Dilated Cardiomyopathy (DCM): Symptoms, Causes, Treatment, Diagnosis & Outlook

Cardiomyopathy is a heart muscle condition that impedes the ability of the heart to pump blood to other parts of the body and may cause heart failure. It is categorized into three types: dilated, hypertrophic, and restrictive.

Dilated cardiomyopathy is a form of muscle disease in which the heart chambers (ventricles) thin and stretch, causing them to grow larger. It generally starts in the heart's main pumping chamber (left ventricle).

Dilated cardiomyopathy impairs the heart's capacity to supply blood to the rest of the body. Men are more likely to develop dilated cardiomyopathy.

Symptoms of Dilated Cardiomyopathy

Numerous people with dilated cardiomyopathy experience no symptoms, particularly in the early stages. Symptoms become more noticeable as heart function deteriorates. A heart murmur is frequently the first symptom. Symptoms of dilated cardiomyopathy may also include:

• Fatigue
• Congestion and cough
• Feeling dizzy or light-headed
• Convulsing
• Dyspnea (shortness of breath) during activity or while lying down
• Oedema (swelling) of the legs, ankles, feet, or abdomen
• Pain or discomfort in the chest
• A heartbeat that is rapid, fluttering, or pounding (palpitations)
• Unusual weight gain as a consequence of fluid retention

Although the most common type is dilated cardiomyopathy, it can be caused by various underlying conditions. Some doctors use the term to refer to a specific condition known as idiopathic dilated cardiomyopathy. This type of dilated cardiomyopathy has no known cause.

Causes of Dilated Cardiomyopathy

The catalyst of dilated cardiomyopathy may be challenging to pinpoint. The following are the most common reasons for dilated cardiomyopathy:

• A narrowing or blockage of the coronary arteries causes heart disease.
• Well-controlled high blood pressure.

Many factors, however, can end up causing the left ventricle to dilate and weaken, including:

• A few infections
• Late-stage pregnancy complications
• Diabetes
• Excess of iron in the heart and other organs (hemochromatosis)
• Heart rhythm issues (arrhythmias)
• Blood pressure is high (hypertension)
• Obesity
• Mitral valve or aortic valve regurgitation is a type of heart valve disease.

Other causes of dilated cardiomyopathy include: 

• Misuse of alcohol
• Toxin exposure, such as lead, mercury, and cobalt
• Certain cancer medications
• Illicit drug use, such as cocaine or amphetamines 

The medical practitioner will begin by understanding the medical history and performing a physical exam to diagnose cardiomyopathy. This could include listening to the lungs for fluid buildup. Screening helps determine the magnitude and aids healthcare providers in treating dilated cardiomyopathy. You may require the following:

• Angiography
• Blood tests
• Echocardiogram
• Electrocardiogram (EKG)
• Stress test with exercise
• Genetic testing
• Heart biopsy

Diagnosis of Dilated Cardiomyopathy

Several tests can be performed to confirm cardiomyopathy.

• Chest x-ray: It will show if the heart is enlarged.
• Electrocardiogram: Electrical signals from the heart are measured by attaching electrode patches to the skin. It records the electrical activity of the heart and detects irregular heartbeat.
• Treadmill Stress Test: You are asked to walk on a treadmill while your heart rhythm, blood pressure and breathing are monitored. This test determines if the exercise is triggering irregular heart rhythm.
• Blood Tests: Blood tests check levels of B-type natriuretic peptide, a protein produced in the heart. Its level rises during heart failure.  
• Genetic Tests: Cardiomyopathy can be inherited from parents. Genetic screening includes testing parents, siblings and children.

Treatment of Dilated Cardiomyopathy

Treatment may be required depending on the complexity of the condition. Medications to improve heart function may be the first step in the treatment plan. Examples of some of these medications are:

• Beta-blockers
• ACE Inhibitors
• Aldosterone receptor antagonists (ARB)
• Angiotensin-converting enzyme-neprilysin inhibitors (ARNi)
• Diuretics
• Anti-arrhythmics to treat irregular heartbeat
• Blood thinners (anticoagulants)

Lifestyle changes can enhance the effectiveness of prescription drugs and help individuals delay or avoid a procedure. These modifications include:

• Changing unhealthy habits: You may be able to drink alcohol in moderation. Quitting recreational drug use can benefit the heart. To reduce your risk of viral hepatitis and HIV, you should use condoms.
•  Consumption of a heart-healthy diet: Consume lean proteins such as chicken, fish, and fruits and vegetables. A low-sodium diet can help prevent fluid buildup, which puts your heart under additional strain.
• Enhanced physical activity: Light exercises can help your heart function better. A cardiac rehabilitation program provides a secure setting in which to begin.

Heart function may be seriously undermined if you have advanced dilated cardiomyopathy. You may require implantable gadgets that can assist the heart in pumping harder or more frequently. Among the options are:

• Pacemaker with two ventricles: This device is intended for people who suffer from heart failure and irregular heartbeats. A biventricular pacemaker stimulates both lower heart chambers (the right and left ventricles) to improve heart rate.
• Implantable Cardioverter-defibrillators (ICD): An ICD does not treat cardiomyopathy. It detects irregular heartbeats (arrhythmia) and delivers electrical shocks if required. Cardiomyopathy can result in dangerous arrhythmias, such as those that cause the heart to stop beating.
• Left ventricular assist devices (LVADs): These mechanical devices assist a weakened heart in pumping more efficiently. LVAD is considered when less invasive treatments fail. It can be used as a long-term or short-term treatment while waiting for a heart transplant.

Additional surgical procedures include:

• Surgery for heart failure to improve heart function
• Heart transplant 

Outlook of Dilated Cardiomyopathy Disease

This condition is not always preventable — particularly if it has a family history or is a consequence of life-saving treatment, such as chemotherapy. Certain contributing factors, however, are under your control. 

You can avoid dilated cardiomyopathy by avoiding cocaine, consuming alcohol in moderation, and controlling diabetes and high blood pressure.

The cause and severity of the disease determine the prognosis. Following treatment, many people return to work and daily activities. Advanced dilated cardiomyopathy and its complications can be fatal. You may need to be admitted to the hospital until your symptoms improve.