AKA: Left Atrial Enlargement (LAE), Left atrial hypertrophy (LAH), left atrial abnormality.
Left Atrial Enlargement
- Left atrial enlargement (LAE) is due to pressure or volume overload of the left atrium.
- It is often a precursor to atrial fibrillation.
ECG Criteria for Left Atrial Enlargement
LAE produces a broad, bifid P wave in lead II (P mitrale) and enlarges the terminal negative portion of the P wave in V1.
In lead II
- Bifid P wave with > 40 ms between the two peaks
- Total P wave duration > 110 ms
- Biphasic P wave with terminal negative portion > 40 ms duration
- Biphasic P wave with terminal negative portion > 1mm deep
- Classically seen with mitral stenosis
In association with left ventricular hypertrophy:
- Systemic hypertension
- Aortic stenosis
- Mitral incompetence
- Hypertrophic cardiomyopathy
- Brady WJ, Truwit JD. Critical Decisions in Emergency and Acute Care Electrocardiography
- Hampton, JR. The ECG In Practice, 6e
- Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric, 6e
- Wagner, GS. Marriott’s Practical Electrocardiography 12e
- Chan, TC. ECG in Emergency Medicine and Acute Care
- Mattu, A. ECG’s for the Emergency Physician
LITFL Further Reading
- ECG BASICS — Waves, Intervals, Segments and Clinical Interpretation
- ECG A to Z by diagnosis –alphabetical diagnostic approach to the ECG
- ECG CLINICAL CASES — ECG’s placed in clinical context with a challenging Q&A approach
- 100 ECG Quiz — Self-assessment tool for examination practice
- ECG Reference SITES and BOOKS — the best of the rest
- LITFL ECG IMAGE Database — Searchable database of LITFL ECG’s
- ECG and Cardiology Eponymous Syndromes — Cheats guide to eponymous emancipation
- ECG Exam Template — a framework for answering ECG exam questions.