Associazione Nazionale Medici Cardiologi Ospedalieri



Prevalence of Wild-Type Transthyretin Cardiac Amyloidosis in Elderly Subjects from the General Population

Aimo Alberto Pisa(Pisa) – Fondazione Toscana G. Monasterio | Vergaro Giuseppe Pisa(Pisa) – Fondazione Toscana G. Monasterio | Castiglione Vincenzo Pisa(Pisa) – Fondazione Toscana G. Monasterio

Background: Wild-type transthyretin cardiac amyloidosis (ATTRwt-CA) affects older adults, and is currently considered as a rare disorder.

Objective: We investigated for the first time the prevalence of ATTRwt-CA in elderly individuals from the general population.

Methods: General practitioners from Pisa, Italy, proposed a screening for ATTRwt-CA to all their patients aged 65-90 years, until 1,000 accepted. The following red flags were searched: interventricular septal thickness ≥12 mm, any echocardiographic, ECG or clinical hallmark of CA, or high sensitivity-troponin T ≥14 ng/L. Individuals with at least one red flag (n=346) were asked to undergo the search for a monoclonal protein and bone scintigraphy, and 216 accepted.

Results: Four patients received a non-invasive diagnosis of ATTRwt-CA. All complained of dyspnoea on moderate effort. A woman and a man aged 79 and 85 years, respectively, showed an intense cardiac tracer uptake (grade 3), left ventricular (LV) wall thickening, grade 2 to 3 diastolic dysfunction, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) >1,000 ng/L. Two other patients (a man aged 74 years and a woman aged 83 years) showed a grade 2 uptake, an increased LV septal thickness, but preserved diastolic function, and NT-proBNP <300 ng/L. The prevalence of ATTR-CA in subjects ≥65 years was calculated as 0.46% (i.e., 4 out of the 870 subjects completing the screening, namely 654 not meeting the criteria for Step 2 and 216 progressing to Step 2). Conclusions: ATTRwt-CA has a prevalence of 0.46% in elderly subjects from the general population.