Heart Transplantation Outcomes in Radiation-Induced Restrictive Cardiomyopathy

BackgroundSome cancer therapies can cause advanced heart failure requiring heart transplantation. Although dilated cardiomyopathy is the most common phenotype, those who receive radiation may develop restrictive cardiomyopathy. The characteristics and transplantation outcomes patients with radiation-induced restrictive cardiomyopathy are not established.Methods and ResultsWe used United Network for Organ Sharing registry to identify adults who were listed for heart transplantation between 2000 and 2015 for radiation-induced restrictive cardiomyopathy (RT-RCM) and compared their characteristics and transplant outcomes to restrictive cardiomyopathies of other etiologies (RCM) and all other patients listed for heart transplantation (others). Of 45,041 adults, 87 (0.2%) of transplantations were due to RT-RCM, 1049 (2.3%) were due to RCM, and there were 44,805 others. Compared with patients with RCM and other etiologies, those with RT-RCM were younger, less likely male, more likely to be white, listed as status 2, and were also more likely to have had previous cardiac surgeries. Posttransplant, patients with RT-RCM had longer lengths of stay and higher early mortality; 1-, 3-, and 5-year cumulative survival were as follows for RT-RCM (76%, 66%, 58%), RCM (88%, 79%, 73%; P = .025 compared with RT-RCM), and other etiologies (88%, 82%, 76%; P = .012 compared with RT-RCM).ConclusionsPatients with end-stage RT-RCM are predominantly younger females with previous cardiac surgeries. Posttransplantation survival in these patients appears to be lower than in those with other forms of restrictive cardiomyopathies and heart failure etiologies, mainly because of higher early postoperative mortality. Further studies are needed to confirm these findings.