23 Comments
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Edward's avatar

Tremendous! Thank you! a lot of take aways!

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RHG Burnett's avatar

As a patient, I just want to pop in to say that the Zio Patch was a game-changer in my diagnostic journey. Prior to its use as a diagnostic tool I had been fitted with 12 and10 lead halter monitors, which are cumbersome, and cannot be worn for much more than a couple of days. In 2017, I was monitored for the first time using the Zio patch and the amount of freedom to do the exercise I normally do, to fully participate and life my life the way I normally would. This supported clear diagnosis in a way that was not possible when you have multiple leads snaking across your body.

As someone with a LBBB, and intermittent PVCs, the Zio is an amazing diagnostic tool. I am still surprised it is not utilized more.

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Lisa Saunders's avatar

Years ago in my late 30s I had PVCs. Normal echo and since they only happened at rest, cardiologist said they were benign and not to worry. Thankfully never had to give up my beloved cups of coffee;)

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RayDar's avatar

Good article. I think one of the missed items may be what we tried to use in clinical trials for determining what an abnormal amount of PVCs actually are in “otherwise healthy subjects”. We set 2% and 5% cutoffs to determine that more thorough diagnosis is needed when they exceed 5%.

Coming from an ion channel group in pharma that looked to develop the next generation anti-fibrillatory drug, and working for Bristol-Myers Squibb who’s drugs were killed by the CAST and SWORD studies, I can attest that crushing PVCs due to symptoms alone (since we now now that, in isolation, they are largely harmless) is NOT warranted. My personal experience as a lifelong fit pharmacologist is that the autonomic nervous system play an outsized role in many people with frequent, benign PVCs. If I exercise regularly, my PVCs are minimal. When de-conditioned, even after one week, they come back. It’s my proof of the long-held pharmacological principle of ying-yang. We should always consider the autonomic nervous system when evaluating PVC.

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Hanson Quickel's avatar

I like much of what you have to say, but I can testify from 13 years of experience that low magnesium levels (and not just potassium levels) will bring about ectopic beats. I need at least 6 to 8 hundred mg of magnesium daily to ward off PVCs and PACs. You write that stress and anxiety can cause ectopics, but fail to mention that stress and anxiety also burn magnesium. I'm less concerned about the quacks you name than the fact that doctors like yourself receive next to zero college education about minerals and what they do. I would suggest you pick up a book by Dr. James Dinicolantonio. The Mineral Fix is something all doctors should have on their shelves.

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The Skeptical Cardiologist's avatar

"I'm less concerned about the quacks you name than the fact that doctors like yourself receive next to zero college education about minerals and what they do."

I did get a Masters degree in organic chemistry before heading off to med school. Do you think i'd be a better physician if I had gotten that education in inorganic chemistry?

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Hanson Quickel's avatar

Well, inorganic chemistry does include minerals! Here's the bottom line. When my ectopics started long ago the GP put me on metoprolol, which made me worse. Then my cardiologist tried flecainide, which (after several weeks) gave me extreme chest tightness. Because my blood test magnesium numbers came back at the low end of normal, magnesium was never suggested, but I did my research. Simply put, magnesium was and still is my savior. I fired my GP after he said to me, "The cause of your problem isn't important, only the treatment." If I have ectopics now, I know it's because my magnesium levels are low. If only one of my doctors had mentioned this possibility.

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Lisa Saunders's avatar

800mg magnesium is half a colonoscopy prep, kudos on your regular bowel movements.

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Hanson Quickel's avatar

No constipation here, but I don't use mag oxide or citrate either so I'm not Mr. Poopy Pants.

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Kathleen Talafuse's avatar

Which magnesium compound do you use?

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Hanson Quickel's avatar

I prefer mag glycinate.

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Kathleen Talafuse's avatar

I’ll try that and see how it works for me. My doctor told me mag oxide was the way to go.

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Hanson Quickel's avatar

Your doctor needs to research magnesium. Mag oxide has the worst absorption.

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Kathleen Talafuse's avatar

Thank you.

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paul michael rivas's avatar

Is there any recent evidence that very frequent premature beats could be an atrial clot risk , and therefore a stroke risk?

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Sobshrink's avatar

Not long ago, I noticed my heart rate bpm varied wildly when I was standing, walking, or exercising, but never while sitting. This was a very new phenomenon. I sometimes had palpitations. I've done cardio for decades so always had a low heart rate. (Yes, I'm getting old). My NP who is my PCP wasn't concerned about it at all, but I was also fatigued, so I decided to order a Kardiamobile on my own, which showed no Afib (YAY). I decided to do the 10-minute consult with one of their cardiologists about the extreme fluctuations in my HR that happened very quickly. He just called it "heart rate lability" and told me to tell my PCP to order a Holter and a stress test, which she did. My Holter showed VE's (under 1%) which I guess are basically the same as PVC's, and also SVE's (under 1%) which I guess are also not serious. My stress test was good although never got HR up to expected level because of my fitness. My PCP still could not explain the wild fluctuations in HR to me, so she sent me to a cardiologist for a consult. Luckily the cardiologist told me no further testing or interventions were needed because the results showed no increased risk of stroke or heart attack. She explained the extreme variability in HR was an artifact based on estimating bpm by extrapolating from a brief time sample, and the extra beat made it look like tachycardia when it really wasn't. I lucked out on getting a good cardiologist who set my mind at ease and didn't recommend unnecessary tests or interventions. It would be nice if PCP's understood more about this, especially when they have lots of older patients (which she does). I hope they subscribe to your Substack! Thanks for a good explanation of a common problem. As more and more folks get smart watches, I think more education is needed!

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Laurie Longoria's avatar

I bought an Alivecor Kardiamobile 6 lead in 2021 because I have a history of PVCs but I was having long runs of symptomatic arrhythmia that I suspected was AFib. My cardiologist had dismissed my symptoms as anxiety. Why do men do this? I’m a post menopausal woman and not the anxious type at all. Needless to say, I was able to catch my Afib in action.

Here I am in 2025, on blood thinners & 2 cardiac ablations under my belt. My paroxysmal AFib is stubborn once it gets going. I’m forever grateful to have found the Kardiamobile. It’s simple to use and set up with the app, pocket sized, affordable, and easy to carry in a purse or wallet.

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Sobshrink's avatar

Go to a female doctor. That's what I did! :) I hope you remain stable and healthy!

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Laurie Longoria's avatar

Unfortunately, I live in a healthcare desert where specialists are limited. We have few/no female specialists depending on the type of specialty. I do have a much better cardiologist now after having switched several times. Every single one of my doctors/specialists retired during Covid including my PCP, dentist and eye doctor.

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Sobshrink's avatar

Yikes! Sorry to hear that. Glad to hear you seem satisfied with your current cardiologist. All the best!

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laurene mccune's avatar

My pvcs led me down a path of diagnostics resulting in a stent being placed . mid lad 90% bifurcation . But pvcs still remain . Sometimes with a vengeance !

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medstudent's avatar

such a great primer on this very common issue - thank you!!

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