P208 PREVALENCE OF TRANSTHYRETIN CARDIAC AMYLOIDOSIS IN PATIENTS HOSPITALIZED FOR HEART FAILURE

Background Bone scintigraphy with labeled diphosphonates allows for the non–invasive diagnosis of transthyretin cardiac amyloidosis, in case of high cardiac uptake of the radiotracer and concomitant absence of serum monoclonal component (Gillmore algorithm). Objective The aim of this study was to establish the prevalence of transthyretin cardiac amyloidosis in a population of patients hospitalized for heart failure. Methods In this prospective observational study, patients hospitalized for heart failure at the Cardiology Unit of Castelsangiovanni Hospital were evaluated in the period from 1 January 2021 to 31 July 2022. Twenty–five of them, who presented with echocardiographic moderate to severe left ventricular hypertrophy (i.e. maximum end–diastolic thickness of the interventricular septum ≥ 15 mm), were included in the study. All patients underwent anamnesis, physical examination, 12–lead electrocardiogram and transthoracic echocardiogram. Patients were divided into 2 groups according to the presence or absence of the following clinical, electrocardiographic and echocardiographic diagnostic red flags: history of carpal tunnel syndrome and/or rupture of the long head of the brachial biceps, low voltage QRS, granular sparkling of the ventricular myocardium, apical sparing pattern of the global longitudinal strain. Results Fifteen patients with heart failure, left ventricular hypertrophy and at least one diagnostic red flag were screened for cardiac amyloidosis by: a) search for a serum monoclonal component; b) bone scintigraphy with labeled diphosphonates. In thirteen patients, an high cardiac uptake of the radiotracer was found on bone scintigraphy. One patient with high cardiac uptake also presented a serum monoclonal component and was referred for tissue biopsy. In the remaining twelve patients (85% of the cases studied) a non–invasive diagnosis of transthyretin cardiac amyloidosis was made. In six patients affected by transthyretin cardiac amyloidosis, a salivary genetic test was also performed to search for mutations in the transthyretin gene, which resulted negative in all cases examined. Conclusions In this study of patients hospitalized for decompensated heart failure, rigorous application of Gillmore‘s algorithm in suspected cases led to non–invasive diagnosis of cardiac transthyretin amyloidosis in 85% of cases, without wasting healthcare resources.