Modified Del Nido Cardioplegia and Its Evaluation in a Piglet Model

Area of Science:

• Cardiovascular Surgery
• Cardioplegia Solutions
• Myocardial Protection

Background:

• The original Del Nido cardioplegia (DN) solution is not universally available due to reliance on PlasmaLyte, which lacks approval in some regions.
• Developing an accessible and effective alternative cardioplegia solution is crucial for global cardiac surgical practice.
• This study investigates a modified DN solution based on normal saline (NS) as a potential substitute.

Purpose of the Study:

• To evaluate the safety and effectiveness of a modified normal saline-based Del Nido cardioplegia (NS-DN) solution.
• To compare the myocardial protective qualities of NS-DN against the original DN formulation.
• To assess left ventricular (LV) function recovery and myocardial integrity after global ischemia.

Main Methods:

• A modified DN solution was prepared using normal saline (NS), distilled water, KCl, NaHCO3, MgSO4, lidocaine, and mannitol.
• Fourteen piglets underwent 90 minutes of global ischemia during cardiopulmonary bypass, receiving either original DN or the NS-based DN.
• Left ventricular (LV) systolic (end-systolic elastance, EES) and diastolic (end-diastolic pressure-volume relationship, EDPVR) functions were assessed using a conductance catheter. Creatine kinase-MB (CK-MB) and mitochondrial scores were also analyzed.

Main Results:

• Left ventricular contractility recovery (%EES) was comparable between the original DN (89.3 ± 20.6%) and NS-DN (99.3 ± 18.4%) groups.
• Left ventricular compliance recovery (%EDPVR) showed no significant difference between the groups (102.7 ± 28.2% vs 94.4 ± 22.8%).
• Creatine kinase-MB levels and mitochondrial scores were similar between groups, indicating no increased myocardial damage with NS-DN.

Conclusions:

• The normal saline-based modified Del Nido cardioplegia (NS-DN) solution effectively preserves left ventricular function after prolonged global ischemia.
• NS-DN demonstrates comparable safety and efficacy to the original Del Nido cardioplegia.
• This modified NS-based DN solution can be safely substituted for the original formulation, enhancing accessibility in cardiac surgery.