Key Information
Amyloidosis is a group of diseases which are characterized by the build-up of abnormal deposits of amyloid fibrils. These amyloid fibrils, composed of misfolded proteins, build up in organs throughout the body. Over time, these amyloid deposits may cause affected organs to stop working properly, which can eventually lead to organ failure.
The two most common types of amyloidosis that affect the heart are light chain amyloidosis (AL) and transthyretin amyloid cardiomyopathy (ATTR-CM). Each type of amyloidosis is characterized by the make-up of the amyloid protein that deposits in the body's organs and tissues. Transthyretin amyloid cardiomyopathy (ATTR-CM) is a presentation of ATTR amyloidosis that primarily affects the heart. Over time, ATTR-CM causes the heart muscle to become stiff, eventually leading to heart failure.