Left atrial enlargement electrocardiogram
| Left atrial enlargement electrocardiogram | ||
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| eMedicine | med/ | |
| MeSH | [1] | |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]; Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [3]
Overview
Left atrial enlargement may be observed among patients with pressure or volume overload of the left atrium.
Differential Diagnosis of Left Atrial Enlargement
- Atrial aneurysm
- Infective endocarditis
- Left heart failure
- Mitral regurgitation
- Mitral stenosis
- Mitral valve prolapse
- Myxedema
- Patent Ductus Arteriosus
- Ventricular septal defect
EKG in Left Atrial Enlargement
1. LA enlargement: Left atrial enlargement produces a broad, bifid P wave in lead II (P mitrale) and enlarges the terminal negative portion of the P wave in VI.
In lead I and/or II following may be seen:
In lead V1, the following may be seen:
- Biphasic P wave with terminal negative portion > 40 ms duration (>0.04 sec or 1 small square)
- Biphasic P wave with terminal negative portion > 1mm deep
Examples of Left Atrial Enlargement on EKG
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Left atrial enlargement -
12 lead EKG: Left atrial enlargement
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Left atrial enlargement as seen in lead V1. -
Left atrial enlargement, a 12 lead ECG
