Cardiac amyloidosis-interdisciplinary approach to diagnosis and therapy.

Abstract

The vast majority of cardiac amyloidosis (CA) cases are caused by light chain (AL) or transthyretin (ATTR) amyloidosis. The latter is divided into hereditary (ATTRv) and wild-type forms (ATTRwt). The incidence of ATTRwt amyloidosis has significantly increased, particularly due to the improved diagnosis of cardiac manifestations, with relevant proportions in patient populations with heart failure (HF) and preserved ejection fraction (HFpEF). Cardiac amyloidosis should be suspected in HF with indicative clinical scenarios/"red flags" with typical signs of CA in echocardiography. Further noninvasive imaging (cardiovascular magnetic resonance imaging, scintigraphy) and specific laboratory diagnostics are important for the diagnosis and typing of CA into the underlying main forms of ATTR and AL amyloidosis. The histopathologic analysis of an endomyocardial biopsy is necessary if noninvasive diagnostic methods do not enable reliable typing of CA. This is crucial for initiating specific therapy. Therapy of HF in CA is largely limited to the use of diuretics in the absence of evidence on the benefit of classic HF therapy with neurohormonal modulators. Innovative therapies have been developed for amyloidosis with improvement in organ protection, prognosis, and quality of life. These include specific cytoreductive therapies for monoclonal light-chain disease in AL amyloidosis and pharmacologic stabilization or inhibition of transthyretin expression in ATTR amyloidosis. Since the CA underlying amyloidosis is asystemic disease also affecting other organ systems, close interdisciplinary cooperation is crucial for rapid and effective diagnosis and therapy.