OBJECTIVE: To compare the tradicional myocardial protection achieved by crystalloid cold cardioplegia, which is induced through the aortic root, associated to systemic hypothermia and intermitent aortic cross-clamping (Group I) to warm blood cardioplegia using induction through the aortic root but retrograde maintenance through the coronary sinus, associated to systemic normothermia. METHODS AND MATERIAL: During the period ranging from May 1992 to May 1994, two groups of 50 patients were selected consecutively, but not randomized, according to requirements that increased the morbidity and mortality associated to the Coronary Artery Bypass Graft (CABG). All selected patients presented at the time clinical instability, more than three coronary arteries (or the left main coronary artery) occluded or severely suboccluded, associated with severe LV dysfunction of ischemic ethiology. RESULTS: The two groups were comparable according to the variabilities found in the period just prior to the surgery. Group II had a larger amount of grafts (3.82x3.40), consequently a longer period of aortic cross-clamping (70.74x62.06 min) and a longer time in cardiopulmonary bypass (CPB) (97.5x93.8 min). Group I, in average, needed more inotropic agents for the weaning process from CPB, more use of mechanical assist devices and showed a bigger incidence of acute myocardial infarction as well as ventricular fibrilation after aortic cross-clamp release. This group also had less incidence of prolonged mechanical ventilation, greater early and global mortality, and also a larger number of deaths due to other cardiac causes. CONCLUSION: The two groups were not comparable due to the larger number of grafts in Group II turning them more critical than Group I. Nervertheless, the results from Group II were superior to Group I, even though the statistic analysis do not corroborate those results. That, associated with clinical data, technical improvement and recognizing the limitations of the procedure, made us use it in this specific group of patients.
Heart arrest, induced; Myocardial revascularization; Myocardial revascularization