Comparison of Del Nido and Blood Cardioplegia in Pediatric Patients Undergoing Surgical Repair for Congenital Heart Disease

Revisiting risk factors and incidence of postoperative tachyarrhythmias in pediatric cardiac surgery

Postoperative tachyarrhythmias are a significant complication following pediatric congenital heart surgery. This study revisits the incidence and risk factors for postoperative tachyarrhythmias, focusing on congenital heart disease with a higher propensity for arrhythmias. We aim to determine if surgical and perioperative improvements have mitigated these risks. The findings may inform clinical practices and guide the development of preventive strategies. This retrospective cohort study was conducted at a tertiary university hospital, including pediatric patients under 18 years of age who underwent elective surgeries for ventricular septal defect (VSD) and/or right ventricular outflow tract (RVOT) obstruction variants between February 2018 and October 2021. Exclusion criteria included preexisting arrhythmias requiring treatment and intraoperative mortality. Data were collected from medical records. The primary outcome was the incidence and risk factors of postoperative tachyarrhythmias. Independent risk factors for these tachyarrhythmias were identified using multivariable logistic regression. Among the 385 patients included, with a median age of 24.8 months, 49 (12.7%) patients developed postoperative tachyarrhythmias, predominantly junctional ectopic tachycardia (JET; n = 46). The highest incidence was observed in patients with DORV with VSD (41.4%) and AVSD (26.7%). Independent risk factors included younger age, with each 6-month increase in age reducing the odds by 10% (adjusted OR 0.90, 95% CI 0.84-0.98, p = 0.009); prolonged CPB duration, with a 44% increase in odds per 30-minute increment (adjusted OR 1.44, 95% CI 1.20-1.73, p < 0.001); and the use of del Nido cardioplegia (adjusted OR 2.36, 95% CI 1.01-5.52, p = 0.047). Patients with postoperative tachyarrhythmias required significantly longer durations of mechanical ventilation, as well as extended intensive care unit and hospital stays. Postoperative tachyarrhythmias remain a significant concern in pediatric congenital heart surgery, especially in younger patients and those with complex heart defects. Strategies to reduce CPB duration and manage systemic hyperinflammation may lower the risk. Further research is needed to explore inflammatory processes in the development of these arrhythmias.

Mitochondrial respiratory pathways in immature rat heart tissue using different cardioplegic solutions

INTRODUCTION

Minor defects in the mitochondrial ATP-generating system and post-cardioplegia oxidative phosphorylation can negatively impact cardiac function in immature hearts. This study aimed to examine the mitochondrial respiratory pathway using three different cardioplegic solutions (Custodiol HTK, St. Thomas, and Del Nido) during moderate (1 h) and long (3 h) ischemic periods.

METHODS

A total of 41 male Wistar albino rats were utilized in this study. Five experiments were conducted without the use of any cardioplegic solution (CP0 group). To assess both moderate and prolonged ischemic periods, six experiments were carried out in each of the following groups: CP1 group (St. Thomas solution), CP2 group (Custodiol HTK solution), and CP3 group (Del Nido solution).

RESULTS

After 1 h, the highest mitochondrial respiration rate was observed in the CP3 group and the lowest in the CP1 group (p = 0.006). After adding ADP substrate, the highest mitochondrial ATP-production-coupled respiration was recorded in the CP3 group, which was similar to the control group CP0. After 3 h, while evaluating the ratio between mitochondrial respiration ATP-production coupled and basal respiration, significant differences were found between CP1 group and CP3 group (p = 0.035), as well as between the CP1 and CP0 groups (p = 0.045). Additionally, by assessing the condition of the outer mitochondrial membrane using the Cyt C effect (Cyt/Phos [ADP]), significant differences were observed between the CP1 and CP3 group (p = 0.004), as well as between CP1 and CP0 groups (p = 0.003).

CONCLUSION

Del Nido cardioplegic solution provided optimal mitochondrial protection under moderate and long myocardial ischemia conditions.

Del Nido cardioplegia versus cold blood cardioplegia in adult cardiac surgery: a meta-analysis of randomized clinical trials

OBJECTIVE

Systematic evaluation of the safety of del Nido cardioplegia compared to cold blood cardioplegia in adult cardiac surgery.

METHODS

We systematically searched PubMed, EMbase, The Cochrane Library and ClinicalTrials.gov for randomized clinical trials (published by 14 January 2024) comparing del Nido cardioplegia to cold blood cardioplegia in adult. Our main endpoints were myocardial injury markers and clinical outcomes. We assessed pooled data by use of a random-effects model or a fixed-effects model.

RESULTS

A total of 10 studies were identified, incorporating 889 patients who received del Nido cardioplegia and 907 patients who received cold blood cardioplegia. The meta-analysis results showed that compared with the cold blood cardioplegia, the del Nido cardioplegia had less volume of cardioplegia, higher rate of spontaneous rhythm recovery after cross clamp release, lower levels of postoperative cardiac troponin T and creatinine kinase-myocardial band, all of which were statistically significant. However, there was no statistically significant difference in postoperative troponin I and postoperative left ventricular ejection fraction. The clinical outcomes including mechanical ventilation time, intensive care unit stay time, hospital stay time, postoperative stroke, postoperative new-onset atrial fibrillation, postoperative heart failure requiring intra-aortic balloon pump mechanical circulation support, and in-hospital mortality of both are comparable.

CONCLUSION

Existing evidence suggests that del Nido cardioplegia reduced volume of cardioplegia administration and attempts of defibrillation. The superior postoperative results in CTnT and CK-MB may provide a direction for further research on improvement of the composition of cardioplegia.

Cardioplegia in Open Heart Surgery: Age Matters

INTRODUCTION

Cardioplegia is a pharmacological approach essential for the protection of the heart from ischemia-reperfusion (I-R) injury. Over the years, numerous cardioplegic solutions have been developed, with each cardioplegic approach having its advantages and disadvantages. Cardioplegic solutions can be divided into crystalloid and blood cardioplegic solutions, and an experienced surgeon chooses the type of solution based on the individual needs of patients in order to provide optimal heart protection. Importantly, the pediatric immature myocardium is structurally, physiologically, and metabolically different from the adult heart, and consequently its needs to achieve cardioplegic arrest strongly differ. Therefore, the present review aimed to provide a summary of the cardioplegic solutions available to pediatric patients with a special focus on emphasizing differences in heart injury after various cardioplegic solutions, the dosing strategies, and regimens.

MATERIAL AND METHODS

The PubMed database was searched using the terms cardioplegia, I-R, and pediatric population, and studies that investigated the influence of cardioplegic strategies on markers of cardiac muscle damage were further analyzed in this review.

CONCLUSIONS

A large body of evidence suggested more prominent benefits achieved with blood compared to those with crystalloid cardioplegia in pediatric myocardium preservation. However, standardized and uniform protocols have not been established so far, and an experienced surgeon chooses the type of cardioplegia solution based on the individual needs of patients, while the severity of myocardial damage strongly depends on the type and duration of the surgical procedure, overall patient condition, and presence of comorbidities, etc.