Durable Mechanical Circulatory Support in Patients with Amyloid Cardiomyopathy: Insights from INTERMACS

Background: Many patients with amyloid cardiomyopathy (ACM) develop advanced heart failure, and durable mechanical circulatory support (MCS) may be a consideration. However, data describing clinical outcomes after MCS in this population is limited.

Methods: Adult patients in the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) with dilated cardiomyopathy (DCM, n=19,921), non-amyloid restrictive cardiomyopathy (RCM, n=248), or ACM (n=46) between 2005 and 2017 were included. Patient and device characteristics were compared between cardiomyopathy groups. The primary endpoint was the cumulative incidence of death with heart transplantation as a competing risk.

Results: Patients with ACM (n=46) were older (61 years [IQR 55-69 years] versus 58 years [IQR 49-66 years] for DCM and 55 years [IQR 46-62 years] for non-amyloid RCM, p<0.001) and INTERMACS profile 1 (30.4% versus 17.9% for DCM and 21.0% for non-amyloid RCM, p=0.04) at device implantation. Use of biventricular support (biventricular assist device or total artificial heart) was highest for ACM patients (41.3% versus 6.7% and 19.4% for DCM and non-amyloid RCM patients, respectively, p=0.014). The cumulative incidence of death was highest for patients with ACM than with DCM or non-amyloid RCM (p<0.001) but did not differ significantly between groups for those who required biventricular MCS.

Conclusions: Compared to DCM or non-amyloid RCM patients who received durable MCS, those with ACM experienced the highest use of biventricular support and the worst survival. These data highlight concerns with the use of durable MCS for ACM patients.