Abstract 12355: Role of Exercise Stress Testing in Arrhythmogenic Right Ventricular Dysplasia
Introduction: Exercise treadmill testing (ETT) is routinely used in ARVD evaluation, however, the diagnostic and prognostic utility of ETT in ARVD and the safety of exercise stress test is largely unknown.
Methods and Results: The study population included 71 patients who had ETT as a part of their evaluation for ARVD. All subjects had LBBB morphology ventricular arrhythmia. ARVD diagnosis was based on revised task force criteria. ETT was performed using Bruce protocol. All patients with ARVD received implantable defibrillators. Patients were followed on a yearly basis for arrhythmias and for symptoms of heart failure. Findings on ETT were correlated to the final diagnosis and the prognosis during follow up. Of the 71 patients, 29 (41%) were diagnosed with ARVD and the rest had idiopathic ventricular tachycardia (IVT). Mean age was similar between the two groups (ARVD vs. IVT, 41.9 ± 13.3 yrs vs. 40.5 ± 15.2 yrs p=NS). None of the patients had sustained VT during the study. Mean exercise time (11.55±0.36 min vs. 11.55±0.16 min, p=0.99), number of METS (13.3±3 vs. 12.9 ± 3, p=0.56) and the total number of PVC's (6±9 vs 12 ± 22, p =0.19) were similar between the ARVD and the IVT patients. Patients with ARVD were more likely to have LBBB superior axis PVCs (27.5% vs. 7%, P=0.04) and RBBB morphology PVCs (42 vs. 18%, p=0.04) compared to with IVT. Over a mean follow up of 52 ± 24 months, 4 ARVD patients developed heart failure with 1 patient receiving a heart transplant. Among ARVD patients, an exercise capacity of <10 METS (p=0.001) significantly predicted development of heart failure during follow up, whereas RVEF (p=0.11) did not.
Conclusions: Exercise treadmill testing is safe in ARVD and sustained VT during ETT is not common. ETT plays a limited role in diagnosis and does not differentiate from IVT. Frequent LBBB superior axis PVC's favor ARVD diagnosis. Decreased exercise capacity in ARVD predicts future development of symptomatic heart failure.
- © 2010 by American Heart Association, Inc.