Author + information
- Farnaz Azarbal,
- Maneesh Singh,
- Gherardo Finocchiaro,
- Vy–Van Le,
- Ingela Schnittger,
- Paul Wang,
- Jonathan Myers,
- Marco Perez and
- Euan Ashley
Atrial fibrillation (AF) is the most common arrhythmia among patients with hypertrophic cardiomyopathy (HCM). The relationship between AF and exercise capacity in this population is incompletely understood. We analyzed the association between AF and exercise capacity in a large HCM cohort.
Patients with HCM underwent symptom–limited cardiopulmonary testing (CPX) at Stanford Hospital between October 2006–October 2012. Baseline demographics, medical history, and resting echocardiograms were obtained for all subjects. Diagnosis of AF was established by review of medical records and baseline electrocardiograms. Those with paroxysmal AF were in sinus rhythm at the time of CPX. Exercise intolerance was defined as peak VO2 <20mL/kg/min. We used multivariate logistic regression to evaluate the association between exercise intolerance and AF.
Among the 265 patients recruited, 55 had AF (28 paroxysmal and 27 permanent). Compared to those without a history of AF, subjects with paroxysmal AF were more likely to have hyperlipidemia, use antiarrhythmic and anticoagulant medications, and have larger left atrial diameter. Paroxysmal AF patients achieved lower peak VO2 (21.9 ±1.7 vs. 26.9 ±10.8, p=0.02) and had more exercise intolerance (60.7%, vs. 27.6%, p<0.001) compared to those without AF. After multivariate adjustment for age, sex, and BMI, exercise intolerance remained significantly associated with paroxysmal AF (OR 4.65, p=0.001). Exercise intolerance was also associated with all AF (OR 3.59, p<0.001), though this was largely driven by the association in the paroxysmal subgroup.
Paroxysmal AF is associated with exercise intolerance in patients with HCM despite being in sinus rhythm at the time of CPX. Paroxysmal AF may serve as a marker of functionally advanced HCM disease. HCM patients with exercise intolerance may benefit from increased screening for occult AF.
Poster Sessions, Expo North
Sunday, March 10, 2013, 9:45 a.m.–10:30 a.m.
Session Title: Sports and Exercise Cardiology: Exercise Tolerance in HCM
Abstract Category: 4. Arrhythmias: AF/SVT
Presentation Number: 1217–258
- 2013 American College of Cardiology Foundation