Efficacy and short-term outcomes of myocardial protection using single-dose histidine-tryptophan-ketoglutarate cardioplegia during aortic root surgery with different duration of myocardial ischemia

Abstract

Objective: To explore the efficacy of myocardial protection with single-dose histidine-tryptophan-ketoglutarate (HTK) cardioplegia during aortic root operation, and the correlation between short-term clinical outcomes and duration of myocardial ischemia. Methods: The data of clinical cases undergoing myocardial protection with single-dose HTK cardioplegia during aortic root operation from January 2018 to December 2022 were retrospectively reviewed. Patients were divided into conventional HTK cardioplegia group (<3 h) and prolonged HTK cardioplegia group (≥3 h) according to duration of intraoperative myocardial ischemia. A 1∶1 propensity score matching was performed and the correlations between duration of myocardial ischemia and postoperative short-term outcomes (30-day mortality, readmission, mechanical circulation support and renal insufficiency) were analyzed. Results: A total of 282 patients were included in the final analysis, with 210 cases in the conventional HTK cardioplegia group and 72 cases inthe prolonged HTK cardioplegia group before matching. After matching, there were 64 cases (53 males and 11 females) in the conventional HTK cardioplegia group, with a mean age of (49.4±14.2) years. The prolonged HTK cardioplegia group had 64 cases (55 males and 9 females), with a mean age of (50.5±12.3) years. Higher sensitivity troponin [12 h: 10.1 (4.6, 18.7) μg/Lvs 4.1(2.2, 8.6) μg/L, P=0.002; 24 h: 7.7 (4.5, 19.0) μg/L vs 4.8 (2.2, 11.9) μg/L, P=0.025] and creatine kinase isoenzyme[12 h: 46.3 (28.1, 62.4) μg/L vs 20.7(14.1, 32.9) μg/L, P<0.001; 24 h: 26.3(13.4, 49.2) μg/L vs 14.5 (10.1, 33.5)μg/L, P=0.011] after surgery was detected in prolonged HTK cardioplegia group. Comparisons of other primary and secondary endpoint events showed no significant differences between the two groups (all P>0.05). Multivariate binary logistic regression showed that duration of myocardial ischemia had no significant effect on postoperative 30-day mortality (OR=1.255, 95%CI: 0.500-3.148, P=0.629), 30-day readmission (OR=0.378, 95%CI: 0.069-2.065, P=0.261) and mechanical circulation support (OR=0.991, 95%CI: 0.331-2.970, P=0.998). Conclusion: During aortic root surgery, single-dose HTK cardioplegia may provide satisfactory myocardial protection, and there was no significant correlation between duration of myocardial ischemia and short-term clinical outcomes.