low heart rate

About eleventy billion things.

The most likely suspects are medication or sick sinus syndrome, but without knowing more it's just speculation.

Generally, the SA node fires at 60 - 100 BPM. If that fails the AV takes over, at I think 40 - 60. If THAT fails the Purkinje fibers kick in, at 20 - 40. I think those are the usual rates.

So the electric company, the SA, has a blackout and the back-up generator, the AV, ran out of fuel. So you have someone on a bicycle, the Purkinje fibers, pedaling furiously to keep a charge in that battery.

A number of things can cause this.

dang, it could be a millions things.

cad, valve problems, pump malfunction, sclerotic vessels, electrical, meds (digoxin, beta, calcium ch blockers), hypothyroid, lung disease...and often, idiopathic.

but i agree that you likely r/o sss and meds.

leslie

Resting HR in the 30's... could also be Lance Armstrong or Michael Phelps, but I guess those guys don't c/o dizziness...

If this wasn't a chronic condition & was an isolated incident, I would suspect a vasovagal episode.

If this was her baseline, ditto on what others have said.

Was the pt. on tele, or did you get an EKG? Was it a sinus rhythm?

Generally, the SA node fires at 60 - 100 BPM. If that fails the AV takes over, at I think 40 - 60. If THAT fails the Purkinje fibers kick in, at 20 - 40. I think those are the usual rates.

So the electric company, the SA, has a blackout and the back-up generator, the AV, ran out of fuel. So you have someone on a bicycle, the Purkinje fibers, pedaling furiously to keep a charge in that battery.

A number of things can cause this.

In theory, yes, this is true. But, just because the rate is low, does not mean it is originating in the AV node or the ventricles. Sinus bradycardia originates in the SA node, and can go as low as the 20s-30s. The AV node and purkinje fibers don't necessarily kick in and take over the pacemaker function when the SA node is firing at a low rate. People can have sinus pauses that last for several seconds with no junctional or idioventricular beats. Real hearts don't always fall neatly into the categories we learn in EKG class. Without an EKG, it's not really possible to say what was happening in this case.

Was the pt. on tele, or did you get an EKG? Was it a sinus rhythm?

Hey Virgo (me too, by the way--actually on the cusp, Sep 22), assuming everything reported is accurate, could a pt have a sinus rhythm that low? I suppose they could if they had too much dig, or beta blockers or something, but you'd think there would be an escape rhythm--a junctional rhythm of some sort or ventricular escape beats.

The OP must give us more info.

Ah, I see you posted the answer to my question. Beat me to the punch as it were.:typing

I've seen sinus brady that low, and no, you won't always see escape beats.

I've seen sinus brady that low, and no, you won't always see escape beats.

I see sinus rates that low almost daily (monitor tech), and almost never do any of the downward pacers kick in.

In a little over a year, I've seen a junctional rhythm once. I've never seen an idioventricular rhythm.

In theory, yes, this is true. But, just because the rate is low, does not mean it is originating in the AV node or the ventricles. Sinus bradycardia originates in the SA node, and can go as low as the 20s-30s. The AV node and purkinje fibers don't necessarily kick in and take over the pacemaker function when the SA node is firing at a low rate. People can have sinus pauses that last for several seconds with no junctional or idioventricular beats. Real hearts don't always fall neatly into the categories we learn in EKG class. Without an EKG, it's not really possible to say what was happening in this case.

Yes, Virgo, I realize that my explanation was simplistic. I posed it as a beginning, not a comprehensive analysis of all bradycardia.

:)