Comparative Effects of HTK and St. Thomas Cardioplegia on Myocardial Outcomes and Sodium Balance in Pediatric Tetralogy of Fallot Surgery.

Objective: This study aimed to evaluate the myocardial protective efficacy of different myocardial protection solutions used during extracorporeal circulation in pediatric patients undergoing surgery for complex congenital heart disease. The analysis focused on the effects of these solutions on perioperative cardiac rhythm and serum sodium levels.

Methods: A retrospective analysis was performed on clinical data from 60 pediatric patients who underwent surgery with extracorporeal circulation for complex congenital heart disease between January 2022 and October 2024. Patients were categorized into the St. Thomas cardioplegic solution group (n = 30) and the histidine-tryptophan-ketoglutarate (HTK) solution group (n = 30). Serum sodium levels and myocardial enzyme markers were monitored perioperatively. Additionally, the incidence of postoperative cardiac arrhythmia and the duration of cardiac reperfusion were recorded.

Results: No significant differences in serum sodium concentrations were observed between the groups preoperatively, or at 12 and 48 hours postoperatively (p > 0.05). However, intraoperative serum sodium levels at 30 and 60 minutes were significantly lower in the HTK solution group compared to the St. Thomas cardioplegic solution group (p < 0.05). Postoperative levels of creatine kinase-MB and B-type natriuretic peptide at 12 and 48 hours were significantly lower in the HTK solution group than in the St. Thomas cardioplegic solution group (p < 0.05). Additionally, the cardiac reperfusion duration was significantly shorter in the HTK solution group (p < 0.05). No significant difference was observed in the incidence of postoperative cardiac arrhythmia between the two groups (p > 0.05).

Conclusion: Compared with St. Thomas cardioplegic solution, the HTK solution was associated with significant intraoperative fluctuations in serum sodium concentrations, which stabilized postoperatively. HTK solution demonstrated improved myocardial protection as evidenced by reduced cardiac reperfusion time and lower postoperative myocardial enzyme levels, without an increased risk of postoperative cardiac arrhythmias.