Antegrade crystalloid cardioplegia vs antegrade/retrograde cold and tepid blood cardioplegia in CABG

Background. This study evaluated the myocardial protective strategies in isolated coronary bypass surgeries. Methods. One hundred and twenty-eight patients were prospectively randomized to 3 techniques of myocardial protection; group I (n = 47) antegrade/retrograde tepid blood cardioplegia, group II (n = 40) antegrade/retrograde cold blood cardioplegia with topical cooling, group III (n = 41) antegrade crystalloid cardioplegia with topical cooling. Results. The incidence of spontaneous defibrillation was significantly higher in group I (p <0.001) while the incidence of low cardiac output was not different between the 3 groups. The incidence of ventricular arrhythmia was higher in group III (p <0.016 group III vs I). There was no significant statistical difference in hemodynamic recovery between the 3 groups. CK-MB levels were significantly lower in group I versus the other 2 groups, (p= 0.0013, 0.04). Acid release and oxygen extraction were higher in group II than in group I (p= 0.06) during cardioplegia and reperfusion. Lactate release was less in group I at the release of aortic cross-clamp, and reperfusion. There was no significant difference between the 3 groups in ICU stay, ventilation time, or hospital complications. Conclusions. Tepid blood cardioplegia showed superiority in metabolic and functional recovery, whereas crystalloid cardioplegia had the highest incidence of postoperative arrhythmias. There was no significant statistical difference between the 3 groups in hospital mortality and morbidity.