A review of the criteria for non-invasive diagnosis of cardiac transthyretin amyloidosis

ABSTRACT Introduction: Cardiac transthyretin (ATTR) amyloidosis is a progressive and fatal infiltrative cardiomyopathy (ATTR-CM) characterized by congestive cardiac failure, often with preserved left ventricular ejection fraction, and significant risk of conduction disease. Diagnosis is often delayed or missed due to poor specificity of echocardiography and the historical requirement for a histological diagnosis, frequently an endomyocardial biopsy. Areas covered: Following a detailed literature review focusing on peer reviewed articles (Pubmed, Cochrane Library, Google Scholar), from 1995 to 2020, alongside international diagnostic guidelines and expert opinion in the field, this article will explore the current non-invasive diagnostic criteria for ATTR-CM including the role of transthoracic echocardiography, cardiac MRI, bone scintigraphy, and assessment for exclusion of a clonal dyscrasia. Expert opinion: ATTR-CM is an emerging and increasingly diagnosed cause of heart failure, particularly in the elderly. Promising novel therapies make accurate and swift diagnosis of the disease vital. With the increasing use of cardiac MRI to investigate cardiomyopathy and repurposing of technetium-labeledbone scintigraphy, clinicians are now often able to diagnose ATTR-CM without recourse to an endomyocardial biopsy.