Skipped beats/ pvcs at the start of exercise

I dont know if anyone can help me but I am absolutely devastated as to what is happening and no one can explain why.
I've had pvcs from a youngish age. I've had countless ecgs done, 4 echoes, a stress test and numerous 24 hour holters. They have never really shown anything of consequence in the echoes. Well nothing at all actually. All normal.
The holters have shown that I get 2nd degree heart block type 1 (wenkebach) during my sleep which the cardiologist said is due to my physical fitness and tight vagus nerve.
I've also had lots of bouts of sinus tachycardia and 2 ecgs that showed mild long qt along with the sinus tachycardia. Both of the ecgs were checked by cardiologists and I was told that it was computer error due to my heart going fast and that I don't have long qt.
For the last 6 or 7 years, I have trained in the gym 5 or 6 days a week. I train on the cardio equipment to a high level and have a high level of cardio fitness. I've always had one or two pvcs whilst training but not regularly and I've never been too concerned - just the odd one chucked in here and there. I normally do around 40 - 50 mins hard cardio in a session.
In January this year, I got the flu. I tested for about 3 weeks but on my first trip back to the gym, I got terrible pvcs the whole way through.
Long story short - a week later and after numerous trips to a & e, they said I kept getting sinus tachycardia and I was extremely anxious. I kept getting hundreds of pvcs a day.
I had a stress test which showed pvcs at the start that went off as I trained harder. The cardiologist was happy with the stress test and told me to ignore the pvcs.
Over the last few months, things had started to settle down. I was on a low dose betablocker to help prevent the pvcs and was back in the gym training again after a break. Training well and not getting any pvcs.
Last Tuesday it all went wrong.
I started getting skips again whilst training and have had them the same every day since.
They follow the same pattern generally (apart from 1 day) :
1. I get on a piece of cardio equipment (normally x trainer or treadmill) and start training.
2. 3 or 4 minutes in, I get a skipped beat.
3. I feel incredibly anxious but try to continue.
4. I get another skipped beat or sometimes even 2 or 3 together.
5. I get so anxious that I get off that piece of equipment (at this point, I'm around 6 or 7 mins in)
6. I go onto another piece of cardio equipment (say bike or recumbrent bike) and go really hard - high high rate maximum effort (because I'm really upset and annoyed)
7. I stay on this piece of equipment for 30 - 40 mins full blast and get no skips at all.
8. I finish with 10 mins on another piece and still get no skips.

So basically in a nutshell, I get skips at the start of my training, I change cardio machine and manage to continue the rest of the session without any then go home with terrible anxiety and wanting to cry.

This has gone on every day for a week and a half now and my anxiety with it is getting worse every day and I cannot find a reasonable explanation for why it is now happening and started like this all of a sudden.
I just keep thinking I have heart disease and about to die.
I had an echo last week and we haven't got the report back yet but I asked the technician at the time and he said "I don't see any thing too concerning".
I also had a cardiac MRI at the beginning of may and they said someone will be in touch if there is anything wrong and no one has been yet.
Is there anyone out there who can give me any indication as to what is going wrong?
I know I suffer badly with adrenaline and anxiety but I don't feel particularly "adrenalized" when I start my training.
I do know however that I do get skipped beats with adrenaline as I get them when I'm extremely upset or having sex.
Please, if ant one can help I would be so grateful because I've always used exercise as a crutch to help me get through life and my anxieties but at the moment it's causing me more anxiety on top of everything else 😭😭

I was wondering if anyone knew what causes skipped beats at the start of exercise but not during.
Think my other thread might have been a bit long!
Thanks

Hi

This is just a courtesy reply to let you know that your thread was merged with another of your threads.

Please when posting on similar topics add it onto your previous post rather than starting a new one.

It is nothing personal it is just to make it easier for people to follow your story and to give you advice as a whole.

I get skips at the start of exercise, but not during.

I've always thought it down to 2 things:

a) Heart being irritated by the adrenaline as the exercise starts;

b) Heart rate not high enough for the suppression to kick in;

Can be a bit scary. I once raced the first 8 km of a 25km running race with my heart going all over the place. But once it got really hard, it became normal.

Thanks for reply :)
It has really really scared me. I don't know if I'm just really anxious when I go in the gym or what but I don't really know what to do about it ��. I had a run of them together today. Do you ever get runs of them?
But as soon as I went on the bike, my hr was 160 + for over 34 mins and was fine. Though I was very tired when I got home.

