ARVD/C Diagnosis: Impact of New Task Force Criteria

Background —Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C) diagnostic Task Force criteria (TFC) proposed in 1994 are highly specific but lack sensitivity. A new international Task Force modified criteria to improve diagnostic yield. Aim: comparison of diagnosis by 1994 TFC versus newly proposed criteria in 3 patient groups. Methods and Results —In new TFC, scoring by major and minor criteria is maintained. Structural abnormalities are quantified and TFC highly specific for ARVD/C upgraded to major. Furthermore, new criteria are added: terminal activation duration of QRS≥55ms, ventricular tachycardia with left bundle branch block morphology and superior axis, and genetic criteria. Three groups were studied: 1) 105 patients with proven ARVD/C according to 1994 TFC, 2) 89 of their family members and 3) 39 patients with probable ARVD/C (i.e. 3 points by 1994 TFC). All were screened for pathogenic mutations in desmosomal genes. Three ARVD/C patients did not meet the new sharpened criteria on structural abnormalities and thereby did not fulfill new TFC. In 62 of 105 proven ARVD/C patients mutations were found, 58 in the gene encoding Plakophilin2 ( PKP2 ), 3 in Desmoglein2, 3 in Desmocollin2 and 1 in Desmoplakin. Three patients had bigenic involvement. Ten additional relatives (11%) fulfilled new TFC: 9 (90%) were females and all carried PKP2 mutations. No relatives lost diagnosis by application of new TFC. Of probable ARVD/C patients, 25 (64%) fulfilled new TFC: 8 (40%) females and 14 (56%) carrying pathogenic mutations. Conclusions —In this first study applying new TFC to patients suspected of ARVD/C, 64% of probable ARVD/C patients and 11% of family members were additionally diagnosed. Especially ECG criteria and pathogenic mutations contributed to new diagnosis. Newly proposed TFC have a major impact in increasing diagnostic yield of ARVD/C.