Interlead difference between T-peak to T-end intervals in resynchronization patients with an implantable cardioverter-defibrillator

BackgroundThe effectiveness of cardiac resynchronization therapy (CRT) in preventing sudden cardiac death is controversial. Epicardial left ventricular pacing reverses the direction of activation of the left ventricular wall from the epicardium to the endocardium. We evaluated whether the interlead difference between T-peak to T-end (Tp-e) intervals determined by a 187-channel repolarization interval-difference mapping electrocardiograph (187-ch RIDM-ECG) is related to the occurrence of ventricular tachyarrhythmia requiring implantable cardioverter-defibrillator (ICD) therapy in heart failure patients receiving CRT with a defibrillator (CRT-D).Methods and ResultsRepolarization interval-difference mapping electrocardiograph (187-channel) was performed on 61 patients who received CRT-D. Twenty-one patients experienced appropriate ICD therapy. The interlead difference between corrected recovery time intervals was not significantly different between patients with and without appropriate ICD therapy (98 ± 24 milliseconds versus 88 ± 24 milliseconds). The interlead difference between corrected Tp-e intervals was significantly higher in patients with appropriate ICD therapy than in those without (88 ± 22 milliseconds versus 59 ± 23 milliseconds, P < .001).ConclusionThe interlead difference between corrected Tp-e intervals determined by 187-ch RIDM-ECG may be related to appropriate ICD therapy in heart failure patients receiving CRT-D.