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Excitable cells

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Re: Excitable cells

#31

Post by UncleOxidant »

elric wrote: post #18
eknkc wrote: post #14

I have frequent ectopic beats that I feel as a flutter / heavy beat on my chest. The doc says it won't kill me but it is extremely uncomfortable at times. This has been a great material to learn about the inner workings of heart cells. BTW Here's an ECG from my Apple Watch showing 3 such beats (you can't miss them): https://link.ekin.dev/l1Vc3Gdf If you happen to have these, just get checked out by a cardiologist. Th…

Many (most?) people get ectopic beats, but the threshold for noticing them seems to differ. Being stressed/anxious makes them more noticeable. There's a self-reinforcing feedback loop: the more you notice them & worry about them, the easier you will notice them ... The thing about arrhythmias is that they can only cause damage while they're happening, but ectopics are only a problem for a single beat, which is not go…

> Many (most?) people get ectopic beats, but the threshold for noticing them seems to differ.

This. Some of us have very high levels of proprioception. I can feel my pulse just by sitting quietly - I don't need to put my finger on my wrist to take it. Same with ectopic beats, I definitely feel them. And I find that there's a cycle to it - as you say there's a feedback loop: feel ectopic beat, become anxious, more ectopic beats, more anxious, etc. Then I have to try to actively forget about them. During those feedback times I'll have many ectopic beats / day (many per hour, even), but then some days later I'll realize I haven't had any for a while and I might go for weeks without noticing any.

Re: Excitable cells

#32

Post by pscanf »

TheJoeMan wrote: post #16
pscanf wrote: post #9

Exciting simulations! :) And an excellent explanation. From time to time I get episodes of sudden tachycardia¹. It's a very strange feeling: one second everything is fine, the next my heart jumps in my throat and starts beating at 230 bpm (not a typo). After a while, just as quickly as it came, the tachycardia goes away and I'm back at whatever HR I was before the trigger. If it doesn't go away by itself, breathing i…

Do you drink a lot of caffeine? A family member had this occasionally with no family history of issues, and the cardiologist had them wear a portable EKG for a few days that synced with an Android phone, with not much results. Finally the family member cut down from 4 espresso shots a day to just 1 cup of brewed, and the issue hasn't returned.

Yeah, several cups of tea per day. I also recently had that test done, but nothing emerged as nothing occurred during the 24 hours I was monitored. Just like I expected, actually, as fortunately those episodes are very rare for me, not enough to warrant drastic lifestyle changes. (I can't give up my tea! :D )

Re: Excitable cells

#33

Post by pscanf »

papascrubs wrote: post #13
pscanf wrote: post #9

Exciting simulations! :) And an excellent explanation. From time to time I get episodes of sudden tachycardia¹. It's a very strange feeling: one second everything is fine, the next my heart jumps in my throat and starts beating at 230 bpm (not a typo). After a while, just as quickly as it came, the tachycardia goes away and I'm back at whatever HR I was before the trigger. If it doesn't go away by itself, breathing i…

I have the same condition. I was diagnosed at a very younger age with Wolff-Parkinson-White syndrome. It might be worth looking into. https://www.mayoclinic.org/diseases-conditions/wolff-parkins...

Fortunately I don't think it's WPW in my case. Or at least, my cardiologist never mentioned it, so I assume it's some other condition that has similar symptoms.

Re: Excitable cells

#34

Post by PaulHoule »

dcminter wrote: post #15
pscanf wrote: post #9

Exciting simulations! :) And an excellent explanation. From time to time I get episodes of sudden tachycardia¹. It's a very strange feeling: one second everything is fine, the next my heart jumps in my throat and starts beating at 230 bpm (not a typo). After a while, just as quickly as it came, the tachycardia goes away and I'm back at whatever HR I was before the trigger. If it doesn't go away by itself, breathing i…

A couple of years ago I woke with a minor headache that I ignored for various reasons all day, then skipped lunch as I had an important meeting later and lots to do ahead of it, and the headache got progressively worse. Just before the meeting I felt nauseous, threw up, and then started having the feeling of palpitations in my chest. I've always had them from time to time - that feeling that ones heart has skipped a…

I fainted when I was an exercise class. I'd had too much to eat before then, my digestion was pretty slow then, also it was a crazy hot day in a building with a pool (high humidity) and an old HVAC system. Didn't help that I had a crush on the instructor and was trying even harder because of that.

Woke up on the ground feeling very relaxed. Got a medical workup that checked a lot of things, they had me wear a Holter monitor for a month. In the last 30 minutes of the study period they caught five bad heartbeats of A-Fib when I was sleeping. Funny one of my evil twin's schemes went south around then and I (we?) were feeling really bad about it. My cardiologist told me that the threshold was one bad heartbeat so I have A-Fib and have a risk of strokes, he recommended that I take a baby aspirin as it has a mild blood thinning effect.

Around the beginning of the next year I developed a deep vein thrombosis which got cleared up with Eliquis, a blood thinner. The emergency room referred me to my primary care doc who ran all sorts of tests and couldn't find a reason for the DVT so he decided to keep me on Eliquis indefinitely, the cardiologist figured that covered the A-Fib so I dropped the aspirin because the combination could cause excessive bleeding.

I have one of those credit card Kardia EKGs and haven't seen an A-Fib episode yet. For the decade before I got that workup I did crazy amounts of cardio (helped me stay sane under incredible pressure) and around the time my evil twin was out I was getting up in the morning before sunrise, hiking 6 miles, going to the gym during the day, going out in the evening and hiking another 6 miles. My cardiologist says I have "Athlete's heart" with an abnormally low resting heart rate (drops below 50 at night when I get a good night's rest) and I shouldn't do more than an hour of cardio a day, so I don't.

