ECG Guru - Instructor Resources

A gathering place for instructors of ECG and cardiac topics.


Subscribe to me on YouTube

Inferior Wall ST-elevation M.I.

Dawn's picture
Sun, 02/24/2013 - 12:24 -- Dawn

This is an excellent example of acute inferior wall ST elevation M.I. (STEMI) in a 78 year old woman who had been experiencing intermittent chest pain for two days.  This 12-lead ECG has been formatted to simultaneously produce three rhythm strips below the 12-Lead.  The rhythm strips are run simultaneously with the 12-Lead, and show 3 different leads.  This feature can been invaluable when trying to decipher complex rhythms.

In this case, the patient is in normal sinus rhythm, and has classic ST segment elevation in the inferior wall leads:  II, III, and aVF.  There is some reciprocal ST depression in Leads I and aVL, and also in V1 and V2, suggesting injury extending up the posterior wall. ST depression is noticeable in V6 as well.  This patient's RCA lesion was opened and stented, and she did well immediately post cath.  We have no records past that.


Rate this content: 
Average: 5 (4 votes)

Comments's picture

GREAT example of acute inferior STEMI by Dawn from a patient who interestingly had chest pain for 2 days (!) - emphasizing the point that more than just duration of symptoms may provide indication of the need for acute reperfusion. I'll just add a few points to Dawn's description.

  • In addition to acute inferior STEMI - there is evidence of definite acute posterior involvement because: i) there is ST depression in leads V1,V2 of the type that provides a positive "mirror test"; and ii) there is rapid development of a taller-than-expected R wave by V2,V3 (which in the "mirror test" corresponds to the reciprocal of a developing Q wave).
  • We suspect acute proximal RCA (Right Coronary Artery) occlusion because: i) ST elevation in lead III is more marked than in lead II; and ii) there is marked reciprocal ST depression in lead aVL that is greater in amount than in lead I.
  • Right ventricular involvement often accompanies proximal RCA occlusion. That said - lack of ST flattening or slight elevation in lead V1 is against RV involvement. If one wanted to know for sure - then application of right-sided precordial leads could be used to clarify.
  • Despite up to 2 days of symptoms - this patient is still an excellent candidate for acute reperfusion because: i) there is marked ST elevation; ii) there is marked reciprocal ST depression (present also in leads V4,V5,V6 as well as I and aVL); and iii) No more than minimal inferior q waves have developed.

Ken Grauer, MD   [email protected] 

Submitted by Cristian on


Thank you Dawn for sharing this nice EKG and thank you Ken for adding the bright clinical light to the scene, which makes this EKG look so vivid.


All our content is FREE & COPYRIGHT FREE for non-commercial use

Please be courteous and leave any watermark or author attribution on content you reproduce.