What is dilated cardiomyopathy?
Dilated cardiomyopathy is a serious condition that weakens your heart muscle and causes it to stretch, or dilate. When your heart muscle is weak, it can't pump out blood as well as it should, so more blood stays in your heart after each heartbeat. As more blood fills and stays in the heart, the heart muscle stretches even more and gets even weaker.
If your heart gets weaker, you may develop heart failure. Heart failure does not mean that your heart stops pumping. It means that your heart can't pump enough blood to meet your body's needs.
What causes dilated cardiomyopathy?
The most common type of dilated cardiomyopathy develops after a heart attack has damaged the heart muscle. But it can also be caused by many diseases or problems that may or may not be related to your heart. Sometimes the cause is not known.
Some of the things that can lead to dilated cardiomyopathy include:
- Coronary artery disease and heart attack.
- High blood pressure, which can put stress on the heart walls.
- Heart valve diseases, including aortic valve regurgitation and mitral valve regurgitation.
- Heartbeat problems (arrhythmias).
- Myocarditis, which is inflammation of the heart muscle. It may be caused by an infection, certain drugs, or an immune system problem.
- Drinking too much alcohol, using certain illegal drugs such as cocaine, or taking certain medicines such as chemotherapy.
- Being exposed to toxic metals, such as lead or mercury.
- Being pregnant. In rare cases, dilated cardiomyopathy develops toward the end of pregnancy or during the first 6 months after a woman gives birth. Experts don't know why this happens.
- Having a family history of dilated cardiomyopathy.
What are the symptoms?
You may not have any symptoms at first. Or you may have mild symptoms, such as feeling very tired or weak.
If your heart gets weaker, you may develop heart failure. If this happens, you will feel other symptoms, including:
- Shortness of breath, especially with activity.
- Trouble breathing when you lie down.
- Swelling in your legs.
You may get these symptoms slowly, over months or years. Or you may get them suddenly, such as after pregnancy or an illness caused by a virus.
Heart failure that suddenly gets worse is an emergency. Get medical help right away if:
- You have severe trouble breathing.
- You cough up pink, foamy mucus.
- You have a new irregular or rapid heartbeat.
Keeping track of your symptoms every day is important. Call your doctor if:
- You have a sudden weight gain, such as more than 2 lb (0.9 kg) to 3 lb (1.4 kg) in a day or 5 lb (2.3 kg) in a week. (Your doctor may suggest a different range of weight gain.)
- Your ability to exercise changes.
- You have any change in your symptoms.
How is dilated cardiomyopathy diagnosed?
Your doctor will ask questions about your symptoms and past health. He or she will want to know about recent illnesses and about heart disease in your family. Your doctor will listen to your heart and lungs and check your legs for fluid buildup.
You may also have other tests, including:
- An electrocardiogram, also known as an ECG or EKG.
- A chest X-ray.
- An echocardiogram.
- Magnetic resonance imaging (MRI).
- Blood tests.
In some cases, a doctor may want to look at a small sample of heart tissue, called a biopsy, to make a definite diagnosis.
How is it treated?
Treatment for dilated cardiomyopathy focuses on relieving your symptoms, improving heart function, and helping you live longer. You may also have treatment for the cause of the cardiomyopathy.
You will probably need to take several medicines. It is very important to take your medicines exactly as your doctor tells you to and to keep taking them. If you don't, your heart function could get worse.
Your doctor may suggest a mechanical device to help your heart pump blood or to prevent life-threatening irregular heart rhythms. Such devices include a pacemaker for heart failure (also called cardiac resynchronization therapy or CRT), an implantable cardioverter-defibrillator (ICD), or a combination pacemaker and ICD. If your condition is very bad, a heart transplant may be an option.
Self-care is an important part of your treatment. Self-care includes the things you can do every day to feel better, stay healthy, and avoid the hospital.
Take your medicines as prescribed. This gives you the best chance of being helped by them. Some medicines include:
- Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs). These make it easier for blood to flow.
- Diuretics. These help remove excess fluid from the body.
- Beta-blockers. These slow the heart rate and can help the heart fill with blood more completely.
- Live a healthy lifestyle. Limit salt, try to get regular exercise, and don't smoke.
- Watch for signs you're getting worse. Weighing yourself every day to watch for sudden weight gain is a good way to do this.
What can you expect with dilated cardiomyopathy?
If your heart gets weaker, you may develop heart failure. If the cause of dilated cardiomyopathy can be treated, this can slow or stop the progression of the disease. For some types of cardiomyopathy, treatment can help the heart work better.
Some people develop other problems, including:
- Heart attack.
- Sudden cardiac death, which means the heart suddenly stops working. This may be more likely to happen to people who have serious rhythm problems (arrhythmias) in one of the lower heart chambers (ventricles).
If a woman gets dilated cardiomyopathy from pregnancy, she should not get pregnant again. This is true even if her heart problem gets better.
If your disease is getting worse, you may want to think about making end-of-life decisions. It can be comforting to know that you will get the type of care you want.
Other Works Consulted
- Falk RH, Hershberger RE (2015). The dilated, restrictive, and infiltrative cardiomyopathies. In DL Mann et al., eds., Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 10th ed., vol. 2, pp. 1551–1573. Philadelphia: Saunders.
- Mestroni L, et al. (2011). Dilated cardiomyopathies. In V Fuster et al., eds., Hurst's the Heart, 13th ed., vol. 1, pp. 821–836. New York: McGraw-Hill.
- Yancy CW, et al. (2013). 2013 ACCF/AHA Guideline for the management of heart failure: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Journal of the American College of Cardiology, 62(16): e147–e239.
Current as of: August 31, 2020
Author: Healthwise Staff
Rakesh K. Pai MD, FACC - Cardiology, Electrophysiology
E. Gregory Thompson MD - Internal Medicine
Martin J. Gabica MD - Family Medicine
Adam Husney MD - Family Medicine
George Philippides MD - Cardiology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.