The UNOS experience on heart transplantation for amyloid cardiomyopathy

Background Previous evidence suggests that heart transplantation in patients with amyloid cardiomyopathy (ACM) may be suboptimal given the risk of amyloid recurrence. Herein, we sought to investigate the most current data on a nationwide scale. Methods We performed a retrospective analysis of the United Network for Organ sharing (UNOS) registry for adult patients who underwent heart transplantation (01/2001-12/2022) for ACM compared to idiopathic dilated cardiomyopathy (DCM), ischemic cardiomyopathy (ICM), idiopathic restrictive cardiomyopathy (RCM) and cardiomyopathy associated with congenital heart disease (CHD). A propensity score matched analysis was also performed for patient characteristics that were significantly different at baseline between ACM and DCM. Results A total of 21,457 patients were included in our analysis. A significant increase in the number of patients undergoing transplant for ACM was observed over time (100% increase in 2020 compared to 2010; p<0.001)(Figure 1A). Unadjusted and overall mortality did not differ among groups (Figure 1B). Baseline characteristics differed between ACM and DCM groups in terms of age, gender, race, diabetes mellitus, body mass index, smoking, malignancy, implantable cardiac defibrillator, inotropes at listing, creatinine, cardiac output and being on extracorporeal membrane oxygenator at the time of transplant. In the propensity matched cohorts, five-year mortality was similar between groups (HR: 1.10; 95% CI: 0.66, 1.83; p=0.703). Logistic regression showed that the ACM had lower incidence of postoperative stroke (OR: 0.26; 95% CI: 0.07, 0.09; p=0.044), while no difference was noted in the need for pacemaker implantation (p=1.000) or dialysis (p=0.189). Conclusions There has been an increase in the number of patients undergoing heart transplant for ACM. Unadjusted and propensity score matched analysis showed that there was no difference in survival when compared to DCM patients. Carefully screened ACM patients may be benefited from heart transplant, yet further studies are warranted.1A 1B