Scenario: would you call this 12-lead?

[281mustang]

49 y/o female with onset of unexplained dyspnea(no hx of copd, asthma, etc.), hx of uncontrolled diabetes(d-stick was 470 which she described as 'low' for her), hypertension, heart murmur, and regurgitation of unknown valve.

Vitals:

HR of 105
156/88
96% sat

Pt is warm and dry and denies any associated chest pain. Pt states her dyspnea is now nearly gone and doesn't want to go to the hospital.

12-lead reveals the following:

What do you do?

 

[Underoath87]

That looks like a septal MI. The lack of pain could be explained by her gender and diabetes.
So yeah, I'd call a STEMI alert.

 

[Brandon O]

Meh.

 

[chaz90]

Not an overly impressive 12 lead. The QRS width isn't overly wide, but V1-V2 are very reminiscent of LBBB patterns...Something to look at and watch, particularly with the QS pattern in V1-V2, but I would not call it at this point.

 

[Ewok Jerky]

Female with dyspnea in the setting of diabetes and HTN? I would bet she is a smoker too. I see ST elevation in V1, V2 and V3 (on my phone, which is bad***). I would call it. She might not get an emergent cath but she is getting a cath soon, on this admission if the CP doesn't resolve. If it turns out negative I wouldn't feel too bad about it.

Any relief with nitro?

 

[Brandon O]

In the general sense you're right, of course, but acutely, this looks like perfectly proportionate discordance in all leads.

 

[Ewok Jerky]

Just reread the OP. If she is breathing normal and without complaint I would AMA if she has a cardiologist and med control was OK with it after transmitting the 12 lead. Like I said she is getting a cath, just maybe not tonight.

**yes I went from calling a STEMI to AMAing.**

 

[281mustang]

Female with dyspnea in the setting of diabetes and HTN? I would bet she is a smoker too. I see ST elevation in V1, V2 and V3 (on my phone, which is bad***). I would call it. She might not get an emergent cath but she is getting a cath soon, on this admission if the CP doesn't resolve. If it turns out negative I wouldn't feel too bad about it.

Any relief with nitro?

No CP, which I honestly didn't place too much emphasis on being that she was a female and probably had severe nervous system abnormalities from years of uncontrolled diabetes. I only ran the 12 lead due to the dyspnea.

I didn't WANT to call it in and was fairly certain that based on the presentation of the elevation it was a mimic. I had my EMT run a few additional EKGs and kept looking for reasons not to call it but as a new medic I simply didn't feel confident enough to leave the situation alone.

I honestly wasn't aware that you could go by the proportionate discordance rule outside of the context of a LBBB or paced rhythm. Does anyone have any (preferably online) material that they would recommend for helping identify STEMI mimics? The exchange at the hospital was definitely an embarrassing experience that I would prefer to not repeat again...

 

[Brandon O]

Serial ECGs are always a sound way to resolve dilemmas.

The principle of discordance works pretty good for LVH, RBBB, and some other things. I have a somewhat exhaustive video lecture on this (http://emsbasics.com/2012/10/26/managing-stemi-mimics-in-the-prehospital-environment-video-lecture/), and otherwise I think EMS12lead.com is the best clearinghouse for this stuff out there.

 

[captaindepth]

Does the ST depression in the high lateral leads concern anyone? It does not look to be a strain pattern. With ST elevation in two contiguous leads and reciprocal ST depression with acute onset of SOB I think activation of the cath lab is appropriate. Definitely going to do everything in my power to get her to go.

281mustang, What was the reception at the ED like? why was it embarrassing if you dont mind me asking?

 

[Brandon O]

What about the high laterals looks wrong to you?

 

[captaindepth]

There looks to be symmetrical ST depression in lead I and AvL with at least 1mm of depression in lead I and slightly less in AvL. With the elevation in V1 and V2 and the reciprocal depression doesn't that pretty much confirm that there is an acute myocardial injury/infarction happening?

