Conduit Selection for Improved Outcomes in Coronary Artery Bypass Surgery

Abstract

Coronary artery bypass grafting (CABG) is one of the most studied operations in medical history, but many of the data forming the basis for clinical decisions in patients with coronary artery disease (CAD) were derived in the 1970s and 1980s, when the procedure and medical therapy were in their relative infancy. Advances in medical therapy (beta adrenergic blockers, thienopyridines, statins, and others), percutaneous coronary interventions (PCI), and surgical techniques have changed the decision making for patients with CAD. In addition, patient populations referred for surgery have changed since the original studies documenting advantages of CABG over other forms of therapy. Since percutaneous transluminal coronary angioplasty (PTCA) was introduced, significant advances have been made in the percutaneous treatment of CAD. When drug-eluting stents (DES) were introduced in the early 2000s, many predicted the demise of CABG surgery. Enthusiasm for percutaneous treatment of CAD has most recently led to promoting PCI for unprotected left main coronary artery (LMCA) disease, an anatomical state typically reserved for CABG [1-3]. Percutaneous options have indelibly changed the face of CABG surgery and raise questions concerning the “gold standard” of care in coronary revascularization. For instance, recent reports document that patients referred for redo coronary artery surgery have declined, presumably due to the increased enthusiasm, possibly among surgeons themselves, for PCI in this setting [4]. Despite this, few studies have actually compared PCI with CABG. Two notable studies are recently available, both demonstrating advantages for CABG over PCI for left main CAD and/or three-vessel CAD [5, 6]. Concurrently, details pertaining to short-term outcomes of CABG have been questioned. For example, historical saphenous vein graft (SVG) patencies were reported as approximately 50% at 10 years [7]. However, several studies published in the mid-2000s indicate that earlyterm patencies of aorto-coronary SVG conduits are not as good as the historical figures that are still often quoted [8-10]. While the long-term patency and performance of the left internal mammary artery (LIMA) has not been questioned, the recent poor performance of