ECG Criteria of Right Atrial Enlargement

Right atrial enlargement produces a peaked P wave (P pulmonale) with amplitude:

• > 2.5 mm in the inferior leads (II, III and AVF)
• > 1.5 mm in V1 and V2

Also known as: Right Atrial Enlargement (RAE), Right atrial hypertrophy (RAH), right atrial abnormality

P wave changes with Right Atrial Enlargement

Causes of Right Atrial Enlargement

The principal cause is pulmonary hypertension due to:

• Chronic lung disease (cor pulmonale)
• Tricuspid stenosis
• Congenital heart disease (pulmonary stenosis, Tetralogy of Fallot)
• Primary pulmonary hypertension

ECG Examples

Example 1

• Right atrial enlargement: P pulmonale
• P wave amplitude > 2.5mm in leads II, III and aVF

Example 2

• Right atrial enlargement: P wave amplitude > 1.5 mm in V1 and V2

Related Topics

• The P Wave
• Left Atrial Enlargement
• Biatrial Enlargement

References

• Harrigan RA, Jones K. ABC of clinical electrocardiography. Conditions affecting the right side of the heart. BMJ. 2002 May 18;324(7347):1201-4. PMID: 12016190
• Chung DC, Nelson HM. ECG – A Pictorial Primer [internet]
  

LITFL Further Reading

• ECG Library Basics – Waves, Intervals, Segments and Clinical Interpretation
• ECG A to Z by diagnosis – ECG interpretation in clinical context
• ECG Exigency and Cardiovascular Curveball – ECG Clinical Cases
• 100 ECG Quiz – Self-assessment tool for examination practice
• ECG Reference SITES and BOOKS – the best of the rest

Advanced Reading

• Brady WJ, Truwit JD. Critical Decisions in Emergency and Acute Care Electrocardiography
• Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric
• Wagner GS. Marriott’s Practical Electrocardiography 12e
• Chan TC. ECG in Emergency Medicine and Acute Care
• Rawshani A. Clinical ECG Interpretation
• Mattu A. ECG’s for the Emergency Physician
• Hampton JR. The ECG In Practice, 6e