Epicardial conduction abnormalities in patients with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) and mutation positive healthy family members - A study using electrocardiographic imaging

BackgroundThe diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) in early stages is challenging. The aim of this study was therefore to investigate whether electrocardiographic imaging (ECGI) can detect epicardial conduction changes in ARVC patients and healthy mutation-carriers (M-carriers). MethodTwelve ARVC patients, 20 M-carriers and 8 controls underwent 12-lead ECG, signal-averaged ECG, 2-dimensional echocardiography, 24-hours Holter monitoring and ECGI (body surface mapping and computer tomography with offline analysis of reconstructed epicardial signals). Total and Right Ventricular Activation Time (tVAT and RVAT respectively), area of Ventricular Activation during the terminal 20 milliseconds (aVAte(20)) and the activation patterns were compared between groups. ResultsIn ARVC patients the locations of aVAte(20) were scattered or limited to smaller parts of the right ventricle (RV) versus in controls, in whom aVAte(20) was confined to right ventricular outflow tract (RVOT) and left ventricle (LV) base (+/- RV base). ARVC patients had smaller aVAte(20) (35cm(2) vs 87cm(2), p<0.05), longer tVAT (99msec vs 58msec, p<0.05) and longer RVAT (66msec vs 43msec, p<0.05) versus controls. In 10 M-carriers (50%), the locations of aVAte(20) were also eccentric. This sub-group presented smaller aVAte(20) (53cm(2) vs 87cm(2), p = 0.009), longer RVAT (55msec vs 48msec, p = 0.043), but similar tVAT (65msec vs 60msec, p = 0.529) compared with the M-carriers with normal activation pattern. ConclusionsECGI can detect epicardial conduction abnormalities in ARVC patients. Moreover, the observation of localized delayed RV epicardial conduction in M-carriers suggests an early stage of ARVC and may be a useful diagnostic marker enhancing an early detection of the disease.

Automated summary

This study investigates whether electrocardiographic imaging (ECGI) can detect epicardial conduction changes in early stage arrhythmogenic right ventricular cardiomyopathy (ARVC) patients and healthy mutation-carriers (M-carriers). The results show that ECGI can detect epicardial conduction abnormalities in ARVC patients, and the observation of localized delayed RV epicardial conduction in M-carriers suggests an early stage of ARVC, which could enhance early detection of the disease.