Left Internal Mammary Artery Versus Reversed Saphenous Vein Graft as Conduit to Left Anterior Descending Artery in South Indian Patients with Coronary Artery Disease Undergoing Coronary Artery Bypass Surgery

Introduction: Coronary artery disease is the most common adult disease, and the most common cause for stable/unstable angina, acute myocardial infarction, ischemic cardiomyopathy with congestive heart failure, and sudden cardiac death. Coronary artery bypass grafting (CABG) remains the most durable revascularization procedure for coronary artery disease. Materials and Methods: A total of 40 patients of South Indian origin, with uncomplicated coronary artery disease with good LV function (left ventricular ejection fraction [LVEF] (%) 47.77 [4.94]), who were divided into two equal and comparable groups, underwent elective classical CABG in 2009. Group I had left internal mammary artery (LIMA) grafted to left anterior descending (LAD), whereas reversed saphenous vein graft (rSVG) was used in Group II. LAD diameter was 1.486 (0.19) mm. All were ventilated, with minimal inotropic support, when indicated and discharged by 7-10 days. Cardiac enzymes (troponin-T and CKMB) were analyzed 6 and 12 h after surgery and on discharge. In pre- and post-operative angina class, LVEF was assessed by clinical assessment and 2D echocardiography. Follow-up was done clinically by 2D echocardiography at 1 and 3 months. Results: There were 2 mortalities in each group, due to low cardiac output. Group II had improvement in angina class and New York Heart Association (NYHA) Functional class, in immediate post-operative period, whereas improvement in angina class observed in Group I, during long-term post-operative follow-up. LVEF showed significant improvement Group I 59.4 (3.84) compared to Group II 52.88 (3) at 3 months follow-up. Cardiac enzyme levels were found to be significantly elevated in Group II at the time of discharge. Conclusion: In this study, we conclude that LIMA is a better conduit than rSVG for LAD in South Indian patients undergoing CABG, in terms of improvement in angina and NYHA functional class, cardiac enzyme status and LVEF, although rSVG may give early improvement of angina class and functional class, due to smaller caliber of native LAD in our patient population.