Pages

Thursday, February 13, 2014

The Power of the 12th Lead
EMS responds to the home of a 70 yo female patient. She reports severe, left-sided chest pain and mild shortness of breath.  Her skin is warm and dry.  Her abdomen is soft and non-tender.  She denies any medical history.

Vital signs:
BP: 142/76
P: 75
R: 18
Sp02: 98%

12 Lead ECG:


12 Lead ECG Interpretation and Discussion:
There is a baseline sinus rhythm. The rate is approximately 75 beats per minute.

The ECG also reveals left anterior fascicle block as noted by the rS pattern in leads II, III, aVF, and Rs pattern in leads I and aVL.

There is left axis deviation as demonstrated by the predominantly positive QRS complex in lead I, and predominantly negative QRS complex in lead aVF.

There is ST segment elevation in leads aVR and V1. In addition, ST segment changes (flat, depressed, or T wave inversion) are present in essentially every other lead (reciprocal changes).  Simultaneous ST segment elevation in leads aVR and V1 may predict left main coronary artery, or left anterior descending artery occlusion, and is considered to be a STEMI equivalent.  Patients who present with ST segment elevation in leads aVR and V1 should be transported to a facility capable of performing cardiac angioplasty.

Take-Home Points
Simultaneous ST segment elevation in leads aVR and V1 predicts LMCA or LAD occlusion
Patients should be transported to a cardiac intervention center and treated the same as STEMI



1 comment:

  1. What makes this ECG ischemic? What if you're not reading the latest buzz about aVR? Feel a little lonely when the "ECG...data prevents interpretation?"
    1. ST depression and T wave inversion is present in the inferior leads. Reciprocal change suggests ischemia
    2. Widespread and ugly-looking ST depression and T wave inversion is also present in the precordial leads
    3. There is probably a component of LVH present in this ECG as shown in leads V4-V6- this may be responsible for additional changes in the ST segment
    4. As always, patient age and history trump equivocal ECG findings. If a 70 year old patient presents to EMS with chest pain and shortness of breath, its important to keep ACS/MI at the top of your field impression.
    5. Take the time to get a good tracing. Ensure the patient's skin is clean and dry. Try minimize respiratory or motion artifact.

    ReplyDelete