Cardiomegaly

Any factor that forces the heart to work harder than normal can result in an enlarged heart, a condition known as cardiomegaly. Cardiomegaly — an enlarged heart — is not a distinct disorder but a symptom of an underlying disease, most often a cardiac condition. Now, you might think that a bigger heart means a stronger one, but that’s not necessarily true. In fact, when the heart grows larger due to strain, it often becomes weaker instead of stronger.

A lot of different conditions can cause this, but one of the most common culprits is coronary artery disease (CAD). When the arteries supplying the heart get clogged, the heart has to pump harder to get blood where it needs to go. Over time, this extra effort can lead to enlargement.

But CAD isn’t the only reason a heart might enlarge. Other possible causes include:

Cardiomyopathy (autoimmune, congenital, alcohol- or drug-induced).
Hypertension.
Myocarditis.
Anemia.
Pregnancy.
Sarcoidosis.
Arrhythmias.
Kidney failure.
Valvular heart disease.
Hyperthyroidism or hypothyroidism (thyroid disorder).
Pulmonary disease (chronic obstructive pulmonary disease, hypertension, embolism).



The risk factors include the usual culprit heavy alcohol consumption, family history, substance abuse, history of Myocardial infarction or cardiomyopathy or even sedentary lifestyle.

Cardiomegaly usually isn’t suspected and diagnosed until symptoms start showing up. To confirm it, doctors rely on imaging tests. The first step is usually a chest X-ray, and if needed, they follow up with an electrocardiogram (ECG) to get a clearer picture. Imaging studies are required to diagnose cardiomegaly. When cardiomegaly is suspected, the first imaging test typically performed is chest radiography, followed by an electrocardiogram (ECG)

An ECG can give clues about an enlarged heart, like thickened heart walls (ventricular hypertrophy), which is common in conditions like high blood pressure or heart valve disease. It can also detect signs of a past heart attack or irregular heartbeats.

For a more detailed look, a transthoracic echocardiogram helps measure heart chamber size and checks how well the heart is functioning, including its movement and valve health.

If even more detail is needed, cardiac MRI or CT scans provide a clearer picture of the heart’s size, blood vessels, and surrounding structures.

Since coronary artery disease (CAD) is a common cause of an enlarged heart, a stress test—either exercise-based or medication-induced—might be recommended, especially for those with risk factors for CAD. Blood testing can also help identify and assess possible underlying causes. The findings from the following blood tests are used to evaluate patients for heart disease:

Cardiac enzymes.
Complete blood count.
Complete metabolic panel.
Thyroid function tests.
Lipid profile.
Liver tests.
Coagulation tests.
B-type natriuretic peptide and
Blood glucose.

Cardiomegaly Treatments
The best way to treat an enlarged heart really depends on what’s causing it and how far it has progressed. Treatment might involve lifestyle changes, medications, and, in some cases, surgery.

Some key lifestyle adjustments can help manage or even prevent heart problems, including: ✅ Avoiding alcohol and tobacco

✅ Eating a heart-healthy diet

✅ Keeping cholesterol levels in check

✅ Maintaining a healthy weight

✅ Managing diabetes

✅ Staying active with regular exercise

✅ Reducing stress

✅ Getting enough sleep

For those with high blood pressure, medications like ACE inhibitors, calcium channel blockers, diuretics, and ARBs-angiotensin receptor blockers are often the go-to options.

References

Heidenreich PA, Bozkurt B, Aguilar D, et al; ACC/AHA Joint Committee Members. 2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2022;145(18): e895-e1032. doi:10.1161/CIR.0000000000001063\
Carey RM, Moran AE, Whelton PK. Treatment of hypertension: A review. JAMA. 2022;328(18):1849-1861. doi:10.1001/jama.2022.19590
Enlarged heart. Heart and Stroke Foundation of Canada. Accessed February 13, 2025. https://www.heartandstroke.ca/heart-disease/conditions/enlarged-heart