Heart Failure With Reduced Ejection Fraction: An Under-Appreciated Clinical Phenotype Of Transthyretin Cardiac Amyloid (ATTR-CA)

Abstract

<h3>Introduction</h3> Cardiac amyloidosis is an underrecognized infiltrative cardiomyopathy that is commonly reported to occur in the setting of heart failure with preserved ejection fraction (HFpEF), but a less-recognized presentation is heart failure with reduced ejection fraction (HFrEF).Hypothesis: We sought to determine the prevalence and clinical features of CA-TTR patients presenting with HFrEF (LVEF<=40%) phenotype and determine differences with HFpEF phenotype. <h3>Methods</h3> We retrospectively studied 200 patients with ATTR-CA. Differences between the two phenotypes were assessed using t-tests or Wilcoxon rank-sum (Mann-Whitney U) test/Kruskal-Wallis test for normally/non-normally distributed data, respectively. Survival analysis using Cox proportional hazard model was performed and survival distribution of both groups using Kaplan-Meier graph was plotted. <h3>Results</h3> Of the 200 patients, 82 patients (41%) had HFrEF. ATTR-CA with HFrEF were more often African American with the Val122Ile variant. Other clinically significant differences between the two groups included worse NYHA class, renal function and higher BNP in HFrEF group. 128 patients (64.5%) died during follow up and HFpEF patients had lower risk of death than HFrEF(HR 0.69 95, CI 0.49-0.98, p<0.05) <h3>Conclusion</h3> A significant percentage of patients with ATTR-CA present with HFrEF and not HFpEF. Such patients are more often African American carriers of the Val122Ile variant and have worse outcomes. Such data could aid in active ascertainment of ATTRh disease and potentially reduce health disparities in ATTR-CA.