60 BPM

I was lying in bed and took my pulse. It was 57. I thought your rate couldn't go below your set rate. In My case it's set for 60. I started to worry because it would go between 57 and 61! Is this normal? My PM was installed 11/27/15. Thanks!

8 Comments

Thanks!

by Pastorm - 2016-02-27 10:02:14

Thanks for the comments! I have felt Great, but I pulled a leg Muscle and after I got Up and went back to bed, I felt My Pulse at 57. That's when The old Anxiety kicked in! I am now 3 months out and have been doing pretty much everything! I am Amazed at how much this group knows! It really is a comfort knowing what You have All experienced, and share! thanks Again! Pastor Mike

Normal

by Good Dog - 2016-02-27 11:02:36

Yes, it is absolutely normal. A slight departure from the low set point could be the result of any number of things including an error of a couple seconds in counting. As long as there isn't any significant difference (above 5%), then I would not worry. If it was, say 50-55, then I'd get it checked-out.
I think we are all too often hyper-vigilant monitoring our pulse after getting a PM. That isn't a bad thing necessarily, but the longer you have the PM and the better you feel, the more you will trust in it.

Sincerely,
David

normal

by Tracey_E - 2016-02-27 12:02:44

(posted earlier this week)
Set at 60 doesn't mean exactly 60 beats per minute, it means approximately 1 beat per second, so 55-56 over the course of a minute is close enough to be considered 60. Some things to keep in mind
- monitors are notoriously inaccurate with us, always count manually when in doubt
- pvc's will throw off the count
- sometimes there are weaker beats between the strong beats that we miss when we count

If you don't feel well, then take your pulse. The rest of the time, try to resist the urge. You'll just make yourself crazy with all the nuances. If you feel bad or it gets lower than the low 50's, call your doctor.

Heart Rate

by Grateful Heart - 2016-02-28 02:02:09


My lower setting is set at 70 bpm. It went as low as 57 according to a holter reading last year. The doctor wasn't worried about it.

Today at the gym my HR monitor read 46 at one point. My HR monitor has been pretty accurate so far.

Probably PAC's in my case....I get them more than PVC's.

Grateful Heart

Donr True, BUT

by BillH - 2016-03-01 02:03:58

While the time is very accurate and you mentioned possible noise & capture problems, there are also PM setting that can cause this.

One is automatic mode switching of ventricle pulsing. In some cases the PM can stretch a wait time to see if the natural pulses have returned. But I think that might be only for a beat or two.

Another setting is hysteresis. After a number of natural atria pulses that slowly drop the PM will allow it to a lower hysteresis limit. That is to allow more natural action of the heart when resting.

It's time to throw...

by donr - 2016-03-01 03:03:59

...all our dead rats on the table (To quote a associate I worked with in a former life.)

My dead rat is on the precision & accuracy of PM timing./

has anyone besides me tried to Google search & find out just exactly how precise & accurate PM's are in the timing end of their business?


Well, I did just for this thread & I could find nada, zilch, bupkis, absolutely NOTHING.

I was reduced to reading old patents in my desperation to write a comment. FINALLY, in a paper presented at some obscure conference in Lower Slobbovia I found SOMETHING!

The subject of the paper was something along the line of instrumentation needed for manufacturers to perform Quality Control on the devices. The conference was in 2012, I believe, so it would be applicable to current generation PM's.

As I read the bottom line on timing intervals, the precision was single digits in 600. The accuracy was =/- 1 millisecond for that 600 ms attribute. That's a wicked .16% accuracy. Since a typical heart beat is ONE second long, the worst the PM will be off due to timing error/variance is in the vicinity of 2 milliseconds - nowhere near enough to make a sensed HR off by even one beat.

Given that a PM's timers for measuring events is repetitively reset to zero for every beat, there is no way that a PM could give you even a SINGLE beat less than the lower level it is set for from TIMING errors/variation.

So - where does that variation below the set point come from?

Most likely from an error in the sensing system we use to check out our PM's. A finger at the wrist or against the carotid artery could easily miss a beat. Especially if the person performing the count was inexperienced. Commercial HR monitors are notorious for being inaccurate or spoofed by a PM. Throw in some whacko arrhythmia & there's no telling what they may count.

Supposing there is a truly absent beat by a paced heart - most likely that will be due to some sensing/capture/pulse output energy error, as opposed to timing error. That timer is better than the good ol' Energizer Bunny!

Donr

Accuracy

by Grateful Heart - 2016-03-03 04:03:25


So the holter reading of 57 bpm when my lower limit is set at 70 bpm means the holter was wrong?

Grateful Heart

in this corner, the Holter...

by donr - 2016-03-03 05:03:34

...GH: i'm not sure of what to say. A 57compared to 70 is about a 20% error. That is totally unacceptable for a PM!

As I said, the accuracy expected is about 1 ms variation out of 600. Were i the EP looking at that variation, i 'd be very concerned that something is very wrong - it does not pass the common sense test at all.

What did he finally decide what the problem was?

Was this the guy you didn't like?

DOnr

You know you're wired when...

The mortgage on your device is more than your house.

Member Quotes

Sometimes a device must be tuned a few times before it is right. My cardiologist said it is like fine tuning a car.