Waitlist Mortality of Patients With Amyloid Cardiomyopathy who Are Listed for Heart Transplantation and Implications for Organ Allocation

Background: Outcomes of patients with amyloid cardiomyopathy (ACM) undergoing heart transplantation have been reported, but there are scant data concerning the waitlist mortality (WLM) of these patients. Aim: The aim of this study was to investigate whether patients with ACM have higher waitlist mortality compared to those with other types of cardiomyopathies. Methods: We queried the United Network for Organ Sharing registry for all patients (age ≥ 18 years) listed for heart transplantation between 2008 and 2015. We compared patients with ACM to those with dilated cardiomyopathy (DCM) or idiopathic restrictive cardiomyopathy (RCM) for WLM and waitlist mortality or delisting for deterioration (WLM/D). We identified 306 patients with ACM, 183 with RCM and 8416 with DCM. Patients with ACM were older (ACM 61 vs RCM 49 vs DCM 51 years, P < .001), were more likely to be male (82% vs 60% vs 73%, P < .001) but less likely to be listed as status 1A (16% vs 18% vs 23%, P < .001). After adjusting for baseline characteristics, ACM was associated with increased risk of mortality and mortality/delisting compared with DCM (HR 2.03 [1.36–3.04], P = .001 for WLM; HR 2.07 [1.55–2.78], P < .001 for WLM/D) but not with other RCMs (HR 1.28 [0.54–3.02], P = .58 for WLM; HR 0.97 [0.56–1.69], P = .91 for WLM/D). Results: Patients with ACM are listed with lower acuity and have higher waitlist mortality compared with those with dilated cardiomyopathies. Further studies are needed to identify whether special prioritization should be considered for patients with ACM listed for heart transplantation.