Abstract

Objective To evaluate regional and global left ventricular (LV) function and LV wall thickness (WT) in patients with hypertrophic cardiomyopathy (HCM).

Design and Setting Observational study at the National Cardiovascular Center and Nagoya University Hospital in Japan.

Participants Thirty-six HCM patients and 16 patients with hypertensive LV hypertrophy (H-LVH).

Main Outcome Measures Conventional echocardiography and strain rate (SR) imaging derived from tissue Doppler imaging were performed. Systolic strain (∊_sys), peak systolic SR (SR_sys), peak early diastolic SR (SR_dia), and LVWT were obtained from eight LV segments. LV pressure was simultaneously recorded with a high-fidelity micromanometer.

Results The regional ∊_sys and SR_sys were correlated with LVWT in HCM patients (r = 0.50, p < 0.0001 and r = 0.63, p < 0.0001, respectively) but not in H-LVH patients. The standard deviations of LVWT, ∊_sys, and SR_sys obtained from the eight LV segments of each subject were greater for HCM patients than for H-LVH patients. The standard deviation of LVWT was correlated with those of ∊_sys and SR_sys (r = 0.55, p < 0.001 and r = 0.56, p < 0.001, respectively). The standard deviations of LVWT, ∊_sys, and SR_sys were correlated with tau (r = 0.35, p < 0.05; r = 0.47, p < 0.0005; and r = 0.39, p < 0.005, respectively).

Conclusions Heterogeneity of regional LV systolic function detected by SR imaging is in part attributable to heterogeneity of LV hypertrophy and may be linked to impaired global LV relaxation in HCM.