Comparison of left ventricular energy loss between patients with hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy

Objective To evaluate left ventricular energy loss (EL) in patients with hypertrophic cardiomyopathy (HCM) and hypertensive left ventricular hypertrophy (H-LVH) using vector flow map (VFM). Methods Twenty-five HCM patients, 21 H-LVH patients and 36 healthy subjects were selected as HCM group, H-LVH group and control group respectively in Zhongshan Hospital Fudan University. Color Doppler imaging of long-axis view loops were recorded for VFM analysis. According to the opening and closing of the aortic valve and mitral valve, isovolumic contraction (IVC), isovolumic relaxation (IVR), ejection period (EP) and filling period (FP) were determined. The total left ventricular EL(T-EL), IVC-EL, IVR-EL, EP-EL and FP-EL as well as peak EL during EP and FP were quantified. The measurement results were taken as the average of three cardiac cycles. Results ①Compared to the control group, FP-PEL was decreased in both patient groups, and HCM group was the lowest (P<0.05). Compared to the control group, EP-EL and EP-PEL were increased, while FP-EL was decreased in HCM group (all P<0.05); IVC-EL, EP-PEL, and EP-EL were increased in H-LVH group (all P<0.05). ②Compared with HCM group, the IVC-EL, FP-PEL, IVR-EL and FP-EL of H-LVH were higher(all P<0.05). ③The ROC analysis of five parameters with statistical difference between HCM group and H-LVH group showed that FP-EL and IVC-EL were more effective in the differential diagnosis of HCM and H-LVH. Conclusions Patients with cardiac hypertrophy and normal LVEF have increased systolic EL and reduced diastolic EL. H-LVH patients have more energy loss than HCM patients.EL might be a sensitive and valuable parameter to distinguish cardiac hypertrophy of different etiologies. Key words: Echocardiography; Ventricular function, left; Energy loss; Hypertrophic cardiomyopathy; Hypertension