Perioperative outcomes of cardiac surgery in kidney and kidney-pancreas transplant recipients

Objective: Cardiovascular disease is a common cause of morbidity and mortality in organ transplant recipients, and cardiac surgery has become more common in this population. We performed a retrospective study of kidney transplant recipients who underwent cardiac surgery over the past 10 years at our institution with an emphasis on evaluating postoperative outcomes. Methods: Seventy-four patients with previous abdominal transplants underwent cardiac surgery (93% coronary artery bypass grafting, 5.4% bypass grafting plus valve, and 1.4% valve) between 1995 and 2005. These recipients were compared with 895 adult nontransplant patients undergoing cardiac surgery between 2000 and 2005. Only kidney and kidney-pancreas recipients were included in the analysis (n = 70) because there were only 2 liver and pancreas alone transplants. Results: As compared with nontransplant patients, kidney transplant patients were younger (mean age 52.1 ± 10 years vs 61 ± 13 years; P < .001) and had an increased incidence of diabetes (92.9% vs 39.1%; P < .001), peripheral vascular disease (37.1% vs 19.1%; P < .001), chronic kidney insufficiency (73.0% vs 13.4%; P < 0.001), and unstable angina (44.8% vs 25.7%; P = .005) There was no difference between the two groups in the complication rate at 30 days after surgery, except that transplant patients were more likely to have postoperative kidney dysfunction (32.6% vs 6.1%; P < .001) and require hemodialysis (11.7% vs 1.1%; P < .0001). Thirty-day postoperative mortality was similar between groups (1.4% vs 2.9%; P = not significant). By multivariable analysis, preoperative congestive heart failure, nonelective surgery, prolonged cardiopulmonary bypass times, peripheral vascular disease, and lower creatinine clearance were significant risk factors for postoperative mortality; however, prior kidney transplant was not an independent risk factor for 30-day postoperative mortality. Conclusions: Despite their increased incidence of comorbid conditions, the postoperative outcomes of cardiac surgery in kidney transplant recipients are similar to those in the nontransplant population except for a higher incidence of kidney dysfunction in transplant patients.