The purpose of these authors' study was to analyze their center's experience with orthotopic heart transplantation (OHT) and abdominal aortic aneurysms (AAA) with particular attention to corticosteroid dosing, hemodynamic parameters, and aneurysm growth rate. A retrospective review of all patients (453) who underwent OHT at their university-affiliated medical center over an 18-year period (1981-1999) was undertaken. Nine (2%) patients who developed AAAs were identified and aneurysm growth was correlated with corticosteroid immunosuppression and hemodynamic parameters. The mean age of OHT patients was 44.5 +/-15 years and the majority were males (371 males, 82%). Median follow-up was 5.7 years. Ischemic cardiomyopathy (IC) was the most common indication for transplantation (45.5% of patients). All AAA patients were male (p=0.157), with a mean age of 58.4 +/-4.8 years (p=0.001), and had undergone OHT for IC (p=0.001). Mean arterial blood pressure and ejection fraction in the AAA patients had increased from pretransplant values of 107 mm Hg and 14.3 +/-5.7% to 142 mm Hg (p=0.017) and 54.1 +/-14.1% (p<0.001), respectively, before aneurysm repair. Mean aneurysm diameter at the time of repair was 6.0 +/-0.8 cm, and the average growth rate was 1.2 +/-0.4 cm/year in the 4 patients in whom it could be measured. Aneurysm repair was performed urgently in 2 patients and electively in 7 patients with 1 early postoperative death (11%). The extent of corticosteroid immunosuppression, corticosteroid pulses, and total corticosteroid dosing did not correlate with the rate of aneurysm growth. Improved hemodynamics and progressive posttransplant hypertension may contribute to aneurysm formation and growth in this group of patients.