Rapid A. Fib or PACs?

[harley_fan]

This may be a dumb questions but.. I had a patient that was in A. Fib and would have a couple beats that some nurses called PACs. I'm wondering if someone is in A. Fib could they have PACs or would this just be A.Fib with RVR for a few beats. Any clarification at all would be helpful. Thanks!!

[steelcityrn, RN]

Yes, you can have afib with runs of pac's.

[VicChic]

Yes, that's correct. In fact, sometimes frequent PAC's are an indication of an underlying or impending atrial arrhythmia like A-Fib coming on.

[VicChic]

And no this was NOT a dumb question at all. On the contrary, it actually shows good critical thinking skills. Way to go!

[Tweety, BSN, RN]

Yes, you can have afib with runs of pac's.

I'm confused. If the hallmark of a-fib is irregularity how to you do if the PAC is premature?

[VicChic]

I'm not exactly sure about your question Tweety, but I think you're asking about how can you tell what beat is the premature atrial contraction if the PAC makes the rhythm irregular and the A-fib itself also makes it irregular? To answer that question, remember that although both PAC's and A-fib both make a rhythm irregular, between PAC's and A-fib, only the PAC's will have an actual p wave indicating the atrial contraction. True Afib will NEVER have a true, distinctive p wave b/c the atria is FIBRILLATING, not contracting. So in Atrial Fibrillation with frequent/occasional Premature Atrial Contractions, look for distinct p waves to tell which are true PAC's.

I hope this helps to clear things up. If it doesn't, I'm sorry, but someone else might get it for ya' next time.

[telehead]

True Afib will NEVER have a true, distinctive p wave b/c the atria is FIBRILLATING, not contracting. So in Atrial Fibrillation with frequent/occasional Premature Atrial Contractions, look for distinct p waves to tell which are true PAC's.

I won't presume to speak for Tweety, but I think this is where the confusion comes from. My interpretation is as follows: As you state, with true afib, you have no distinctive p waves- the distinct electrical representation of a single focus discharge. But unless the hr is 60 or below and you're running on a junctional or ventricular pacer, the discharges in the atria are present- they just occur as multi-focal discharges. As such, this ectopy can occur anywhere (and everywhere ) in the atria. With no regularity, it can't truly be a pac. In my mind, the only way I could note pac's on strip containing afib is if the heart is extremely irritable and you have brief flops from fib to sinus and back again. In that case, I could see a regular pattern, if even only for 6-10 beats and witness a pac within that stretch.

That's my thinking... where are my holes?

[Tweety, BSN, RN]

I'm having trouble visualizing a heart in fibrillation, suddenly producing a single PAC and staying in fibrillation. It's easier for me to understand if they go back into a sinus rhythm, then throw PACs, then back into fib and back and forth. This I have seen.

I don't know much and I just worked a 12 hour shift, but I can't see fib with PACs in my little tired brain.

[LCRN]

To my understanding if someone is in true atrial fibrillation they cannot have a PAC because as said previous in the post there are no distinct P waves and the atria are "fibrillating". The only thing I can think of--> if the patient broke into a sinus rhythym and was trying to go into afib--> possibly that's what nurse's were visualizing on the monitor.

Frequent PAC's can be an indication that the patient is trying to go into a-fib however if the patient is in a fib you will not have PAC's.

LCRN

[Spidey's mom, ADN, BSN, RN]

See!? This is why is hate hate hate heart rhythm stuff!

I swear, every time I ask a question at work about a rhythm strip, I get a different interpretation. It is so frustrating.

And when you ask how you measure, oh boy .. watch out.

:sofahider steph

[VicChic]

Oh that's the beautiful thing about rhythm interpretation--it's open for interpretation. Then you get to have an interesting discussion about the "interpretations" like the one we're having now...until an experienced cardiologist comes in and says, "Nice try but you're all wrong. It's really ___." (LOL) Just comes with the territory.

Fortunately, when you have funky stuff like Afib/PAC's/Afib w/ PAC's, the treatments don't differ too much. For instance, a pt who is sinus with freq. PAC's which later converts into A-fib will most likely go on an antiarrythmic like Cardizem for rhythm conversion and a beta-blocker like Metoprolol for rate control. As you know, beta blockers slow down HR, sometimes as an unwanted side effect, but in the case of A-fib, you want to slow down the heart to allow those "fibrillations" or "quiverings" into true strong contractions. You may see PAC's w/ Afib as a sign of the midpoint of the heart getting ready to convert back into sinus rhythm (or brady since you now have a slow HR, but at least it's SINUS), just like you when you saw the PAC'S as the indication of A-fib conversion. It's simply just a reversal of the previous processes.

[Spidey's mom, ADN, BSN, RN]

All our docs are family practice but they all have a "leaning" and one is trained in cardiology. He usually comes in a does as you say, clears up the issue.

It seems to me though, that since this is electricity, it should be easy, it should be black and white.

But thanks for the post VicChic.

steph

p.s. Sorry for "shouting". :-)