# Discussion for 58 year old male CC: Epigastric pain

This is the discussion for our "Snapshot" case, 58 year old male CC: Epigastric pain. You may wish to review the case before continuing.

Thanks to all of you, we had a lot of great comments!

Many of you had wished we had a rhythm strip to analyze… keep in mind, this 12 lead is a continuous ten second strip, long enough to analyze the rhythm.  Learning how to interpret rhythm off of a 12 lead is a good skill to have!

So, let's review the 12 lead:

So what do we know? We have a bradycardic rhythm with a rate of about 36.  There are visible P waves. The comments were mostly split between 2nd degree AV block type 1 (Wenckebach) , 2nd degree AV block type 2 (Mobitz II),  and 3rd degree block (CHB).  So, which is it? One very important thing to remember about 2nd degree blocks type 1 is that they will be irregular due to the dropped QRS.  In this strip, some considered that there may have been a lengthening QRS and dropped beat, leading to a conclusion of Wenckebach.  However, if you map out the QRS complexes, they are regular.  That pretty much eliminates 2nd degree type 1. There is no constant PRI, which would eliminate 2nd degree type 2 from the differentials, and that leaves 1st or 3rd degree blocks.  At that point, it becomes apparent that it is a 3rd degree block. Rhythms like this can be tricky, unless you look for all of the P waves. In this case, they are easiest to see in V3 and V4.  You should get used to marching them out.  You will find that many are "hidden" in T waves and just after the QRS complex, and may be missed unless mapped out, as I've done below:

The other interesting thing about this rhythm is that the QRS complexes are not wide, as we might expect, but narrow. What does this mean? It means that the escape beats are not coming from the ventricles, but from the AV node or high in the HIS system.  As we know, these beats will perfuse much better than ventricular beats, and no doubt helped this patient remain more stable.

Next, we have to ask a question:  Is the complete heart block is the primary problem, or secondary to something else? Most of you recognized the inferior STEMI, with ST elevations in the inferior leads, and reciprocal depression in leads I and aVL.  Also, notice the ST depression in leads V1-V4.  This is not reciprocal depression, but rather posterior involvement as well! So we have an infero-posterior STEMI, with probable RVI.  You could do a 15 lead, but if you don't, he is already going to the cath lab:

A few things to keep in mind:

• Patients suffering an IWMI often present with epigastric discomfort or burning.
• As the RCA usually supplies the SA and AV nodes, AV blocks and bradycardias are common.
• IWMI often extend to the RV and posterior portions of the heart.

The last thing to discuss is how we would treat this patient.  What about atropine? As was mentioned, atropine is not usually indicated in high degree heart blocks.  However, if the escape is coming from the AV node, atropine could possibly be effective, but not likely. I'm not sure the unapposed sympathetic response is what we are after in this case anyway.

How about pacing? Same issues, plus the discomfort of the electrical therapy.  Our patient is mentating well, and while his pressure is not very high (92 systolic), it is not terrible either. Fluids would be a good option here, and I think i would hold off on pacing unless he was shocky and the fluids didn't help.

It is important to remember that memorizing the ACLS algorithm is quite a bit different from applying it to our patients.  We have to decide what the primary problem is and what will fix it. In this case, the primary problem is an occluded artery, which needs to be opened immediately.  The arrhythmia is secondary to this problem, not the other way around. Some of are teetering on the edge, and the wrong treatment could push them over.  We must always balance the benefit we expect from our treatment against the risk of what could go wrong if we do it.  Is it worth it? Is it in the best interest of our patient? For this reason, we may decide not to give meds or pace, even though it could be justified under the "algorithm".

Unfortunately, we don't have any follow up or additional information to wrap this case up. But I can tell you this: Patients are complicated. Much more complicated than algorithms. We face grey areas and decisions that are not always easy.  That is what makes medicine so interesting… and challenging.

We hope you enjoyed this interesting case. Thanks for reading, and keep up the good work!

• BH says:

We as an industry have created far, far too many medics who simply cannot stomach the idea of "doing nothing," even when "nothing" (if you consider serial 12 leads, ASA, and a fluid bolus "nothing") is the best course of action.

• John says:

I had a pt. like this (minus the MI) when I was a paramedic intern. His was a complete heart block at a rate of about 35 (ish) and when we arrived on scene he very symtompatic (going so far as to puke all over the floor of the grocery store). After he puked however he said he felt perfectly fine. HIs mental status was good, his SpO2 was great and his pressure i think was hovering in the 130's. So my treatment was simply to tell my Intermediate to drive faster. I think these are both good examples of the old saying "treat you patient, not your monitor".

