Tpeak-Tend interval and Tpeak-Tend/QT ratio as markers of ventricular tachycardia inducibility in subjects with Brugada ECG phenotype.
OBJECTIVE
The present study investigated whether several ECG markers of ventricular repolarization are associated with ventricular tachycardia/fibrillation (VT/VF) inducibility in subjects with type 1 ECG pattern of Brugada syndrome (BS).


RESULTS
The clinical data of 23 individuals (19 males, age 42.69 +/- 14.63) with spontaneous (n = 10) or drug-induced (n = 13) type 1 ECG pattern of BS who underwent programmed ventricular stimulation were analysed. Sustained VT/VF was induced in 17 subjects (74%) and was significantly associated with the presence of spontaneous type 1 ECG of BS (P = 0.012). Among the studied ECG repolarization markers, subjects with inducible VT/VF displayed an increased T(peak)-T(end) interval in leads V(2) (88.82 +/- 15.70 vs. 78.33 +/- 4.08 ms, P = 0.02) and V(6) (76.33 +/- 10.08 vs. 66.66 +/- 5.16 ms, P = 0.04) and a greater T(peak)-T(end)/QT ratio in lead V(6) (0.214 +/- 0.028 vs. 0.180 +/- 0.014, P = 0.009) compared with those without arrhythmias. Ventricular tachycardia/fibrillation inducibility was not associated with arrhythmic events during a mean follow-up period of 4.61 +/- 2.14 years (P = 0.739).


CONCLUSIONS
The T(peak)-T(end) interval and T(peak)-T(end)/QT ratio were associated with VT/VF inducibility in BS. The utility of T(peak)-T(end)/QT ratio as a new marker of arrhythmogenesis in BS requires further studies, including a large number of patients.
Letsas
Konstantinos P
KP
Abteilung Rhythmologie, Herz-Zentrum, Südring 15, 79189 Bad Krozingen, Germany. k.letsas@mail.gr
Weber
Reinhold
R
Astheimer
Klaus
K
Kalusche
Dietrich
D
Arentz
Thomas
T
D000328:Adult; D000404:Ajmaline / Q000009:adverse effects; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects; D015415:Biomarkers; D053840:Brugada Syndrome / Q000139:chemically induced / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D005424:Flecainide / Q000009:adverse effects; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000453:epidemiology* / Q000503:physiopathology*; D014693:Ventricular Fibrillation / Q000453:epidemiology / Q000503:physiopathology
D000889:Anti-Arrhythmia Agents; D015415:Biomarkers; D000404:Ajmaline; D005424:Flecainide