Abstract 8407: The T-peak to T-end Interval Independently Predicts Both Ventricular Tachyarrhythmia and Death in Patients with Cardiomyopathy and an Implanted Defibrillator

Abstract

Background: The heart rate-corrected T wave peak to T end interval (Tpe c ), an electrocardiographic (ECG) index of dispersion of ventricular repolarization, has been proposed as an indicator for arrhythmic risk. The real-world clinical value of Tpe c for risk stratification is unclear. Methods: We evaluated 327 patients (75% M, LVEF 23±7%) with LVEF <=35% and an ICD. Clinical data and ECGs were analyzed at baseline. Follow up for appropriate ICD therapy and death was conducted via device interrogation and the Social Security Death Index. Results: During device clinic follow-up of 17±12 months, 59 (18%) patients had appropriate ICD therapy, and during mortality follow-up of 30±13 months, 67 (21%) patients died. Tpe c predicted ICD therapy, death, and the combination of appropriate ICD therapy or death (p<0.01 for each endpoint; see Figures stratified by tertiles of Tpe c : T1, T2, T3). On multivariable analysis correcting for other predictors including demographics, clinical data, medication use, and ECG parameters, Tpe c remained predictive of ICD therapy (HR per 10 ms increase: 1.16, p=0.02), all-cause mortality (HR per 10 ms: 1.14, p=0.03), and the combined endpoint of ICD therapy or death (HR per 10 ms: 1.16, p<0.01). Conclusion: In patients with left ventricular systolic dysfunction and an implanted ICD, Tpe c independently predicts both ventricular tachyarrhythmia and overall mortality.