David B.  While I agree with most of what you are saying in reguards to the diagnosis and treatment of this patient, I don't agree with your therory that all 2nd degree AVB's are irregular and the fact that this rhythm had a regular ventricular rhythm it can't be a 2nd degree type II AVB.  If the 2nd degree type II HB is a 2:1 or 3:1 ratio, the ventricular pattern can be very regular.  The fact that it's regular only rules out that it is not a 2nd degree type I.  I did like that you pointed out that the QRS is narrow so the ventricular impulse is originating in the lower junction and using the normal ventricular pathways of the fascicles.  I've heard of this type of 3rd degree block as being a 3rd degree HB Type I, and with a wide QRS being a 3rd degree Type II.

I do agree with the treatment of this patient in this scenerio, since it's been going on for 3 days and he is hemodynamically stable with good cerbral perfusion.  His ultimate treatment is the cath lab and possibly a CABG.  ASA, Zofran (nausea), 2 IV's with fluid boluses to improve B/P, ECG (3) & (12), cath lab alert, and have the pacer pads on and ready.  If you don't need them good.
I really wish that people would get away from the saying to "Treat your patient, not the monitor".  If you have a stable patient in VT.  Are you going to…….Do an IV, monitor with a rapid deisel bolus?  Or are you going to "Treat the patient AND the monitor"?  How about a person who has mild SOB with clear lung sounds and is in a rapid A-Fib?  Do you give Cardizem?  or just transport?  We are there to treat and make our pt's more comfortable, and to anticipate the possibility of decompensation in the near future.  Just because they are stable now, doesn't mean the pt will remain stable.

• David Baumrind says:

Nick A.: Thank you for your comments! I am not sure if i am misunderstanding you… if it's a Mobitz II,  there will be pauses where the P does not conduct… True, it will be regularly irregular (i.e. clumped beating), but it will not be a regular rhythm  due to the non-conducted P waves.

Perhaps i am misunderstanding your comment?

David B.:  Please do not take offense my comments while I can see (read) that you are very knowledgable in your field.  I do believe you are misunderstanding me, so I'll try to better explain myself.  I will admit that it is extremely difficult for most people to understand or differentiate heart blocks, so I'm going to try to simplify it for all to understand better.
While the heart blocks are worsening as the HB nomenclature gets higher, they are all based on the underlining rhythm, which is usually sinus in nature, but you can have an underlining ST, SB or SA.  I have also seen CHB's with A-fib and flutter.  I'll used SR @ 68 bpm as an example.
SR with a 1st degree AVB:  Underlining rhythm is SR @ 68 bpm with a prolonged PRI which is consistent.  Rhythm is regular.  It's just taking longer then 200 ms for the conduction to get through every time.
SR with a 2 degree, type I AVB:  Underlining SR @ 68 bpm with an occasional dropped beat and a PRI that becomes progressively longer until one impulse is blocked.  This causes the rhythm to be irregular…….always.  The impulse takes progressively longer to get through, until one does not get trough because it was blocked.
SR with a 2nd degree, type II AVB:  Underlining SR @ 68 bpm with a frequent to occasional dropped beats. The PRI that does get through to the venticles is consistent.  This rhythm can be regular, regularly irregular, or even irregularly irrgegular, but the P-P is regular.  If there is a 2:1, the P to P is regular and the R-R is regular but there are 2 PW's for every QRS (the atrial rate is 2 times the ventricular rate).  Do not confuse a true 2nd degree AVB, type II with bigeminal nonconducted PAC's, which in theory is a 2nd degree AVB….lol; or a 1st degree AVB type I with a 2:1 conduction (this should have a very slight variability in the PRI).  A true 2nd degree AVB can be extremely regular with a 2:1, 3:1….etc conduction.
3rd Degree AVB:  Underlining SR @ 68 bpm with a consistent regular P-P interval and a regular consistent R-R.  Atria doing it's own thing and ventricles doing it's own thing….no talkie talkie.
Whenever someone goes into a 3nd degree AVB, there is usually a mixture of a type I and type II.  Unfortunately, pt's hearts don't read our text books so they don't like to follow instruction…..lol

Hope this helps all.

• David Baumrind says:

Nick A… No offense ever taken, discussion is what this is all about! I was misunderstanding what you had said, now i see where you are coming from… in the case of "fixed ratio"  with a certain number of P waves to 1 QRS, (2:1, 3:1, 4:1, etc) it will be regular, as you stated.   It was off my radar, because it did not pertain to this case. Thank you for pointing that out, I will ammend my discussion to reflect this point!

The only thing i am not sure about is your comment that bigeminal non-conducted PACs are in theory a 2nd degree AV block… The PACs are non-conducted because the rest of the conduction system is still in a refractory state and not able to conduct.  A so called "physiologic" block, rather than a true "AV" block which may imply some pathology (unless due to drugs, increased vagal tone, etc).