This 66-year-old man presented with a complaint of chest pain. His ECG shows a "classic" inferior wall ST-elevation M.I. (STEMI). The ST elevation is apparent in Leads II, III, and aVF, which are the leads that reflect the inferior wall of the left ventricle. In addition, this ECG shows ST elevation in Leads V5 and V6, the low lateral wall. The ST depression in V1 and V2 are reciprocal changes caused by acute injury in the posterior wall. In the majority, the RCA supplies the inferior-posterior wall, the right ventricle, the right atrium (including the SA node and the AV node), and in some, the low lateral wall. The proximal location of this man's occlusive lesion has caused damage in all these areas. The relatively slow rate is common in IWMI and can be caused by SA node injury, vagal stimulation, or medications. Clinical data is not available for this patient.
This ECG is from old files, and no patient information is available. Acute ST elevation is apparent in lateral leads I and aVL, and in Lead II. In addition, the anterior leads V1, V2, and V3 show reciprocal ST depression and, in V1 and V2, taller-than-normal R waves. This points to acute posterior - lateral M.I., probably due to occlusion of the circumflex artery. Unfortunately, we do not have angiogram confirmation for this.
The P waves are interesting. They are hard to see because of their small size and the fine baseline artifact present. The best view appears to be in the Lead II rhythm strip at the bottom. In this view, the P waves' morphology appears to be changing. What do you think?
This ECG was taken from a 66-year-old woman who presented to the emergency department complaining of chest pain and shortness of breath. She attributed her symptoms to her COPD, but stated that her aerosol treatment had not helped. She waited for some time before deciding to go to the hospital, then drove herself. In the emergency department, she had blood drawn, an I.V. started, and an aerosol treatment of albuterol. She was then taken to the radiology dept. for a chest xray. When she returned, a 12-lead ECG was done. 45 minutes had passed since she first arrived at the hospital. This ECG is shown here. It shows ST elevation in the inferior leads: II, III, and aVF. The patient was taken immediately to the cath lab, where her right coronary artery was found to have a 100% occlusion. (See image accompanying this ECG). Angioplasty was successful, and stents were placed in the artery. The patient was found to have anemia, with a hemoglobin of 5.5, and she was given a blood transfusion. During the cath procedure, a ventriculogram was performed, which showed a stunned and akinetic inferior wall. Unfortunately, subsequent ventriculogram performed several weeks later showed the lack of motion of the inferior wall to be permanent. The ventriculogram is also posted here, and at this YouTube link, so you will be able to show your students the mechanical effects on the heart of a delay to treatment in acute STEMI. See our YouTube site for more ventriculograms and cath videos.
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 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.
This week's ECG of the Week is from an elderly woman who suffered an acute occlusion of the right coronary artery. The ECG clearly shows ST elevation in leads II, III, and aVF, indicating inferior wall injury. In this case, this ECG was obtained in the field by paramedics, and was the second ECG done on this patient. For this tracing, the paramedics obtained V3 and V4 on the right side to better view the right ventricle. V3 and V4 right clearly show ST elevation as well, indicating RVMI. The slight coving and elevation observable in V1 is also an indication of RV involvement, and the ST depression in V2 indicates posterior wall injury. All of this results from a proximal lesion of the RCA in this patient. Such a lesion carries a high morbidity and mortality.
Taking the time to obtain a right ventricular lead is controversial in some settings. Some believe the patient's hemodynamic condition should be treated, regardless of the presence or absence of ST elevation in right chest leads. Others find it very helpful to know that the right ventricle is affected. In this case, paramedics in this community have a protocol to avoid the use of nitroglycerine in RVMI patients, even when the BP is adequate. So, for them, it is important to have the information gathered from V Right leads.
The rhythm here is interesting, as well, and not at all uncommon for IWMI patients. The baseline artifact makes it a bit difficult to march out all the P waves, but it appears they are sinus P waves that are slightly irregular at a rate of 52 to 54. The PR intervals appear to be progressively prolonging, but there is no "grouped beating" observable on this short strip. A lack of a concurrent Lead II rhythm strip also makes it difficult to determine the rhythm, as Lead II does have very visible P waves, and would be helpful. The regularity of the narrow complex bradycardia points to a junctional escape rhythm, which would make this a third-degree AVB at the AV node level, which is very common with IWMI. What do you think?
This month's strip from Jason Roediger's ECG Challenge blogpost is a nice complement to the strip presented here. His is much clearer, and has a Lead II rhythm strip. Do you think these ECGs show the same rhythm, or two different rhythms?
For an excellent discussion of "AV Dissociation" vs. "AV Block", go to Christopher Watford's Ask the Expert post. Thanks very much to ECG Guru Sebastian Garay for this interesting ECG.
This ECG was provided by Jamie Bisson, of E Advanced Healthcare.
The patient, in cardiogenic shock, was resuscitated in the Emergency Department, then sent to the cath lab, where his left main coronary artery was opened and stented.
Many people with complete occlusion of the left main do not survive. When there is some diminished blood flow through the blocked area in the proximal LAD or left main, this pattern may appear. Look for ST elevation in aVR greater than or equal to 1 mm, ST elevation in aVR greater than the ST elevation in V1, and widespread ST depression.
In this ECG, aVR and V1 show ST segment elevation, with widespread ST depression. For years, aVR was virtually ignored in the literature, and considered to be only a reciprocal view of the lateral inferior wall. Now, there is convincing evidence of its usefulness in discovering proximal left coronary artery occlusion and severe triple vessel disease. ST elevation in aVR can be a reliable sign of ischemia of the basal part of the heart and the proximal IV septum.
Many people with complete occlusion of the left main do not survive. When there is diminished blood flow through the blocked area in the proximal LAD or left main, this pattern may appear. Look for ST elevation in aVR greater than or equal to 1 mm, ST elevation in aVR greater than the ST elevation in V1, and widespread ST depression.
For complete discussions on this topic, go to Life in the Fast Lane,
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.
Unbelievably, this inferolateral ST elevation M.I. was missed by the treating paramedics in the field. An elderly woman stepped off a curb and was hit by a very slow-moving car. She fell and sustained a Colle's fracture of the right wrist. While the paramedics assessed her, she complained of chest pain, prompting them to perform a 12-Lead ECG. The machine's interpretation called attention to the inferior and lateral walls' injury pattern, but the paramedics did not believe it, because "she was a trauma patient". They ran three ECGs, and still did not agree with the machine.
The patient was transported to a hospital without an interventional cath lab, and she was forced to endure a one-hour wait to be transferred to an appropriate hospital.
This is a great ECG for a discussion with your students about "distractors". The call came in as a trauma, so that, in itself, was a distractor. The rescuers saw what they expected to see. The angulated fracture distracted them - putting them into full trauma assessment mode. Then, the frequent and coupled PVCs also distracted them, possibly making it more difficult for them to evaluate the ST segments in the normal beats. Interestingly, the second and third ECGs did not have PVCs, and the ST elevation was even more clear.
PVCs which are repeating themselves in groups of two, three, or more are sinister in a chest pain patient, and may indicate LV dysfunction. They could possibly result in ventricular tachycardia, which would be disasterous for this patient.
A good teaching ECG, showing clearly elevated ST segments in V1 through V4. This patient had an LAD occlusion. In addition, he has new-onset atrial fib at a rate of about 120/min. Atrial fib has decreased cardiac output because of the loss of P waves prior to the QRS complexes, and a resultant decreased ventricular filling pressure. In addition, this fast rate contributes to increased myocardial oxygen demand and damage. An early priority, along with getting this patient to PCI, is slowing the rate.