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Speckle Tracking (speckle + tracking)

Distribution by Scientific Domains

Medical Sciences	83%

Selected Abstracts

Aortic Valve Closure: Relation to Tissue Velocities by Doppler and Speckle Tracking in Patients with Infarction and at High Heart Rates

ECHOCARDIOGRAPHY, Issue 4 2010
Ph.D., Svein A. Aase M.Sc.
Aim: To resolve the event in tissue Doppler (TDI)- and speckle tracking-based velocity/time curves that most accurately represent aortic valve closure (AVC) in infarcted ventricles and at high heart rates. Methods: We studied the timing of AVC in 13 patients with myocardial infarction and in 8 patients at peak dobutamine stress echo. An acquisition setup for recording alternating B-mode and TDI image frames was used to achieve the same frame rate in both cases (mean 136.7 frames per second [FPS] for infarcted ventricles, mean 136.9 FPS for high heart rates). The reference method was visual assessment of AVC in the high frame rate narrow sector B-mode images of the aortic valve. Results: The initial negative velocities after ejection in the velocity/time curves occurred before AVC, 44.9 ± 21.0 msec before the reference in the high heart rate material, and 25.2 ± 15.2 msec before the reference in the infarction material. Using this time point as a marker for AVC may cause inaccuracies when estimating end-systolic strain. A more accurate but still a practical marker for AVC was the time point of zero crossing after the initial negative velocities after ejection, 5.4 ± 15.3 msec before the reference in high heart rates and 8.2 ± 12.9 msec after the reference in the infarction material. Conclusion: The suggested marker of AVC at high heart rate and in infarcted ventricles was the time point of zero crossing after the initial negative velocities after ejection in velocity/time curves. (Echocardiography 2010;27:363-369) [source]

Effect of Preload on Left Ventricular Longitudinal Strain by 2D Speckle Tracking

ECHOCARDIOGRAPHY, Issue 8 2008
Jin-Oh Choi M.D.
Background: Peak systolic longitudinal strain (PSLS) obtained using the 2D speckle tracking method is a novel indicator of the long-axis function of the left ventricle (LV). We used the 2D strain profile to examine the effect of preload reduction by hemodialysis (HD) on LV PSLS in patients with end-stage renal disease (ESRD). Method and results: Twenty-nine pairs of echocardiographic evaluations were obtained before and after dialysis. Global LV PSLS was ,18.4 ± 2.9%, at baseline and decreased to ,16.9 ± 3.2% after HD (P < 0.001). Segmental analysis showed that the decrease in PSLS after dialysis was most prominent in mid-LV segments (,17.1 ± 3.5% vs. ,15.4 ± 3.4%, P < 0.001). Conclusion: PSLS obtained from the 2D strain profile is a reliable parameter that may be useful for evaluating LV systolic long-axis function. However, PSLS should be applied cautiously in ESRD patients because it could be affected by dialysis. [source]

Aortic Valve Closure: Relation to Tissue Velocities by Doppler and Speckle Tracking in Patients with Infarction and at High Heart Rates

Association of Left Atrial Strain and Strain Rate Assessed by Speckle Tracking Echocardiography with Paroxysmal Atrial Fibrillation

ECHOCARDIOGRAPHY, Issue 10 2009
Wei-Chuan Tsai M.D.
Background: We hypothesized that contraction of the LA wall could be documented by speckle tracking and could be applied for assessment of LA function. This study tried to identify the association between LA longitudinal strain (LAS) and strain rate (LASR) measured by speckle tracking with paroxysmal atrial fibrillation (PAF). Methods: Fifty-two patients (61 ± 17 years old, 23 men) with sinus rhythm at baseline referred for the evaluation of episodic palpitation were included. Standard four-chamber and two-chamber views were acquired and analyzed off-line. Peak LAS and LASR were carefully identified as the peak negative inflection of speckle tracking waves after P-wave gated by electrocardiography. Results: Ten patients (19%) had PAF. LAS, LASR, age, left ventricular end-diastolic dimension, left ventricular mass, LA volume, and mitral early filling-to-annulus early velocity ratio were different between patients with and without PAF. After multivariate analysis, LASR was significantly independently associated with PAF (OR 8.56, 95% CI 1.14,64.02, P = 0.036). Conclusion: Speckle tracking echocardiography could be used in measurements of LAS and LASR. Decreased negative LASR was independently associated with PAF. [source]

Methods for prenatal assessment of fetal cardiac function

PRENATAL DIAGNOSIS, Issue 13 2009
Tim Van Mieghem
Abstract Fetal cardiac function is increasingly recognized as a marker of disease severity and prognosis in selected fetal conditions. Magnetic resonance imaging (MRI) has been used in experimental (animal) fetal cardiology but the lack of a noninvasive fetal electrocardiogram (ECG) to trigger image acquisition remains a major limiting factor precluding its application in humans. Fetal medicine specialists are therefore limited to ultrasound to evaluate human fetal cardiac function. In this review, we aim to provide a complete overview of the different ultrasound techniques that can be used for fetal cardiac function assessment and we discuss their (theoretical) strengths and shortcomings. Conventional methods include M-mode assessment of ventricular contractility and Doppler assessment of the precordial veins and cardiac output (CO). More recent techniques such as the measurement of the myocardial performance index (MPI), myocardial motion analysis with tissue Doppler, speckle tracking and three-dimensional (3D) ultrasound techniques are also discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Adaptative or maladaptative hypertrophy, different spatial distribution of myocardial contraction

CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2010
Francesco Cappelli
Summary Background:, Left ventricular hypertrophy (LVH) may be an adaptative remodelling process induced by physical training, or result from pathological stimuli. We hypothesized that different LVH aetiology could lead to dissimilar spatial distribution left ventricular (LV) contraction, and compared different components of LV contraction using 2-dimensional (2-D) speckle tracking derived strain in subjects with adaptative hypertrophy (endurance athletes), maladaptative hypertrophy (hypertensive patients) and healthy controls. Method:, We enrolled 22 patients with essential hypertension, 50 endurance athletes and 24 healthy controls. All subjects underwent traditional echocardiography and 2-D strain evaluation of LV longitudinal, circumferential and radial function. LV basal and apical rotation and their net difference, defined as LV torsion, were evaluated. Results:, LV wall thicknesses, LV mass and left atrium diameter were comparable between hypertensive group and athletes. LV longitudinal strain was reduced only in hypertensive patients (P < 0·05). LV apex circumferential strain was higher in hypertensive patients than in other groups (P < 0·001), LV basal circumferential strain, although slightly increased, did not reach significant difference. Hypertensive patients showed significantly increased rotation and torsion (P < 0·001), while no differences were observed between athletes and control. Conclusion:, In patients with pathological LVH, LV longitudinal strain was reduced, while circumferential deformation and torsion were increased. No differences were observed in LV contractile function between subjects with adaptative LVH and controls. In pathological LVH, increasing torsion could be considered a compensatory mechanism to counterbalance contraction and relaxation abnormalities to maintain a normal LV output. [source]