Premature atrial contractions worse after exercise...

[Sunshine989]

Hello. I am a 37 y/o female and have had issues with PACs for 15+ years. They used to occur a few times per day. Now they are occurring in the thousands per day. I average about 2-6 per minute. This suddenly occurred three months ago seemingly out of nowhere. I had an echo done and I was told structurally I have a normal heart with a mitral valve prolapse and slight regurg. I had a baby in Feb and this started 3 months postpartum. They are getting worse and worse.
I do not drink any caffeine, alcohol or consume sugar anymore.
I also noticed after heavy lifting the PACs are horrendous. Not during, but after. The skips are "harder" and make me feel like I'm choking. Has anyone else had this? Does anyone know why this would occur after exercise?? I am currently on a 30 day monitor.

[GerbyAlan]

Thanks, makes sense.  So mine do sound more like PACs.

[is_something_wrong]

I think the sensation of the PACs depends on the timing of the PAC.

PVCs often/usually have a fixed coupling interval from the previous beat. If this is, say 500 msec, they are erased when the heart rate is above 120 (heart rate 120 = 0,5 sec between beats) and more important, the sensation of all the PVCs is more or less the same.

PACs can happen early or late in the cardiac cycle. If they happen late, they are usually not noticed (confused for a sinus beat) and if they happen early, they can cause a very nasty sensation, as the ventricles are still busy working with the previous beat. If so, the atrial blood has nowhere to go (as ventricular forces are higher than atrial) so it goes backwards, causing a "punch" in the throat or neck.

To complicate things further, the PAC may or may not reach the sinus node, depending on if the sinus node is still refractory from the previous beat and where the PAC origin. And if it does reach the sinus node, the sinus node may or may not take a small pause, prolonging the time before the next beat (pause) so the next beat feels harder.

All this can cause different sensations, from fluttering to the sensation of a skipped beat to a double beat to throat sensations to absolutely nothing. It's all normal and not dangerous. A PVC usually feels like a skipped beat followed by a hard beat. A PAC can feel like almost anything weird.

And PACs can happen at any heart rate, and they often happen during or after exercise. PVCs are more common during rest (often after a stressful day).

Happy exercising :-)

[GerbyAlan]

What I meant by "it stopped on its own" ...I am referring to the palps, not the neck sensation.  That was just once and very brief.

[GerbyAlan]

Hey i_s_w, I've read quite a few of your posts and I know you're not an MD, but you seem pretty experienced in this subject, and you write well.  I'd like your feedback on my situation.

I'm 58, male, 5'6" currently 145 pounds, and fit.  Have been year round athlete for decades (running, upper body strength stuff).  I also have an LBBB, but no symptoms--except having problems this year with palps--I think they have upticked this year, but also might notice them more since finding out about the LBBB in January.  I also have no idea how long I've had the LBBB since I had not seen a doc for 30 years when I saw the cardiologist last January....I also have some lifelong anxiety issues which doesn't help, but I digress.  The main thing I'd like to ask you is whether or not I am having PVCs or PACs.  (And strange you mentioned low carb diet because the one thing that stands out about this year as far as changes I've made, is I've lost over 35 pounds since December and have cut my carbs A LOT overall.  I was a huge carb eater until this year, and still eat and drink some carbs, but not as much.)
Anyway, I thought my palps were easing off, but this morning, I had a run of them for about 30 minutes.  I was relaxing at the time (they ususally come after about 5 minutes after a workout, after the initial cooldown, but can also come at any time, especially if my thoughts are at least a bit anxious.)  I'm guessing they are mostly PACs from what I've read.  I'll feel a fluttering near the breastbone, maybe slightly to the left, but not way over at the left ventricle where I feel the heartbeat, and usually fairly high up.  Sometimes there will be heart beat pauses with these flutters, sometimes not.  Sometimes just an uneven regular beat, or it may speed up a little.  And usually when there is a pause between beats, the next beat is NOT harder than usual.  But today for the first time, when it was doing its thing, I noticed once a slight little pain for a split second near the left of my adam's apple with one of the beats.  It stopped on its own, I went out for a run and strangely didn't notice any flutter during or after today.  THere's usually at least one or two.  I guess my heart met its quota for acting up earlier.:)   Anyway, what do ya think?

[is_something_wrong]

PACs are usually caused or worsened by some sort of adrenaline excess. Often it's easier to determine the reason for having PACs than having PVCs. If the PACs are caused by excess adrenaline or other stress hormones, they often respond to beta blockers. PVCs are more "50/50" if they respond to treatment. In some cases, beta blockers even make them worse.

I have PACs myself, and at times they can flare up to hundreds/thousands a day, most of the time I have somewhere between 1 and 10 a day, when I'm taking beta blockers. My PACs respond well to beta blockers but sometimes they break through the beta blockade. It typically happens if I'm on a low carb diet (for some mysterious reason I haven't yet figured out)

Lifting weights is notorious for provoking premature beats. The adrenaline levels in your blood can increase 100 times from baseline, and the heart rate isn't as high as during aerobic exercise. Adrenaline has a half life of 2-3 minutes, so quite some time after the lifting, you can have very much adrenaline in your body. Which provokes PACs.

It's not dangerous at all, but it can feel really horrible.