A heart muscle weakening, or cardiomyopathy, is diagnosed on the basis of the individual’s personal history, his family history, and the results of physical examinations and tests, according to the National Heart, Lung, and Blood Institute. Tests including echocardiography, blood tests and electrocardiograms are used.
Examining physical symptoms is the first step for diagnosing cardiomyopathy, and a stethoscope is often used in this early stage to identify the type of cardiomyopathy, the National Heart, Lung, and Blood Institute explains. A weakening heart may present symptoms such as swelling of the abdomen, ankles or feet. The location, rhythm and loudness of the sounds are signs of the cardiomyopathy type.
An EKG is often used to identify heart problems, but its chief limitation is that it can only identify symptoms that occur while the doctor performs the test, the National Heart, Lung, and Blood Institute notes. To test heart performance in a wider range of situations, the patient is required to wear a Holter or event monitor. A Holter captures the electrical activity of the heart during a longer period, typically 24 to 48 hours. An event monitor captures the electrical activity only occasionally when symptoms occur. An event monitor may either be activated by the patient’s input or automatically when it detects a certain type of heart activity.