Abstract 16086: Spectrum of Imaging Findings on Cardiac MR in Subjects with an Arrythmogenic Right Ventricular Cardiomyopathy-Associated Gene Mutation

Abstract

Introduction: Arrythmogenic right ventricular cardiomyopathy (ARVC) is thought to predominantly affect the right ventricle. Our objective was to evaluate the incidence and extent of both right and left ventricular involvement on cardiac magnetic resonance (CMR) imaging in subjects who have an ARVC-associated gene mutation.

Methods: We enrolled 84 subjects (mean age 35+15 years, 48% men) with an ARVC - associated-desmosomal gene mutation. Subjects were divided into two groups: probands (Group A) and family members (Group B). All subjects in group A and 21subjects (39.6%) of group B met major TFC. CMR images were qualitatively assessed for regional wall motion abnormalities, fat infiltration and delayed enhancement. Quantitative analysis of biventricular size and function were also recorded. Incidence of each abnormality was reported in the entire cohort, and compared between the two groups.

Results: Group A had 31 subjects (36.9%) and Group B had 53 subjects (63.1%). In the entire cohort, 43 subjects (51%) had one or more abnormalities on CMR. Of these, 24 (56%) had biventricular involvement and 4 (9%) had isolated LV involvement. In Group A and B, the most common abnormalities were RV regional wall motion abnormalities (74.2%, 20.8%, respectively), typically in the free wall, and LV fat deposition (48.4%, 9.4%). Biventricular involvement was present in 54.8% and 11.3% of subjects in Group A and B, respectively. RV ejection fraction was significantly lower (34% vs. 49%, p=0.007) and RV end-diastolic volume index was significantly higher (109 mL/m² vs. 78 mL/m², p<0.001) in Group A compared with Group B.

Conclusion: CMR frequently detects biventricular abnormalities in subjects with an ARVC-associated gene mutation. Approximately half of the subjects may have one or more abnormality on CMR, and many of the abnormalities are biventricular.