What Is Dilated Cardiomyopathy?

Dilated cardiomyopathy is a condition that weakens the heart muscle and causes the heart chambers to become enlarged. As the heart stretches, it cannot pump blood as effectively as it should.

Over time, this can reduce blood flow to the body and lead to problems such as heart failure or irregular heart rhythms. Some people develop symptoms slowly, while others notice changes more quickly.

There are many possible causes of dilated cardiomyopathy. In some cases, the exact cause is never identified.

Possible causes and risk factors include:

• Family history of heart muscle disease
• High blood pressure
• Coronary artery disease or previous heart attack
• Viral infections
• Diabetes or thyroid disorders
• Heavy alcohol use
• Illegal drug use
• Certain chemotherapy medicines
• Autoimmune conditions
• Pregnancy-related heart changes
• Exposure to harmful toxins

Symptoms

Dilated cardiomyopathy may begin with mild symptoms or no symptoms at all. As the heart becomes weaker, everyday activities can become more difficult.

Common symptoms include:

• Shortness of breath during activity or while resting
• Trouble breathing when lying flat
• Fatigue or low energy
• Swelling in the legs, ankles, feet, or abdomen
• Fast or irregular heartbeat
• Dizziness or fainting
• Reduced ability to exercise
• Persistent cough or chest congestion

How Is It Diagnosed?

Providers diagnose dilated cardiomyopathy by reviewing your symptoms, medical history, and family history. A physical exam can help identify signs of fluid buildup or changes in heart function.

Tests commonly used to confirm the diagnosis include:

• Echocardiogram to evaluate heart size and pumping strength
• Electrocardiogram (ECG) to check heart rhythm
• Chest X-ray or cardiac MRI for detailed heart images
• Blood tests to look for underlying conditions
• Heart rhythm monitoring
• Stress testing or cardiac catheterization when needed

Genetic testing may also be recommended if an inherited condition is suspected.

How Is It Treated?

Treatment focuses on helping the heart work more effectively, improving symptoms, and lowering the risk of complications. Care plans are personalized based on the cause and severity of the condition.

Treatment may include:

• Managing underlying health conditions such as high blood pressure or diabetes
• Heart-healthy lifestyle changes
• Reducing salt and alcohol intake
• Medications to improve heart function and control symptoms
• Diuretics to reduce swelling and fluid buildup
• Medicines to manage abnormal heart rhythms or prevent blood clots

Some people may benefit from advanced therapies such as an implantable cardioverter-defibrillator (ICD) to help prevent dangerous heart rhythms. In severe cases, surgery or heart transplant evaluation may be considered.

With ongoing care and regular follow-up, many people are able to manage symptoms and maintain daily activities.