Clinical, Genetic and Phenotypic Characterization of Hereditary Transthyretin Amyloidosis (ATTRv) in Peruvian Population: Real-World Data from a Case Series — IMPAC-FE Study

Background: Hereditary transthyretin amyloidosis (ATTRv) is a rare multisystemic disease with variable phenotypic expression. No published data exist on the clinical characteristics of ATTRv in Peruvian population.Objective: To describe the demographic, genetic, and clinical characteristics of patients with ATTRv in Peru, and to determine the distribution of clinical phenotypes according to internationally validated criteria.Methods: Descriptive, observational, retrospective case series of patients with ATTRv confirmed by molecular genetic testing, evaluated in Lima, Peru, between 2021 and December 2025 (IMPAC-FE study). Demographic, genetic, neurological (NIS, Norfolk QOL-DN, PND), autonomic (COMPASS-31, SUDOSCAN), and cardiovascular variables (echocardiography, septal thickness, E/e', apical sparing pattern, Tc99m-pyrophosphate scintigraphy, NT-proBNP, troponin) were evaluated. Phenotypes were classified according to AHA/ACC criteria and the THAOS registry.Results: Twenty-three patients were included (69.6% male, median age 60 years, IQR 45-70). The variants were Val142Ile (56.5%), Ala65Val (34.8%), and Val50Met (8.7%). Overall phenotype distribution: preclinical 34.8%, mixed 39.1%, cardiac 21.7%, neurological 4.3%. Norfolk QOL-DN (n=18): median 6.0. COMPASS-31 (n=18): median 6.0. LVEF (n=16): mean 60.5%. LV Mass (n=12): mean 102.9g. Troponin T (n=9): median 47 ng/L. PYP Scintigraphy (n=9): Perugini 3 in 77.8%.Conclusions: This first case series of ATTRv in Peruvian population shows clinical and genetic heterogeneity, with predominance of Val142Ile and Ala65Val variants, and a phenotypic distribution compatible with international registries. The high proportion of preclinical patients and extended cardiovascular evaluation reinforce the need for early diagnosis and timely initiation of disease-modifying therapies.