QT-interval prolongation in right precordial leads: an additional electrocardiographic hallmark of Brugada syndrome

J Am Coll Cardiol. 2003 Nov 5;42(9):1632-7. doi: 10.1016/j.jacc.2003.07.005.


Objectives: The aim of this study was to evaluate whether the occurrence of the Brugada Syndrome typical electrocardiogram (ECG) pattern (i.e., right bundle branch block, coved-type ST-segment elevation, and T-wave inversion in the right precordial leads) is characterized by a concomitant lengthening of QT intervals in the right precordial leads.

Background: It has been suggested that the typical ECG pattern of Brugada syndrome is due to a decreased net inward current during phase 1 of the action potential, which also leads to its prolongation in the right epicardium.

Methods: Thirty-two subjects (19 males) age 37 +/- 15 years with a suspicious baseline ECG, or who were relatives of Brugada syndrome patients, underwent 12-lead ECG before and after the administration of flecainide.

Results: The flecainide test was negative in 14 and positive in 18 subjects. After flecainide administration, the positive ECGs were characterized by a greater QT interval corrected for heart rate (QTc) prolongation in the right precordial leads than that in the negative ECGs (78.2 +/- 35.5 ms vs. 22.0 +/- 28.4 ms in V(1) and 107.1 +/- 43.8 ms vs. 26.7 +/- 30.1 ms in V(2); p < 0.01), whereas there was no difference in the QTc prolongation in the left precordial leads (55.2 +/- 25.3 ms vs. 35.1 +/- 28.1 ms in V(5) and 53.1 +/- 32.8 ms vs. 27.3 +/- 22.4 ms in V(6); p = NS).

Conclusions: In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads.

MeSH terms

  • Adult
  • Anti-Arrhythmia Agents
  • Bundle-Branch Block / diagnosis*
  • Bundle-Branch Block / genetics
  • Bundle-Branch Block / physiopathology
  • Electrocardiography*
  • Female
  • Flecainide
  • Heart Conduction System / physiopathology*
  • Humans
  • Male
  • Middle Aged
  • Polymorphism, Single-Stranded Conformational
  • ROC Curve
  • Sensitivity and Specificity


  • Anti-Arrhythmia Agents
  • Flecainide