Aterm used for several different diseases/conditions of or problems with the heart muscle. there are many causes of these diseases. likewise, there are many different symptoms and treatments as well. it can affect males and females of all ages and ethnic backgrounds. in this disease, the muscle in the heart gets thick, stiff, thin, or filled with things the body makes but do not belong in the heart. when that happens, the heart has a reduced ability to pump blood, and that usually results in irregular heartbeats, of blood backing up into the lungs (or rest of the body), and/or heart failure. group of answer choices