In the most simplistic sense cardiomyopathy means a diseased and weakened heart and no more than that. It is therefore never enough as a complete diagnosis. The nature of the cardiomyopathy needs to be described further 

Most cardiomyopathies are diagnosed and further stratified either on the basis of the visual appearance of the heart on some form of imaging modality or on the basis of an electrical disturbance on the ECG. The appearance can give a clue to the aetiology and the aetilogy should also form part of the complete diagnosis. 

In terms of visual appearance, the heart may look abnormally muscular or hypertrophied in which case it is described as hypertrophic cardiomyopathy. Anything that increases the heart to work against a higher pressure can cause a hypertrophic cardiomyopathy. Some people can have an inherited disorder which  causes an abnormally muscular heart and this is then called familial hypertrophic cardiomyopathy. 

Sometimes the heart looks abnormally enlarged and flabby in which case it is called a dilated cardiomyopathy. This in turn can also be caused by a variety of causes. Excessive alcohol use over a number of years can cause this in which case it is called alcohol-related dilated cardiomyopathy. Sometimes it can be due to a virus (viral dilated cardiomyopathy) and sometimes it can even be inherited (familial dilated cardiomyopathy) 

The most common form of cardiomyopathy is ischaemic cardiomyopathy which results from a heart attack. In this, the affected part of the heart does not contract as well but the other parts do and this is described as regional wall abnormality and suggests the diagnosis.