 

[Brandon O]

But both those elevations and depressions are deflected opposite the QRS and proportionate in size, which is the expected strain pattern for baseline LVH without acute injury.

(Also, lead I and aVL aren't really reciprocal to the anterior precordials, but rather to the inferior leads.)

 

[captaindepth]

Hmmmm, I am kind of struggling with this one and a few questions.

If the elevations and depressions are normal for LVH shouldn't the voltage criteria for LVH be met? From my understanding strain pattern is not symmetrical depression but more of a downward slope with a rapid return to baseline (seen typically in lead I and AvL as well as V5 and V6). The only LVH criteria I see met here is the tall R wave AvL. Also the QRS is of normal duration so I would not expect the the ST segment to be pushed the opposite direction of the main of the QRS. To me the EKG changes seem isolated and tied to to a vessel group which leads me to my next question, I thought reciprocal ST depression could be anywhere on the 12 lead not just the anatomical "opposite" of the elevation.

 

[Brandon O]

Great questions. Here's the way I'd recommend looking at it:

The principles of the Sgarbossa criteria (not the specific cutoffs and scoring, but the concept of appropriately discordant ST/T changes) apply to bundle branch blocks, LVH, usually to paced and other ventricular rhythms (e.g. PVCs), and sometimes to pre-excitation like WPW. When it comes to something like LVH, this classic strain pattern is pattern recognition across all 12 leads, and you should immediately switch your brain to thinking discordantly instead of comparing against the isoelectric line. Whether the ECG technically meets electrical criteria for LVH is really neither here nor there, unless you're a cardiologist or PCP trying to diagnose LVH (and then you'd probably want an echo).

Does that make sense? It's a little like wondering if something is an "incomplete" or proper bundle branch block or an IVCD. In other contexts it's worth asking, but when it comes to looking for ischemia the same rules probably apply. If it looks like a duck, the principles work.

Here's another duck by way of example (courtesy LITFL):

As for reciprocal changes, using them anatomically is the only way to go. Primary changes that "go together" matched with the right reciprocal changes that is one of the best clues you're dealing with true myocardial injury. The EMS12lead.com gang have a decent write-up on it.

 

[medicaltransient]

Good conversation guys. I agree with LVH. The elevations and reciprocal changes are concerning. I think I would transmit and maybe call report direct to the md. Punt to the md and no STEMI alert.

 

[captaindepth]

Brandon O - It all made perfect sense and the Sgarbossa Criteria is something I definitely need to become more comfortable with. After reading a few different sources on the subjects we discussed I think Im going to stick to my original thought process on this particular 12 lead. Either way, I love discussing 12 leads and practicing interpretation so the more dialogue better. Thanks for such a solid and detailed response!

 

[Brandon O]

For what it's worth, LVH is probably the #1 most common non-ischemic cause of ST elevation (close tie with LBBB).

 

[Handsome Robb]

I was under the impression that reciprocal changes are anatomically opposite therefore high lateral leads are not reciprocal of septal leads.

Also, where are you comparing the elevation to? What are you using to determine your isoelectric line? A common mistake is comparing the ST segment to the PR segment, which can deviate from the isoelectric line for a few different reasons. I have always been taught to compare the ST segment to the TP segment in order to have a better picture of the true isoelectric line. When you do this in this specific 12-lead I don't personally see enough STE to be worrisome.

 

[captaindepth]

I too was taught to use the TP segment as the guide to where the isoelectric line is. In the original 12 lead of this thread I think its pretty easy to see at least 1mm ST elevation in V1 from the TP segment to the J point of the previous QRS. I also see 1mm ST elevation in V2 using the same TP baseline to the previous J point to measure. As far as I remember reciprocal changes, I remember being taught that they could occur in any anatomical area of the 12 lead that is not in the same lead group as the ST elevation, maybe this was a dumbed down answer we were given, Im not sure why but it stuck with me. I believe with the pts acute onset of SOB and this 12 lead its concerning enough to do everything in my power to get her to the hospital. I don't think I'd necessarily call an alert but I'd let them know my suspicion in my radio report.