Are increased QT, QRS, and JT dispersions associated with ventricular tachycardia in patients late after repair of tetralogy of Fallot?
Increased QT, QRS, and JT dispersions, combined with QRS ≥ 180 ms, are associated with ventricular tachycardia and refine risk stratification late after repair of tetralogy of Fallot.
BACKGROUND: We have previously shown that QRS prolongation (> or = 180 ms) is a risk marker for sustained ventricular tachycardia (VT) late after repair of tetralogy of Fallot (rTOF). We have now examined the dispersion of QT and its components QRS and JT, in an attempt to determine whether any association exists between these measurements and the presence of VT in these patients. METHODS AND RESULTS: QRS duration and QT/QRS/JT dispersion were measured manually from standard ECGs in 10 syncopal rTOF patients (21.4 +/- 4.6 years after repair; group 1) with QRS > or = 180 ms and with documented VT and were compared with 9 rTOF patients with QRS > or = 180 ms and no VT (group 2), 40 rTOF patients with QRS or = 180 ms, refine risk stratification for VT in these patients.
Gatzoulis et al. (Tue,) studied this question.