Release of cardiac troponin I in antegrade crystalloid versus cold blood cardioplegia

Abstract

Objective: The purpose of this study was to assess the efficacy of myocardial protection, comparing antegrade crystalloid cardioplegia with cold blood cardioplegia, in patients with preserved left ventricular function who were undergoing elective first coronary artery bypass grafting, Release of cardiac troponin I was used as a marker for the effectiveness of myocardial protection, Methods: A consecutive series of 62 patients were randomly assigned to receive crystalloid or blood cardioplegia, Cardiac troponin I concentrations were determined in venous blood samples before the operation, immediately after unclamping, at 6, 9, 12, and 24 hours, and daily thereafter for 5 days, Results: Rising levels of troponin I were found in all patients. The time course and peak release were similar in the crystalloid cardioplegia and the blood cardioplegia groups. No patients in either group had electrocardiographic evidence of perioperative myocardial infarction, Cardiac troponin I was able to detect small areas of myocardial damage, not revealed by electrocardiography or creatine kinase MB release, Aprotinin administration was associated with lower cardiac troponin I release in both groups, Cardiac troponin I was lower in patients whose conditions did not require electrical defibrillation after aortic unclanlping, irrespective of cardioplegia type. The presence of a main stem lesion was associated with higher cardiac troponin I release only in the crystalloid cardioplegia group. Conclusions: Antegrade cold blood cardioplegia is equally effective as antegrade crystalloid cardioplegia in a randomized group of patients with preserved left ventricular function who were undergoing elective first coronary artery bypass grafting, Aprotinin administration resulted in lower cardiac troponin I release, whereas electrical defibrillation was related to a higher release irrespective of cardioplegia type, The presence of a main stem lesion resulted in higher cardiac troponin I release in the crystalloid cardioplegia group.