RESUMO
OBJECTIVE: To compare 4 methods of myocardial protection in GABG in terms of markers of myocardial ischemia, mortality, morbidity and mid-term results. MATERIAL & METHODS: Retrospective study of 241 consecutive patients undergoing isolated > 1 CABG using one of 4 methods: off-pump (OFF, n = 108), cardiopulmonary bypass (CPB) and cardioplegia (CARD, n = 66), CPB and beating heart (BEAT, n = 47), or CPB and ventricular fibrillation (FIBR, n = 20). Mean age was 65.7 +/- 9.3 years and mean EuroSCORE was 3.2 +/- 2.3. The groups were similar in terms of age, gender distribution, body mass index, incidence of smoking, hypertension, renal insufficiency, CCS class, ventricular function and mean EuroSCORE. Serial blood samples were collected for CK-MB and troponin T, preoperatively and 1, 6, 12 and 24 hours after the procedure. RESULTS: Mean number of distal anastomoses was 3.27 BEAT, 2.98 CARD, 2.90 FIBR and 2.55 OFF (p < 0.05 OFF vs. the other 3 groups). Six patients died in hospital (2.5%), 2/47 BEAT (4.2%), 1/66 CARD (1.5%), 1/20 FIBR (5.0%), 2/108 (1.9% OFF) (p = 0.1). The incidence of atrial fibrillation, stroke/TIA and blood transfusion and length of stay were similar between groups (p = 0.1) but there was a tendency for increased incidence of Q-wave MI (p = 0.08) in OFF and combined adverse events in FIBR (p = 0.07). At 12 hours postoperatively, CK-MB and troponin T were significantly higher in FIBR than in CARD or OFF (p < 0.05) and at 24 hours, troponin T remained higher in FIBR than in all other groups (p < 0.05). After a mean follow-up of 19 months, no significant difference was observed between groups in mortality or relief of angina. CONCLUSION: We were unable to demonstrate the superiority of any one revascularization method over another in terms of mortality, morbidity or length of stay. As shown by lower levels of myocardial markers of ischemia, better myocardial protection was obtained with OFF, BEAT and CARD compared to FIBR. Mid-term survival and relief of angina were similar between groups.
