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/m(2)) were recruited for our study. Participants were stratified into three groups based on BMI: normal weight (BMI < 23 kg/m(2)), overweight (BMI 23–27.5 kg/m(2)), and obesity (BMI ≥ 27.5 kg/m(2)). 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.