The effect of transplant center volume on survival after heart transplantation: A multicenter study
Received 12 March 2009; received in revised form 14 September 2009; accepted 16 November 2009. published online 08 February 2010. Corrected Proof
Objective
Few studies have examined the association between procedural volume and clinical outcomes in heart transplantation. This retrospective study was performed on a contemporary cohort of heart transplant recipients to better elucidate the effect of transplant center volume on 1-year mortality.
Methods
Data from the Scientific Registry of Transplant Recipients were used to analyze the relationship between transplant center volume and short-term survival. Center volume designation (very low, low, medium, and high) was assigned on the basis of quartiles with approximately equal numbers of patients per group. Survival differences were explored using Cox proportional hazards modeling to adjust for differences in variables between volume groups and to determine variables associated with 1-year mortality.
Results
Between January 1, 1999, and May 31, 2005, 13,230 heart transplantations were performed at 147 transplant centers in the United States. Although most recipient and donor characteristics were similar across quartiles, larger volume centers were more likely to perform transplantations in older candidates and accept organs from older donors with longer cold ischemia times. A statistically significant relationship between transplant center volume and 1-year mortality was observed. Compared with the reference group (very low volume), the hazard ratios for the low, medium, and high-volume quartiles were 0.71, 0.64, and 0.56, respectively (P < .001 for each group compared with the reference).
Conclusion
There was a significant association between transplant center volume and 1-year survival. Patients who undergo cardiac transplantation at very low-volume centers are at higher risk for early mortality than those who undergo transplantation in higher-volume centers.
cDivision of Cardiovascular Medicine, University of Michigan Health System, Ann Arbor, Mich
Address for reprints: Jeffrey H. Shuhaiber, MD, Cincinnati Children's Hospital, 3333 Burnett Ave, MLC 2004, Cincinnati, OH 45229.
Disclosures: None.
The Scientific Registry of Transplant Recipients is funded by contract number 234-2005-37009C from the Health Resources and Services Administration, US Department of Health and Human Services. The views expressed herein are those of the authors and not necessarily those of the US Government.
Author responsible for data analyses: Jeff Moore, MS