Coronary artery bypass surgery is recommended to improve survival in left main disease, but is generally reserved for symptom relief after medical therapy failure in patients with EF >40%.
Does coronary artery bypass surgery improve survival or symptoms compared to medical therapy in patients with coronary artery disease?
Coronary artery bypass surgery provides a clear survival benefit in left main disease, while its primary role in other CAD subsets is symptom relief after the failure of aggressive medical therapy.
Patients with single-vessel disease, with normal or mildly abnormal ventricular function (EF greater than 40%), have a good prognosis both for natural survival and long-range symptomatic improvement; therefore medical therapy is strongly recommended. Surgery is considered only if symptoms persist after aggressive medical therapy. It is possible that single-vessel left anterior descending disease is a special variant of this group, and surgery may, with further reports, show an increased survival. However, no adequately designed study has yet suggested this, and it is currently our opinion that patients with single-vessel disease do not have an improved survival following surgery. It is not clear whether surgery improves survival in patients with multivessel disease and normal or mildly abnormal ventricular function (EF greater than 40%). Consequently, cardiologists are divided as to whether to advise surgery in these patients solely for survival. Currently, it is our opinion that these patients should have surgery only for improvement of symptoms after failure of medical therapy. In left main coronary disease the evidence favoring improved survival after surgery has convinced most cardiologists, including ourselves, to recommend surgery. Patients with poor ventricular function (EF less than 30%) secondary to coronary artery disease often have congestive heart failure and not angina as their chief symptom. Surgery is usually not advisable for these patients, because of the increased operative mortality and lack of improvement in ventricular function. Patients with poor ventricular function with angina are not usually significantly improved by surgery. In patients with moderately abnormal ventricular function (EF = 30-40%), relief of angina is frequently obtained, but with some added surgical risk. We recommend surgery in these patients after aggressive medical therapy has failed. Patients with unstable angina are initially medically stabilized, after which they are generally managed as stable angina. Patients with persistence of pain at rest in spite of vigorous medical therapy are usually managed by early catheterization and surgery.
Mullins et al. (Tue,) conducted a review in Coronary artery disease. Coronary artery bypass surgery vs. Medical therapy was evaluated. Coronary artery bypass surgery is recommended to improve survival in left main disease, but is generally reserved for symptom relief after medical therapy failure in patients with EF >40%.