There are three basic types of cardiomyopathy.
Dilated cardiomyopathy is the most common type.
The ventricles are enlarged and weak and do not pump blood well. The heart muscle of the ventricles thickens, which causes the cavity of the ventricles to be smaller than normal. The third type, and the rarest form of cardiomyopathy is restrictive cardiomyopathy. Again, the heart muscle walls of the ventricles become very thick. In many cases, no cause can be found for the cardiomyopathy, regardless of the type.