Right-ventricular enlargement in arrhythmogenic right-ventricular cardiomyopathy is associated with decreased QRS amplitudes and T-wave negativity.

Background Arrhythmogenic right-ventricular cardiomyopathy (ARVC) can lead to RV dilatation. We hypothesized that electrocardiographic characteristics including QRS amplitudes in the extremity- and precordial leads, the S amplitude in lead V1, and extent of T-wave negativity over the precordial leads are related to RV dilatation in this condition. Methods In 42 ARVC patients and 42 controls, we correlated total QRS amplitude in the extremity leads (∑QRSext), precordial leads (∑QRSprec) and in all leads (∑QRStot : summation of ∑QRSext and ∑QRSprec), S amplitude in lead V1 and the extent of T-wave inversion in the precordial leads (V1 vs. beyond V1) with RV end diastolic diameter (RVEDD) by echocardiography. Results In the ARVC group, the mean age was 46 ± 14 years, 31 patients were male, 28 had an implantable cardioverter defibrillator (ICD), and 7 had a LV ejection fraction (EF) < 55%. The control group was age- and gender matched to the ARVC cohort. In contrast to controls, the ∑QRSext (regression coefficient (RC), −0.29; P = 0.020), ∑QRSprec (RC, −0.20; P = 0.015), and ∑QRStot (RC, −0.14; P = 0.009) were lower with RV dilatation in ARVC. S amplitude in lead V1 was not related to RV diameter (RC, −0.98; P = 0.088). Precordial T-wave inversion beyond lead V1 (V2-V6) was associated with a larger RV diameter (RC, 8.58; P = 0.012). Conclusions Summed QRS amplitudes in the extremity and precordial leads, and T-wave inversion beyond lead V1 are associated with RV dilatation in patients with ARVC.