Abstract 4134896: Clinical and Echocardiographic Markers for the Prediction of Incident Atrial Arrhythmias in Hypertrophic Cardiomyopathy

Introduction: Hypertrophic cardiomyopathy (HCM), in addition to increasing the risk for heart failure and sudden cardiac death, augments the risk for atrial fibrillation (AF) and atrial flutter (AFL). We aimed to identify clinical and echocardiographic risk factors that are predictive of incident AF/AFL in HCM patients. Methods: This retrospective study included 99 HCM patients from University of Chicago without prior AF/AFL, followed for a median of 3.2 years (IQR: 11.5 months-6.9 years). Clinical data were obtained via chart review; echocardiographic findings were obtained using AI software (Us2.ai) with measurements audited by a level III echocardiography reader. Statistical testing included Chi-square/Fisher’s exact (categorical variables) and T-test/Wilcoxon rank sum (continuous variables). Univariate and multivariate Cox regressions assessed predictive value of risk factors for AF/AFL. Results: 18 HCM patients (18%) developed AF/AFL ( Table 1 ). On univariate analysis, older age (HR 1.06, 95%CI 1.02-1.11, p=0.002), hypertension (HR 8.32, 95%CI 1.10-63.20, p=0.04), diabetes (HR 3.90, 95%CI 1.51-10.03, p=0.005), prior stroke (CVA, HR 3.81, 95%CI 1.34-10.86, p=0.012), and NYHA class II-IV (HR 8.48, 95%CI 2.97-24.21, p<0.001) predicted AF/AFL. E/A (p=0.04), E/e’ (p=0.028), MV-A (p=0.022), and LVEF (p=0.02) were also significant predictors ( Figure 1 ). LVEF (HR 0.92, 95%CI 0.87-0.98, p=0.013) remained a significant predictor of AF/AFL on multivariate analysis controlling for age, hypertension, diabetes, CAD, CVA, and NYHA class. Conclusions: Traditional risk factors including age, hypertension, diabetes, CVA, and NYHA class are significant predictors of incident AF/AFL in HCM patients, highlighting the need for comprehensive risk factor evaluation. Even after adjustment for these clinical markers, LVEF independently predicts new AF/AFL in HCM patients, underscoring the importance of routine echocardiographic assessment for risk stratification in this patient population.