The impacts of percutaneous coronary intervention to treat chronic total occlusion of right coronary artery on the 5-year prognosis: A single-centered retrospective study

Background: Chronic total occlusions (CTO) occur in about 20% of patients referred for coronary angiography, and right coronary artery (RCA) CTO has been reported in 38-50% of the entire CTO population. Limited data on angiographic and procedural characteristics of RCA-CTO and the risk of adverse cardiac events asks for a detailed study.

Methods: From 2010 to 2013, patients with attempted revascularization of at least one CTO lesion were included and followed up to 5 years after PCI. Eligible patients are assigned to RCA-CTO and non-RCA-CTO groups based on their target vessels. The primary endpoint was major adverse cardiovascular events (MACEs; a composite of all-cause death, myocardial infarction (MI) or rehospitalization for heart failure), and secondary endpoints were cardiac death, target lesion revascularization (TLR) and target vessel revascularization (TVR).

Results: The present study included 2659 eligible patients, among which 1285 patients were assigned to the RCA-CTO group, whereas 1374 patients were assigned to the non-RCA-CTO group. Lesions in RCA had longer lesion length, higher J-CTO score, higher rates of severe vessel tortuosity, a higher percentage of Rentrop grade 2-3, and more likely to be re-try lesion than those in LAD or LCX (all P < 0.01). CTO lesions in RCA reached less successful recanalization and post-procedural TIMI 3 flow (all <0.01). Multivariate Cox analysis revealed that RCA-CTO was not associated with primary outcome MACEs. Besides MACEs, RCA-CTO was also not associated with cardiac death, but was significantly associated with TLR and TVR (adjusted HR: 1.37 [95% CI:1.07-1.76], P = 0.01; adjusted HR: 1.43 [95% CI:1.13-1.82], P = 0.003).

Conclusion: RCA-CTO lesions, which had more complex angiographic features, independently contributed to TLR and TVR but not to MACEs or cardiac death in the 5 years of follow-up.