Efficacy of Single-Dose Del Nido Cardioplegia Beyond 90 Minutes in Adult Cardiac Surgery

Abstract

Background: Del Nido (DN) cardioplegia is widely used in cardiac surgery for its efficacy in providing myocardial protection for up to 90 min with a single dose. However, its safety and efficacy during prolonged ischemia remain unclear. Methods: This retrospective study analyzed 471 patients who underwent cardiac surgery with CPB between January 2019 and September 2024. Patients were divided into two groups: ACC durations of 60-90 min (Group A, n = 240) and >90 min (Group B, n = 231). The perioperative characteristics, clinical outcomes, and biochemical markers were compared to evaluate the impact of prolonged ischemia. Results: Patients in Group B exhibited significantly higher postoperative troponin I and lactate levels at 4 h post-CPB, suggesting increased myocardial and metabolic stress. Lactate levels normalized within 24 h, indicating transient myocardial dysfunction. Defibrillation requirements and vasoactive inotropic score (VIS) were also significantly elevated in Group B, reflecting compromised myocardial electrical stability and hemodynamic challenges. However, the long-term outcomes such as mortality, LCOS, and MODS showed no significant differences between the groups. Conclusions: While DN cardioplegia provides sufficient myocardial protection for ACC durations within 90 min, its efficacy diminishes during prolonged ischemia, as evidenced by increased myocardial injury and hemodynamic instability. Tailored strategies, including standardized redosing protocols and enhanced perioperative management, are essential for optimizing outcomes in complex surgeries with extended ischemia times. Further prospective studies are needed to refine these protocols and assess alternative solutions for myocardial protection.

Keywords: cardioplegia; del Nido cardioplegia; ischemia–reperfusion injury; myocardial protection.

Figure 1

Graphical representation of the study design for patients undergoing cardiac surgery using a single dose of del Nido (DN) cardioplegia with aortic cross-clamp times of 60–90 min and 90 min or more. The number of patients was reduced to 471 using propensity score matching.

Figure 2

The box-plot graph comparing postoperative vasoactive–inotropic score (VIS) between the groups showed that VIS, reflecting cumulative inotropic support, was significantly higher in Group B. * p < 0.05.

Figure 3

(a,b) Scatter plot graphs revealing (a) early (4 h) and (b) late (24 h) postoperative lactate levels: early postoperative lactate levels were significantly higher in Group B (p < 0.001), although they equalized within 24 h in both groups.

Figure 4

Box-plot graph comparing troponin I (Trop-I) levels in the first 24 h postoperatively in both ischemic time intervals: TnI levels were significantly higher in the group with an aortic cross-clamping time >90 min in the postoperative first 24 h. * p < 0.05.