Dilated Cardiomyopathy

What Is Dilated Cardiomyopathy?

Dilated cardiomyopathy (DCM) is the most common type of cardiomyopathy. With DCM, the heart muscle gets larger, as the "dilated" in its name implies.
Image of hearts showing a normal and a dilated cardiomyopathy heart

To understand what happens to the heart with DCM, imagine that the heart muscle is like a rubber band. As that rubber band stretches over time, it eventually loses its "snap" or elasticity.

Likewise, as the heart muscle stretches and the heart gets larger, the heart muscle loses some of its ability to pump or contract. Over time, as heart failure develops, the heart becomes less able to pump blood to the body as strongly as it did before.

Often the cause of DCM is hard to find for a patient. But sometimes doctors find the cause to be a virus, coronary artery disease, or alcoholism. Sometimes DCM is inherited.

Most of the time a person with DCM has no symptoms until heart failure develops. Then the person notices heart failure symptoms: fatigue, shortness of breath, or tissue swelling — often in the legs and feet.

How Is DCM Treated?

Many of the treatments for dilated cardiomyopathy are the same as the treatments for heart failure:

  • Lifestyle changes — Your doctor might suggest that you cut back on the salt (sodium) in your diet and get daily exercise.
  • Medications — Beta blockers and ACE (angiotensin converting enzyme) inhibitors are two medications often used to treat DCM. If you have swelling, your doctor may also prescribe water pills (diuretics).
  • Cardiac devices — If cardiomyopathy makes your heart pump in an uncoordinated way, you might receive an implantable cardiac resynchronization therapy (CRT) device. This device sends tiny amounts of electrical energy to your heart to help re-coordinate the pumping. If you are at risk for dangerous arrhythmias, you might also receive an implantable cardioverter defibrillator. The defibrillator can stop an arrhythmia before it causes sudden cardiac death.
  • Surgery — Some patients may need surgery to repair a heart valve. Or, doctors may consider a heart transplant for patients with very severe symptoms.