Authors' Reply

Abstract

minor criteria 1 ; however, exercise plays a major role in right ventricular (RV) physiology and pathophysiology. Authentic ARVD/C gene carriers may demonstrate symptoms and signs that overlap substantially with those in subjects who have other reasons for RV impairment, including strenuous endurance training. 2-5 However, even borderline forms (gene elusive) of ARVD/C carry a potentially poor prognosis, including risk for sudden death. 5,6 Furthermore in patients with ARVD/C, the amount and intensity of exercise have been reported to be associated with decreased RV function and increased ventricular arrhythmias. 7-9 Several studies have shown that the right ventricle is more prone to exercise-induced impairment than the left ventricle in athletes, and such RV alterations have been associated with ventricular arrhythmias. 2,5,10 When performing stress echocardiographic studies, physicians should focus on regional and global RV impairment, especially in patients being evaluated for ventricular arrhythmias or for possible ARVD/C. RV strain using speckle-tracking imaging, RV ejection fraction, and RV annular peak systolic velocity have moderate to good accuracy in discriminating patients with ARVD/C from healthy adults. 11,12 A recent meta-analysis of the echocardiographic assessment of ARVD/C is available. 13 Thus, stress echocardiography may play a role in the initial diagnosis of ARVD/C and for serial evaluation in at-risk first-degree adult relatives of patients with ARVD/C. 14 Will stress or exercise imaging findings be part of future task force criteria? More studies are needed to assess the safety and accuracy of stress echocardiography (multimodal using several or other imaging modalities, including stress cardiac magnetic resonance) for the diagnosis of ARVD/C. 15 ACKNOWLEDGMENT I thank Sarah MacKenzie for English editing.