Outcomes of simultaneous heart-kidney transplant in the US: a retrospective analysis using OPTN/UNOS data

Simultaneous heart-kidney transplantation (SHK) remains uncommon in the US. We examined outcomes of SHK compared to heart transplant alone (HTA) and deceased donor kidney transplant (DDKT). Data from OPTN/UNOS heart and kidney data bases were used to identify 16,710 HTA, 263 SHK transplants and 68,833 DDK transplants between 1998 and 2007. Outcomes included patient survival (PS), acute cardiac and renal rejection and renal graft survival (rGS). The adjusted risk of death was 44% lower with SHK compared to HTA. Over half of SHK were performed in cases where pretransplant dialysis was not initiated. In these cases, there was no significant difference in the risk of death between SHK and HTA (HR 1.01; 95% CI 0.67-1.50). Recipients of SHK had worse 1-year rGS and PS and had a higher relative risk of overall renal graft loss compared to DDKT recipients. One-year rates of cardiac (14.5%) and renal (6.5%) rejection were lower in SHK compared to HTA and DDKT, respectively. Recipients of SHK had a lower adjusted risk of death compared to HTA recipients, particularly in patients who required pretransplant dialysis. These data suggest that SHK should be considered in heart transplant candidates with renal failure requiring dialysis, whereas the utility of SHK in cases of renal failure not requiring dialysis warrants further study.