BACKGROUND Long-term results of aortic root replacements and the factors affecting long-term mortality were analyzed. METHODS We operated on 254 patients from June 1993 to November 2008 for aortic root replacement with Bentall de Bono procedure. Two hundred five patients were male (80.7%) and 49 patients (19.3%) were female. The mean age was 48.3 +/- 14.7 years (range, 14 to 78 years). We performed 72 concomitant procedures in 69 patients, and the most commonly performed procedure was coronary artery bypass grafting in 37 patients (14.6%). The most common indication for aortic root replacement was aneurysm in 235 patients (92.5%). Thirty-four patients (13.4%) had Marfan syndrome. Hypothermic circulatory arrest was used in 52 patients (20.5%). After removing the clamp, we had to reclamp the aorta in 26 patients (10.2%) undergoing operation. RESULTS Postoperatively 30 patients (11.8%) had in-hospital mortality. The late mortality was 2.8% (7 patients). The most common reason for hospital mortality was low cardiac output (18 in 30 patients; 51.4%). Neurologic complications were seen in 16 patients (6.3%). The mean duration of hospital stay was 16.6 +/- 11.3 days (range, 5 to 77 days). Postoperative follow-up was 6.3 +/- 4.5 years (range, 0 to 15.5 years) on average. Late mortality was significantly affected by Marfan syndrome (p = 0.025) and reclamping the aorta (p = 0.036). Actuarial survival for the overall 254 patients is 88.4% +/- 2.1%, 87.4% +/- 2.2%, and 84.5% +/- 2.56% at 1, 3, and 10 years, respectively. CONCLUSIONS The late-term results of aortic root replacement with the modified Bentall de Bono procedure are satisfactory. Survival is decreased in patients with Marfan syndrome and in the patients who had reclamping intraoperatively.