EKG Practice #3
- Nov 21st, 2014
- Ray Fowler
By Ray Fowler, MD
Professor of EM / EMS
UTSW / Parkland
Edited by Alex Koyfman, MD
This 77 female presents with chest discomfort of several hours duration. She has a hx of stable angina, and she has not had any coronary intervention. On this evening, her discomfort worsened, and she called 911 and EMS responded.
En route you are contacted through BioTel that they would like for you to come and look at the transmitted ECG. They are worried that the patient may need cardioversion (see V1) or to at least go onto an antiarrhythmic drip. The following 12-lead is handed to you as you walk into the radio room. Look at V1. You have to make a decision NOW. Make your decision as to what to do.
This ECG shows a borderline sinus tachycardia with left axis deviation that does NOT meet left anterior fascicular block criteria (-31 degrees). There is mild prolongation of the QRS complex, and there are Q waves in Leads I and aVL that are not “significant” (are not a third or more of the following R wave). The machine tries to call it “atrial fibrillation”, but the rhythm is regular. Look at V5… this is probably sinus rhythm.
So what is that stuff in V1? Looks like some kind of burst of a tachycardia at a rate of around 300. What is this?
Remember that the leads of I, II, III followed by aVR, aVL, AVF followed by V1, V2, V3 and followed by leads V4, V5, and V6 are all being tracked simultaneously. So, when you see this blast of a tachycardia in V1, then just look down at V2 and V3, which are showing different angle looks at the same beats. As you see, there IS no burst of tachycardia in those leads. So, what that is in V1 is just garbage. A trick that is good to know!
An 80 year-old male presents in acute distress with the worsening of chest tightness over the last few hours of the afternoon. He has had this before, he has stable angina, he has had a previous stent placed in the LAD, and he is compliant with his daily Plavix use. The ED is packed, the triage nurse has brought him back in a wheelchair, and he speaks only Burmese. What would you do?
The ECG shows a rapid, narrow-complex rhythm at a rate of 135 that measures at 102 ms. The axis measures -53 degrees, so this is consistent with a left anterior fascicular block (LAD with LVH can cause a similar appearance). Notice the ST segments in aVR, V1, and V2. This is quite worrisome for an Acute Anterior Myocardial Infarction with reciprocal depression. I would sure want to compare the tracing to previous ones, but this is a brand new patient in the ED.
In the meantime, this is a sick man. This is a near maximum output sinus tachycardia in an 80 year-old with prior existing coronary artery disease. The inverted P wave in V2 suggests left atrial enlargement, and you wonder if this man has some decompensation of valvular disease. This is a booth player, with VS q5 minutes, and get CCU team on the phone in a hurry while providing oxygen, IV’s, appropriate labs, old chart review…..following, of course a quick but precise physical looking for ejection murmurs or diastolic rumbles. Valvular insufficiency presenting with this kind of distress can rapidly deteriorate….may need to talk to CVTS!