Yes, I get runs. And I've been attached to monitors when I've had *literally* thousands in a 24 hour period.

There's a rule of thumb here.

PVCs are only clinically significant if they indicate a heart in distress (which tends to go along with structural heart abnormalities and/or heart disease). If your PVCs decrease as you exercise - in other words, if they decrease as the demands placed on your heart increase - then it's very likely they're benign.

But yes, they can be scary. I once almost fell off the back of a treadmill as a result of my heart going really quite berserk!

The first cardiologist I saw had worked as a cardiologist for the British Olympic team. He told me that the heart rhythms of those athletes were a "complete nightmare" - a function of being extremely well conditioned.

Thank for replying.
That does reassure me somewhat so thank you ��
It's just weird that they have started like this. I think that's what's scaring me more than anything.
But the brain is very good at self deception. It's not beyond the realms of possibility that I've had them start like this before and just not remember.
It's really interesting what you say about the adrenaline.
Each day this week that I have been going to the gym, I have been getting more and more anxious.
Today, I literally backed three or four times and my heart was pounding for hours before I even went to the gym.
When I plucked up the courage and went in, I went on the cross trainer and I was feeling so anxious that a couple of times I thought I was going to have to get off. I couldn't seem to really get my breathing under control either and was taking deeper breaths than I should.
Sure enough, 5 minutes in, I got a skipped beat, then another, then another.
I did my usual and got straight off, went upstairs to the bike. Got On, highest level and absolutely beasted it for 36 mins. Absolutely fine. Hr over 160. No skips.
The only difference I could tell was that I was breathing more through pursed lips (hard to describe) and my breathing was quicker but shallower than on the cross trainer.
I then got off and went on one of the hardest pieces of equipment in the gym - the stepper for 10 mins and again was absolutely Fine, no skips and my heart rate was through the roof! Lol
So what do you make of that?
Could I be subciously hyperventilating when I'm getting the skips?
Could it be the change in breathing when I'm on the other machines that makes the difference?
I am definitely breathing shallower on the other machines.
Your thoughts would be greatly appreciated x

Hey Lulu

My skips are very capricious. Before Xmas, if I walked in the afternoon, then I'd get very painful, isolated jolts. But if I walked in the morning, they wouldn't be there. Now the painful ones aren't there at all, but I get the occasional flutter.

There's no doubt about the link with adrenaline. As you say, sex is a trigger, also fear - so with respect to the latter, it could be that you've got more adrenaline floating around when you start exercising, but you burn it off as you go along.

The other thing I've noticed is that there's a musculoskeletal aspect to this stuff. I get nasty skips if I swim, even if I'm not swimming very hard. I can remember sitting on the edge of a swimming pool feeling my pulse and freaking out - must be 20 years ago now. I could never really understand why it happened when I was swimming, but not running (once I'd got going). But then I figured it out. It's the motion of my body. It's causing compression in the chest cavity, and that's irritating my heart.

Maybe it's the same with your gym machines, perhaps there's a subtle difference in the way they make your body move.

Or perhaps it's not anything you'll ever really be able to narrow down. I've been experiencing this stuff from since I was 17 years old. I've come to the conclusion that really my heart has a mind of its own. Often I have absolutely no idea why it's decided that it's going to play up for a period of time; or in a particular way.

Still bloody annoying, though! Mind you, I tend to find it more annoying when I'm not exercising. If I'm running, I just plough on regardless, with a kind of if it's going to kill me, so be it mentality! :)

You bring up some really interesting points.
I'm sure the adrenaline has a bad effect on me. Any thing that raises my adrenaline can bring on a skip. I've stopped having sex unfortunately because the skips were absolutely terrible but then again, my breathing goes out of the window too so maybe it's a combination of adrenaline and breathing there.
I wonder also if it could possibly be muscular / nerve related. I know I have a tight vagus nerve so may be that doesn't help matters.
I too have had skips swimming and it's really annoying because I love swimming. But not Every time I swim.
I suppose one of the pluses about this at the moment is that I am managing to keep going.
A few months ago, I would've just gone to bed and.stopped functioning for a while.
Ironically and luckily enough, I am actually wearing a 7 day holter at the moment which Is going back to the cardiologist tomorrow. I suspect that will tell the tale but it gets hard going especially when it affects something that you love doing so much.
We just have to keep plugging away I guess.