pacemaker info

Percentages

by Gemita - 2023-11-06 10:54:09

Hello Bernwenz,

It looks to me as though your check up was all too brief and I am sorry you didn't get much in the way of an explanation of how things were going.

Your pacemaker is pacing you 15% of the time in the top right atrium and 25% of the time in the bottom right ventricle.  This means that your heart is functioning a lot of the time on its own without needing pacing support, which is a good sign.  

Of course those percentages are not always meaningful since they can go up and down.  Even with 100 % pacing in either the upper or lower chambers, these percentages could change.  For example because of a change in medication which could slow conduction, or a change in heart rhythm, or due to settings changes.  

What is important is that we feel well.  If we feel relatively well and have few symptoms, we could say that our pacemakers are pacing us at the right speed and appropriate settings.  If we have symptoms, then we might look at our settings, other health conditions present, lifestyle, medication and so on.

So how are you "feeling" being paced at those percentages.  Do you have any difficult symptoms?  

Just a little clarification about pacing percentage

by Gotrhythm - 2023-11-06 17:51:04

The pacemaker doesn't pace in the atrium and ventricle in preset amounts. The pacemaker is intended to pace only at the exact moment you need for it to.

The pacemaker times every single beat of your heart, all day, everyday. The pacemaker "knows" when the next beat should come. If it comes on time, the pacemaker does nothing. It just keeps on timing.

But if the beat doesn't come when it should, the pacemaker steps in and supplies a beat. Just one. And goes back to timing. It does this as often as it needs to.

So "percentage paced" tells you what percent of the time the pacemaker is pacing, i.e. supplying a beat.

The percentage paced isn't a hard and fast number. A higher or lower percentage isn't either a good or a bad thing. Many times changes to your settings will result in changes in the percentage paced. In the 13 years I've had a pacemaker, I've seen the percents go up, go down, go up, go down--in my case, especially in the ventricle. After a recent settings change the percent paced in the ventricle went from 3% to less than 1%. But I have seen it as high as 30%.

We as pacemaker recipients sometimes focus on percentage paced because it's the one number on the report we can actuallly comprehend. It's interesting to note, but not terribly significant in and of itself.

As Gemita says, what matters, what always matters, is how we feel.

Out of here

by piglet22 - 2023-11-07 06:24:52

The "pacemaker is fine" line often heard in PM clinics.

Reassuring, but sometimes is not the whole truth. The PM might be following it's settings and preset algorithms, but your heart may have other ideas.

Ectopics or premature beats can play havoc with PMs and bring on the very symptoms the PM is supposed to be fixing.

As Gemita and Gotrhythm say, you might not feel fine and that can be hiding things going on that aren't always passed by routine clinic visits.

Interesting to read Gotrhythm's explanation of the timing routines.

I don't know how the PM is programmed, but it has a basic function of maintaining a healthy heartrate when our own pacing mechanism has broken down.

It will have a setting which is the IPG (Implanted Pulse Generator) base or minimum rate, often 60 or 70 beats a minute.

This is the guaranteed heart rate, in theory, and should not go below that.

In computing and electronics, there are things called watchdogs which operate exactly like a PM and expect to see a pulse, electronic, to say all is well. These watchdog pulses must occur in a set time window, say one second, or the device will send an alarm. A PM does the same, but the alarm is a pulse to maintain the IPG base rate.

The one second timer is reset every time it gets a legitimate pulse or one that has been generated and this goes on for the lifetime of the PM.

So, if your natural PM supplies pulses that fall in the set window, the PM does nothing and waits for the next one detected.

For those of us with 100% PM dependency, we can be running on PM timed pulses full time.

When you get figures like 15% ventricular pacing and feel your pulse, one in six pulses will be PM generated.

Depending on your type of pacing problem, don't be surprised if this changes over time and can progress to full blown 100% dependency.

Don't worry though, you won't notice as your fantastic little box of tricks takes over.

The hard bit sometimes is getting your head around the fact that a lithium battery and some very clever silicon chips are doing the job for you.

On the news today, a Parkinsons patient able to walk unaided thanks to another research group and a clever electronic implant.