INTERMITTENT ANTEGRADE CARDIOPLEGIA - WARM BLOOD VS COLD CRYSTALLOID - A CLINICAL-STUDY

Intermittent antegrade warm blood cardioplegia (IAWBC) is a not usual technique of myocardial protection. We propose a delivery protocol tha t standardizes the length of ischemic intervals, duration of each card ioplegic dose and K+ amount. Cardioplegia is represented by blood, tak en from the oxygenator and injected directly into the aortic root, and K+, added by means of a syringe pump. We reviewed the first 300 patie nts who underwent elective or urgent coronary artery by-pass procedure s (group A) and compared them with the last 300 patients operated on w ith intermittent antegrade cold crystalloid cardioplegia (group B). Th e overall mortality in group A was lower than in group B (0.7 vs 3.0, p < 0.05); there was no in-hospital death in patients with poor left v entricle (LVEF < 35%) in group A (0/64 vs 3/59, P < 0.025). Reduction of mortality was due to a drastic fall of morbidity. In group A no pat ients needed circulatory assistance (13 in group B, p < 0.0005) or int raortic ballon pumping (9 in group B, p < 0.005) in operating room or in intensive care unit (ICU); only 1 patient had inotropic drug (29 in group B, p < 0.0005) and only 6 needed lignocaine infusion (27 in gro up B, p < 0.0005). Incidence of postoperative myocardial infarction wa s lower in group A (4 vs 9 in group B) as well cerebrovascular acciden ts (4 vs 10 in group B), but difference was not statistically signific ant. CK-MB peaks were higher in group B, both in absolute values (59 /- 39 vs 37 +/- 38 in group A, p < 0.0005) and in CK percentage (9.3 /- 5.0 vs 6.1 +/- 2.5 in group A). Warm patients awoke earlier than co ld patients (2.52 +/- 1.4 hours vs 4.6 +/- 3.2 hours, p < 0.0005) and had a shorter ICU stay (26 +/- 7 hours vs 41 +/- 11 hours, p < 0.0005) . We conclude that intermittent antegrade warm blood cardioplegia is a reliable and effective technique of myocardial protection and, in cor onary artery surgery, gives superior results than intermittent antegra de cold crystalloid cardioplegia.