The relationship between diastolic function of the left ventricle and QT dispersion in patients with myocardial infarction

Lack of synchronicity concerns not only the electrical but also the mechani cal function of the left ventricle and causes impaired ventricular filling. To our knowledge a direct association between electrical dispersion and im pairment of left ventricular filling has not been reported. The study group comprised 71 patients with myocardial infarction. Echocardiographic Dopple r studies and QT dispersion measurements from standard 12-lead electrocardi ograms were performed during the second week of hospitalization. The study population was divided into high, intermediate and low QT dispersion groups . Differences in the left ventricular filling parameters between high and l ow QT dispersion groups were assessed. Patients with high QT dispersion had larger end-diastolic volume (134 +/- 31 vs. 107 +/- 19 ml; P = 0.049) and tended to have shorter E-wave deceleration time (155 +/- 18 vs. 175 +/- 20 ms; P = 0.056) compared with patients with low QT dispersion. There was a n egative correlation between E-wave deceleration time and QT dispersion (r = -0.248; P = 0.05). We conclude that greater dispersion of repolarization i s accompanied by changes in the left ventricular diastolic geometry and mor e 'restrictive' filling. The hypothesis that left ventricular filling abnor malities are caused by increased electrical dispersion deserves further stu dy, especially under controlled, experimental conditions. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.