonary vascular resistance was then calculated as PAMPecho− PCWP/cardiac output. Pulmonary capillary wedge pressure was estimated at 10 mmHg in all cases. The Doppler-derived estimation of PVRecho was achievable in 90% of patients, in whom accurate calculation of PAMP was obtainable. Pulmonary vascular resistance echo individual values strongly correlated with those from RHC (r= 0.85, P< 0.001 and r= 0.87, P< 0.001 for the two estimated values for right atrial pressure, respectively). The regression equation using this formula was PVRrhc = 0.95 × PVRecho− 0.29, and the regression line was close to identity. The Bland–Altman plot showed a good agreement between PVRecho and PVRrhc values, with a mean difference of −0.66 ± 2.1 Wood unit.

    Conclusion: The proposed Doppler-derived formula for estimating PVR based on the conventionally used invasive equation strongly correlates with invasive gold standard measures.

  • 12.
    Lindqvist, Per
    et al.
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Waldenström, Anders
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine.
    Wikström, Gerhard
    Kazzam, Elsadig
    The use of isovolumic contraction velocity to determine right ventricular state of contractility and filling pressures A pulsed Doppler tissue imaging study.2005In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Eur J Echocardiogr, Vol. 6, no 4, p. 264-270Article in journal (Refereed)
    Abstract [en]

    AIMS: Echocardiographic techniques have not so far been able to provide a good estimation of myocardial contractility in humans. Myocardial motion during the isovolumic contraction phase, measured by Doppler tissue imaging, has only recently in experimental models been shown to describe myocardial contractility. The aim of the present clinical study was to investigate the relationship between right ventricular isovolumic contraction velocity and right ventricular state of contractility. METHODS AND RESULTS: Doppler tissue imaging and cardiac catheterization were performed simultaneously in 26 consecutive patients with different cardiac diseases (18 males, mean age 52 +/- 12, range 23-75 years). Peak isovolumic contraction velocity was measured using Doppler tissue imaging at 2 levels of the right ventricular free wall. During cardiac catheterization, the first derivative of right ventricular pressure related to the pulmonary artery peak pressure (dP/dt/P(max)) was measured. Furthermore, right ventricular end diastolic pressure, right atrial mean pressure, pulmonary artery systolic pressure, and pulmonary artery resistance, were also measured. A significant relationship was found between isovolumic contraction velocity and dP/dt/P(max) (r = 0.59, p < 0.01). This relationship was strengthened after excluding patients with elevated right atrial pressures (r = 0.77, p < 0.001). Furthermore, a correlation was also found between basal and mid cavity isovolumic contraction velocity and right ventricular end diastolic pressure (r = -0.47, r = -0.49, p < 0.05) as well as right atrial mean pressure (r = -0.63, r = -0.55, p < 0.01). CONCLUSION: Isovolumic contraction velocity is a reproducible and easily obtainable non-invasive parameter which correlates with invasive measurements of right ventricular state of contractility and right ventricular filling pressures.

  • 13. Zhao, Ying
    et al.
    Li, Zhi-An
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    PDA with Eisenmenger complicated by pulmonary artery dissection.2010In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114Article in journal (Refereed)
    Abstract [en]

    A 49-year-old lady, known to have Eisenmenger PDA, careful transthoracic echocardiogram, showed clear evidence for pulmonary trunk dissection with a flap across the pulmonary trunk and this finding was confirmed by a CT scan.

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