10 Years’ Experience after ABO-Incompatible Heart Transplantation in Infants: “single center experience”

Objectives: ABO-incompatible heart transplantation (HTx_i) may reduce waiting time by extending organ availability. The aim of this study was to evaluate mid- and long-term results after ABO HTx_i at our institution.

Methods: Data of seven patients (pts; m/f 4/3) younger than 17 months at the time of HTx_i between 2004 and 2017 were examined for this retrospective follow-up study. Primary outcome was survival after HTx_i. The following parameters were evaluated: renal- and cardiac function, incidence of acute or chronic rejection, cytomegalic virus (CMV) infection, transplant vasculopathy, and posttransplant lymphoproliferative disease (PTLD).

Results: Median follow-up was 8.8 years (1–13). Five pts presented with dilated cardiomyopathy and two with hypoplastic left heart syndrome. Preoperative mechanical support was required in three pts. Median waiting time was 1.1 months (0.1–6.2). Gender of donor/recipient was: three pts m/m, one m/f, one f/m, and two f/f. Blood group of donor/recipient was: two pts A/0, three B/0, one AB/0, and one B/A. CMV status of donor/recipient was one pt +/+, one −/+, and five −/−. Postoperative mechanical support was required in two pts. Immunosuppressive therapy was started using tacrolimus, mycophenolate (MMF), and steroids in all pts. Induction was either antithymocyte globulin or basiliximab in all pts.

Transplant-free survival at 30 days, 1, and 10 years was 100, 86, and 67%, respectively. Re-HTx combined with renal transplantation was necessary in one pt 5.8 years posttransplant.

Four pts suffered from signs of acute rejections. Left ventricular function was reported as normal at last visit in all pts. Arterial hypertension occurred in four pts and graft vasculopathy could be observed in five pts: one pt Stanford I, two pts Standford II, and two pts without documented graft vasculopathy. Renal impairment was noted in five pts. No development of diabetes mellitus was observed, whereas three pts developed a posttransplant tumor, two pts PTLD, and one pt bladder carcinoma.

Conclusion: Acute rejections and an impaired renal function are frequent following HTx_i. Nonetheless, mid- and long-term results show that ABO HTx_i is an acceptable therapeutic option for infants with end-stage congenital or acquired heart disease.