Cardiomegaly
Cardiomegaly is a catch-all term to refer to enlargement of the heart, and should not be confused with causes of enlargement of the cardiomediastinal outline, or enlargement of the cardiac silhouette.
On this page:
Pathology
Etiology
There are many etiologies for cardiomegaly:
- congestive heart failure
- ischemic heart disease
- hypertension (with left ventricular hypertrophy)
- valvular disease
-
cardiomyopathy
- idiopathic cardiomyopathy
- alcoholic cardiomyopathy
- hypertrophic cardiomyopathy
- drugs (numerous drugs are cardiotoxic)
- congenital heart disorders
- pulmonary disease (leading to right-sided enlargement)
- myocarditis
- systemic disease/physiology
- normal “athletic” heart
- pregnancy
- renal failure
- anemia
- scleroderma
- systemic lupus erythematosus
- sickle cell disease
- rheumatoid arthritis
- Marfan syndrome
- post-radiation
Radiographic features
Although in most cases merely 'eye-balling' a chest x-ray will be sufficient in detecting cardiomegaly (as in most cases the heart is either clearly normal in size or clearly abnormally enlarged) when unsure the cardiothoracic ratio can be measured.
Specific cardiac chamber enlargement can be recognised by cardiac contour changes, new or different interfaces with adjacent lung, and/or displacement of adjacent mediastinal structures. These are discussed separately:
- right atrial enlargement
- right ventricular enlargement
- left atrial enlargement
- left ventricular enlargement
Differential diagnosis
- other causes of an enlarged cardiac silhouette