Effect of Surgical Revascularization on QT Dispersion Time in Patients Who Do Not Have Necrotic/Fibrotic Myocardium in Transthoracic Echocardiography

Abstract

Introduction: Prolonged QT dispersion time is known to be associated with cardiac arrhythmias and sudden cardiac death. It was proved previously that electrical heterogenity caused by myocardial ischemia, hypertrophic cardiomyopathy, electrolyte imbalance, heart failure prolongs QT dispersion time. The aim of this study was to investigate the effect of surgical revascularization on QT dispersion time in ischemic patients not having necrotic/fi brotic segments in transthoracic echocardiography. Patients and Methods: Data of patients treated with surgical revascularization due to coronary artery disease are evaluated retrospectively. 247 patients were enrolled into the study after application of exclusion criteria. Patients' electrocardiographic records were evaluated and values of preoperative (QTcd0), postoperative fi rst (QTcd1), postoperative third (QTcd3) and postoperative seventh (QTcd7) day corrected QT dispersion time calculated and compared with each other. Results: There were statistically signifi cant differences between QTcd0 (83.6 ± 2.2) and QTcd1 (55.3 ± 1.7), QTcd3 (50.4 ± 1.2) and QTcd7 (45.3 ± 1.1) (p< 0.001, p< 0.001, p< 0.001 respectively). There was also statistically signifi cant difference between QTcd1 (55.3 ± 1.7) and QTcd7 (45.3 ± 1.1) (p< 0.001), and also between QTcd3 (50.4 ± 1.2) and QTcd7 (45.3 ± 1.1) (p< 0.001). There was no signifi cant difference between QTcd1 (55.3 ± 1.7) and QTcd3 (50.4 ± 1.2) (p= 0.078). Conclusion: Surgical revascularization of non-necrotic/non-fi brotic ischemic myocardium causes statistically signifi cant decrease in QT dispersion time from the postoperative fi rst day.