Impact of body mass index on left atrial dimension in HOCM patients.

Background Substantial studies have demonstrated that left atrial (LA) enlargement was a robust predictor of atrial fibrillation (AF) and obesity was a modifiable risk factor for cardiovascular diseases. However, the role of body mass index (BMI) on LA dimension in hypertrophic obstructive cardiomyopathy (HOCM) remains unclear. Methods A total of 423 HOCM patients (average BMI 25.4 ± 3.4 kg/m2) were recruited for our study. Participants were stratified into three groups based on BMI: normal weight (BMI < 23 kg/m2), overweight (BMI 23-27.5 kg/m2), and obesity (BMI ≥ 27.5 kg/m2). Results Compared with normal weight, patients with obesity had significantly lower prevalence of syncope (p = 0.007) and moderate or severe mitral regurgitation (p = 0.014), and serum NT-proBNP (p = 0.004). Multiple linear regression analysis indicated that BMI (β = 0.328, p < 0.001), log NT-proBNP (β = 0.308, p < 0.001), presence of AF (β = 0.209, p = 0.001), and left ventricular diastolic diameter index (β = 0.142, p = 0.019) were independently related with LA diameter. However, BMI was not an independent predictor of the presence of AF on multivariable binary logistical regression analysis. Conclusions BMI was independently associated with LA diameter; however, it was not an independent predictor of prevalence of AF. These results suggest that BMI may promote incidence of AF through LA enlargement in HOCM.