Ablation and Maximum Heart Rates

I have eluded to this before, but here is a more detailed example of my concern.

After my second ablation in January, a higher resting heart rate is expected and did happened (60 as I sit here typing). It will drop a bit during the year. My issue is with my maximum heart rate which I can't get much over 120. I have been swimming for cardio work for the last 5 months, 2 x week. Because of a hip replacement, and some ongoing issues with the hip, I have eliminated long walks or anything stressing my leg/hip.

I swim a mile each time, with interval training (I am wired for that). While I continue to get faster and stronger, if I swim more than 100 yards without stopping, I am close to oxygen debt (breathing pretty hard). I may swim 100 yds.15 times with a minute rest between each, and that works pretty well. My point is that my maximum heart rate at my age should be around 145 (I am 75), but I am stuck at 120. In my mind, if my heart rate would go higher, I would be less prone to oxygen debt. If I have been tested of oxygen saturation, I don't recall any issues. I am fit and strong (weights twice a week and golf twice a week plus the swimming). I weigh 170 and have no health issues other than afib (turned off at the moment with the ablation). I take no meds, but have Flecainide as a "pill in a pocket" if needed.

Any thoughts as to why I can't get my HR up above 120. I don't recall this being an issue after my first ablation 14 years ago.



Edited 1 time(s). Last edit at 10/25/2020 10:47AM by Ken.

Case report with discussion: [www.heartrhythmcasereports.com]

I've suggested the MAF method for my non ablated afibber son-in-law as a part of afib remission. In a nutshell, the approach recommends exercising at 180-age and working on increasing work that can be done at this level. Have a non-afibber friend who has trained this way for 20 years and has run ~30 Boston Marathons under 3 hours (website).

By any chance are you taking a beta blocker, diltiazem or verapamil?

No beta blockers or anything else, except the Flec as needed - 5 times since March and none in the last two months.

The only thing I can say is that, I agree, 145 bpm seems about right for workout you describe. And, 120 bpm seems low unless you simply aren't working as hard as you think you are. I would think, if you were not working as hard as you have in the past when you averaged about 145 bpm, you would absolutely know it.

So, I don't know. But, if you find out the answer, I'd be interested to know.

So if you get on a treadmill and steadily notch up the speed and incline until you're running at your maximum speed on a steep incline, your HR won't exceed 120 even with no drugs on-board?

I have had noticable changes in heart reactivity following ablation. But was always able to get my HR up to where I needed it.This situation changes over time as well.

It's rather odd you are experiencing this.

From the EP that did my ablation in Dallas, Dr. Kevin Wheelan - "Unfortunately the reduced hear rate might be the result of a gradual decline in function of your sinus node. This does occur with aging and is more common in patients who have had afib". I have another EP in Raleigh where I live, but haven't heard back from him.

Since I am about to be free of hip replacement issues, I will be able to get on a treadmill and push to the limit to actually see what my max heart rate really is. Probably over 120, but not up to 145. What's currently different, is my rather quick dive near O2 debt with a heart rate of just 120. In the past, my recollection is that at a HR of 120, I could maintain that level of work/effort without going into O2 debt. The only thing I can do at the moment to push to my limit is swimming.

A problem unique to me is that when I swim, I am compelled to focus on stroke efficiency, power and technique rather than just splashing along at a comfortable speed - The by product of my competitive swimming and coaching history. Before the hip, I ran dozens and dozens of 5K races and a few longer ones. When training, I could always find a pace that was comfortable and could maintain for long periods. Now, with swimming, it just isn't working that way.

This issue could be more wide spread with those that have had ablations, but if not working out and pushing their limits, people would likely never know.

I looked at some training data I have and before the ablation, my HR would easily go up to 180s and 190s. Since the ablation, I basically flat line at 133, up hills, into the wind, doesn't matter. (no beta or calcium blockers) The only time it goes up is when I stop riding and I may see 144 for 5-8 minutes. If this doesn't change competitive cycling (at any level) is out the window for me. I am really regretting ablation so far. Now in week 10 of blanking.

