Low ECG voltage

Background

General Causes

• Fluid, fat or air attenuating signal
• Myocardial infiltration
• Loss of viable myocardium

Clinical Features

• Frequently asymptomatic, depends on underlying cause

Differential Diagnosis

Specific causes of low voltage ECG

Low ECG voltage

Cardiac

• Post-MI
• Infiltrative cardiomyopathy
• Myocarditis
• Hypothyroidism

Pericardial

• Effusion
• Constrictive pericarditis
• Pneumopericardium

Extracardiac

• COPD (limb leads)
• Pneumomediastinum
• Pneumothorax
• Pleural effusion
• Pulmonary edema
• Peripheral edema
• Obesity

Evaluation

Sample ECG

• ECG
  • QRS < 5 mm in limb leads
  • QRS < 10 mm in chest leads

Management

• Treat underlying condition

Disposition

• Depends on underlying condition

See Also

• ECG Basics

External Links

• DDxOf: Differential Diagnosis of Low Voltage ECG