Abstract Background Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy that can lead to sudden cardiac death. The diagnostic criterion has recently been revised and through the use of cardiac magnetic resonance (CMR) imaging this study aimed to assess the clinical impact of comparing the original 1994 task force (TF) criterion to the revised 2010 criterion. Methods We evaluated 173 consecutive CMR scans of patients referred with clinical suspicion of ARVC between 2008 and 2011. We then compared the prevalence of major and minor CMR criteria by applying the two criteria. Results Using the 1994 TF criterion, 13 (7.5%) patients had definite, 11 (6.4%) had borderline, and 39 (22.5%) had possible ARVC. Using the 2010 TF criterion, 10 (5.8%) patients had definite, 1 had borderline, and 7 had (0.04%) possible ARVC. With the 1994 criterion, 81 patients satisfied CMR criterion, of which 36 (44%) had major and 45 (56%) had minor criteria. Upon reclassification with the revised criterion, 61 of the 81 patients were not assigned any criteria, even though many patients had significant risk factors. The negative predictive values (NPV) for both CMR criteria were 100% but the positive predictive values (PPV) for combined CMR major or minor criteria improved from 23% to 55%. Conclusions Revision of the criterion has enhanced the diagnostic capabilities of CMR but has resulted in a large cohort of patients not classified. In these patients, there is presently no official consensus on imaging or clinical strategy for surveillance of the evolution of pathology over time.