Del nido versus conventional blood cardioplegia in patients with obstructive hypertrophic cardiomyopathy.

Background: Myocardial protection is essential in cardiac surgery with cardiopulmonary bypass The Del Nido cardioplegia which was initially used in pediatric cardiac surgery, has been increasingly used in adult cardiac surgery recently. However, no literature has reported the efficacy of DNC in hypertrophic obstructive cardiomyopathy.

Methods: This retrospective study involved elective patients who underwent extended surgical myectomy with or without concomitant cardiac surgical procedures between September 2017 and June 2022. Patients were distributed into two groups, the DNC and the CBC group. The primary outcome was high-sensitivity cardiac troponin I (hs-TnI) and creatine kinase-MB (CK-MB) levels at the 0, 1, and 2 postoperative days. The secondary outcomes contained: intraoperative LVEF, return to spontaneous rhythm; postoperative myocardial infarction, worsening or deteriorating of EF, mechanical circulatory support; new-onset atrial fibrillation; mechanical ventilation duration; intensive care unit hours; in-hospital days.

Results: Fifty-nine patients were included and divided into the CBC (n = 15) and the DNC group (n = 44). There was no statistical difference in patients' demographics and preoperative parameters between the two groups. No in-hospital mortality. The total cardioplegia volume [21.93(18.36,26.07) vs. 25.68(23.17,37.12), p = 0.012] and infusion times [1(1,1) vs. 2(2,3), p = 0.000] were less and the incidence of return to spontaneous rhythm after declamping was higher in the DNC group [97.7% vs. 73.3%, p = 0.013]. Postoperative hs-TnI and CK-MB levels were comparable between the two groups. A longer DNC infusion interval was associated with higher levels of CK-MB on postoperative day 1 and day 2 (p = 0.009 and p = 0.011, respectively).

Conclusions: The use of DNC in extended surgical myectomy procedure was as safe and effective as CBC. However, DNC infusion interval over 60 minutes was associated with increased postoperative CK-MB levels.