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Coronary artery bypass grafting (CABG) is a major surgical procedure in which atheromatous blockages in a patient’s coronary arteries are bypassed using harvested venous or arterial conduits. The bypass restores blood flow to the ischemic myocardium, which, in turn, restores function, viability, and relieves anginal symptoms. Almost 400,000 CABG surgeries are performed each year, making it the most commonly performed major surgical procedure, but surgical trends have declined as the use of alternative options, such as medical treatment and percutaneous coronary intervention (PCI), has increased. This activity illustrates the indications for coronary artery bypass and highlights the interprofessional team's role in managing patients with CAD. Objectives: Identify the anatomical structures, indications, and contraindications of coronary artery bypass grafting. Describe the equipment, personnel, preparation, and technique in regards to coronary artery bypass grafting. Outline the potential complications of coronary artery bypass grafting. Review interprofessional team strategies for improving care coordination and communication to advance coronary artery bypass grafting and improve outcomes. Access free multiple choice questions on this topic.

Coronary artery bypass grafting (CABG) is a major surgical procedure in which atheromatous blockages in a patient’s coronary arteries are bypassed using harvested venous or arterial conduits. The bypass restores blood flow to the ischemic myocardium, which, in turn, restores function and viability and relieves anginal symptoms. Almost 400,000 CABG surgeries are performed each year, making it the most commonly performed major surgical procedure, but surgical trends have declined as the use of alternative options, such as medical treatment and percutaneous coronary intervention (PCI), has increased.[1] In general, on-pump and off-pump are the 2 types of CABG, with the difference being the use of a cardiopulmonary bypass circuit and an arrested heart during an on-pump CABG. The conduits used as bypass grafts are routinely the left internal mammary artery (LIMA) and saphenous vein grafts (SVGs) from the lower extremities. Other conduits that may be grafted include the right internal mammary artery (RIMA), the radial artery, and the gastroepiploic artery. The type and location of the grafts depend on the patient’s anatomy and the occluded arteries. Typically, the LIMA is grafted to the left anterior descending (LAD) artery, and the other conduits are used for the other occluded arteries.[2]

The complications of CABG include stroke, wound infection, graft failure, renal failure, postoperative atrial fibrillation, and death.  The stroke rate of CABG has been reported at 1% to 2%, depending on the characteristics of the patient and their risk factors for stroke, including advanced age, prior stroke, aortic atherosclerosis, peripheral arterial disease, perioperative atrial fibrillation, and diabetes.[3] Sternal wound infection rates are about 1% and depend on risk factors such as obesity, diabetes, chronic obstructive pulmonary disease (COPD), and prolonged surgery.[2][4] Saphenous vein graft (SVG) failure is most common within 30 days of operation and is dependent on several factors, including vein size and excessive length, distal runoff and slow flow, and hypercoagulability and thrombosis. Rates of SVG failure up to 25% have been seen with repeat angiography after CABG.[2] Alternatively, arterial grafts such as the left internal mammary artery (LIMA) and radial arterial grafts remain patent longer and have patency rates exceeding 90% at 10 years.[2] Postoperative renal dysfunction rates after CABG range from 2% to 3%, with 1% requiring dialysis. Risk factors are multifactorial but include preoperative renal disease, advanced age, diabetes, type of surgery, LV dysfunction, and shock. No medications have been definitively shown to reduce the rates of CABG-induced renal dysfunction, but there may be an advantage of off-pump CABG over on-pump CABG.[2][5] Atrial fibrillation within the first 5 days after CABG is relatively common, with rates of 20% to 50%, and is associated with increased morbidity, with a higher risk of embolic stroke postoperatively, as well as increased mortality. Preoperative treatment with beta-blockers and possibly amiodarone has been shown to be the most effective way to reduce the incidence of postoperative atrial fibrillation.[2] The risk of perioperative death after CABG is dependent on co-morbidities, the urgency of the surgery, and the case-volume of the center where the operation takes place, ranging from 1% to 2%.[2]

Coronary artery bypass grafting requires a large, well-trained, and experienced team to reduce the procedure's morbidity and mortality and improve outcomes.  Studies have shown that improving communication, collaboration, and teamwork among team members can improve outcomes and increase patient safety.[6]