Abstract 2715: Twelve-lead ECG Predicts the Presence and Severity of 3-D Electroanatomic Scars (by Carto) in Patients With Arrhythmias of Right Ventricular Origin
Background: The study was designed to assess whether 12-lead electrocardiogram (ECG) is able to predict the presence/severity of electroanatomic scars (EAS), i.e. low-amplitude areas with bipolar electrogram < 0.5 mV at endocardial voltage mapping, in patients with arrhythmias of right ventricular (RV) origin.
Methods: The study population included 98 patients (67 men and 31 women; mean age 35±3 years) with a left bundle branch block pattern ventricular arrhythmia, who underwent detailed clinical evaluation including ECG and RV endocardial voltage mapping by CARTO system. The extent of EAS was estimated by using an area calculation computer program. Overall extent of EAS was determined as the sum of RV low amplitude areas and expressed as percent RV area, excluding tricuspid and pulmonary valvular annuli. Depolarization and repolarization ECG parameters were correlated with the presence, site and extent of EAS.
Results: Sixty-eight patients (61%) showed ≥1 ECG abnormalities. Low QRS voltages (p < 0.001), epsilon waves (p < 0.008), QRS > 110 ms (p = 0.03) and negative T-wave in V1-V3 (p < 0.001) were significantly associated with the presence of EAS. In the subgroup of 49 patients with EAS, there was a significant trend (p < 0.001) between the extent of T-wave inversion in precordial/inferior leads and the severity of EAS. No T-wave inversion (14 pts) predicted a mean EAS area of 9.52±6.97% (median = 4.85%); T-wave inversion in leads V2-V3 (8 pts) a mean EAS area of 21.61±9.86% (median = 24.00%); T-wave inversion beyond V3 (11 pts) a mean EAS area of 22.89±7.93 (median = 24.90%); and T-wave inversion beyond V3 plus inferior leads (13 pts) a mean EAS area of 29.22±5.67 (median = 30.20%). The correlation remained statistically significant at multivariate analysis (p < 0.001). There was no significant association between any location of T-wave inversion and involvement of specific RV regions, except for T-wave inversion in inferior leads and postero-basal EAS (p = 0.011). There was no association between any ECG depolarization parameters and extent of EAS.
Conclusions: ECG is a useful tool for predicting the presence of RV EAS in patients with arrhythmias of RV origin. ECG repolarization abnormalities but no depolarization changes predict the extent of RV EAS involvement.