Electrocardiographic Changes After Percutaneous Coronary Intervention for Chronic Total Occlusion

BACKGROUND: It is unclear if successful percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) can lead to favorable electrophysiologic changes. AIMS: This study seeks to identify whether electrocardiogram (ECG) markers of arrhythmia risk change after successful CTO revascularization. METHODS: Signals from all 10-s 12-lead institutional ECGs were compiled from all patients who underwent CTO PCI between 1/1/2019 and 10/1/2023 at a tertiary medical center. Custom code was developed to analyze ECG signal data and report ECG measurements. ECG changes after PCI were compared for patients with and without technical success, and in patients with a failed attempt followed by a successful one. RESULTS: A total of 1520 CTO PCIs performed in 1233 patients were included, and 89.8% achieved successful revascularization. In the 1452 cases with ECGs available before and < 12 months after CTO PCI, QT dispersion changed by a median [IQR] of 0 [-16 to 14] ms after successful cases and increased by 8 [-12 to 24] ms after unsuccessful cases (p = 0.0456), but no significant differences were observed in any other arrhythmia risk markers. In the 562 cases with ECGs before and 1-12 months after the intervention, no significant differences were observed between patients with successful or unsuccessful CTO PCI. T-wave axis, but not QRS-T angle, showed a different response (p = 0.0307) when a CTO was revascularized during a repeat PCI after an initially unsuccessful attempt, in the subset of 55 applicable patients. CONCLUSIONS: Successful CTO PCI is not associated with durable changes in ECG features linked to arrhythmia risk.