Left ventricle functional geometry in cardiac pathology

Left ventricular functional geometry (LV FG) refers to the dynamical change in the ventricular shape during contraction and relaxation. It has been shown that LV FG significantly contributes to the regulation of contractility and cardiac pump function in health and disease. The aim of our work is to evaluate the LV FG in patients with common myocardial diseases. Here we have evaluated a control group of healthy people, patients with ischemic heart disease (IHD) with preserved ejection fraction (EF); patients with dilated cardiomyopathy (DCM) before and after cardiac resynchronization therapy (CRT). We used classical 2D apical four-chamber position in ultrasound video loop to evaluate the spatio-temporal heterogeneity of LV regional wall motion and dynamics of shape indexes (sphericity, conicity, shape-power index). We have shown that the LV FG characteristics in DCM patients significantly differed from the control and disturbances were more pronounced than that in IHD patients. It was shown a tendency in the recovery of the LV FG characteristics towards the control values along with an increase in the ejection fraction. The relative change in the sphericity index from diastole to systole, and both the end-systolic sphericity and shape-power indexes demonstrated a high diagnostic accuracy in determining CRT responding patients.