Graft Patency Rate and Risk Factors for Graft Failure among Symptomatic Post Coronary Artery Bypass Graft Surgery Patients

Abstract

BACKGROUND Malaysia, a multiracial country, has been burdened by ischemic heart disease, the leading cause of death for the past 10 years. The success of coronary artery bypass grafting surgery (CABG) particularly depends on the continued patency of aortocoronary grafts. The study aims to identify the graft patency rate and risk factors of graft failure among symptomatic post CABG patients. METHODS Data were collected from 80 patients with a history of CABG, who underwent conventional coronary angiography for refractory angina in Hospital Sultanah Aminah Johor, Malaysia from January 2014 till December 2018. The graft patency was evaluated with conventional coronary angiography. Graft patency was assessed with the Kaplan-Meier method. Differences between graft patency were tested with log-rank test at a 5% significance level and result with p-value <0.05 was considered statistically significant. RESULTS Among the 80 post CABG patients with cardiac symptoms, there were 2 patients with acute myocardial infarction (2.5%) and 24 patients with NSTEMI (30%). 22 patients (27.5%) were found to have all grafts patent despite being persistently symptomatic. Left internal mammary arterial (LIMA) graft remained as the best conduit with a significantly better short, medium, and long term patency (up to 20 years) compared to SVG graft (Log-rank test, p-value < 0.05). Indian race and age less than 70 years had higher risk of SVG graft stenosis. CONCLUSION Type of conduits remains the most important factor in determining the coronary artery bypass graft patency, with LIMA produces the best patency rate in both short and long term.