RESULTS OF CORONARY SURGERY - A 20 YEARS EXPERIENCE

Background: Since the first surgical coronary revascularization done i n Chile in 1971, 5000 such procedures have been performed. Aim: To ass ess the long term results of coronary revascularization surgery in our institution and to identify prognostic factors. Patients and methods: Five groups of 100 patients each, composed by the first consecutive p atients subjected exclusively to coronary bypass surgery, in the years 1975, 1980, 1985, 1990 and 1995 were retrospectively studied. Results : Mean age of patients increased from a median of 52 years old in 1975 to 62 years old in 1995. No changes in the frequency of diabetes, hyp ertension, high serum cholesterol or previous myocardial infarction we re observed. There was an increase in the proportion of patients with a recent (<30 days) infarction that were operated along time. Seventy percent of patients had triple vessel disease or LMT and this proporti on did not change. The number of grafts per patients increased form 1. 9 to 3.4 and the use of arterial conduits from 0.18 to 0.81. Periopera tive mortality remained constant and was 1.6%. Follow up information w as obtained for 93% of 492 survivors. Actuarial survival at 5, 10, 15 and 20 years was 93+/-1, 82+/-2, 62+/-3 and 41+/-4% respectively. Nine ty eight +/-0.7, 89+/-2, 73+/-4 and 65+/-5% of patients remained free of a new myocardial infarction in the same lapses, respectively. Ninet y seven +/-1, 94+/-2, 76+/-4 and 47+/-7% of patients remained free of a new operation. Stepwise logistical regression analysis identified as bad prognostic factors, in decreasing order: cardiac failure, diabete s, smoking, hypercholesterolemia and age at the moment of operation. C onclusions: Coronary artery bypass surgery provides good and long last ing clinical improvement. The prognosis of patients is influenced by t he presence of cardiac failure some well known coronary risk factors a nd age at the moment of operation.