This series of three ECGs is from a 75-year-old woman who came to the Emergency Dept. with chest pain.  The first ECG shows ST elevation in V1, V2, and V3, with generally low voltage in the QRS complexes. There is some coving upward of the ST segment in aVR, which can suggest a very proximal lesion of the left coronary artery (LCA).  She was taken to the cath lab, where it was discovered that she had a 100% occlusion of the midportion of the anterior descending branch of the left coronary artery, which was repaired and stented.  The second ECG, taken after the angioplasty, shows some Q waves in V1 and V2, with poor R wave progression in the V leads.   A 25% occlusion of the obtuse marginal branch of the circumflex artery was stented two days later. The third ECG was obtained after that procedure.  It shows that the Q waves have disappeared in the anterior leads (possibly due to different technicians performing the ECGs with different lead placement).  It also shows marked T wave inversion in I and aVL, representing ischemia in the lateral wall, and in all the chest leads, representing ischemia in the anterior wall.  The QTc is prolonged in this third ECG at 479 ms.  It is not known what medications the patient was on.  This patient also had a 50% proximal occlusion in the RCA and a 75% occlusion in the posterior descending artery.   This is a good example of a patient with extensive coronary artery disease who finally presented for treatment when she developed ST elevation M.I.  

This ECG was obtained from an elderly man who was complaining of acute-onset chest pain, radiating down his left arm.  He also complained of a cough, and had audible rhonchi.  The machine interpretation gives several possible explanations for the widespread ST elevation noted on the ECG.  The paramedics were a bit distracted by the machine's interpretation, and by the respiratory symptoms, and decided not to call a "cardiac alert" on the patient.  They did, however, quickly transport him to the closest hospital, which happened to have full-service cardiac facilities.  The patient was diagnosed with an acute M.I. and treated with angioplasty in the cath lab, with a good outcome.  Afterward, the medics felt that they "overthought" this one, and should have given more weight to the patient's symptoms.  Teach your students to evaluate their experiences with open minds and unafraid of self-criticism, so they may learn from every patient.  This patient received excellent care, and the paramedics added to their "information banks", upon which they will draw for many years to come. 

Although the angiogram results are not available to us, it is plausible that a proximal occlusion of the LCA, near the bifurcation of the LAD and the diagonal, could cause ST elevation in V3 through V6, with mild elevation in Lead II (which is oriented to the leftward portion of the inferior wall), and ST and T changes in the high lateral leads (I and aVL). 

This is a good example of acute anterior wall M.I., with ST elevation in V1 through V6, as well as in Leads I and aVL.  The extensive distribution of ST segment elevations across the anterior and high lateral walls indicates a proximal LAD artery occlusion.  In addition, this ECG shows right bundle branch block, with a QRS width of 144 ms (.14 sec.) and an rsR' pattern in V1. There is also a wide s wave in Lead I which is partly obscurred in V6 by the ST elevation.  The right axis deviation (98 degrees) suggests a left posterior fascicular block which, when coupled with the RBBB, is a bi-fascicular block.  P waves are difficult to see.  Do you think they are found at the end of the QRS complexes, representing a long first-degree AVB?  Look at leads V3 through V6 for clues.

Please feel free to add your comments below.  The more "gurus" the better.

A good ECG to teach your students that a patient facing a life-threatening emergency may have a "normal" rate and regular rhythm.  There is something in this ECG for beginners through advanced students.

This is a good ECG for demonstrating the voltage and ST criteria for LVH and acute anterior wall M.I. in the same patient, where both conditions have been confirmed by other tests.   If you are teaching the topics of ST elevation M.I., or left ventricular hypertrophy, you will probably have to address the issue that LVH can be considered a "mimic" for STEMI, especially for beginners.  This is because LVH causes ST depression in leads with upright QRS complexes, and reciprocal ST elevation in leads with negative QRS complexes.  This is called ST segment discordance.  The ST changes in LVH are due to the "strain" pattern, indicating strain on the left ventricular myocardium.  It is true that some ST elevation will appear in V1 and V2 in these patients, and can be mistaken for M.I.  In the ECG shown here, the patient has definite ST elevation in leads which would NORMALLY have depression in the LVH strain pattern.  Leads V1 through V4 have ST elevation that is not discordant, and is definitely real.  This patient was taken to the cath lab, and his left anterior descending artery stented.