Left Ventricular Energy Loss Assessed by Vector Flow Mapping in Patients with Prediabetes and Type 2 Diabetes Mellitus

Abstract

The aim of this study was to assess left ventricular (LV) energy loss (EL) using vector flow mapping in patients with prediabetes (pre-DM) and type 2 diabetes mellitus (DM). Thirty pre-DM patients, 51 DM patients, and 38 controls were studied by transthoracic echocardiography. EL-total, EL-base, EL-mid and EL-apex climaxed at different phases. Compared with controls, pre-DM and DM patients showed increased EL-total during slow ejection, isovolumic relaxation, rapid filling and slow filling (p < 0.05). Similarly, EL-base, EL-mid and EL-apex increased during certain phases. Stepwise multiple regression analysis revealed that the early transmitral valve blood flow velocity E, the late transmitral valve blood flow velocity A, the ratio of E/A, LV peak torsion, diastolic untwisting velocity, vortex circulation and area were independently associated with EL during different phases (all p < 0.05). Our study suggests that LV EL is increased during diastole and certain phases of systole in DM patients compared with controls. The changes in LV vortex and deformation mechanics were correlated with EL.

Keywords: Diabetes mellitus; Echocardiography; Energy loss; Left ventricle; Vector flow mapping.