Optimal method of measuring the T-peak to T-end interval for risk stratification in primary prevention.
Several published investigations demonstrated that a longer T-peak to T-end interval (Tpe) implies increased risk for ventricular tachyarrhythmia (VT/VF) and mortality. Tpe has been measured using diverse methods. We aimed to determine the optimal Tpe measurement method for screening purposes.



We evaluated 305 patients with LVEF ≤ 35% and an implantable cardioverter-defibrillator implanted for primary prevention. Tpe was measured using seven different methods described in the literature, including six manual methods and the automated algorithm '12SL', and was corrected for heart rate. Endpoints were VT/VF and death. To account for differences in the magnitude of Tpe measurements, results are expressed in standard deviation (SD) increments. We evaluated the clinical utility of each measurement method based on predictive ability, fraction of immeasurable tracings, and intra- and interobserver correlation. >Over 31 ± 23 months, 82 (27%) patients had VT/VF, and over 49 ± 21 months, 91 (30%) died. Several rate-corrected Tpe measurement methods predicted VT/VF (HR per SD 1.20-1.34; all P < 0.05), and nearly all methods (both corrected and uncorrected) predicted death (HR per SD 1.19-1.35; all P < 0.05). Optimal predictive ability, readability, and correlation were found in the automated 12SL method and the manual tangent method in lead V2.



For the prediction of VT/VF, the utility of Tpe depends upon the measurement method, but for the prediction of mortality, most published Tpe measurement methods are similarly predictive. Heart rate correction improves predictive ability. The automated 12SL method performs as well as any manual measurement, and among manual methods, lead V2 is most useful.
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Todd M
TM
Rosenthal
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Daniel
D
Masvidal
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Freddy M
FM
Abi Samra
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Michael L
ML
Bernard
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Sammy
S
Khatib
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Glenn M
GM
Polin
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Paul A
PA
Rogers
GE Healthcare, 9900 W. Innovation Drive, Wauwatosa, WI 53226, USA.
Joel Q
JQ
Xue
Department of Cardiology, Ochsner Medical Center, 1514 Jefferson Highway, New Orleans, LA 70121, USA.|Ochsner Clinical School, University of Queensland School of Medicine, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
Daniel P
DP
Morin
D000200:Action Potentials; D000368:Aged; D000369:Aged, 80 and over; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000295:instrumentation; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011322:Primary Prevention / Q000295:instrumentation; D018570:Risk Assessment; D012307:Risk Factors; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D014693:Ventricular Fibrillation / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D016277:Ventricular Function, Left