Left ventricular structure and systolic function in African Americans: the Atherosclerosis Risk in Communities (ARIC) study

Abstract

Objectives: To estimate prevalence of left ventricular (LV) hypertrophy and its relation to systolic function in a population-based sample of African Americans.

Design: A baseline 2D guided M-mode echocardiogram was conducted as part of a longitudinal cohort study to assess prevalence and cross-sectional relationships between echocardiographic and clinical parameters.

Setting: Data were collected as part of the Atherosclerosis Risk in Communities study.

Participants: Analysis is limited to 1543 African Americans, aged 51-70 years, without clinically apparent cardiovascular or echocardiographically determined valvular disease.

Main outcome measures: LV hypertrophy prevalence was defined as LV mass/ height2.7 > or = 51 g/m2.7. LV systolic chamber function was assessed at the midwall using the ratio of observed midwall fractional shortening (MWS%) to the value predicted from circumferential end-systolic stress.

Results: The prevalence of LV hypertrophy was 33% in men, 38% in women. The prevalence of concentric hypertrophy (LV hypertrophy with relative wall thickness > or = 0.45) was greater than that of eccentric hypertrophy (men: 24% vs 9%; women: 27% vs 11% women). Observed/predicted (O/P) MWS% was strongly and inversely related to LV mass/ height2.7 (P<.001) and LV hypertrophy (P<.001). The O/P MWS% was inversely related to LV mass/height2.7 quartile: O/P MWS% was 106% and 99% in the first and 97% and 89% in the fourth quartile of LV mass/height2.7 for men and women, respectively. Adjusting for age, adiposity, diabetes, blood pressure, antihypertensive medication use, and smoking did not remove association between O/P MWS% and LV mass/height2.7.

Conclusions: LV hypertrophy was highly prevalent in this population-based middle-aged sample of African Americans and was associated with poorer LV systolic chamber function.