Histidine–tryptophan–ketoglutarate solution versus multidose cardioplegia for myocardial protection in cardiac surgeries: a systematic review and meta-analysis

BACKGROUND: Surgical procedures in the heart requires protection of the heart from ischemia–reperfusion injury. Cardioplegia is the primary myocardial protective method in use. Histidine–tryptophan–ketoglutarate (HTK) solution is an intracellular cardioplegic solution that was initially used to preserve organs for transplantation. METHODS: A systematic electronic search was conducted in July 2021, in four databases; PubMed, Scopus, Web of Science, and Cochrane Library for eligible randomized controlled trials. The results were screened and the eligible trials were identified. Thereafter, the relevant data were extracted and pooled as mean difference or risk ratio, and 95% confidence interval in an inverse variance method using RevMan software. RESULTS: This review included 12 trials (n = 1327). HTK solution has resulted significantly in shorter intensive care unit stay (MD = − 0.09; 95% CI [− 0.15, − 0.03], p = 0.006), and shorter hospital stay (MD = − 0.51; 95% CI [− 0.71, − 0.31], p < 0.00001). Moreover, the patients who received the HTK solution had significantly lower levels of creatine kinase (after 4–7 h (MD = − 157.52; 95% CI [− 272.31, − 42.19], p = 0.007), and 24 h (MD = − 136.62; 95% CI [− 267.20, − 6.05], p = 0.04)), as well as creatine kinase muscle brain band (after 44–48 h (MD = − 3.35; 95% CI [− 5.69, − 1.02], p = 0.005)). CONCLUSION: HTK solution had the same efficacy and safety as other cardioplegic solutions in most of the clinical parameters. Furthermore, the solution showed superiority in fastening the recovery and protecting the myocardium at the biochemical level. HTK solution provides longer myocardial protection; therefore, it limits surgical interruption. HTK solution can be used as an alternative to the currently used cardioplegic solutions.