As I said before, I would guess that most folks getting ablations would not notice a reduction in max HR, assuming that it is a possible phenomenon after an ablation. I will get a stress test when my hip replacement is strong enough to push to my limit on a treadmill to see if there is anything strange with my heart function. Suggested by my EP.

Before my last ablation in Jan., when I did go into afib, my max HR peaked at 110 with no meds. Before my first ablation 14 years ago, my max HR went to 180 while in afib, before beginning meds. It seems that in my case, there is a correlation between ablations and max HRates.

I can't imagine by what mechanism an AF ablation could reduce max heart rate. The procedure doesn't touch any tissue that controls or modifies heart rate.

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NotLyingAboutMyAfib
I looked at some training data I have and before the ablation, my HR would easily go up to 180s and 190s. Since the ablation, I basically flat line at 133, up hills, into the wind, doesn't matter. (no beta or calcium blockers) The only time it goes up is when I stop riding and I may see 144 for 5-8 minutes. If this doesn't change competitive cycling (at any level) is out the window for me. I am really regretting ablation so far. Now in week 10 of blanking.

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Ken
As I said before, I would guess that most folks getting ablations would not notice a reduction in max HR, assuming that it is a possible phenomenon after an ablation. I will get a stress test when my hip replacement is strong enough to push to my limit on a treadmill to see if there is anything strange with my heart function. Suggested by my EP.

Before my last ablation in Jan., when I did go into afib, my max HR peaked at 110 with no meds. Before my first ablation 14 years ago, my max HR went to 180 while in afib, before beginning meds. It seems that in my case, there is a correlation between ablations and max HRates.

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Carey
I can't imagine by what mechanism an AF ablation could reduce max heart rate. The procedure doesn't touch any tissue that controls or modifies heart rate.

It seems we're considering max HR in various conditions...
Here's what I noticed for me :

- Five years ago, my first afib episodes pushed my HR above 160 BPM. I was 57. That was roughly my max HR while exercising too. Of course, as soon as I took HR drugs, it all went down...

- After my first ablation (PVI), 4 years ago, I didn't took HR drugs for a couple of days. Afib came back and my heart reached easily 160 BPM while in afib. Then I took drugs and it all went down...

- I've had 2 touch-up procedures since then. And I still have my weekly (short, less than 2h) afib episode. I don't take meds. While in afib, my HR goes around 125-135 BPM. It never reaches 140. During my last stress test (in march), I peaked just above 140 before having some PVCs. So, I consider 140 BPM as my max HR, despite being able to go slightly above (at the risk of having PVCs).

I'll try to do some intervals while on today's ride and see if I can get above 133.

This is an interesting topic. As I have stated before I have noticed heart reactivity changes following ablation. However, never any noticable change in max rate output. Though I don't ever push myself to those limits anymore I have recently seen 172 on my HRM during a ride.

What I mean by heart reactivity is how quickly my hearts response to load changed. Instead of an instant uptick in rate. It was more like a steam locomotive. Stilk rising but at a slower rate. This however changed over time to where my heart reactivity became more normal.
To NLAMA's experience with his heart reaching a point and stopping. I to have experienced this this past year. I write about it either on my thread or in an individual post.

While on a ride I was unable to get my heart rate above 138 bpm no matter what I did. This is uncommon for me. Even on beta blockers I can get my rate to 152. The day before things were completely normal as was the next day. I can only surmise that there was something else going on in the background that my polar was not picking up. This also becomes more plausible as arrhythmias started showing back up later on as well

As to other thoughts I have had to the changes in reactivity lies in the known fact of afib remodeling of the heart. In my history of afib I have seen numbers well north of 220.

During ablation these pathways are isolated. It stands to reason that by isolating these afib pathways that we are also altering all pathways. Which could reasonably affect heart reactivity or possibly even Max HR. Again im not a specialist in the field just trying to reason possibilities.

It gets even weirder - I did two intervals and what would have had me going to 170 BPM and higher (not to mention over 45km/h) but an all out effort saw my heartrate decrease hitting a low of 90 while my speed went higher.

