T-wave integral: an electrocardiographic marker discriminating patients with arrhythmogenic right ventricular cardiomyopathy from patients with right ventricular outflow tract tachycardia.

Clinical and electrocardiographic (ECG) presentation of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and idiopathic right ventricular outflow-tract tachycardia (RVOT) may be similar. The aim of the study was to assess the validity and utility of T-wave integral measurement as an ECG discriminator of patients with ARVC and RVOT using a body surface mapping (BSM). A 120-channel BSM with quantitative signal analysis of the T-wave integral was performed in 10 patients with ARVC. Results were compared with those obtained from 13 patients with RVOT and a control group of 12 healthy subjects (controls). Age, body mass index, and QRS-axis on surface ECG were not significantly different between the groups. Arrhythmogenic right ventricular cardiomyopathy patients showed a significantly negative T-wave integral in the right lower anterior region of the torso when compared with RVOT (P 0.001). There was no statistically significant difference between RVOT patients and controls. At a cut-off level of 0.3 mV ms, sensitivity and specificity were 83 [area under curve (AUC) 0.85 0.04 for the comparison of ARVC and RVOT]. These differences were pronounced in ARVC patients with a plakophlin-2 mutation (P 0.001). Quantitative analysis of the BSM T-wave integral in distinct anatomical regions discriminates ARVC patients from RVOT patients and controls and may serve as an additional diagnostic tool.