Sinus Brady vs. Junctional?

Specialties Cardiac

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Specializes in Cardiac Telemetry, ED.

Strip shows sinus bradycardia, then the PR shortens until the P is nearly buried in the QRS, and the QRS's are widened and monomorphic, but the Ps march out, and there is no rate change.

I thought in junctional, the P would be inverted or absent, and the QRS would remain narrow.

I guess my question is, what is the significance of the shortened PR and widened QRS? Could this be a junctional brady, or is this some form of post PTCA ventricular irritability?

How slow was the rate? The typical junctional rate runs 40-60, with a junctional bradycardia giving you a rate less than 40. How long did the PR/QRS changes last?

Specializes in Cardiac Telemetry, ED.

The rate was in the 40s and the changes lasted about eight beats.

Specializes in Cardiac Telemetry/PCU, SNF.
Strip shows sinus bradycardia, then the PR shortens until the P is nearly buried in the QRS, and the QRS's are widened and monomorphic, but the Ps march out, and there is no rate change.

I thought in junctional, the P would be inverted or absent, and the QRS would remain narrow.

I guess my question is, what is the significance of the shortened PR and widened QRS? Could this be a junctional brady, or is this some form of post PTCA ventricular irritability?

In junctional the PR will be .12 or less, inverted, buried in the QRS or retrograde (post-QRS), but the QRS should still be narrow as the beats are rising from the junction. The wide monomorphic ventricular beats sounds like a ventricular escape rhythm, the rhythm rising from below the node. Without seeing an actual strip it kind of sounds like transient 3rd degree block... The big question is: is there a relationship between the P-waves and the QRS complexes?

Also, what artery got ballooned? Did they get stents? Was it just once? It does sound like some post-cath irritability, but would make sure to bring it up to the docs.

Tom

Specializes in Cardiac Telemetry, ED.

I don't recall which artery was opened (they used a cutting balloon). The Ps marched out, and every QRS had a P, but the PR interval was short, probably about .08 or less, even partially buried in the QRS.

I pointed it out to the nurse who was assigned the patient, but I don't know if he called about it.

Any way to scan the strip and attach the image to this thread? With P waves buried in the QRS and wide QRS morphology, I would consider third degree AV block as well. A ventricular pace maker would create the wide QRS morphology as you have slow retrograde movement of depolarization and possible extreme right axis or right shoulder deviation.

Any access to a XII lead? AV blocks and bradycardia are a common finding with a compromised right coronary artery. This would involve the inferior wall in most patients. So, looking for changes in leads II, III, AVF, and V4R could be helpful as well.

Specializes in Cardiac Telemetry, ED.

Nope, patient was DCd. Ah well. Thanks anyway!

How about sinus bradycardia with PJCs and BBB. BBB is common with MIs... I know you said the P waves were regular but if some of the ps were buried in the QRSs and others weren't there's no way that the ps would march out?? I guess I would have to see...I wish i could see the strip...There is a possiblility that the patient had sick sinus syndrome, also.

Specializes in Cardiac Telemetry, ED.

Pt. did not have an MI. It was a scheduled procedure, in for overnight obs. post PTCA. No BBB. P waves were regular, marched out, the PR interval was shortened, which is what partially buried the Ps. I'm thinking some sort of ventricular ectopy.

I realize that you said the p waves march out, but with BBB it is the QRS that is wide (>0.12). You're not confusing this- are you or you saying you know for sure it wasn't BBB (based on the fact the QRS wasn't wide)? It is difficult to analyze it without a strip and know exactly what the measurements were. Sorry if I wasn't of much help. EKG strips definately can get a little interesting.

Specializes in Cardiac Telemetry, ED.

Yeah, it is hard to say without the strip, and kind of hard to go on memory. I'll keep that in mind next time I see something funky.

My first impression of the tracing you mention is IVR...idioventricual rhythm.

The first time I saw this it was like my P wave just melted into my QRS and it had gotten wider then my P wave just emerged out of my QRS and had returned to it's normal morphology.

AIVR is accelerated idioventricual rhythm: a rate above 40.

Hope this helps.:redbeathe

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