What is an Enlarged Heart?

An enlarged heart or cardiomegaly is not a disease but a symptom of various conditions and is treatable by addressing the underlying issue. Enlargement occurs when the heart chambers become dilated or the walls thicken abnormally. A slightly bigger-than-average heart can still function normally, but if cardiomegaly progresses, the heart’s ability to pump blood declines. Most often, doctors discover cardiomegaly through routine chest x-rays.

Symptoms of an Enlarged Heart

In its early and moderate stages, an enlarged heart is often asymptomatic, meaning it does not cause noticeable symptoms. Once it becomes difficult for the organ to pump blood, signs of congestive heart failure usually emerge. These may include:

  • Intense heart palpitations (episodes of irregular heartbeat that come and go)
  • Shortness of breath, especially during physical activity
  • Chest pain
  • Leg swelling (edema)
  • Tiredness or fatigue
  • Increased abdominal size due to edema or fat accumulation
  • Fainting spells or extreme dizziness

Shortness of breath may be so severe it feels similar to an asthma attack, and chest pain often worsens when accompanied by breathing difficulties.

Causes of an Enlarged Heart

Common causes of an enlarged heart include high blood pressure, coronary artery disease (CAD), a previous heart attack, heart valve problems, and inheritance of cardiomegaly genes. CAD may block the blood supply to the heart and promote a heart attack (cardiac infarction). An enlarged heart may also be the result of heart muscle disease (cardiomyopathy), thyroid disorders, pulmonary hypertension, fluid around the heart (pericardial effusion), alcohol abuse, diabetes, HIV, or advanced kidney disease.

Two Types of Cardiomegaly

Doctors diagnose patients with either dilated cardiomyopathy or hypertrophic cardiomyopathy. The former is the most common type and involves the thinning or stretching of one or both of the heart’s ventricles. Hypertrophic cardiomyopathy, when the left ventricle thickens and enlarges, is often inherited and may be present at birth.

Diagnosing an Enlarged Heart

Chest x-rays and electrocardiograms are common in diagnosing an enlarged heart. A chest x-ray allows doctors to evaluate the cardio-thoracic ratio to determine if the heart is too large. Recording the organ’s electrical activity via electrocardiogram testing detects problems with rhythm and determines whether damage to heart muscles has occurred from “silent” heart attacks. Echocardiograms monitor sound waves produced by a beating heart and assess the condition of the four chambers. In some cases, doctors may also want to do a cardiac catheterization to obtain a sample of the heart’s tissues to look for signs of infection, inflammation, or abnormal cells. This information may help determine the cause of an enlarged heart.

Treatment for an Enlarged Heart

Many medications can treat an enlarged heart, including diuretics to lower water and sodium levels and relieve pressure, anticoagulants to minimize the risk of blood clots, blood pressure medications, and antiarrhythmics to regulate heartbeat. Physicians may prescribe one or more of these, depending on the related complications.

More Treatments for an Enlarged Heart

Pacemakers and implantable cardioverter defibrillators (ICDs) coordinate contractions between the right and left ventricles. Patients with serious arrhythmias may need one of these devices to maintain a normal heartbeat. In advanced cases of cardiomegaly, surgical procedures such as heart valve or coronary bypass surgery can prevent heart failure. When an enlarged heart does not respond to less-invasive treatments, a heart transplant is a final option.

Complications of Cardiomegaly

While an enlarged heart is nearly always treatable, complications may arise if the individual does not take medications as prescribed or has not made lifestyle changes essential for supporting heart health. Heart failure is the most serious complication, followed by blood clots and sudden death. Cardiomegaly facilitates the formation of blood clots in the heart’s lining. If just one clot becomes dislodged and enters the bloodstream, it could travel to a vital organ and cause a stroke or heart attack. Heart murmurs may occur if the heart’s valves do not close properly; the noise is the sound of blood flowing back into the heart.

Risk Factors for an Enlarged Heart

The following factors can raise one’s risk of cardiomegaly: high blood pressure, family history of cardiomyopathy, coronary artery disease, congenital heart disease, heart valve disease, history of heart attack, a viral infection of the heart, alcohol abuse, recurring heart infections, and vitamin deficiencies.

Reducing Risk of Developing an Enlarged Heart

Although infections and heredity are uncontrollable, other factors that raise one’s risk of cardiomegaly can be mitigated and the risk reduced. Everyone can benefit from these preventative measures, though they are most important for people already at high risk. Try to limit salt intake, eat healthy foods, and exercise regularly. Get enough sleep every night to minimize stress, and take prescribed medications as instructed. People with hypertension should regularly monitor their blood pressure. Cardiomegaly affects people of all ages, although it’s more common in older men and women.

The prognosis for an Enlarged Heart

Most people with an enlarged heart who take their medications and make necessary lifestyle changes lead normal lives. Cardiomegaly typically stabilizes and may even improve following diagnosis and treatment. People with enlarged hearts should report any unusual or worsening symptoms to their doctor as soon as they develop.