The effect of revascularization of a chronic total coronary occlusion on electrocardiographic variables. A sub-study of the EXPLORE trial

Introduction

Chronic total coronary occlusions (CTOs) have been associated with a higher prevalence of ventricular arrhythmias compared to patients without a CTO. We evaluated the effect of CTO revascularization on electrocardiographic (ECG) variables.

Methods

We studied a selection of ST-elevation myocardial infarction patients with a concomitant CTO enrolled in the EXPLORE trial. ECG variables and cardiac function were analysed at baseline and at 4?months follow-up.

Results

Patients were randomized to percutaneous coronary intervention (PCI) of their CTO (n?=?77) or to no-CTO PCI (n?=?81). At follow-up, median QT dispersion was significantly lower in the CTO PCI group compared to the no-CTO PCI group (46?ms [33–58] vs. 54?ms [37–68], P?=?0.043). No independent association was observed between ECG variables and cardiac function.

Conclusion

Revascularization of a CTO after STEMI significantly shortened QT dispersion at 4?months follow-up. These findings support the hypothesis that CTO revascularization reduces the pro-arrhythmic substrate in CTO patients.