Background: The purpose of this study was to compare posttransplantation morbidity and mortality in orthotopic heart transplant recipients bridged to transplant with a left ventricular assist device with nonbridged recipients. To account for potential differences across device types, we stratified bridge-to-transplant recipients by type of ventricular assist device: extracorporeal (EXTRA), paracorporeal (PARA), and intracorporeal (INTRA).
Methods: The United Network for Organ Sharing provided de-identified patient-level data. The study population included 10,668 orthotopic heart transplant recipients aged 18 years old or older and undergoing transplantation between January 1, 2001, and December 31, 2006. Follow-up data were provided through August 3, 2008, with a mean follow-up time of 3.17 +/- 2.15 years (range, 0-8.11 years). The primary outcome was actuarial posttransplant graft survival. Other outcomes of interest included infection, stroke, and dialysis during the transplant hospitalization; primary graft failure at 30 days; transplant hospitalization length of stay; and long-term complications including diabetes mellitus, transplant coronary artery disease, and chronic dialysis. Multivariable Cox proportional hazards regression (backward, P < .15) was used to determine the relationship between groups and overall graft survival, and multivariable logistic regression analysis (backward, P < .15) was used to determine the relationship between groups and secondary outcome measures.
Results: In multivariable Cox regression analysis, when compared with the nonbridged group, risk-adjusted greater than 90-day graft survival was diminished among the EXTRA group (hazard ratio = 3.54, 2.28-5.51, P < .001), but not the INTRA group (1.04, 0.719-1.51, P = .834) or the PARA group (1.06, 0.642-1.76, P = .809). There were no significant differences in risk-adjusted graft survival across the 4 groups during the 90-days to 1-year or 1- to 5-year intervals. However, at more than 5 years, risk-adjusted graft survival in the INTRA group (0.389, 0.205-0.738, P = .004) was better than in the nonbridged group. The EXTRA, PARA, and INTRA groups all experienced increased risks of infection. The EXTRA group had increased risks of dialysis, stroke, and primary graft failure at 30 days, whereas neither the PARA nor the INTRA group differed from the nonbridged group. Long-term complications did not differ by group.
Conclusion: The use of implantable left ventricular assist devices as bridges to transplantation, including both intracorporeal and paracorporeal devices, is not associated with diminished posttransplant survival. However, 90-day survival was diminished in recipients bridged with extracorporeal devices.