Tolga Onur BADAK, Hasan UNCU
The Atlantic Journal of Medical Science and Research - 2026;6(2):234-242
Aim: Adequate myocardial protection during cardiac surgery poses a particular challenge in patients with chronic total occlusion (CTO). This study evaluates the comparative efficacy of single-dose Del Nido cardioplegia (DNC) versus conventional blood cardioplegia (CBC) in patients undergoing coronary artery bypass grafting (CABG) for CTO, with emphasis on the modulatory role of coronary collateral development. Materials and Methods: A retrospective, non-randomized analysis was conducted on 250 consecutive patients who underwent isolated CABG for CTO between January 2018 and January 2026. Patients were stratified into two groups according to the cardioplegia method administered in routine clinical practice by the operating surgeon: DNC (n=128) and CBC (n=122). Primary endpoints included postoperative cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) levels. Collateral circulation was graded according to the Rentrop classification system. Results: Among patients with well-developed collaterals (Rentrop 2-3), the DNC group demonstrated significantly lower 24-hour cTnI levels compared with the CBC group (1.4 +/- 0.6 vs. 3.1 +/- 1.3 ng/mL, p<0.001), with a large effect size (Cohen's d = 1.65). This cardioprotective advantage was not observed in patients with poorly developed collaterals (p=0.124). In the overall cohort, the DNC group exhibited a lower requirement for inotropic support (18.8% vs. 32.0%, p=0.021) and a shorter hospital length of stay (6.8 +/- 2.4 vs. 8.2 +/- 3.1 days, p=0.035). Multivariate logistic regression identified CBC use (OR: 2.34, 95% CI: 1.28-4.27) and poor collateral development (OR: 3.12, 95% CI: 1.67-5.83) as independent predictors of postoperative myocardial injury. Conclusion: Single-dose DNC confers superior myocardial protection compared with CBC in CTO patients undergoing CABG; however, this benefit is contingent upon the presence of well-developed collateral vessels. These findings indicate that preoperative assessment of collateral circulation may serve as a valuable guide for individualized cardioplegia selection.
