Long-term outcomes after revascularization in chronic total and non-total occluded coronary arteries: A regionwide cohort study.

Background: Understanding the prognostic impact of percutaneous coronary intervention (PCI) in chronic total occlusion (CTO) is crucial for patient management. Previous studies have primarily been studying prognostic impact of successful versus unsuccessful CTO PCI. This study investigated the prognostic impact of successful and unsuccessful percutaneous coronary intervention (PCI) of chronic total occluded coronary arteries (CTO) with non-CTO PCI as reference.

Methods: Patients treated with PCI from 2009 to 2019 in the Central Region of Denmark were included in a population-based cohort study. We compared successful and unsuccessful CTO PCI with non-CTO PCI. Exclusion criteria was myocardial infarction within 30 days. Primary outcome was difference in a composite major adverse cardio- and cerebrovascular events (MACCE) encompassing all-cause death, any myocardial infarction, stroke, hospitalization for heart failure or revascularization tracked via nationwide registries.

Results: Of 21,141 screened patients, 10,638 were enrolled: 9,065 underwent non-CTO PCI, 1,300 had successful CTO PCI, and 273 had unsuccessful CTO PCI. Median follow-up time was 5.9 [3.5;9.0] years and 4,750 MACCEs were recorded. Compared to non-CTO PCI, the adjusted MACCE rate for successful CTO PCI was equivalent (Hazard Ratio (HR): 0.98, 95% Confidence Interval (CI): 0.90-1.07, p = 0.71). In contrast, unsuccessful CTO PCI was associated with a higher MACCE rate (HR: 1.22, 95% CI: 1.04-1.43, p<0.01). HR was adjusted for age, body-mass index, previous revascularization, smoking, kidney disease, two or three-vessel disease, left ventricular ejection fraction, diabetes and comorbidities.

Conclusions: The pre-specified hypothesis was accepted. Successful CTO PCI was associated with equivalent long-term outcomes as non-CTO PCI, and unsuccessful CTO PCI was identified as a high-risk group associated to worse outcomes.