Percutaneous coronary intervention due to chronic total occlusion in the left main coronary artery after bypass grafting: A feasible option in selected cases

Abstract

Introduction: Chronic total occlusion (CTO) of the left main coronary artery (LMCA) is an infrequent finding. Revascularization is recommended in the presence of demonstrated viability or ischemia. Coronary artery bypass grafting (CABG) has long been considered the preferred option. Patients with previous CABG due to LMCA disease with occlusion of one graft and progression of the LMCA to CTO constitute a special population, as just one ischemic artery remains. For these patients, there is no other option for revascularization other than cardiac surgery (requiring resternotomy) or percutaneous coronary intervention (PCI) of the LMCA.

Methods and results: Out of 620 patients with CTO diagnosed in our center, we identified five with previous CABG due to LMCA disease for a retrospective case series. They had occlusion of one graft and progression of the LMCA to CTO. All five underwent PCI. Each patient received a functional classification for angina, myocardial ischemic tests, and a follow-up coronary angiogram during a median follow-up of 63 months. Coronary angiogram showed CTO of the semi-protected LMCA lesions with two CABGs previously performed in all patients, one occluded and the other patent. Three patients had occluded saphenous vein grafts to the circumflex coronary artery, and the rest had left internal mammary artery-left anterior descending artery CABG failure. Ischemia and viability were demonstrated. Surgery was ruled out due to high surgical risk. PCI due to CTO of the LMCA with drug-eluting stents was performed. In a five-year follow-up period, four patients remained asymptomatic and event free. One post-PCI death occurred from non-cardiovascular cause.

Conclusions: PCI due to CTO of the LMCA following CABG can be successful and safe and can provide sustained clinical improvements in selected cases.

Keywords: Chronic total occlusion; Cirurgia coronária; Coronary artery bypass grafting; Left main coronary artery; Oclusão crónica total; Tronco comum coronário.