Risk Stratification of Ventricular Fibrillation by Two-Dimensional Functional Image of Repolarization Dispersion and T-Wave Alternance Using Synthesized 187-Channel ECG

We developed synthesized 187 channel high-resolution ECG (187ch DREAM-ECG) that can evaluate simultaneously two-dimensional functional images of late potential (LP), RTpeak-end and T-wave current alternance (TWCA) using Mason-Likar lead system. We evaluated the significance of a risk stratification for ventricular fibrillation (VF). The subjects consisted of 20 healthy subject (CONT) and 10 patients with VF (1 idiopathic VF (IVF), 5 long QT syndrome, 2 Brugada syndrome, 1 sarcoidosis and 1 myocardial infarction). We recorded 10 min of 187ch DREAM-ECG. Two-dimensional functional images of recovery time (RTpeak-end; RTp-e) dispersion and LP were obtained by the signal-averaged 187ch VP-ECG. The TWCA value was determined from the relative changes in the averaged current density in the T-wave zone (Tpeak±50 ms) for two T-wave types. In the IVF and LQT with VF case, values of RTpeak-end dispersion and TWCA were higher than those in CONT (RTp-e dispersion; 63±12 ms vs. 26±16 ms, TWCA; 6.5±7.3% vs. 0.5±0.2%). For the Brugada syndrome with VF, positive LP and increased RTc dispersion was demonstrated. For the MI and sarcoidosis with VF, positive LP and increased RTp-e dispersion were associated. We conclude that a novel algorithm using 187ch DREAM-ECG might provide new insights on a risk stratification of VF.