Effect of a successful percutaneous coronary intervention for chronic total occlusion on parameters of ventricular repolarization

BACKGROUNDCoronary collaterals may be insufficient for restoring blood flow to normal levels in patients with chronic total occlusions (CTO), leading to myocardial ischemia and electrical inhomogeneity in the ventricles. We evaluated the effect of percutaneous CTO revascularization on parameters of ventricular repolarization, including the T wave peak-to-end interval (TpTe) interval, the TpTe/QT ratio, and QT dispersion. PATIENTS AND METHODSA total of 114 patients who underwent CTO percutaneous coronary intervention (PCI) of any major coronary artery were divided into two groupsthe successful CTO PCI group (n=90) and the failed CTO PCI group (n=24). Patients’ 12-lead ECGs were analyzed within 24 h before revascularization and 24–48 h after the procedure for the following parameterscorrected QT interval (QTc) dispersion, TpTe interval (V2 and V5), and TpTe/QT ratio (V2 and V5). Subsequently, the successful CTO PCI group was divided into subgroups according to the Rentrop class, number of diseased vessels, and target vessels for further evaluation. RESULTSThere was no significant difference between the successful and the failed CTO PCI groups in terms of any baseline demographic or angiographic characteristic, or ventricular repolarization parameter. The post-PCI values of TpTe (85.3±12.8 vs. 74.8±10.4; P