Mortality Is Increased in Pediatric Heart Transplant Recipients with a Positive Cross-Match

Utilization of positive (+) cross-match (XM) hearts is tempting when shortages of pediatric donor hearts exist, especially for patients with high pre-transplant panel reactive antibodies (PRA), for whom a negative (-) XM organ may be difficult to find. In light of recent literature advocating the use of +XM organs, we sought to define our single center outcomes of heart transplant (HTx) recipients of a +XM organ to better delineate the safety of this practice, to guide donor selection, and ultimately, to help determine treatment of this subset of patients who receive a +XM donor heart. We retrospectively reviewed the electronic medical records of patients who received a HTx at our institution from January 2007 to August 2014. P values were calculated by Chi Square, Fisher’s exact test, or t-test as appropriate. 117 patients received a HTx during the specified period, of which 12 (10%) had a +XM. All +XM patients were flow positive and three (31 %) were also B and T cell CDC positive. The mean peak PRA in the year preceding transplant was 14% class I and 8% class II for the -XM group and 46% and 64% for the +XM group (p= 0.002 and <0.001, respectively). Mortality at 1-year post-HTx for the -XM group was 5.1% vs 33.3% for the +XM group, p<0.001. The mortality rate for the three CDC positive patients was 66.7%. Mortality at 3-years post-HTx for those with an adequate follow-up time was 10% for -XM patients and 45% for +XM patients, p=0.002. The rate of rejection requiring treatment was 21% at 90 days and 30% at 1 year for the -XM patients, compared to 58% at 90 days and 58% at 1 year for the +XM group, P=0.004 and 0.05 respectively. +XM patients were given induction (antithymocyte globulin or Basiliximab) more often than -XM patients (p<0.001). Patients with higher PRAs in the year preceding HTx are more likely to have a +XM. Patients with a +XM HTx had a significantly higher rate of rejection at 90 days and at 1 year. Patients with a +XM had a markedly increased risk of dying one and three years post-transplant. The increase in rejection in the +XM cohort likely explains the increased mortality in this group. The results of our single center experience indicate that heightened vigilance is needed for those patients who receive a +XM organ. Additional investigation is warranted to evaluate alternative treatment strategies for these high-risk patients.