DISPERSION OF VENTRICULAR REPOLARIZATION IN HYPERTROPHIC CARDIOMYOPATHY

On an averaged QRS-T cycle from a 15-lead record (12-lead electrocardi ogram + XYZ leads) and through interactive editing, four electrocardio graphic indices of the dispersion of ventricular repolarization (DVR) are automatically computed and represent the maximal interlead differe nce of QT and JTend and QT and JTapex. The values of these indices wer e then examined in three clinical groups matched for age and sex: norm al subjects (control), patients with left ventricular hypertrophy (LVH group), and patients with hypertrophic cardiomyopathy (HCM group) wit hout ventricular arrhythmias and without interacting drugs. The mean v alues of all four DVR indices were significantly increased in the HCM group compared with the control group and the LVH group of another ori gin (ie, for the QTe dispersion index, the mean values and the 97.5th percentiles were, respectively, 65 +/- 18 ms and 97 ms in the HCM grou p, 41 +/- 25 ms and 79 ms in the LVH group, and 31 +/- 15 ms and 58 ms in the control group). The maximal QT interval was also significantly longer in the HCM group (464 +/- 30 ms) than in the LVH group (436 +/ - 32 ms) and the control group (428 +/- 25 ms).