CONTEMPORARY REVIEWS Updates in Cardiac Amyloidosis: A Review

S ystemic amyloidosis is a relatively rare multisystem disease caused by the deposition of misfolded protein in various tissues and organs. It may present to almost any specialty, and diagnosis is frequently delayed.1 Cardiac involvement is a leading cause of morbidity and mortality, especially in primary light chain (AL) amyloidosis and in both wild-type and hereditary transthyretin amyloidosis. The heart is also occasionally involved in acquired serum amyloid A type (AA) amyloidosis and other rare hereditary types. Clinical phenotype varies greatly between different types of amyloidosis, and even the cardiac presentation has a great spectrum. The incidence of amyloidosis is uncertain, but it is thought that the most frequently diagnosed AL amyloidosis has an annual incidence of 6 to 10 cases per million population in the United Kingdom and United States. Amyloidosis due to transthyretin deposition (ATTR) can be wild-type transthyretin amyloid deposits, which predominantly accumulate in the heart and are very common at autopsy in the elderly. Although the associated clinical syndrome known as senile systemic amyloidosis is diagnosed rarely in life,2 there is increasing evidence that this disorder is much underdiagnosed and that with increasing longevity and improved diagnostic methods it may be identified as a substantial public health problem. This review focuses on recent progress in the field: novel diagnostic and surveillance approaches using imaging (echocardiography, cardiovascular magnetic resonance), biomarkers (brain natriuretic peptide [BNP], high-sensitivity troponin), new histological typing techniques, and current and future treatments, including approaches directly targeting the amyloid deposits.3