II. Definitions
- P Wave
- Electrical signal on EKG representing depolarization (and contraction) of the atria
- Start of the P Wave represents right atrial depolarization, and the end of the P Wave represents left atrial depolarization
III. Findings: Normal
- Upright and Monophasic: I, II, V3, V4, V5, V6
- Inverted: aVR
- Variable: III, avL, avF, V1, V2, V3
IV. Causes: P Wave Inversion in leads I, II, V3-V6 (narrow complex with normal ventricular rate)
- Ectopic atrial focus
- Junctional Rhythm (AV Nodal or proximal purkinje) with retrograde P Waves preceding the QRS
V. Causes: High Amplitude - Atrial hypertrophy or atrial dilatation
- Mitral valve or tricuspid valve disease
- Hypertension
- Cor Pulmonale
- Congenital Heart Disease
VI. Causes: Low Amplitude (short P Wave)
- Hyperkalemia (associated with a Tall T Wave)
VII. Causes: Wide P Wave (width >0.11 sec)
- Left atrial enlargement
VIII. Causes: Biphasic P Wave (second half negative in III or V1)
- Left Atrial Enlargement
IX. Causes: M shaped or notched P Wave
- M-Mitral or P-Mitrale: Left atrial enlargement
- Findings
- Over 0.04 seconds between peaks
- Taller in I than in III
X. Causes: Peaked P Wave
- P-Pulmonale: Right atrial enlargement
- Findings
- Tall and pointed P Wave >2.5 mm in the inferior leads
- P Wave is taller in Lead III than in I
XI. Causes: P Waves absent
- Precaution
- Look closely for regularly spaced "artifact" on the ekg (e.g. low voltage P Waves)
- Atrial Fibrillation or Atrial Flutter
- Sinoatrial Node block
- AV Nodal Rhythm
XII. References
- Berberian (2023) Crit Dec Emerg Med 37(5): 12-3
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Related Studies
| Definition (NCI_CDISC) | An electrocardiographic finding suggesting underlying hypertrophy or dilatation of the right atrium. Electrocardiographic criteria used for the diagnosis of right atrial abnormality may include a peaked p wave greater than 2.5 millimeters in amplitude in the inferior leads. (NCI) |
| Definition (NCI) | An electrocardiographic finding suggesting underlying hypertrophy or dilatation of the right atrium. Electrocardiographic criteria used for the diagnosis of right atrial abnormality may include a peaked p wave greater than 2.5 millimeters in amplitude in the inferior leads. |
| Concepts | Finding (T033) |
| SnomedCT | 142074002, 1692000, 164914003 |
| Dutch | elektrocardiogram P pulmonale |
| French | Coeur pulmonaire à l'électrocardiogramme |
| Italian | Onda P polmonare dell'elettrocardiogramma |
| Portuguese | Electrocardiograma P pulmonale |
| Spanish | P pulmonar en el electrocardiograma, P pulmonar (hallazgo), P pulmonar, signos electrocardiográficos de P pulmonar (hallazgo), signos electrocardiográficos de P pulmonar |
| Japanese | 心電図肺性Ｐ波, ｼﾝﾃﾞﾝｽﾞﾊｲｾｲPﾊ |
| English | P pulmonale by EKG (finding), p pulmonale, Right Atrial Enlargement by ECG Finding, P pulmonale by electrocardiogram (finding), P pulmonale by electrocardiogram, P pulmonale by EKG, P-pulmonale by EKG Finding, Right Atrial Enlargement, P-pulmonale by ECG Finding, RIGHT ATRIAL ABNORMALITY, P-pulmonale, P pulmonale, P pulmonale (finding), Electrocardiogram P pulmonale |
| Czech | Elektrokardiogram P pulmonale |
| Hungarian | Elektrokardiogram P pulmonale |
| German | Elekrokardiogramm P pulmonale |
Ontology: P mitrale (finding) (C0232310)
| Definition (NCI) | An electrocardiographic finding suggesting underlying hypertrophy or dilatation of the left atrium. Electrocardiographic criteria used for the diagnosis of left atrial abnormality may include a bifid p wave, a biphasic p wave and/or a p wave duration of greater than 0.12 seconds. |
| Definition (NCI_CDISC) | An electrocardiographic finding suggesting underlying hypertrophy or dilatation of the left atrium. Electrocardiographic criteria used for the diagnosis of left atrial abnormality may include a bifid p wave, a biphasic p wave and/or a p wave duration of greater than 0.12 seconds. (NCI) |
| Concepts | Finding (T033) |
| SnomedCT | 142073008, 4725002, 164913009 |
| English | P mitrale (finding), Left Atrial Enlargement by ECG Finding, P mitrale by electrocardiogram, P mitrale by EKG, P mitrale by EKG (finding), P mitrale by electrocardiogram (finding), Left Atrial Enlargement, P-mitrale by ECG Finding, P-mitrale by EKG Finding, P-mitrale, LEFT ATRIAL ABNORMALITY, P mitrale |
| Spanish | P mitral (hallazgo), P mitral, signos electrocardiográficos de P mitral (hallazgo), signos electrocardiográficos de P mitral |
Ontology: P wave feature (C0429084)
| Definition (NCI) | An electrocardiographic finding of the current of atrial contraction when they are depolarized. The 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 | Organism Attribute (T032) |
| SnomedCT | 142070006, 33405001 |
| LNC | MTHU024602 |
| English | p wave, p waves, P Wave, P wave (observable entity), P wave, P wave feature (observable entity), P wave feature |
| Spanish | onda P (entidad observable), onda P |
