Combined antegrade/retrograde cardioplegia for myocardial protection: A clinical trial

Abstract

The role of retrograde coronary sinus perfusion in the preservation of ischemic myocardium is controversial. We evaluated the use of combined antegrade and retrograde cardioplegia in 59 patients undergoing coronary artery bypass surgery. Nineteen patients were administered antegrade cardioplegia, whereas 40 patients were administered antegrade plus retrograde cardioplegia. Hemodynamic data were obtained before the onset of cardiopulmonary bypass and at 1, 2, 4, 8, 16, and 24 hours after cessation of cardiopulmonary bypass. Myocardial function was assessed by measuring systemic blood pressure, heart rate, cardiac index, pulmonary artery pressure, and capillary wedge pressure. Both cohorts were similar in age, incidence of hypertension, diabetes, and previous myocardial infarction. No significant differences were noted in the need for postoperative inotropic support, the incidence of postoperative arrhythmias, myocardial infarction, heart block, or death. The two groups were similar with respect to cardiac index and systemic and pulmonary vascular resistance. However, the left ventricular stroke work index, when expressed as a function of its prebypass control value, was significantly improved (p less than 0.01) in the cohort administered combined cardioplegia. In the combined group recovery of left ventricular stroke work index occurred earlier and was more complete. These results suggest that the use of combined antegrade/retrograde cardioplegia is safe and may provide superior protection.