The utility of the 1994 versus the revised 2010 arrhythmogenic right ventricular cardiomyopathy (ARVC) task force diagnostic criteria for identifying mutation-positive probands with ARVC

Background Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiac disorder characterised by structural and functional abnormalities of the right ventricle with or without left ventricular involvement. In 1994, Task Force criteria (TFC) were proposed for the diagnosis of ARVC and were found to be highly specific but lacked sensitivity. In 2010, revised TFC were proposed to increase sensitivity and facilitate diagnosis in those with subtle phenotypes. Purpose To compare the utility of the 1994 vs the 2010 TFC for the diagnosis of mutation-positive probands with ARVC in the IMHOTEP (The African Cardiomyopathy and Myocarditis Registry Program) study. Method 162 participants with the suspicion of ARVC were referred between May 2003 and May 2018. After the exclusion of 12 participants lacking sufficient clinical data, 150 cases were reviewed and classified using both 1994 and 2010 TFC by a diagnostic panel in an hospital. Results 82 participants were found to have an alternative diagnosis or insufficient criteria and were excluded. 68 participants were diagnosed with ARVC by the diagnostic panel and included; 14/68 participants with ARVC were found to be mutation-positive. Mutation-positive probands presented at a significantly younger age compared to the mutation-negative group (29±14 years vs 39±13 years, p=0.009), suggesting an earlier onset of ARVC. Common reasons for presentation in the mutation-positive cohort included palpitations (79%) and presyncope (64%), with twice the number of participants presenting with sustained ventricular tachycardia compared to mutation-negative participants (79% vs 47%, p=0.036). The diagnostic yield of the 2010 vs 1994 TFC in participants with ARVC (n=68) revealed more participants with a definite diagnosis (77% vs 69%, p=0.267). A 67% change in diagnosis from 1994 borderline to 2010 definite was observed. Mutation-positive participants had a higher yield for definite ARVC compared to mutation-negative participants (100% vs 86%). When comparing the mean number of task force (TF) major and minor criteria according to mutation status, we found a significant difference in the mean number of 2010 TF major criteria between mutation-positive and mutation-negative groups, even with the exclusion of gene mutation as a criterion (2.50±0.86 vs 1.74±0.85, p=0.005). We assessed each diagnostic modality's contribution to the 2010 TF major criteria in mutation-positive definite participants and found cardiac magnetic resonance contribution statistically significant, p=0.021. Conclusion Mutation-positive ARVC probands were found to be younger, more likely to present with sustained VT, and fulfilled a significantly higher number of 2010 TF major criteria than mutation-negative probands. The evolution in classification between the 2010 and 1994 TFC suggests that reclassifying participants recruited in traditional ARVC registries according to updated criteria is worthwhile. Funding Acknowledgement Type of funding source: None