Transthyretin cardiac amyloidosis in aortic stenosis: prevalence, diagnostic challenges and clinical implications.

Transthyretin cardiac amyloidosis (ATTR-CA) is a challenging and underdiagnosed cause of heart failure. Advances in cardiac imaging enabled noninvasive diagnosis of ATTR-CA, causing the recent upsurge in disease awareness and detection. ATTR-CA has been increasingly recognized in patients with degenerative aortic stenosis (AS). With the growing number of elderly patients undergoing aortic valve intervention, the identification of ATTR-CA in this group of patients is of high clinical importance. Timely and correct diagnosis is essential for amyloid directed therapies, as well as deciding on AS treatment strategy. This review provides a comprehensive overview of the recent studies investigating coexistence of these two entities. We present the data on the prevalence of ATTR-CA in AS and their prognostic associations. Since diagnosis of ATTR-CA may be challenging, special attention is paid to the diagnostic utility of different imaging modalities, echocardiography, cardiovascular magnetic resonance, nuclear imaging, and distinctive imaging features in patients with dual pathology. We also present a flow diagram summarizing integrated imaging in patients with suspected ATTR-CA