Other names: Cardiomyopathy of Transthyretin-Mediated Amyloidosis

Amyloid cardiomyopathy (cardiac amyloidosis) is a heart disorder that is caused by an abnormal type of protein (amyloid) building up within the heart tissues. This eventually reduces the ability for the heart to work properly, either having problems filling or pumping. The amyloid deposits may also affect the electrical conduction in the heart which can lead to arrhythmias (abnormal heartbeats) and heart block.

There are two main proteins that cause cardiac amyloidosis. One protein is called amyloid light chain (AL) and the other protein is amyloid transthyretin (ATTR). Subtypes of ATTR include wild-type ATTR (ATTRwt), which has normal amyloid transthyretin protein that is slowly deposited within the heart over many years and causes age related amyloidosis. In mutant ATTR (ATTRm) amyloidosis subtype there is a mutation in the transthyretin gene which causes amyloid deposits to accumulate at a faster rate.

Definitive diagnosis of the subtype of amyloidosis is crucial to understand the disease form, progression, treatment and prognosis.

There are two aspects of managing of amyloid cardiomyopathy. The first point is treating cardiac symptoms of heart failure, arrhythmias and pericardial complications. The other aspect of treatment is to reduce amyloid deposition.

For AL amyloidosis chemotherapy is used to slow the progression of amyloid accumulation. In ATTR amyloidosis, depending of the specific subtype, selective stabilizers of TTR may be used to slow down the process of amyloid formation.

Drugs used to treat Amyloid Cardiomyopathy