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Introduction Left ventricular (LV) twist is believed to store potential energy and plays an important role in generating diastolic suction. Recent advances in echocardiography techniques have allowed quantification of LV twist. The aim of the present study was to compare LV twist and torsion in healthy human subjects determined by velocity vector imaging (VVI) and tissue Doppler imaging (TDI) at rest. Materials and Methods All volunteers (72 healthy subjects) underwent complete echocardiographic study and LV torsional parameters were assessed using VVI or TDI methods. LV rotation at apical and basal short-axis levels was calculated throughout cardiac cycle and LV twist was defined as net difference between rotation angles of the two levels. The LV torsion was calculated as the LV twist divided by the LV end-diastolic length. Results Twist degree was significantly lower in the VVI group than the TDI group (11.4±2.4° vs.14.1±3.0°, p<0.001), but when LV twist was normalized by LV end-diastolic length, there was no statistically significant difference between the two groups (1.9±0.7°/cm vs. 2.1±0.6°/cm, p=0.142). Conclusion Normalized LV twist or LV torsion values were comparable for both imaging techniques (TDI and VVI methods). Results suggest that these methods may be interchanged for serial assessment, but needs additional studies and preferably larger populations to confirm it. [ABSTRACT FROM AUTHOR]

Background: More diagnostic techniques require a better understanding of the forces and stresses developed in the wall of the left ventricle. The aim of this study was to differentiate significant coronary artery disease (CAD) patients using a noninvasive quantification of myocardial wall stress in the diastole phase. Methods: Sixty male subjects with sinus rhythm (30 patients with significant and 30 with moderate left anterior descending coronary artery stenosis in the proximal portion) as well as 35 healthy subjects as the control group were recruited into the present study. By two-dimensional, pulsed wave, and tissue Doppler echocardiography, the average end-diastolic wall stress was calculated at the left ventricle anterior and interventricular septum wall segments using regional wall thickness, meridional and circumferential radii, and non-invasive left ventricular end-diastolic pressure. Results: A comparison of the calculated end-diastolic myocardial wall stress between the patients with significant and moderate coronary stenosis on the one hand and the healthy subjects on the other showed statistically significant differences in the anterior and septum wall segments (p value < 0.05). The patients with significant left anterior descending coronary artery stenosis had higher end-diastolic myocardial wall stress than did those with moderate stenosis and the healthy group in all the anterior and septum wall segments. Conclusion: It is concluded that non-invasive end-diastolic myocardial wall stress in coronary artery disease patients is an important index in evaluating myocardial performance. [ABSTRACT FROM AUTHOR]

Background: This study was undertaken to evaluate early-diastolic annular velocity (Ea) by color-TDI, combined with the early transmitral filling velocity (E) by pulsed Doppler echocardiography for estimation of left ventricular end diastolic pressure (LVEDP). We applied LVEDP to noninvasive quantification of myocardial wall stress in end-diastole. Forty-one coronary artery disease (CAD) patients with sinus rhythm underwent echocardiography and cardiac catheterization evaluated in the study. Methods: First linear regression analysis was performed to assess the relationships between E/Ea and LVEDP. Second LVEDP estimation with these two methods was tested prospectively in 59 additional CAD patients, and average end-diastolic wall stress was calculated at rest by measuring the principal radii, the thickness of the LV segments, and the estimated LVEDP. The results were compared to the wall stress that was calculated using catheter-measured LVEDP. Linear regression analysis was performed to assess the relationships between calculated wall stress using Doppler-estimated LVEDP (WSEP) and calculated wall stress using catheter-measured LVEDP (WSMP). Results: The results showed that LVEDP had a strong correlation to the lateral E/Ea (r = 0.85; P < 0.001) and medial E/Ea ratios (r = 0.73; P < 0.001). No significant differences were found between the WSEP and WSMP. There were highly significant correlations (at least r = 0.85, P < 0.001) between the WSMP and WSEP at all the myocardial sites. Conclusions: The current data demonstrate that the lateral E/Ea ratio obtained by Doppler echocardiography and color-TDI is a powerful estimator of LVEDP in CAD patients and provides pressure information required for noninvasive quantification of LV myocardial wall stress with reasonable accuracy in diastole. [ABSTRACT FROM AUTHOR]