Base Rate and Rest Rate Settings

As a larger athletic person, I've always had a lower than average resting heart rate. When I got my pacemaker in August, they programmed it for a base rate of 60. I thought, that's fine, let's just let it go while my heart gets adjusted to having a PM. Later I determined the PM (St Jude/Abbott Assurity) also has a Resting Rate feature that is disabled. After a 30-day interrogation I see that my atrium is being significantly paced, about 25% of the time, but virtually only at my base rate. My SA node and atrium don't really have a problem and shouldn't need so much pacing. They just naturally want to run slower.

I spoke to my EP about this this week and he agrees that this is more pacing than needed and that I could benefit from having the rest mode enabled. There is also a benefit in saving battery life if there is less pacing.

I'm looking for comments from others who've been in a similar situation. Do you have your rest rate feature enabled, and at what rate? Did you also have your base rate lowered or leave it as is? I hope to learn from your experience before making some tweaks. Thanks.


Sleep or Rest Mode.

by Selwyn - 2023-10-04 13:44:12

I have taken the liberty of copying my comment from 30th September:

Some pacemakers have a REST MODE setting ( this can be turned on and off). The rest mode will function, if for instance you are prone for 20 minutes with little movement. As soon as you get up the rest mode is turned off and then the lower limit BASE RATE comes on ( 60 bpm for yourself).

The Rest Mode is used to save the battery ie. to increase your pacemaker longevity. 

The St Jude pacemaker's rest mode is activity based

Medronic and Biotronik are time based ( learnt from your activity pattern)

Boston Scientific is hyperesis based ( ie. it gives you the chance to slightly over-ride the programming so that if possible your own intrinsic  heart rate can take over- as Gemita says above. Hysterein (Greek)=to be late - ie. the programme introduces a delay to give your own rate a chance to function).

I don't think you need worry. Yes, you can be paced below your base rate when you have active your sleep settings.

( Interestingly enough, my hearing aids do the same and switch themselves off if I have an afternoon snooze!).

It is up the your EP to set the rest rate. Usually, with the St Jude, the accelerometer will turn this off as soon as it detects activity ( eg. going to the WC at night). The whole point of the rest mode is to pace you below your lower threshold limit.


by Penguin - 2023-10-04 15:22:18

First option - If you have an Abbott / St Jude device and have Rest Mode enabled your rate will fall each time that you rest for 20 mins or more. This is explained above.  The Assurity device can be programmed with a rest rate which is available at 30 bpm and in incremental steps upwards. You should speak to your doctors about the best rate to select if you choose this option and you should be aware that your heart rate will fall to the chosen rate when ever you sit down and rest as well as when you sleep or are unwell and laid up for any length of time.

Second option - A hysteresis is also available on your device although I don't understand the optional settings. A hysteresis was expressed in %s on my previous PM.  A hysteresis will mean that your own heart will beat and if it doesn't beat the pacemaker will wait for a programmable amount of time before it paces you.  A hysteresis commonly is set around 10% of your base rate.  E.g. if your LRL was 60 bpm a 10% hysteresis would allow your rate to go down to roughly 54 bpm before the PM paces you. 

If I wanted to reduce a.pacing in your shoes I would ask for your EPs advice about these two options. 

3rd Option - You could consider tweaking the base rate downwards instead for a more constant, steady rate.

If you have SVT I would be careful about lots of rate changes for the reasons discussed on your previous thread. Therefore I would probably go for the 3rd option, but you have the choice. 


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