Inverted P wave

Jump to: navigation, search

WikiDoc Resources for Inverted P wave


Most recent articles on Inverted P wave

Most cited articles on Inverted P wave

Review articles on Inverted P wave

Articles on Inverted P wave in N Eng J Med, Lancet, BMJ


Powerpoint slides on Inverted P wave

Images of Inverted P wave

Photos of Inverted P wave

Podcasts & MP3s on Inverted P wave

Videos on Inverted P wave

Evidence Based Medicine

Cochrane Collaboration on Inverted P wave

Bandolier on Inverted P wave

TRIP on Inverted P wave

Clinical Trials

Ongoing Trials on Inverted P wave at Clinical

Trial results on Inverted P wave

Clinical Trials on Inverted P wave at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Inverted P wave

NICE Guidance on Inverted P wave


FDA on Inverted P wave

CDC on Inverted P wave


Books on Inverted P wave


Inverted P wave in the news

Be alerted to news on Inverted P wave

News trends on Inverted P wave


Blogs on Inverted P wave


Definitions of Inverted P wave

Patient Resources / Community

Patient resources on Inverted P wave

Discussion groups on Inverted P wave

Patient Handouts on Inverted P wave

Directions to Hospitals Treating Inverted P wave

Risk calculators and risk factors for Inverted P wave

Healthcare Provider Resources

Symptoms of Inverted P wave

Causes & Risk Factors for Inverted P wave

Diagnostic studies for Inverted P wave

Treatment of Inverted P wave

Continuing Medical Education (CME)

CME Programs on Inverted P wave


Inverted P wave en Espanol

Inverted P wave en Francais


Inverted P wave in the Marketplace

Patents on Inverted P wave

Experimental / Informatics

List of terms related to Inverted P wave

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ayokunle Olubaniyi, M.B,B.S [2]


Ordinarily, an impulse traveling from a point high in the atrium to the ventricle is right side up on the electrocardiographic tracing, but if this pacemaker impulse originates in lower part of the atrium, the orientation of the electrical vector may cause it to appear upside down or to be an "inverted P-wave".


Inverted P waves can be classified into two based on the leads affected. They are:

Those Causing Inverted P waves in Leads I and aVL

  • Dextrocardia
  • Misplacement of leads a.k.a technical dextrocardia

Those Causing Inverted P waves in Leads II, III, and aVF (inferior leads)

This involves all the conditions which cause a retrograde atrial activation i.e. an upward flow of electrical currents from an ectopic focus in the lower atrium or AV node. They include:


During the normal atrial depolarization, the electrical impulse originates from the SA node in the right atrium and flows downwards through the right and left atrial muscle to the AV node (right to left depolarization). This movement of electrical current points towards the positive pole of lead II and the negative pole of lead aVR. Therefore, the normal sinus P wave is positive (upright) in lead II and negative (inverted) in lead aVR. However, when the flow of electrical current is from an ectopic focus either in the lower part of the atrium or in the AV junction, the current moves in the upward direction from the left to the right (left to right depolarization), consequently, leading to a reversal of the normal i.e. negative P wave in lead II and positive in aVR. The abnormalities in the morphology of P waves are best evaluated in the inferior leads of the EKG - leads II, III, and aVF.


This is a condition in which the heart is situated on the right side. Therefore, the flow of electrical impulse originates from the left side and terminates on the right (a reversal of the normal). The resultant effect on EKG include:

  • Right axis deviation
  • Positive QRS complexes (with upright P and T waves) in aVR
  • Lead I: inversion of all complexes, aka ‘global negativity’ (inverted P wave, negative QRS, inverted T wave)
  • Absent R-wave progression in the chest leads (V1-V6)
EKG in a patient with dextrocardia

Misplacement of Leads

This refers to the inadvertent misplacement of limb or precordial leads which results into an abnormal P wave, QRS, and abnormal R wave progression. However, in contrast to dextrocardia there is normal R wave progression in the chest leads. Typical features include:

  • Inversion of lead I
  • Reversal of Leads aVR and aVL
  • Reversal of Leads II and III

Retrograde Atrial Activation

This occurs when there is a conduction of cardiac impulse from the ventricular to atrial direction. The origin of the electrical impulses could either be from: