Echocardiographic findings in patients meeting task force criteria for arrhythmogenic right ventricular dysplasia: New insights from the multidisciplinary study of right ventricular dysplasia

OBJECTIVES: The purpose of this study was to quantify the echocardiographic abnormalities in probands who were newly diagnosed with arrhythmogenic right ventricular dysplasia (ARVD). BACKGROUND: The diagnosis of ARVD remains challenging. The Multidisciplinary Study of Right Ventricular Dysplasia was initiated to characterize the cardiac structural, clinical, and genetic aspects of ARVD. METHODS: Detailed echocardiograms were performed in 29 probands and compared with echoes from 29 normal control patients matched for age, gender, body size, and year of echo. Right atrial (RA) and right ventricular (RV) chamber dimensions, RV regional function, and the presence of morphologic abnormalities (hyper-reflective moderator band, trabecular derangement, and sacculations) were assessed. The RV systolic function was calculated as RV fractional area change (FAC). RESULTS: The RV dimensions were significantly increased, and RV FAC was significantly decreased in probands versus control patients (27.2 ± 16 mm vs. 41.0 ± 7.1 mm, p = 0.0003). The right ventricular outflow tract (RVOT) was the most commonly enlarged dimension in ARVD probands (37.9 ± 6.6 mm) versus control patients (26.2 ± 4.9 mm, p < 0.00001). A RVOT long-axis diastolic dimension >30 mm occurred in 89% of probands and 14% of controls. The RV morphologic abnormalities were present in many probands (trabecular derangement in 54%, hyper-reflective moderator band in 34% and sacculations in 17%) but not in controls. CONCLUSIONS: Probands with ARVD have significant RA and RV enlargement and decreased RV function, which can be easily assessed on standard echocardiographic imaging. These parameters should be measured when ARVD is suspected and compared with normal values.