Patient-Reported Atrial Fibrillation After Septal Myectomy for Hypertrophic Cardiomyopathy

Background: Patient-reported outcomes are important metrics of medical and surgical care. In this study, we investigated the prevalence and risk factors of patient-reported postdischarge atrial fibrillation (AF) after septal myectomy for obstructive hypertrophic cardiomyopathy. Methods: Patients undergoing transaortic septal myectomy from August 2001 to January 2017 were contacted regarding postdischarge AF through questionnaire-based surveys sent at 3, 5, and 10 years post procedure. For each patient, the most recent survey response was analyzed. Results: Among 949 patients, 248 (26.1%) last responded at 3 years post procedure, 353 (37.2%) at 5 years, and 348 (36.7%) at 10 years. The overall incidence of patient-reported postdischarge AF was 34.4% (n = 326), and at 3, 5, and 10 years, the incidences were 22.2%, 34.8%, and 42.5% (P < .001). After multivariable adjustment, history of preoperative AF (odds ratio [OR] 5.566, P < .001), early postoperative AF within the first 30 days (OR 2.211, P < .001), preoperative left atrial volume index (OR 1.014, P = .005), postoperative right ventricular systolic pressure (OR 1.021, P = .013), postoperative moderate or greater mitral valve regurgitation (OR 1.893, P = .022), and preoperative septal thickness (OR 1.043, P = .036) were independently associated with patient-reported postdischarge AF. Conclusions: The incidence of patient-reported postdischarge AF increases with increasing length of follow-up after septal myectomy. We identified several risk factors for late postdischarge AF that were associated with chronicity of left ventricular outflow tract obstruction, and earlier intervention may mitigate late atrial arrhythmias.