2D speckle tracking echocardiography demonstrated that at end-systole, longitudinal and circumferential shortening and local twist angle significantly increased towards the apex (P<0.05).
Observational (n=12)
This study characterizes the normal physiological mechanics of the left ventricle during isovolumetric contraction and ejection using 2D speckle tracking echocardiography, demonstrating regional shortening, untwist, and spherical geometric changes.
p-value: p=<0.05
PURPOSE: The main purpose of the this human study was by speckle tracking imaging to characterize the regional and temporal distribution of normal left ventricular (LV) deformation and the LV geometry during isovolumetric contraction (IVC) and the ejection phase. METHODS: Twelve healthy young men 22 (2·3) years were included. Longitudinal and circumferential strain and local twist angle were measured at four LV short-axis levels: basal, papillary, subpapillary and apical level during IVC and ejection phases. In addition, LV length from apex to the atrio-ventricular level, two diameters at LV basal short-axis level and atrio-ventricular plane displacement (AVPD) were measured to characterize LV shape during IVC. RESULTS: During IVC, longitudinal and circumferential shortening was demonstrated at all four short-axis levels from base to apex, while the LV made a basal counterclockwise and apical clockwise rotation representing untwist. In addition, there was a reduction in LV length and changes in short-axis diameters at basal level and AVPD from end-diastole to end-IVC, reflecting that the LV changed from an oval to a more spherical shape. At end-systole, longitudinal and circumferential shortening and local twist angle were significantly increased towards apex (P<0·05). CONCLUSION: This study demonstrated that the IVC in healthy humans is characterized by regional longitudinal and circumferential shortening and LV untwist, which occurs parallel to geometric changes of the LV into a spherical shape. During ejection, increased regional gradients of LV deformation towards apex in LV longitudinal and circumferential shortening and local and net twist angle were demonstrated.
Hodt et al. (Fri,) conducted a observational in Healthy (n=12). 2D speckle tracking echocardiography was evaluated on Longitudinal and circumferential strain and local twist angle at four LV short-axis levels (p=<0.05). 2D speckle tracking echocardiography demonstrated that at end-systole, longitudinal and circumferential shortening and local twist angle significantly increased towards the apex (P<0.05).