T-Waves in Afib

Specialties Cardiac

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Can I or can't I positively identify T-waves in afib?

Sometimes I think I can see them and want to measure but then it could always be a P-wave, right? Should I not even bother once I recognize the rhythm is afib?

T-waves CAN be identified in afib, and by definition, there are no true p-waves in afib. I often see patients in afib, with depressed ST and/or an inverted t-wave. I can't recognize t-waves in every instance of afib though, probably in most of them I can't.

The little bumps in between QRS complexes do seem like p-waves, but depending on the strength of the atrial fibrillations, there may be no bumps at all. Afib isn't only recognized by the bumps in between QRS complexes, but also by irregular R-R intervals.

Does that answer your question?

Based on what you said, it sounds like I should measure the T-wave if I suspect that's what it is. But it's entirely possible that I won't find T-waves in which case it's okay to say it's unmeasurable. Yes?

Yep, that's what I was getting at. I'm not an EKG expert, but I work on a tele floor and that's just what I've noticed with my patients.

Here is a link with several different variations of afib:

http://floatnurse-mike.blogspot.com/2012/07/ekg-rhythm-strips-atrial-fibrillation.html?m=1

The first one has an inverted t-wave. You'll also see some with a normal t-wave, and some with no t-waves. Hope this helps.

Specializes in ED, School Nurse.

Also, it helps if you think about what atrial fibrillation is physiologically and what each part of the PQRST wave represents. Atrial fibrillation means the atria is in fibrillation, so instead of a nice strong coordinated contraction the atria is quivering with lots of little uncoordinated contractions (which equates to the squiggly base line you see in a fib). The atria contracting is what makes the P wave, so it makes sense that in a fib you won't get a P wave- just the squiggly baseline. The QRS and T wave all have to do with the ventricle contracting and repolarizing so you do see those in a fib, but they're irregular. Hope that helps! :)

Right. I agree with both of you. Ohiobobcat you made me think that if I can measure a consistent QT interval, then it's likely a T wave. I think my problem was stemming from a patient who was in afib/flutter so the whole thing was unclear as waves kept presenting and disappearing. I appreciate both of your help.

Specializes in Public Health, TB.

I agree T waves are often distorted in Afib or flutter, however is is important to try. Often these patients are receiving meds than can prolong the QT interval and and you would want to identity a QTc >.50 mm, before a patient goes into Torsades.

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