Abstract
Background: Transthyretin amyloidosis is a multi-system disease that may manifest as cardiomyopathy (ATTR-CM) and/or polyneuropathy. Both disease manifestations are associated with autonomic dysfunction. However, the prevalence of autonomic dysfunction in ATTR-CM remains to be evaluated. Methods: Within the scope of a prospective ATTR-CM registry, the Composite Autonomic Symptom Score-31 (COMPASS-31) questionnaire was applied to consecutive patients between November 2022 and November 2024. Baseline characteristics are described, and associations of the COMPASS-31 score with markers of disease severity were assessed. Kaplan-Meier analysis was utilized to assess the COMPASS-31 score's association with a combined endpoint of all-cause mortality and heart failure-related hospitalizations. Results: A total of 129 ATTR-CM patients [81.7 years (IQR: 77.4-84.3), 108 male (83.7%)] were included in the final study cohort. After stratification using the COMPASS-31 median [14 points, interquartile range (IQR): 6-29], statistically significant differences with regard to New York Heart Association (NYHA) stage and the Kansas City Cardiomyopathy Questionnaire (KCCQ) were observed. Furthermore, the COMPASS-31 score was moderately correlated with the KCCQ score in Spearman correlation analysis (r = -0.55, p < 0.001). The primary endpoint occurred in 16 patients (13 HF-hospitalizations/3 deaths) after 6.3 (IQR: 2.8-17.1) months. In Kaplan-Meier analysis, a COMPASS-31 score above the median of 14 was also associated with the primary endpoint of all-cause mortality and HF-related hospitalization (log-rank p = 0.047). Conclusions: Autonomic dysfunction is highly prevalent in ATTR-CM, affecting almost two-thirds of patients. As the presence of autonomic dysfunction is likely associated with more severely impaired quality of life, routine screening for this disease manifestation of transthyretin amyloidosis may be advisable.