TY - JOUR T1 - Exercise capacity and paroxysmal atrial fibrillation in patients with hypertrophic cardiomyopathy JF - Heart JO - Heart SP - 624 LP - 630 DO - 10.1136/heartjnl-2013-304908 VL - 100 IS - 8 AU - Farnaz Azarbal AU - Maneesh Singh AU - Gherardo Finocchiaro AU - Vy-Van Le AU - Ingela Schnittger AU - Paul Wang AU - Jonathan Myers AU - Euan Ashley AU - Marco Perez Y1 - 2014/04/15 UR - http://heart.bmj.com/content/100/8/624.abstract N2 - Background Atrial fibrillation (AF) is the most common arrhythmia among patients with hypertrophic cardiomyopathy (HCM). The relationship between paroxysmal AF and exercise capacity in this population is incompletely understood. Methods Patients with HCM underwent symptom-limited cardiopulmonary testing with expired gas analysis at Stanford Hospital between October 2006 and October 2012. Baseline demographics, medical histories and resting echocardiograms were obtained for all subjects. Diagnosis of AF was established by review of medical records and baseline ECG. Those with paroxysmal AF were in sinus rhythm at the time of cardiopulmonary testing with expired gas analysis. Exercise intolerance was defined as peak VO2<20 mL/kg/min. We used multivariate logistic regression to evaluate the association between exercise intolerance and paroxysmal AF. Results Among the 265 patients recruited, 55 had AF (28 paroxysmal and 27 permanent). Compared with those without AF, subjects with paroxysmal AF were older, more likely to use antiarrhythmic and anticoagulant medications, and had larger left atria. Patients with paroxysmal AF achieved lower peak VO2 (21.9±9.2 mL/kg/min vs 26.9±10.8 mL/kg/min, p=0.02) and were more likely to have exercise intolerance (61% vs 28%, p<0.001) compared with those without AF. After adjustment for age, sex and body mass index (BMI) exercise intolerance remained significantly associated with paroxysmal AF (OR 4.65, 95% CI 1.83 to 11.83, p=0.001). Conclusions Patients with HCM and paroxysmal AF demonstrate exercise intolerance despite being in sinus rhythm at the time of exercise testing. ER -