Although contributors to remodeling of the left ventricle (LV) have been well studied in general population cohorts, few data are available describing factors influencing changes in left atrial (LA) structure.
METHODS AND RESULTS:
Maximum LA volume was determined by cardiac magnetic resonance imaging among 748 participants in the Dallas Heart Study at 2 visits a mean of 8 years apart. Associations of changes in LA volume (?LAV) with traditional risk factors, biomarkers, LV geometry, and remodeling by cardiac magnetic resonance imaging and detailed measurements of global and regional adiposity (by magnetic resonance imaging and dual-energy x ray absorptiometry) were assessed using multivariable linear regression. Greater ?LAV was independently associated with black and Hispanic race/ethnicity, change in systolic blood pressure, LV mass and ?LV mass, N-terminal probrain natriuretic peptide and change in N-terminal probrain natriuretic peptide, and body mass index (P<0.05 for each). In subanalyses, the associations of ?LAV with LV mass parameters were driven by associations with baseline and ?LV end diastolic volume (P<0.0001 for each) and not wall thickness (P=0.21). Associations of ?LAV with body mass index were explained exclusively by associations with visceral fat mass (P=0.002), with no association seen between ?LAV and subcutaneous abdominal fat (P=0.47) or lower body fat (P=0.30).
Left atrial dilatation in the population is more common in black and Hispanic than in white individuals and is associated with parallel changes in the LV. LA dilatation may be mediated by blood pressure control and the development of visceral adiposity.