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Coronary artery disease is the leading cause of death worldwide, and coronary artery bypass graft is considered the mainstay for the treatment of severe multi-vessel coronary artery disease. The internal mammary artery is the gold-standard bypass conduit and is associated with significant improvement in short and long-term outcomes and survival of patients. This activity describes the coronary artery bypass graft surgery using the internal mammary artery and highlights the role of the interprofessional team and multidisciplinary approach in optimizing the management of patients undergoing this complicated procedure. Objectives: Identify the clinical benefits of internal mammary artery-coronary artery bypass grafting surgery. Describe the equipment, personnel, preparation, and technique in regards to internal mammary artery bypass. Explain the appropriate evaluation of the potential complications and their clinical significance with internal mammary artery bypass. Outline interprofessional team strategies for improving care coordination and communication to advance internal mammary artery bypass and improve outcomes. Access free multiple choice questions on this topic.

The mainstay for the treatment of multi-vessel severe coronary artery disease is coronary artery bypass graft (CABG) surgery. Various grafts and conduits have been used and were studied to optimize surgical outcomes.[1] The internal mammary artery (IMA) is the gold-standard conduit and associated with significant improvement in short and long-term outcomes and survival of patients undergoing CABG surgery.[2][3][4] The saphenous vein graft (SVG), also commonly used in CABG procedure, is prone to early atherosclerotic changes that lead to obstruction. Therefore it is considered inferior to the IMA conduit in terms of long-term patency rates. In comparison to SVGs, the long-term patency rate of IMA bypass conduits is very high, and around 90% of grafts remain free of significant stenosis at ten years.[5] Loop et al. published 10-year survival of patients who received an IMA graft to the left anterior descending coronary artery with or without one or more vein grafts versus patients who received only SVGs, which showed that the survival was higher with an IMA graft (93.4%) versus SVG (88.0%) for those with the one-vessel disease, 90.0% versus 79.5% for two-vessel disease, and 82.6% versus 71.0% (P<0.0001) for those with three-vessel disease. Since then, the IMA has become the preferred choice for grafting the left anterior descending coronary artery in CABG.[2] Specific physiological, anatomic, and hemodynamic characteristics of IMA graft make it a suitable conduit and less prone to early atherosclerotic changes.[6] We will discuss the anatomy of IMA, the surgical technique of IMA grafting, its complications, and clinical significance.[7]

Complications during and after the coronary artery bypass grafting (CABG) in general include Perioperative hemorrhage Perioperative myocardial infarction Renal dysfunction Arrhythmias Cerebrovascular accidents (CVA) Cardiac tamponade Respiratory tract infection Sternotomy wound infection Graft failure. Cerebrovascular accidents are reported in about 1% of patients having IMA bypass graft and mainly determined by underlying risk factors, including diabetes mellitus, advanced age, prior CVA, aortic atherosclerosis, and peripheral arterial disease.[14] Although the sternal wound infection rate has significantly reduced, however, it is relatively more common in patients with obesity, diabetes mellitus, and advanced age.[15] The most common perioperative arrhythmia is atrial fibrillation, which can be managed with beta-blockers, amiodarone, and anticoagulation. It is associated with embolic stroke and increases perioperative mortality.

The coronary artery bypass graft (CABG) is a complicated surgical procedure that requires operative skills and expertise as well as good perioperative care. Therefore it is necessary to have a system to ensure the completion of all aspects of patient care. In pre-operative care, in addition to discussing the risks and benefits of the procedure with the patient and family, the assessment must be done to ensure that patient meets the recommended criteria for the procedure. Proper sterile technique is fundamental to better outcomes. In the postoperative period, patients need regular monitoring by trained nursing staff for complications. After recovery, every patient should undergo cardiac rehabilitation. It is now recommended to have a multidisciplinary team approach that may include a primary care provider, intervention cardiologist, cardiac surgeon, cardiac rehabilitation specialist, a cardiac nurse, and a cardiac pharmacist to enhance patient care, optimize procedural success and minimize perioperative complications.