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Coronary artery surgery is performed because coronary artery disease remains a significant cause of morbidity and mortality. Variations in technique are possible, including the use of cardiopulmonary bypass and conduit choice. Main repair indications include left main disease, left main equivalent disease, and multivessel disease in a diabetic patient. This activity reviews the evaluation and surgical treatment of coronary artery disease and highlights the role of the interprofessional team in evaluating and treating this condition. Objectives: Identify indications for coronary artery surgery. Explain the variations in technical options for coronary artery surgery, especially regarding conduit choice. Summarize complications relevant to coronary artery surgery. Review the importance of improving care coordination amongst the interprofessional team to enhance the delivery of care for patients in need of coronary artery surgery. Access free multiple choice questions on this topic.

Treating coronary artery disease (CAD) has been a published concern of the medical community since at least 1816 with Samuel Black’s autopsy correlations between coronary calcification and angina pectoris.[1] Initial surgical treatments were adventurous, ranging from sympathectomy to reduce angina symptoms, thyroidectomy to reduce myocardial hormonal stimulation, internal mammary artery ligation to augment hypothetical collateral vessel flow, abrasion of the pericardium to induce neovascularization, and ligation of the coronary sinus venous outflow, but none of these achieved clear success or widespread use. Three other early coronary artery surgical procedures achieved some prominence and are worth noting. The Beck II procedure after Johns Hopkins surgeon Claude Beck involved a staged conduit anastomosis between the aorta and the coronary sinus. The Vinberg procedure popularized by McGill surgeon Arthur Vinberg was the implantation of the internal mammary artery into the anterior left ventricular myocardium. Coronary endarterectomy (CE), first performed by William Longmire in 1958, is direct removal of atherosclerotic plaque from the coronary artery, similar to the procedure currently employed for carotid arteries.[1] Further development of coronary artery surgery is traced through Alexis Carrel’s pioneering work on arterial anastomosis culminating in the 1912 Nobel Prize and later collaboration with Charles Linberg on a model for a heart-lung machine in the 1930s. The maturation of cardiopulmonary bypass through the works of John Gibbon, John Kirklin, and others enabled a motionless, bloodless surgical field for the construction of reliable anastomoses, setting the stage for the explosive development of coronary artery bypass grafting (CABG) in the late 1950s and 1960s. Many CABG pioneers have staked claims to the development of the procedure, including Robert Goetz, Rene Favoloro, Vasilii Kolesov, Michael Debakey, and David Sabiston.[1][2]

Further development of coronary artery surgery is traced through Alexis Carrel’s pioneering work on arterial anastomosis culminating in the 1912 Nobel Prize and later collaboration with Charles Linberg on a model for a heart-lung machine in the 1930s. The maturation of cardiopulmonary bypass through the works of John Gibbon, John Kirklin, and others enabled a motionless, bloodless surgical field for the construction of reliable anastomoses, setting the stage for the explosive development of coronary artery bypass grafting (CABG) in the late 1950s and 1960s. Many CABG pioneers have staked claims to the development of the procedure, including Robert Goetz, Rene Favoloro, Vasilii Kolesov, Michael Debakey, and David Sabiston.[1][2] Coronary artery surgery in contemporary practice is mostly confined to coronary artery bypass grafting (CABG), although some groups are reexploring the use of coronary endarterectomy (CE). The procedural discussion of CABG is also covered elsewhere.[3] This article will focus more on consensus CABG recommendations and outcomes. Traditionally, the category “coronary artery surgery” excludes catheter-based endoluminal percutaneous coronary interventions (PCI), as discussed elsewhere.[4] The category “coronary artery surgery” may encompass traumatic disease of the coronary vessels, whether iatrogenic, blunt, or penetrating traumatic, but these conditions are rare. Standard treatment consists of observation, catheter-based therapy, direct repair (i.e., sew the hole shut), or CABG. Management depends on patient stability and anatomy, the bypassing proximal lesions, while distal lesions may even be ligated if their contribution to overall myocardial perfusion is limited.[5][6][7][8]

