What's the rhythm?

[itxtme]

The occasional inverted p waves could still be MAT if the foci is low in the atrium and fires in upward direction first, correct? I'm blanking on the term.

No I do not believe so. In a PJC the the pacemaker is from junctional pacemakers, this firing heads upwards to the atria causing a either missing (hidden) p wave [as in the beat I have highlighted] but ultimatley it is below the atria. During MAT the starting point of the firing is still the atria so the firing doesnt need to head up per say to fire the atria.. Hope that makes sense.

As another aside apart from the missing P wave in the junctional beat you can see quite a differing pattern of the QRS (comparing to the other QRS complex's) indicating a significantly differing pace maker sight.

[FL_Medic]

My initial impulse is MAT.

What is the difference between MAT and WAP?

[scott33]

My initial impulse is MAT.

What is the difference between MAT and WAP?

The rate.

MAT = >100, WAP = <100

[FL_Medic]

The rate.

MAT = >100, WAP = <100

gracias, that's the only difference? What's all the hoopla about?

[Mateo_1387]

I disagree with MAT or WAP. Although the rhythm is irregular, the PR interval remains the same.

I think you are dealing with sinus arrhythmia along with an ectopic beat.

Here is why:

PRI remains the same.

R-RI at times is regular, then becomes irregular.

(except one) a p-wave for every QRS.

QRS for every p-wave.

P-waves are round and upright. (not different morphologies as is WAP or MAT)

Edited March 10, 2009 by Mateo_1387

[FireMedic65]

I agree with Mateo

[FL_Medic]

The PR-interval does change, and there are a few different p-wave morphologies including some that are biphasic. I believe this is MAT. Not that it makes a huge difference.

[scott33]

P-waves are round and upright. (not different morphologies as is WAP or MAT)

Look again at the PRI and shape of the p-waves, particularly on lead II and III on the 12-lead trace. Nothing is the same - variable PRI, notched P-waves, pointed P-waves, biphasic P-waves, retrograde P-waves etc.

Perhaps the OP can scan it a little larger for those in doubt.

[FireMedic65]

How come none of the know it all posters on here who know everything else in EMS haven't given their opinion on it yet?

[scott33]

How come none of the know it all posters on here who know everything else in EMS haven't given their opinion on it yet?

Because the puzzle was solved by the second post.