Objective: Antegrade and retrograde infusions of cardioplegia may provide more homogenous distribution of cardioplegia especially in cases of coronary arteries occlusion. The purpose of this study was to compare intermittent ante grade- retrograde and ante grade cardioplegia on myocardial function following CABG.
Methods: One hundred ninety six patients in two groups were studied on a non randomized basis in order to compare their operational results after using the two methods. In the antegrade-retrograde method (group A), 15 ml/kg of cold blood infusion of antegrade cardioplegia was followed by 8 ml/kg of retrograde infusion. The antegrade-retrograde route of infusion was repeated every 20 minutes (IO ml/kg and 8 ml/kg respectively). In the antegrade group (group B), 15 ml/kg of cold blood cardioplegia was followed by 10 ml/kg in repeated doses every 20 minutes. Important variables of myocardial performance were compared in the two groups.
Results: The two groups had similar preoperative characteristics (age, sex, body mass index, severity of coronary artery disease and ejection fraction). Postoperative ejection fraction either did not change or increased 5 to 15% in 51.1% of group A. Inotropic agent was needed in 8.2% of this group, while post operative ejection fraction reduced 5 to 20% in 76.9% of group B and inotropic agent was needed in 24.5% of this group (P<0.001 and P<0.002 respectively). The mortality rate was more in the control group, but was not statistically significant. The ventilatory support time was longer in the control group (P<0.01).
Conclusion: In view of our findings, we conclude that there is a significantly better postoperative myocardial performance following antegrade-retrograde cardioplegia and we recommend it as a routine method for myocardial protection in coronary artery bypass graft.