Comparison of Antegrade Cold Blood and Crystalloid Cold Cardioplegia for Repair of Tetralogy of Fallot in Pediatric Heart Surgery: A Randomized Controlled Trial

Background: Many small-sized trials have evaluated the effectiveness of cold blood cardioplegia (CBC) compared with crystalloid cold cardioplegia (CCC) for myocardial protection during pediatric cardiac surgery. We hypothesized that CBC might preserve the myocardium more effectively than St. Thomas’ crystalloid cardioplegia in pediatric cardiac surgery and, thus, investigated the efficacy of CCC versus CBC in terms of myocardial metabolism protection in patients undergoing the corrective repair of Tetralogy of Fallot (TOF). Methods: Thirty pediatric patients with TOF were randomly allocated to either CBC (n=15, 4:1 dilution, potassium chloride 15 mEq/L) or CCC (4 °C, n=15). Arterial and coronary sinus blood samples were analyzed for lactate and oxygen contents. Results: The patients were demographically similar in both groups. The lactate concentration in coronary sinus blood was not significantly different between the two groups exactly after cardiopulmonary bypass (2.5±1.3 vs. 2.5±1.0 mmol/L; p value = 0.9) but coronary sinus blood O2 saturation was higher early after cardiopulmonary bypass in the CBC group (59.0±18.5 vs. 44.0±17.6 meq; p value = 0.03). Conclusion: Our results showed no significant clinical advantages of antegrade CBC over CCC during hypothermic cardioplegic arrest in pediatric cardiac surgery.