LV longitudinal and radial strains are reduced, but circumferential deformation and twist are normal in DHF patients. On the other hand, in patients with SHF, longitudinal, radial, and circumferential deformation, and twist are all reduced. Multivariable regression analysis suggests that preserved LV twist and circumferential strain may contribute to normal EF in patients with DHF.

Background-Diastolic strain rate (SR) measurements that comprise all left ventricular (LV) segments are advantageous over myocardial velocity for assessment of diastolic function. Mitral early diastolic velocity (E)/SR ratio during the isovolumetric relaxation (IVR) period can be used to estimate LV filling pressures. Methods and Results-Simultaneous echocardiographic imaging and LV pressure measurements (7F catheters) were performed in 7 adult dogs. Loading conditions were altered by saline infusion and caval occlusion, and lusitropic state was changed by dobutamine and esmolol infusion. A curve depicting global SR was derived from each of the 3 apical views, and SR was measured during IVR (SR IVR ) and early LV filling (SR E ). SR IVR had a strong correlation with time constant of LV pressure decay during the IVR period () (rϭϪ0.83, PϽ0.001), whereas SR E was significantly related to LV end-diastolic pressure (rϭ0.52, Pϭ0.005) in the experimental stages where was Ͻ40 ms. In 50 patients with simultaneous right heart catheterization and echocardiographic imaging, mitral E/SR IVR ratio had the best correlation with mean wedge pressure (rϭ0.79, PϽ0.001), as well as in 24 prospective patients (rϭ0.84, Pϭ0.001). E/SR IVR was most useful in patients with ratio of E to mitral annulus early diastolic velocity (E/Ea ratio) 8 to 15 and was more accurate than E/Ea in patients with normal ejection fraction and regional dysfunction (both PϽ0.01). Conclusions-Global SR IVR by 2-dimensional speckle tracking is strongly dependent on LV relaxation. E/SR IVR can predict LV filling pressures with reasonable accuracy, particularly in patients with normal ejection fraction and in those with regional dysfunction.

Apex-to-base delay in mechanical shortening of LV parallels the apex-to-base direction of the electric activation sequence. Basal subendocardial and apical subepicardial regions deform through a characteristic phase of postsystolic shortening. Short-lived apex-to-base and subendocardial-to-subepicardial relaxation gradients at the onset of diastole may have a physiologic significance in facilitating active restoration of the LV cavity in diastole.

Systolic dyssynchrony occurs in 33% of DHF patients, and diastolic dyssynchrony occurs in 58%. Medical therapy results in significant shortening of the diastolic intraventricular time delay which is closely related to improvement in LV relaxation.

Subendocardial and subepicardial layers of the left ventricle (LV) are characterized with right- and left-handed helical orientations of myocardial fibers. We investigated the origin of biphasic deformations of the LV wall during isovolumic contraction (IVC) and relaxation (IVR). In eight open-chest adult pigs, strain rates were measured along the right- and left-handed helical directions in the LV anterior wall by implanting 16 sonomicrometry crystals. Sonomicrometry strain rates were compared with the longitudinal subendocardial strain rates obtained by tissue Doppler imaging. During ejection and diastolic filling, shortening and lengthening occurred synchronously along the right- and left-handed helical directions. However, during IVC and IVR, the deformations were dissimilar in the two directions. Transmural shortening during IVC occurred along the right-handed helical direction and was accompanied with transient lengthening in the left-handed helical direction. Conversely, during IVR, the LV lengthened along the left-handed helical direction and shortened in the right-handed helical direction. Peak subendocardial strain rates obtained by tissue Doppler imaging during IVC and IVR correlated with corresponding sonomicrometry strain rate values obtained along the right- and left-handed helical directions (r = 0.81, P < 0.001 and r = 0.70, P = 0.001, respectively). Our data suggest that brief counterdirectional movements occur within the LV wall during IVC and IVR. Shortening along the right-handed helical direction is accompanied with reciprocal lengthening in the left-handed helical direction during IVC and vice versa during IVR. The results support an association between asynchronous deformation of subendocardial and subepicardial muscle fibers and the biphasic isovolumic movements observed with high-resolution tissue Doppler imaging.