3RD AND 4TH OPERATIONS FOR MYOCARDIAL-ISCHEMIA - SHORT-TERM RESULTS AND LONG-TERM SURVIVAL

Background An increasing number of patients having at least two operat ions for myocardial ischemia are now presenting for a third or fourth procedure. We report the Mayo Clinic experience with repeated reoperat ive surgery for coronary artery disease. Methods and Results We have e valuated 67 consecutive patients (54 men, 13 women) during a 14-year p eriod (1978 to 1992). The mean age at the third procedure (n=63) was 6 3.4 years and at the fourth procedure (n=4) was 70.6 years. Clinical i ndications for surgery were unstable angina in 29 patients (43%), New York Heart Association class In angina in 36 (54%), non-Q wave acute m yocardial infarction in 1, and acute pulmonary edema in 1. Urgent or e mergency surgery was undertaken in 17 patients (25%). All patients had triple-vessel disease, and 20 (30%) had left main coronary artery ste nosis >50%. The mean ejection fraction in 56 patients was 0.56 +/- 0.1 1. Occlusion or significant stenoses of preexisting saphenous grafts w ere thought to be the major cause of recurrent ischemia in 64 patients (96%). Only 14 patients (21%) had received previous arterial grafts. An average of 2.4 grafts was placed, and a new internal mammary artery was used on 47 occasions. Eight patients (11.9%) died. Three patients required a left ventricular assist device, and one of them survived. There were 21 late deaths: 8 were cardiac and 5 were likely to be card iac. Five-year and 10-year survival in all patients was 75.6% +/- 5.3% and 47.9% +/- 7.7%, respectively. Freedom from further intervention f or hospital survivors at 5 and 10 years was 88.4 +/- 4.5 and 72.3 +/- 8.5%, respectively. Of the 38 patients still alive at last follow-up, 29 (76%) were considered to be in New York Heart Association functiona l class I or II. On univariate analysis, use of an intra-aortic balloo n pump, prolonged bypass time, left main coronary artery stenosis >50% , and a surgeon's impression of angiographic inoperability correlated with increased risk of early mortality. Conclusion We conclude that in a select group of patients, repeated reoperative surgery, despite an increased mortality, can result in good long-term survival and signifi cant improvement in clinical status.