The use of blood versus crystalloid cardioplegia in adult open heart surgery: A systematic review

Myocardial ischemia can occur due to hypotension, shock, coronary heart disease, and aortic cross-clamping during open-heart surgery using a cardiopulmonary bypass machine. Cardioplegia is classified into the blood or crystalloid base as a cardioprotective method. This systematic review and meta-analysis aimed to describe the effectiveness of blood and crystalloids cardioplegic solutions in adult open-heart surgery by focusing on their effects on cardiac enzymes. This study investigated the effect of blood and crystalloid cardioplegia on troponin (cTn) and creatinine kinase myocardial bound (CKMB). The literature search was carried out on several Cochrane, PubMed, PMC, and Google Scholar databases from January 2014 to August 2020 using the medical subject heading keywords and Boolean operator. We obtained 346 articles and identified nine prospective randomized studies from five countries that met the eligibility criteria. The majority discussed the comparison of blood cardioplegia and crystalloids in coronary revascularization cardiac surgery (CABG). The cTn values (weighted mean difference [WMD] –2.67, confidence interval [CI] –4.18 to 1.17, P = 0.0005) and CKMB values (WMD –2.67, CI –4.18 to 1.17, P = 0.0005) 24 h operatively showed that the level of the cardiac enzymes increased in the crystalloids cardioplegia group more than the blood cardioplegia group. Overall, the articles used have a low risk of bias despite their high level of homogenicity. The current literature on cardioplegia in adults does not provide adequate advanced-phase trials. Both types of cardioplegia provide reasonable protection for the myocardium. However, several studies reveal that crystalloid cardioplegia increases cardiac enzymes more significantly than blood cardioplegia.