CABG outcomes are well studied; the Society of Thoracic Surgeons (STS) database and other organizations have been logging and reporting procedural outcomes for over thirty years, and it remains a class 1 recommendation that all CABG programs should participate in a larger registry to receive reports regarding their outcomes and generate improvement.[13] Summary of CABG complications is also covered elsewhere.[3] Although CABG brings an overall long-term mortality benefit to patients fitting indications for CABG, there is an upfront operative mortality risk after CABG. The rates reported in the FREEDOM and SYNTAX trials are consistent with standard mortalities, reported to be 1.7% and 3.5%, respectively.[27][28][27] The one-year mortality rate is close to 6 to 8%; the rate at three years is between 11 and 23%.[29][30][29] Emergent operation, need for reoperation, and shock increase this upfront mortality risk, but by two years post-surgery, such patients do as well as other CABG patients.[30] Cardiac complications occur with CABG. Myocardial infarction may occur, as well as initial low cardiac output states requiring inotropes and/or intra-aortic balloon pump support to maintain systolic pressures >90mmHg. Post-operative atrial fibrillation, which occurs in 20 to 50% of patients postoperatively is not benign, increasing mortality three-fold and disabling stroke four-fold, hence the recommendations for pharmacologic prophylaxis.[13] Stroke remains a particular Achilles heel of CABG surgery, with an incidence of 1.4% to 3.8%, in addition to adding a ten-fold increase in mortality. Etiologies include embolization from aortic cannulation, microemboli from cardiopulmonary bypass, and the potential for low flow hypoperfusion of borderline ischemic brains. Prevention strategies include optimal medical therapy, carotid endarterectomy for patients meeting indications, and operative adjuncts such as epiaortic ultrasound and transesophageal echocardiography (TEE) to guide aortic cannulation.[13]

Stroke remains a particular Achilles heel of CABG surgery, with an incidence of 1.4% to 3.8%, in addition to adding a ten-fold increase in mortality. Etiologies include embolization from aortic cannulation, microemboli from cardiopulmonary bypass, and the potential for low flow hypoperfusion of borderline ischemic brains. Prevention strategies include optimal medical therapy, carotid endarterectomy for patients meeting indications, and operative adjuncts such as epiaortic ultrasound and transesophageal echocardiography (TEE) to guide aortic cannulation.[13] Acute kidney injury reportedly occurs in 2 to 3% of CABG patients, with 1% requiring dialysis; this is hypothesized to result from hypoperfusion, cardiopulmonary bypass inflammatory states, and possibly low hematocrit levels.[13] Bleeding during and after CABG remains a common problem, often stemming from required anticoagulation for cardiopulmonary bypass. However, transfusions can cause myocardial depression and represent an increased mortality risk.[13] The sternal wound is a dreaded complication in CABG patients. Superficial wound incidence is reported 2 to 6%, with a deeper wound incidence of 0.5 to 5%, adding a mortality risk of 10 to 47%. Such wounds are not surprising given the internal mammary artery side branches provide 90% of the blood flow to the region. When harvesting the mammary artery, much of this perfusion is lost.[13] People with diabetes are especially prone to wound healing issues, hence the emphasis on optimal perioperative glycemic control.

An endeavor as complex as coronary artery surgery demands attention to non-technical aspects such as teamwork, communication, human factors, culture of safety, and optimizing the operative environment. There are increasing data and consensus that focus on these issues is needed to achieve and maintain high-quality interventions.[35]

A large team of professionals is required to not only manage the patient but to be in constant communication with each other to provide the best overall outcome. Coronary artery surgery requires a cardiothoracic surgeon, a first assistant, a pharmacist, a team of nurses, a perfusionist, an anesthesiologist or nurse anesthetist, and scrub techs in the perioperative period. As mentioned above, each of these team members plays a specific part in monitoring the patient. Though these members are crucial during the actual operation, so many more members are also vital in the pre-operative and post-operative stages of the patient. Monitoring the patient is just as important as it is in the intra-operative stage as it is in the pre- and post-operative stages. Those involved outside of the intra-operative stage include a cardiologist, ICU, and floor nursing staff, echo techs, physical therapists, and cardiac rehabilitation specialists. Nurses are critical in the care of post-op CABG patients. They are responsible for managing all drains, lines, and educating the patient and their family regarding post-operative care. Excellent perioperative care is crucial to the success and outcomes of the patient. Interprofessional team management and interventions made collectively as a team provide the best outcomes for CABG patients.

It is the responsibility of every member involved in a CABG to monitor the patient for possible complications that can occur. Team members should monitor the sternotomy incision site and vein harvest site for signs of a hematoma or excessive bleeding, the quality and quantity of the chest tube output, and any other complications that may occur.