Risk reduction after regression of echocardiographic left ventricular hypertrophy in hypertension: a meta-analysis.

BACKGROUND: The prognostic relevance of echocardiographic left ventricular hypertrophy (LVH) regression in hypertension is uncertain. The aim of this study was to perform an updated meta-analysis about the impact of LVH regression on the occurrence of cardiovascular events in hypertensive patients.
METHODS: We searched for studies on echocardiographic LVH regression and prognosis in hypertension that compared patients with or without LVH regression or groups including subjects with or without LVH regression and reported adjusted hazard ratio (HR) for calculating the overall effect size.
RESULTS: Five studies were identified (3,149 patients, mean age range 48-66 years, 58% men). Follow-up echocardiography was performed after a mean period ranging from 1 to 5 years. Entire follow-up duration ranged from 3 to 9 years. Globally, 333 cardiovascular events occurred. Three whole studies and subgroups of two others were included in the meta-analysis, comprising 2,449 patients, 1,900 (78%) with baseline LVH and 969 (51%) with LVH regression, who experienced 304 events. The overall adjusted HR of total cardiovascular events was 0.54, 95% confidence interval (CI) 0.35-0.84, P = 0.007, for LVH regression/persistent normal left ventricular (LV) mass vs. LVH persistence/LVH development. Heterogeneity was found between studies. Higher baseline prevalence of comorbid conditions and Japanese ethnicity seemed to be associated with lower benefit from LVH regression.
CONCLUSIONS: This meta-analysis indicates that regression of echocardiographic LVH in hypertension, even after adjustment for various confounders, is associated with reduction of cardiovascular events. However, future studies are needed to evaluate whether LVH regression is of benefit for all hypertensive patients and ethnic groups.