Re: Excitable cells

#35

Post by pscanf »

dcminter wrote: post #15
pscanf wrote: post #9

Exciting simulations! :) And an excellent explanation. From time to time I get episodes of sudden tachycardia¹. It's a very strange feeling: one second everything is fine, the next my heart jumps in my throat and starts beating at 230 bpm (not a typo). After a while, just as quickly as it came, the tachycardia goes away and I'm back at whatever HR I was before the trigger. If it doesn't go away by itself, breathing i…

A couple of years ago I woke with a minor headache that I ignored for various reasons all day, then skipped lunch as I had an important meeting later and lots to do ahead of it, and the headache got progressively worse. Just before the meeting I felt nauseous, threw up, and then started having the feeling of palpitations in my chest. I've always had them from time to time - that feeling that ones heart has skipped a…

Yeah, the first time it happened (about 15 years ago) I thought "that's it, I'm dead". Heart things are unnerving indeed! Best of luck with your AFib!

Re: Excitable cells

#36

Post by ggambetta »

eknkc wrote: post #14

I have frequent ectopic beats that I feel as a flutter / heavy beat on my chest. The doc says it won't kill me but it is extremely uncomfortable at times. This has been a great material to learn about the inner workings of heart cells. BTW Here's an ECG from my Apple Watch showing 3 such beats (you can't miss them): https://link.ekin.dev/l1Vc3Gdf If you happen to have these, just get checked out by a cardiologist. Th…

I had some of those, verified by ECG. Cut down on coffee a bit, they went away.

Re: Excitable cells

#37

Post by eknkc »

elric wrote: post #18
eknkc wrote: post #14

I have frequent ectopic beats that I feel as a flutter / heavy beat on my chest. The doc says it won't kill me but it is extremely uncomfortable at times. This has been a great material to learn about the inner workings of heart cells. BTW Here's an ECG from my Apple Watch showing 3 such beats (you can't miss them): https://link.ekin.dev/l1Vc3Gdf If you happen to have these, just get checked out by a cardiologist. Th…

Many (most?) people get ectopic beats, but the threshold for noticing them seems to differ. Being stressed/anxious makes them more noticeable. There's a self-reinforcing feedback loop: the more you notice them & worry about them, the easier you will notice them ... The thing about arrhythmias is that they can only cause damage while they're happening, but ectopics are only a problem for a single beat, which is not go…

Apparently everyone gets them but the burden (% of beats being screwed up) is important. A high burden for prolonged periods means damage accumulation.

I had 2 24 hour monitors and one caught 700 eptopic beats in a day. Another couple months later, 15.000 in a day. The second one was a concern for the cardiologist. She ordered a couple more tests, started beta blockers asked for diet changes.

I still have a high burden as I can feel them but whatever..

Re: Excitable cells

#38

Post by johannes_ne »

Thank you for all the kind responses.

I also want to make a similar article, where I calculate an ECG for the simulation, and then make and explain the changes necessary to make the ECG look realistic. A main challenge will be that the depolarization has to happen very fast relative to the repolarization, which may be computationally difficult for a cell-based simulation.

Re: Excitable cells

#39

Post by UncleOxidant »

rdegges wrote: post #19
eknkc wrote: post #14

I have frequent ectopic beats that I feel as a flutter / heavy beat on my chest. The doc says it won't kill me but it is extremely uncomfortable at times. This has been a great material to learn about the inner workings of heart cells. BTW Here's an ECG from my Apple Watch showing 3 such beats (you can't miss them): https://link.ekin.dev/l1Vc3Gdf If you happen to have these, just get checked out by a cardiologist. Th…

I had something similar for many years (triggered by an episode of afib brought-on by triggering my vagus nerve). The one thing that has helped me fully get rid of these (after YEARS of trial-and-error) was getting onto beta blockers (Propranolol). These have COMPLETELY gotten rid of my ectopic beats and also helped me deal with the health anxiety. If you ever want to talk, feel free to hit me up (contact info in pro…

> an episode of afib brought-on by triggering my vagus nerve

I get ectopic beats when I've got trapped gas in the stomach. Sounds weird, but generally when I get them I realize I need to stand up (because I've usually been sitting with bad posture which leads to the trapped gas) and have a large belch and then it calms down. I mentioned this to my doc and he said it was Roemheld syndrome ( https://en.wikipedia.org/wiki/Roemheld_syndrome ) which is vagus nerve-related.

Re: Excitable cells

#40

Post by [deleted] »

UncleOxidant wrote: post #39
rdegges wrote: post #19

Earlier quoted context omitted.

I had something similar for many years (triggered by an episode of afib brought-on by triggering my vagus nerve). The one thing that has helped me fully get rid of these (after YEARS of trial-and-error) was getting onto beta blockers (Propranolol). These have COMPLETELY gotten rid of my ectopic beats and also helped me deal with the health anxiety. If you ever want to talk, feel free to hit me up (contact info in pro…

> an episode of afib brought-on by triggering my vagus nerve I get ectopic beats when I've got trapped gas in the stomach. Sounds weird, but generally when I get them I realize I need to stand up (because I've usually been sitting with bad posture which leads to the trapped gas) and have a large belch and then it calms down. I mentioned this to my doc and he said it was Roemheld syndrome ( https://en.wikipedia.org/wi…

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