http://www.fpnotebook.com/
P Wave
- Findings: Normal
- Upright: I, II, avF, V4, V5, V6
- Inverted: aVR
- Variable: III, avL, V1, V2, V3
- Causes: P Wave Inversion (other than aVR)
- Ectopic atrial focus
- AV nodal rhythm
- Causes: High Amplitude: Atrial hypertrophy or atrial dilatation
- Mitral valve or tricuspid valve disease
- Hypertension
- Cor Pulmonale
- Congenital Heart Disease
- Causes: Wide P Wave (over .11 sec)
- Left atrial enlargement
- Causes: Biphasic P Wave (second half negative in III or V1)
- Left Atrial Enlargement
- Causes: M shaped or notched P Wave
- M-Mitral: Left atrial enlargement
- Findings
- Over 0.04 seconds between peaks
- Taller in I than in III
- Causes: Peaked P Wave
- P-Pulmonale: Right atrial enlargement
- Findings
- Tall and pointed
- Taller in Lead III than in I
- Causes: P Waves absent
- Sinoatrial node block
- AV Nodal rhythm
P wave feature (C0429084) | |
|---|---|
| Definition (NCI) | P wave is the electrical signature of the current that causes atrial contraction - the portion of the EKG tracing that represents depolarization of the atrial myocardium. Initial portion of the P wave is largely a reflection of right atrial depolarization and the terminal portion reflects depolarization of the left atrium. |
| Concepts | Finding (T033) |
| English | EKG P Wave, P wave, P wave feature |
| Spanish | onda P |
| Parent Concepts | EKG Concept (C1880437), ECG waveform (C0428732), Duplicate concept (C1274013) |
| Sources | LNC, NCI, SCTSPA, SNOMEDCT Derived from the NIH UMLS (Unified Medical Language System) |
