Reoperation for coronary artery disease.

Repeat coronary artery bypass grafting (CABG) accounts for approximately 5% of all myocardial revascularization procedures in the United States annually; it is estimated that nearly 7000 reoperations will be performed in 1984. Angiographic indications for repeat CABG include primary bypass graft obstruction, progressive coronary arteriosclerosis, and combined graft failure and new coronary artery disease. Saphenous vein obstruction secondary to arteriosclerosis occurs in more than half the bypass grafts at 10 years after CABG. Successful aortocoronary reoperation is dependent on careful attention to special surgical technical considerations such as chest reentry, cardiopulmonary bypass management and myocardial preservation, primary graft handling and identification of the target coronary vessel, choice of available bypass conduits, completeness of revascularization, and hemostasis and blood conservation. Operative mortality for repeat CABG is approximately twice that for an initial aortocoronary bypass procedure. Overall operative morbidity is not significantly different for primary and subsequent myocardial revascularization. Five-year survival after repeat aortocoronary surgery is approximately 90% and compares favorably with survival rates after initial CABG. However, symptomatic relief of angina pectoris is not as effective after a repeat myocardial revascularization as it was after the first CABG; only half the patients are angina-free 5 years after reoperation. As with primary revascularization, long-term graft patency rates after coronary reoperation are superior for the internal artery as compared with the saphenous vein.