Assessment of the myocardial protective effect of antegrade warm blood cardioplegia by measuring the release of biochemical markers

Intermittent warm blood cardioplegia has been reported as a valuable altern ative for myocardial protection in cardiac surgery; however, conflicting ex perimental data have been published. To assess the clinical effectiveness o f intermittent Harm cardioplegia, He measured the release of troponin-T (Tn -T), a highly sensitive and specific marker of myocardial damage, and creat ine kinase MB isoenzyme (CK-MB), in 12 patients who underwent elective coro nary artery bypass grafting (CABG) with antegrade intermittent warm blood c ardioplegia (37 degrees C) being the warm group, in comparison with 16 pati ents who underwent CABG with antegrade intermittent cold blood cardioplegia (4 degrees C) being the cold group. Blood samples wee taken to determine t he serum concentrations of CK-MB and Tn-T, at the induction of anesthesia, then 3, 6, 12, and 24 h after the termination of cardiopulmonary bypass (CP B). The peak increase in serum CK-MB levels, 3h after CPB, was significantl y lower in the warm group than in the cold group, at 27.8 +/- 7.8 IU/l vs 4 0.8 +/- 12.6 IU/l, respectively (P = 0.0042). The serum Tn-T 12 h after CPB was significantly lower in the warm group than in the cold group, at 1.40 +/- 0.71 ng/ml vs 2.06 +/- 0.95 ng/ml, respectively (P = 0.0-19), In conclu sion, intermittent antegrade warm blood cardioplegia showed effective myoca rdial protection in elective CABG.