Comparison of two cardioplegia solution—del Nido solution and St. Thomas solution used in adult cardiac surgery

Abstract

Introduction: del Nido (DN) cardioplegia induces a depolarizing arrest during cardiac surgery. It is more dilute (1,4, blood crystalloid) as compared to the traditional 4:1 blood cardioplegia; it has lower Ca+2 and contains lidocaine. St. Thomas’ (ST) cardioplegia has been a popular crystalloid cardioplegia among cardiac surgeons; still, it must be administered constantly at short intervals during the surgery. Aim: To determine whether DN cardioplegia, with longer period of arrest provides better myocardial protection as compared to ST cardioplegia, with shorter period of arrest. Materials and Methods: The study population comprised 46 patients who undergone on pump coronary artery bypass grafting or any valve replacement surgery, which include aortic valve replacement, mitral valve replacement, and double valve replacement between February 2022 and June 2022. The patients were divided into two groups based on the type of cardioplegia given during surgery: (1) ST group (ST, n = 23) and (2) DN cardioplegia group (DN, n = 23). We compared the aortic cross clamp (CC) and cardiopulmonary bypass (CPB) times, number of doses required, and postoperative outcome in the two groups. Results: The CC of time of DN versus ST group (75.82 ± 27.24 vs 85.69 ± 37.20) min and bypass times of DN versus ST group (102.73 ± 35.28 vs 104.86 ± 38.9) min. The DN group was noticed to have shorter CC and CPB times with (P < 0.05). Fewer cardioplegia doses were required in the DN group versus the ST group (1.21 ± 0.42 vs 2.86 ± 1.28; P = 0.001), while a single cardioplegia dose was given to 18 DN patients (78.26%) versus 2 ST patients (8.69%) (P < 0.001). LVEF was better preserved in the DN group. Conclusions: The use of DN cardioplegia results in shorter CC and CPB times, reduces cardioplegia doses, and also provides better myocardial protection with a safety profile as compared to ST cardioplegia.