Disease due to heart muscle failure - cardiomyopathy
- cardio means "heart",
- myo means "muscle",
- pathy means "disease".
Cardiomyopathy, therefore, means disease of the heart muscle. Cardiomyopathy can be further described by its cause or by the type of pumping defect that is present. For instance, cardiomyopathy caused by alcoholism is called alcoholic
There are three basic types of cardiomyopathy, which are distinguished by the kind of muscle problem involved:
1. Dilated cardiomyopathy, in which the heart muscle becomes weak and the heart chambers subsequently enlarge (dilate)
Enlarged heart is an increase in the size of the heart that is detected by physical examination, x-ray, or other imaging tests. It may occur as a result of a thickening of the heart muscle in response to increased workload (such as in valve disease or hypertension . Enlarged heart may also be a dilation (expansion) of the heart in response to muscle damage that causes weakened muscle action. Examples include myocardial infarction, congestive heart failure and
2. Hypertrophic cardiomyopathy. (hyper -- "over, trophic -- "feeding") The heart muscle is much thicker than normal.
In this condition, the muscle of the left ventricle is larger than normal. In one form of the disease, the wall between the two ventricles becomes enlarged and obstructs the blood flow from the left ventricle.
Besides obstructing blood flow, the thickened wall sometimes distorts one leaflet of the mitral valve, causing it to become leaky. In over half the cases, the disease is hereditary. Close blood relatives (parents, children or siblings) of such persons often have an enlarged septum, although they may have no symptoms. This disease is most common in young adults. In the other form of the disease, non-obstructive hypertrophic cardiomyopathy, the enlarged muscle does not obstruct blood flow.
3. Restrictive cardiomyopathy.
This is the least common type of cardiomyopathy. Here, the heart becomes excessively "rigid" and cannot fill efficiently during diastole, the period of the heartbeat when the heart relaxes or dilates, and becomes filled with blood. This type is usually due to another disease process.
ęCopyright TQ Team 25896, 1999. The Circulatory System- Online Learning.