Continuous retrograde cardiac perfusion decreases risk of reoperative coronary artery bypass grafting.

Abstract

Embolization of atheromatous debris from old saphenous vein grafts is a major factor that increases the risk of reoperative coronary artery bypass grafting (CABG) when compared with primary CABG. To decrease this risk, a technique consisting of minimal dissection of the heart prior to cross clamping, continuous retrograde coronary sinus perfusion with 32 degrees C blood, and temporary posterior cardiac interventricular vein occlusion, during which time all dissection and anastomoses are performed, was evaluated prospectively in 130 consecutive patients from January 2, 1991, through February 28, 1995. This group was compared with a cohort of 1107 patients undergoing primary CABG performed concurrently. The two groups were similar in age (median sixty-eight years), incidence of hypercholesterolemia, peripheral vascular disease, smoking history, and left main stem stenosis. More patients undergoing reoperative CABG had previous myocardial infarctions (61.5% vs 54.5%), a higher incidence of triple-vessel coronary artery disease (89.2% vs 77.1%, P = 0.002), and a lower ejection fraction (54.0% vs 56.9%). The median interval from primary CABG to reoperative CABG was one hundred twenty-seven months with a range of 2.5 to two hundred seventy-nine months. The cross clamp time (median one hundred three vs sixty-nine minutes, P = 0.000001) and perfusion time (median one hundred thirty-four vs ninety-four minutes, P = 0.000001) were significantly higher in the reoperative CABG group. The requirements for inotropic support postoperatively, perioperative myocardial infarction (1.5% vs 2.4%, P = 0.397), and mortality (3.1% vs 3.4%, P = 0.54) were statistically equivalent in the two groups. These data reveal that continuous retrograde coronary sinus perfusion, posterior cardiac interventricular vein occlusion, and single cross-clamping technique improve outcomes of reoperative CABG to that approaching primary CABG.