Dynamic electrocardiographic changes in patients with arrhythmogenic right ventricular cardiomyopathy

Background and objectives Electrocardiographic (ECG) abnormalities of depolarisation and repolarisation contribute to the diagnostic criteria for arrhythmogenic right ventricular cardiomyopathy (ARVC). The development of diagnostic ECG features were investigated in a genotyped cohort with ARVC to provide more sensitive markers of early disease. Methods T-wave inversion (TWI) in right precordial leads, epsilon waves, localised QRS prolongation greater than 110 ms in V1-V3 and QRS dispersion greater than 40 ms were analysed from 317 ECG from 68 genotyped patients (34 with disease-causing mutations) during follow-up of 34628 months. Results 16 patients (23%) had changes during followup, with the appearance of new ECG abnormalities in seven (10%) and dynamic changes in nine (13%). Four developed new and persistent TWI and eight had dynamic TWI in right precordial leads. Three developed new and another three had dynamic epsilon waves. No changes were observed in 10 with and 58 patients without localised QRS prolongation and in six patients with and 61 without QRS dispersion greater than 40 ms. An additional patient with QRS dispersion at baseline had normal depolarisation dispersion during follow-up. None of the nine ARVC patients with dynamic ECG changes had major structural or functional right ventricular abnormalities, suggesting an early stage of the disease. Conclusions New or dynamic ECG changes were observed in 23%. This underscores the importance of serial ECG in the diagnosis of individuals at risk of ARVC, in whom potentially lethal arrhythmia may develop before major abnormalities are detectable with conventional imaging.