Segmental and global myocardial work in hypertensive patients with different left ventricular ejection fraction: what's the role of the apex played?

Abstract

We investigated myocardial work in hypertension (HT) among patients with different left ventricular ejection fraction (LVEF) to analyze the contribution of segmental myocardial work to global myocardial work. 114 patients with HT were divided into 4 groups: HTsnEF ("supra-normal" EF, > 65%); HTnEF ("normal" EF, 60-65%); HTmEF (designed as "middle" EF, 50-60%, within an abnormal LV geometry); HTrEF (reduced EF, < 50%). Longitudinal strain (LS) and myocardial work indices were obtained by echocardiography: myocardial work index (MWI), constructive work (MCW), wasted work (MWW), myocardial work efficiency (MWE), and percentages of apical work were calculated (P_Api-MWI, P_Api-MCW). Global LS (GLS) and global MWE (GWE) decreased in HTmEF and HTrEF groups. Global MWI(GWI) and MCW(GCW) increased in HTsnEF and HTnEF groups, and subsequently decreased, particularly in HTrEF group (P < 0.05). GWW increased in all HT subgroups. All segmental MWI and MCW were elevated or preserved initially in HTsnEF and HTnEF groups, and subsequently decreased, obviously in basal and middle segments in HTrEF group (P < 0.05). All segmental MWW increased and MWE decreased in HTmEF and HTrEF groups (P < 0.05). P_Api-MWI and P_Api-MCW increased initially, and subsequently decreased in HTmEF group, and elevated significantly in HTrEF group. Correlation analysis revealed a close connection of GLS and myocardial work parameters with LVEF. Apical myocardial work increased at the early stages of hypertensive systolic dysfunction, as a compensatory mechanism. Segmental myocardial work analysis added value to explore the distribution of myocardial impairment.