This screenshot shows it happening twice after I repeated the interval but not to the same degree.

It's unnerving to see your heart go down when decades of experience dictates it should be going up.

Screenshot_20201102-160551 by M, on Flickr



Edited 2 time(s). Last edit at 11/02/2020 05:21PM by NotLyingAboutMyAfib.

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NotLyingAboutMyAfib
It gets even weirder - I did two intervals and what would have had me going to 170 BPM and higher (not to mention over 45km/h) but an all out effort saw my heartrate decrease hitting a low of 90 while my speed went higher.

How did you feel during this? Did you feel normal? If you weren't tracking your heart rate would you have felt it was normal for your efforts? Was you breathing more labored than normal?

Like I mentioned. I'm guessing there is something going on in the background that a polar type HRM is not picking up.

I have experienced allot of oddball things over my many years of afib. Both prior and following ablations. Many of which made zero sense to me but might have to someone well read on the subject.

To your drop in rate I have only seen that happen once in my cycling career where effort is increasing or mostly constant and have heart rate drop off but not to that degree.

We were cycling the Blue Ridge Parkway. During the long climbs it was common to see my rate drop 10 to 15 bpm once settled into the climb.

You've got two more drops almost as deep around the 15:00 mark, and there's no significant speed change there. Looks to me like you've got a lot of variability that doesn't correlate well with level of effort.

I don't feel normal during this but I know from 10's of thousands of miles of training what to expect my HR and feel to be like for any given effort. I first started using HRMs in 1988 at the OTC and have used them ever since. There was more variability in today's ride than previous rides. Here's one from last week. Nearly flat line at 130-133 except stop light and when I stop riding, where it goes up to 140-144. (circles)

The effort to go 30km/h would normally have me going closer to 50 km/h.

ride by M, on Flickr



Edited 1 time(s). Last edit at 11/02/2020 08:31PM by NotLyingAboutMyAfib.

IMHO, and based on my own experiences over the years. I would toss the HRM to the side for a while. Exercise based only on how you feel.

Unless your trying to keep your rate below a certain point. However, I would argue that if you excercize regularly you can easily do this without a HRM. Focus on HR over the years has actually seemed to create more issues for me than not.

I agree with the general premise that HRMs may not help training and performance - e/g [www.cyclingweekly.com]

And of course - [www.cyclingnews.com]

But right now I have a problem with the way my heart is responding and for the most part I can't tell high from low or NSR from flutter w/o a device to tell me.

My first fib event had a HR of 130 and had me panicked and headed to the ER. Now I am in this range almost all of the time and can't even tell.

I understand your desire to try and track what's going on and getting to the bottom of it. But I don't think you'll be able to do this on your own.

Maybe consider having a stress test. You'll be attached to a 12 lead and they will have a better chance of capturing something. And evaluating exactly what's going on.

If you do this don't let them disconnect you right away though. Have them keep you hooked up until your heart rate drops to a normal resting rate and stays there for a while.

I had a stress test in Aug before ablation - all ok then. I can't know how it would be now. It's a mess

My heart rate is now 131 all of the time. Sleeping, riding a bike, just sitting here. On met-suc or on diltiazem. Doesn't matter.

ekg - 131 by Ma, on Flickr

Wow. High. Are you on a BB? I’m a fan of Tenormin. It lowers my hr within 30-45 minutes.

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NotLyingAboutMyAfib
My heart rate is now 131 all of the time. Sleeping, riding a bike, just sitting here. On met-suc or on diltiazem. Doesn't matter.

Then you're probably in flutter. Flutter is often resistant to rate control drugs.

In any case, you can't allow that to continue. Do you have a local EP? If so, get on the phone to them and arrange a cardioversion. If not, go to the ER. And let your NP in Austin know about this.

Thanks Carey - I am trying to do that now.

At their direction doubled up on diltiazem and rates came down - looking to get ecv and see if NSR sticks.

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NotLyingAboutMyAfib
At their direction doubled up on diltiazem and rates came down - looking to get ecv and see if NSR sticks.

I see from another post your still having issues. Stay positive. It can be a rollercoaster.