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. 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. This doesn't mean that your heart stops pumping. It means that your heart can't pump enough blood to meet your body's needs.
What causes it?
Dilated cardiomyopathy can be caused by many diseases or problems that may or may not be related to your heart. Sometimes the cause isn't known.
Some of the things that can lead to dilated cardiomyopathy include:
- Heartbeat problems (arrhythmias).
- Myocarditis. This 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.
How is it 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 will check your legs for fluid buildup.
You may also have other tests. These include:
- An electrocardiogram, also known as an ECG or EKG.
- A chest X-ray.
- An echocardiogram.
- Cardiac catheterization.
- An MRI (magnetic resonance imaging).
- 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 dilated cardiomyopathy 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. They include:
- Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs).
These make it easier for blood to flow.
These help remove excess fluid from the body.
These slow the heart rate and can help the heart fill with blood more completely.
It's very important to take your medicines exactly as your doctor tells you to. And make sure 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. These devices include:
- A pacemaker for heart failure (also called cardiac resynchronization therapy or CRT).
- An implantable cardioverter-defibrillator (ICD).
- A combination pacemaker and ICD.
If your condition is very bad, a heart transplant may be an option.
What can you expect?
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.
If your heart gets weaker, you may develop heart failure. Some people develop other problems, including:
- Heart attack.
- A blood clot in the lung, called a pulmonary embolism.
- Sudden cardiac death (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 you are woman who got dilated cardiomyopathy from pregnancy, talk with your doctor about your risk of problems from another pregnancy.
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.
Current as of: June 25, 2023
Author: Healthwise Staff
Clinical Review Board: All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.