QT DISPERSION AND ARRHYTHMIC EVENTS IN IDIOPATHIC DILATED CARDIOMYOPATHY

QT dispersion was measured in the 12-lead standard electrocardiogram i n 107 patients with idiopathic dilated cardiomyopathy (IDC) and 100 ag e- and sex-matched controls without structural heart disease. All 107 study patients with IDC were prospectively followed in order to determ ine possible associations between QT dispersion and arrhythmic events, i.e., sustained ventricular tachycardia, ventricular fibrillation, or sudden death. QT dispersion, rate-corrected QT dispersion, and adjust ed QTc dispersion, which fakes account of the number of leads measured , were significantly greater in patients with IDC than in controls, Du ring 13 +/- 7 months follow-up, arrhythmic events occurred in 12 of 10 7 study patients with IDC (11%). QT dispersion was increased in patien ts with versus without arrhythmic events during follow-up (76 +/- 17 v s 68 +/- 26 ms; p=0.03). QTc dispersion and adjusted QTc dispersion we re not significantly different between patients with and without arrhy thmic events (80 +/- 21 vs 75 +/- 35 ms, and 27 +/- 6 vs 24 +/- 10 ms, respectively), Thus, although QT dispersion was increased in patients with IDC and arrhythmic events during follow-up, its usefulness For a rrhythmia risk prediction was limited by the large overlap of QT dispe rsion between patients with and without crrhythmic events.