Clinical Outcomes of Aortic Stenosis in Amyloidosis: A United States National Cohort Study.

Background: Literature regarding outcomes associated with surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) among amyloidosis (AM) with aortic stenosis (AS) is limited.

Objectives: We aim to study the mortality and in-hospital clinical outcomes among AM with AS associated with SAVR or TAVR.

Methods: We performed a retrospective study of all hospitalisation encounters associated with a diagnosis of AM with AS, using the Nationwide Readmissions Database for the years 2012-2019. Primary outcomes were in-hospital mortality, and 30-day readmissions.

Results: A total of 4,820 index hospitalisations of AS (mean age 78.35±10.11 years; female 37.76%) among AM were reported. Total 464 patients had mechanical intervention, 251 patients (54.1%) TAVR and 213 patients (45.9%) SAVR. A total of 317 patients (6.77%) with AS died; TAVR 4.4%, SAVR 11.9% (p=0.01) and 6.66% died among the subgroup who did not have any mechanical intervention. Higher complication rates were observed among patients who had SAVR than those who had TAVR including acute kidney injury (39.8% vs 22.4%; p=0.01), septic shock (12.1% vs 4.4%; p=0.05) and cardiogenic shock (22% vs 4.4%; p<0.001). Acute heart failure was higher among patients who had TAVR (40.2% vs 27.5%; p=0.04) than those who had SAVR. All conduction block and ischaemic stroke were similar between the two groups (p=0.09 and p=0.1). The overall 30-day readmission rate among AM with AS encounters was 16.82%, higher among TAVR compared to SAVR subgroups (21.25% vs 11.17%; p=0.001).

Conclusions: Among AM with AS hospitalisations, TAVR had mortality benefits compared to SAVR and non-mechanical intervention subgroups. Moreover, higher 30-day mortality rate were observed among SAVR subgroup, which may suggest that TAVR should be strongly considered in AM patients complicated by AS.