Objective: Most studies of anastomotic technique have been underpowered to detect subtle differences in survival. We analyzed the United Network for Organ Sharing database for trends in use and outcomes after either bicaval or traditional (biatrial) anastomoses for heart implantation. Methods: Review of United Network for Organ Sharing data identified 20,999 recipients of heart transplants from 1997 to 2007. Patients were stratified based on the technique of atrial anastomosis: standard biatrial (atrial group, n = 11,919, 59.3%), bicaval (caval group, n = 7661, 38.1%), or total orthotopic (total group, n = 519, 2.6%). Results: The use of the bicaval anastomosis is increasing, but many transplantations continue to use a biatrial anastomosis (1997, 0.2% vs 97.6%; 2007, 62.0% vs 34.7%; P < .0001). Atrial group patients required permanent pacemaker implantation more often (odds ratio, 2.6; 95% confidence interval, 2.2-3.1). Caval group patients had a significant advantage in 30-day mortality (odds ratio, 0.83; 95% confidence interval, 0.75-0.93), and Cox regression analysis confirmed the decreased long-term survival in the atrial group (hazard ratio, 1.11; 95% confidence interval, 1.04-1.19). Conclusions: Heart transplantations performed with bicaval anastomoses require postoperative permanent pacemaker implantation at lower frequency and have a small but significant survival advantage compared with biatrial anastomoses. We recommend that except where technical considerations require a biatrial technique, bicaval anastomoses should be performed for heart transplantation. © 2010 by The American Association for Thoracic Surgery.