Abstract

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

Key words: Coronary occlusion, coronary artery bypass, cardioplegic solutions, collateral circulation, myocardial reperfusion injury