Abstract 15619: Prevalence of Transthyretin Cardiac Amyloidosis in Elderly Subjects From the General Population: The Catch Study

Abstract

Introduction: The exact prevalence of transthyretin cardiac amyloidosis (ATTR-CA) in the general population has never been defined. Methods: We conducted a population screening in an area of Tuscany (Italy) where there is no cluster of variant ATTR. Six general practitioners proposed study participation to a total of 2,566 subjects aged ≥65 years, with 1,000 accepting. All subjects underwent first-line exams searching the following elements of suspicion of CA: high sensitivity-troponin T ≥14 ng/L, interventricular septal thickness ≥12 mm, any echocardiographic, ECG or clinical red flag. Individuals with any of these elements were referred to the search for a monoclonal protein and bone scintigraphy. Results: Step two exams (bone scintigraphy and search for a monoclonal protein) were proposed to 346 subjects, and 216 (62%) accepted. Three patients were ultimately diagnosed with ATTR-CA (a 79-year-old woman, an 85-year-old and a 74-year-old man), and the diagnosis was deemed likely in another patient (an 83-year-old woman with mild bone tracer uptake but intense uptake in the inferior wall, not willing to undergo endomyocardial biopsy). No patient had a monoclonal protein nor TTR gene mutations. All patients with ATTR-CA had left ventricular wall thickening and complained of dyspnea on moderate effort. The prevalence of ATTR-CA was 3 out of 870 (654 [Step two not proposed] + 216 [Step two performed]) = 0.34%, or 0.46% if considering also the fourth case. Conclusions: The prevalence of wild-type ATTR-CA in the elderly population is 0.34% (established diagnoses) or 0.46% (established or likely diagnoses).