Cardiomegaly: Definition, Causes, and Clinical Significance

Cardiomegaly is the medical term for an enlarged heart. It is not a disease itself but a sign of an underlying condition that increases cardiac workload or damages heart muscle.

Common Causes

• Hypertension (chronic pressure overload → left ventricular hypertrophy)
• Coronary artery disease / prior myocardial infarction (remodelling, dilation)
• Valvular heart disease (volume or pressure overload)
• Cardiomyopathies (dilated, hypertrophic, restrictive)
• Pericardial effusion (fluid around the heart mimics enlargement on imaging)
• Congenital heart disease
• Pulmonary hypertension (right ventricular enlargement)
• Anaemia, thyroid disease, amyloidosis

Symptoms (when present)

• Dyspnoea (especially on exertion or lying flat)
• Fatigue, exercise intolerance
• Palpitations, arrhythmias
• Peripheral oedema
• Chest discomfort

Diagnosis and Management

Detected via chest X-ray, echocardiogram, cardiac MRI, or CT. Treatment targets the underlying cause: blood pressure control, revascularization, valve repair/replacement, guideline-directed medical therapy for heart failure, etc. Prognosis depends on aetiology and timeliness of intervention.