Ejection fraction


I had a few tests done after complaining of exercise causing high heart rates from minimal exertion. My 48 hour cardiac monitor showed good rhythm during exercise and whilst sleeping, between 70 and 160 over two days and an 80 average, he said he may consider lower the heart rate to 60 and maybe even 50 to increase the range. The echo showed an ejection fraction of 48% which he is slightly concerned about being how you (24) I am, He is looking into finding if it is the heart or the pacemaker causing this, is it's the pacemaker he will adjust settings away from the norm to suit me as best he can, if it's the heart he will prescribe some medicine to strengthen the heart. 

I asked about turning off rate response but the problem is I'm paced 55% of the time in the atria and 100% in the ventricle and so they are worried as you would usually only turn rate response off under 30%.


I was wondering if anyone found any settings that were changed which helped with being there EF back up??? 






by Lavender - 2022-07-05 22:53:50

I see that you've had a lot of replies to your previous post. This one has a lot of views but no replies. Perhaps folks have given all the input they can think of. 

I have a Boston Scientific dual chamber CRT-P. My rate is set 60-130. My ejection fraction improved to 55%. Normal my age is 55-65. 

It may improve on its own and pacemaker rep said sometimes pacemaker helps that. I'm 100% paced.

You are young and active. Hopefully your pacemaker tech can tweak the settings to suit you better.  My cardiologist does her own pacemaker clinic but sometimes I think it might be more helpful to consult with the EP who put the device in. 

My rate response is turned off. My sinus node is fine-it's the AV node that's not working. 



More Investigation Needed

by SeenBetterDays - 2022-07-06 08:15:35


I think you need to establish if you havea sinus node issue.  My understanding is that the rate response setting is only needed with sinus node dysfunction.  Maybe other members can confirm  if my understanding is correct.  If the sinus node which triggers the heart beat is not working properly then I can understand why there would be concern about switching this off.  It might be worth you looking back at other posts relating to rate response settings as sometimes they can be oversensitive, for example, upper body movements elevating the heart rate excessively during activity (this would depend on your pacemaker model).

My other thought is that it may be worth trying out a lower base rate.  This should help to reduce the pacing percentage as your intrinsic heart beat may then effectively kick in before the pacemaker.  This could help to reduce your atrial pacing at rest.  

You might have seen my previous posts about pacemaker induced cardiomyopathy.  My ejection fraction has significantly dropped since my pacemaker implantation and I am also 100% paced in the ventricles so it may be worth you reading around that, although I would also caveat those concerns by saying that there appear to be many people on this site who have a high level of ventricular pacing and are fit and well.  My aim is not to worry you unnecessarily, just to highlight a potential problem for some individuals. 

There are clearly many reasons for a fall in ejection fraction but it definitely requires further monitoring and investigation.

I am sorry there are not easy answers to some questions, it might be a process of trial and error with settings as we are all individuals and unfortunately there is no one size fits all approach (if only!).  Keep talking to your EP and hopefully you will be able to work out some strategies and potential tweaks which could help you.

Good luck and let us know how it goes.


Ongoing investigation

by Grantbibby98 - 2022-07-06 09:57:11

Thank you both for your comments. I've been pushing hard to get this sorted, thank god I have private as the wait times for me are a couple of weeks! I went in today, got my lower rate set to 60 as I was being over paced and kept at 70 for no reason. My rate response has also been turned off now as my heart is able to get its rate up just fine. They have also set my upper limit to 180 in my ventricle, up from 170 which is good for exercise as it stops the pacemaker switching moods, other than that I'm gonna get another echo done to see if the EF changes over the next month. If not then I'm gonna push for any method of CRT before it gets worse, I'm not one to wait till it's irreversible!


thanks again,




by ROBO Pop - 2022-07-07 16:42:03

You guys...I'd kill for an EF of 48%. And Lavender do your homework, any EF 55% or higher is considered normal. In fact some medical proffessionals consider 50% normal. 

Don't believe me? Ask your Cardiologist. Stop worrying about nothing. Guaranteed insurance will not cover a CRT for an EF of 48



by Lavender - 2022-07-07 21:59:06

Yes I know mine is normal now. As I stated, "My ejection fraction improved to 55%. Normal my age is 55-65. " That normal is per my cardiologist. 

I'm sorry Robopop-I did read about your low EF. 

You know you're wired when...

You have a $50,000 chest.

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