Abstract 4370120: Comparative Analysis of Clinical Outcomes Following Transcatheter Aortic Valve Replacement in Patients with Wild-Type Transthyretin Amyloidosis: A Multicenter TriNetX Study

Abstract

Background: Wild-type transthyretin amyloidosis (ATTR) is an underrecognized contributor to aortic stenosis, and its presence may influence procedural outcomes after transcatheter aortic valve replacement (TAVR). However, real-world outcomes of TAVR in this population remain poorly defined. This study aimed to evaluate clinical outcomes—specifically mortality, heart failure hospitalizations, and stroke—in patients with wild-type ATTR amyloidosis undergoing TAVR, excluding those with prior surgical aortic valve replacement (SAVR). Methods: This retrospective cohort study utilized TriNetX, a federated health research network capturing data from 66 U.S. healthcare organizations. Adult patients diagnosed with wild-type ATTR amyloidosis (ICD-10: E85.82) who underwent TAVR were included; patients with prior SAVR were excluded. Outcomes assessed included all-cause mortality, heart failure hospitalizations, ischemic stroke, and hemorrhagic stroke, evaluated up to 5 years post-procedure. Statistical analyses included risk proportions and 95% confidence intervals (CIs). Kaplan-Meier survival analysis was used for event-free survival estimates. A p-value <0.05 was considered statistically significant. Results: A total of 126 patients were included. All-cause mortality occurred in 25.4% (n=32) of patients during follow-up. Heart failure hospitalizations were highly prevalent, occurring in 85.7% (n=108). Ischemic stroke occurred in 11.1% (n=14), while hemorrhagic stroke was reported in 7.9% (n=10). Kaplan-Meier survival probabilities at the end of follow-up were 27.1% for mortality, 7.0% for heart failure hospitalization, 74.0% for ischemic stroke, and 94.5% for hemorrhagic stroke. Conclusions: In this large, real-world cohort of patients with wild-type ATTR amyloidosis undergoing TAVR, heart failure hospitalizations emerged as the most frequent adverse outcome, with over 85% of patients experiencing at least one hospitalization. Mortality also remained high, reflecting the complex disease burden in this population. Stroke events were less frequent but remain clinically relevant. These findings underscore the importance of aggressive heart failure management and comprehensive post-procedural care in patients with ATTR amyloidosis undergoing TAVR. Further studies are warranted to identify optimal management strategies and to refine patient selection criteria to improve outcomes in this challenging patient population.