Enlarged Heart: Symptoms, Causes & Treatment

An enlarged heart is not a disease, but a condition caused by problems like heart failure, coronary artery disease, valve disorders, or arrhythmias. These conditions can make the heart muscle thicker or cause the chambers to stretch, leading to an increase in heart size.

An enlarged heart (cardiomegaly) is more common in older adults, but it can also occur in younger people and children with heart conditions. In early stages, it may not cause symptoms, but over time it can lead to fatigue, shortness of breath, and difficulty pumping blood effectively.

This condition can be diagnosed with tests like X-rays, ECG, or echocardiograms, and treatment depends on the underlying cause. Management may include medications, lifestyle changes, medical devices, or surgery, and early treatment can improve outcomes and reduce complications.

Main symptoms

Symptoms of an enlarged heart often develop gradually and may appear in stages. Common symptoms include:

• Shortness of breath during physical activity, at rest, or when lying on your back

• Palpitations

• Chest pain

• Cough, especially when lying down

• Dizziness or fainting

• Weakness or fatigue with minimal activity

• Persistent fatigue

• Swelling in the legs, ankles, or feet

• Abdominal swelling

In its early stages, cardiomegaly often does not cause symptoms. As it progresses, however, the heart may become less efficient at pumping blood to the rest of the body. According to the American Heart Association, these symptoms can occur when the heart cannot pump enough blood to meet the body’s needs

You should see a cardiologist if you notice any symptoms. Seek immediate medical care at the nearest emergency department if you develop symptoms of a heart attack, such as chest pain or difficulty breathing.

Stages of cardiomegaly

An enlarged heart can be assessed on a chest X-ray using the cardiothoracic ratio and classified into four stages:

Why does the heart get bigger?

The heart can enlarge in response to conditions that cause systemic inflammation and increase oxidative stress. These factors lead to thickening and stretching of the heart muscle.

As a result, the heart’s ability to contract effectively is impaired, forcing it to work harder to pump blood throughout the body. Over time, this increased workload causes further enlargement of the heart muscle and may lead to fatigue and heart failure.

Confirming a diagnosis 

Cardiomegaly is diagnosed based on clinical history and imaging or cardiac tests, such as a chest X-ray, ECG, echocardiogram, CT scan, or MRI. Blood tests may also be ordered to identify abnormalities that could affect heart function.

In some cases, the cardiologist may recommend cardiac catheterization to examine the heart from the inside. During this procedure, a biopsy can be performed to evaluate heart cells for abnormalities.

Possible causes 

An enlarged heart can occur as a result of several conditions, including:

• Systemic arterial hypertension

• Coronary artery disease, such as arterial blockage

• Heart failure

• Cardiac arrhythmias

• Cardiomyopathy

• Myocardial infarction (heart attack)

• Valvular disease due to rheumatic fever or infections such as endocarditis

• Diabetes

• Pulmonary hypertension

• Chronic obstructive pulmonary disease (COPD)

• Kidney failure

• Anemia

• Thyroid disorders, such as hypothyroidism or hyperthyroidism

• Iron overload

• Chagas disease

• Excessive alcohol use

Certain medications, particularly some chemotherapy drugs such as doxorubicin, epirubicin, daunorubicin, and cyclophosphamide, can also lead to cardiomegaly.

While uncommon, some women may develop an enlarged heart during pregnancy. It is more likely in those with prior heart disease, older maternal age, or substance use. In most cases, it is temporary and resolves within a year with treatment.

Can an enlarged heart return to its normal size? 

Some people may experience cardiomegaly as a result of a temporary condition, like an infection or pregnancy. In these cases, the heart can return to its normal size with the right treatment. 

However, when it is caused by a chronic condition, the enlargement may be permanent. In these situations, following the prescribed treatment is important to help manage symptoms.

Treatment options

Treatment for cardiomegaly should be monitored by a cardiologist. Some treatment options include: 

1. Medications

Medications a cardiologist may prescribe include:

• Diuretics, such as furosemide or indapamide: These help remove excess fluid from the body, preventing fluid buildup that can interfere with heart function. They also reduce swelling in the abdomen, legs, feet, and ankles.

• Antihypertensives, such as captopril, enalapril, losartan, valsartan, carvedilol, or bisoprolol: These medications help relax and widen blood vessels, improving blood flow and reducing the workload on the heart.

• Anticoagulants, such as warfarin or aspirin: These reduce the blood’s tendency to clot, helping to prevent blockages and lower the risk of stroke.

• Antiarrhythmics, such as digoxin: These help regulate heart rhythm and improve the strength and efficiency of heart contractions.

These medications should be used under medical supervision, with doses tailored to your individual needs.

2. Pacemaker

In some cases of cardiomegaly, particularly in advanced stages, a doctor may recommend a pacemaker to help coordinate the heart’s electrical signals and contractions. This can improve heart function and make it easier for the heart to pump blood.

3. Cardiac surgery

A cardiologist may recommend surgery to correct defects or abnormalities in the heart valves. The procedure may involve repairing or replacing the affected valve.

4. Coronary bypass surgery 

Coronary bypass surgery may be recommended when an enlarged heart is caused by coronary artery disease. This procedure restores blood flow in the coronary arteries and can help relieve symptoms such as chest pain and shortness of breath.

5. Heart transplant

A heart transplant may be considered if other treatments fail to control the symptoms of cardiomegaly. It is typically reserved as a last resort.

Possible complications

Possible complications of an enlarged heart include heart attack, blood clots, cardiac arrest, and sudden death. The risk depends on which part of the heart is enlarged, the underlying cause, and whether treatment is started promptly.

Urgent medical evaluation is recommended for symptoms of a heart problem, such as chest pain, shortness of breath, or fainting.

How long can a person live with an enlarged heart? 

Because cardiomegaly can result from many different causes, it is not possible to predict life expectancy for someone with this condition. Outcomes vary depending on the underlying cause and the individual’s overall health.

Without appropriate treatment, the condition may worsen over time, potentially reducing quality of life and increasing the risk of serious complications, including death. For this reason, it is important to seek evaluation and guidance from a cardiologist.

Lifestyle changes

Some important measures during treatment for cardiomegaly include:

• Quit smoking.

• Maintain an ideal weight.

• Manage blood sugar levels and follow diabetes treatment as prescribed.

• Monitor blood pressure and treat high levels as directed.

• Avoid alcohol and caffeine.

• Avoid illicit drugs, such as cocaine and amphetamines.

• Engage in physical activity as recommended by your doctor.

• Aim for 8 to 9 hours of sleep per night.

Ongoing follow-up with a cardiologist is important. Dietary changes, such as reducing fat, sugar, and salt intake, may also be recommended.