Need rhythm interpretation help

BBFRN, BSN, PhD · Sep 2, 2004

Might these be P waves, and not T waves? If so, are they "marching out," or inconsistent with the QRS's altogether? Is the pt. on any cardiac meds?

hoolahan, ASN, RN · Sep 2, 2004

anyway you can scan it and post as a pic? I can't really say w/o seeing it. I first thought of U waves, which occue with hypokalemia, but actually, it seems like it could be a-fib returning, or who knows?? Good question about the meds, there might be a clue in there.

SoldierMedic · Sep 3, 2004

Yeah, scan it for us. I was a telemetry tech for 2 years, I might be able to help you with the interpretation.

I would like to say the patient's progressing to Wenkebach or type II, but if you say the waves are similar to T-waves, that's too big of a wave coming from the Atrium.

Are you sure they're not artifacts?

Let see the strip.

Dinith88 · Sep 4, 2004

The waves are very similar to a T wave and are superimposed onto P waves, QRS's etc. as well as occuring well after real T waves.? Thanks

If these strange 'waves' are seen 'superimposed' on p-waves AND qrs AND t-waves, the most likely answer would be artifact.

If these 'look like t-waves' then i'm guessing they're much bigger than the pt's p-waves. If there's a suspicion that these are p-waves marching out (and not-conducting) the assumption would be 3rd degree avb...BUT that's unlikely if you're seeing 'real' p-waves(with adequate conduction) and the pt's rate is better than 40.

They're definitely NOT t-waves because t-waves CANNOT occur inependant of qrs complex...ie they arent seen on their own. U-waves would be unlikely because u-waves arent that big, and u-waves wouldn't be seen superimposed on qrs or p-waves.

Some drugs would account for your 1st degree avb and slower rate, but a drug is not going to be responsible for the weird waves you've desribed.

I once saw a strip that looked like the t-waves were all over the place and occuring with no rhyme or reason(it was VERY convincing, t-waves and artifact waves were nearly identical)...it turned out to be artifact. Thats what my guess is from your description. Without seeing the strips, i wouldnt be able to say with any confidence....

If you're unable to post a scanned strip, perhaps you could have one of your cardiologists look at it and give you his/her interpretation. If you do, please let us know what he says as we're all curious now!

BBFRN, BSN, PhD · Sep 4, 2004

If these strange 'waves' are seen 'superimposed' on p-waves AND qrs AND t-waves, the most likely answer would be artifact.
If these 'look like t-waves' then i'm guessing they're much bigger than the pt's p-waves. If there's a suspicion that these are p-waves marching out (and not-conducting) the assumption would be 3rd degree avb...BUT that's unlikely if you're seeing 'real' p-waves(with adequate conduction) and the pt's rate is better than 40.
They're definitely NOT t-waves because t-waves CANNOT occur inependant of qrs complex...ie they arent seen on their own. U-waves would be unlikely because u-waves arent that big, and u-waves wouldn't be seen superimposed on qrs or p-waves.
Some drugs would account for your 1st degree avb and slower rate, but a drug is not going to be responsible for the weird waves you've desribed.
I once saw a strip that looked like the t-waves were all over the place and occuring with no rhyme or reason(it was VERY convincing, t-waves and artifact waves were nearly identical)...it turned out to be artifact. Thats what my guess is from your description. Without seeing the strips, i wouldnt be able to say with any confidence....
If you're unable to post a scanned strip, perhaps you could have one of your cardiologists look at it and give you his/her interpretation. If you do, please let us know what he says as we're all curious now!

With all due respect, I believe if the P waves are marching out, it's a Wenckebach (2nd degree Mobitz 1 AVB). If the PRIs don't correspond to the QRSs in any way, that would be a 3rd degree block. And although it's rare, Digoxin toxicity can cause accelerated automaticity in the AVN (thus more PRIs than QRSs). It could also be that the pt converted to an A Flutter 2:1 rhythm- I've seen this happen with A Fib pts after they've been medicated (Cardizem). Dig toxicity can also cause a junctional rhythm, and if a person isn't very experienced with a junctional rhythm, they might not know how they can vary. I agree, we'd have to see the strip to really interpret it.

Dinith88 · Sep 4, 2004

With all due respect, I believe if the P waves are marching out, it's a Wenckebach (2nd degree Mobitz 1 AVB). If the PRIs don't correspond to the QRSs in any way, that would be a 3rd degree block. And although it's rare, Digoxin toxicity can cause accelerated automaticity in the AVN (thus more PRIs than QRSs). It could also be that the pt converted to an A Flutter 2:1 rhythm- I've seen this happen with A Fib pts after they've been medicated (Cardizem). Dig toxicity can also cause a junctional rhythm, and if a person isn't very experienced with a junctional rhythm, they might not know how they can vary. I agree, we'd have to see the strip to really interpret it.

In 3rd degree AVB, the p-p intervals DO march out. the term 'marching out' simply means the P-P intervals are consistant/the same. Thus, they would 'march out' in both 2nd and 3rd degree avb. You're right about no relationship/conduction between p's and qrs's in 3rd degree, but thats different from 'marching out'.

I think you may be confusing the term 'marching out' with some other meaning. It doesnt have anything to do with PR interval...it's referring to P-P interval.

I think from re-reading your point about 'marching out' being a clue to it's being wenchebach, you're under the assumption that 'marching out' would mean a lengthening of the PR with successive beats (as seen in wenchebach)???

And in dig-tox and/or junctional rythm, neither would produce these strange

'moving' waves described by the origional poster. I still think it's artifact.

Dinith88 · Sep 4, 2004

. And although it's rare, Digoxin toxicity can cause accelerated automaticity in the AVN (thus more PRIs than QRSs)..

This statement is incorrect. It's impossible to have 'more PRI's than QRS's'. PRI's measure the distance between the p-wave and QRS complex. So, a pri cannot exist unless it has corresponding qrs. Do you follow???

Perhaps you meant 'more p-waves' than qrs's. Thats entirely possible with dig-tox....and would be some kind of block.

Also, irritable AVN's ('accelerated automaticity') would most liekly produce PJC's and/or junctional rhythms than it would a block...also common in dig-tox

.

Edited to include: Forgot to address your statement about 2:1 flutter. In 2:1 flutter, you dont get wandering waves that overlay the qrs. It's very unlikely for this reason (one), and because the rate is brady (as stated by the poster)(two). Have you ever seen a 2:1 flutter (or any flutter for that matter) under 60bpm??

BBFRN, BSN, PhD · Sep 4, 2004

You are correct- I was typing PRIs instead of P waves. Didn't see the part about the brady...thanks for catching that. :)

SoldierMedic · Sep 5, 2004

Hyperkalemia can also cause weird T wave abnormalities.

Off the topic, I used to have a binder full of weird and abnormal strips I collected as a monitor tech. Too bad I can't scan them for you guys because I ended up giving it away to some RN's at Kaiser Permanente when I became a unit clerk.

SoldierMedic · Sep 5, 2004

Here's a pic of me as a Telemetry Tech :chuckle

critcarenurse16 · Sep 19, 2004

Sorry for not getting back to you all on this one--I'm moving to a new house and have been busy. :chair: :eek:

All of your replys are great, but these T-waves are very random, it does not appear to be artifact but I have no other explaination for its irregularity. P waves march out, followed by QRS's that march out and normal T waves follow QRS's,except for this extra T that appears randomly but frequently through out all points of the EKG-- unfortunately I have no strip to post right now but will try to access med. rec. on my next shift. Thank you all for your help...you're a great bunch! Hope we can figure this out, as we all know anything is possible but not without explaining.