I had some PSVT several years ago. My heart rate would jump from 50-60 to 150 or higher. This would happen several times a day, lasting 15-20 seconds. Doctor's recommendation was ablation or beta blockers. A friend told me about taking a magnesium supplement called Slo-Mag, and a sublingual 2500mcg B-12 supplement, for example from Solaray. My symptoms diminshed over a week and disappeared. I had one reappearance, and I doubled the magnesium dosage for a week and it went away again. Much better than ablation or beta blockers.

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salmon - not because I'm a fish

One of the best discussions of the issue of arrhythmias in athletes I have read

The Haywire Heart

https://www.velopress.com/books/the-haywire-heart/

Thanks I'll give it a try. I eat a ton of magnesium-containing foods so feel it's a long shot but worthwhile if I don't have to get an ablation or go onto beta-blockers.



Yes, I read this book -- it suggests de-training as first line therapy but doesn't really provide much in the way of guidance. Any ideas? I'm thinking 50-70% reduction in volume and intensity?

Have you thought of contacting Dr Mandrola directly? He used to post on ST and so he may respond directly, but you also may be able to find a way to contact him directly.

I have been following his blog posts for years. Some doctors give the impression they think they know everything; he is at pains to emphasise that he continues to learn and is sceptical of certainty. He writes well too.

Seems a straight up decent, open-minded and well-intentioned guy who might be prepared to offer advice if contacted.

I would consult with an electrophysiologist (physician who specializes in arrhythmias). Patients with longstanding tachyarrythmias are actually at risk of having decreases in the systolic (contractile) function of the heart, something called tachycardia induced cardiomyopathy. In order to make informed decisions about treatment, I would work with a cardiologist, an echocardiogram may be beneficial. Often, with treatment of the tachyarrythmia, tachycardia induced cardiomyopathy will resolve and improve. It may seem obvious, but you should seek medical advice from a qualified professional, not just a bike mechanic and web forum. Some arrythmias are amenable to treatment with electrolytes, e.g. magnesium, while others are more resistant. On the spectrum of invasiveness in medicine, ranging from expectant management (wait and see...) to open heart surgery, SVT ablation falls in the middle. Typically done in a cardiac catheterization lab, the ablation is done by catheters placed in the groin vessels. Can be done with general anesthesia or deep sedation (like a colonoscopy).

I've been living with one for close to 30 years now. HR kicks up to 235+ while exercising. Detraining does help because mine is exercise-induced, so duh, when I exercise less it happens less. But I prefer exercising, so I just manage it as best as possible - limit caffeine and chocolate before workouts, don't exercise on full stomach, do the cough, eyeball and other tricks when it hits mid-workout. The multiple cardiologists I saw preferred this to meds, although I'm probably due for another appointment as I age up.

There are a lot of different causes for SVT though, and some can respond very badly (y'know, like death) to exercise. Don't take advice from ST, take it from your doctor.

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I've had it/have it (?). I never noticed it previously but it was picked up through various tests and during a stress test.

I had an ablation two years ago but he wasn't sure he got it as it would disappear every time he got close to zapping it.

After the ablation I had three episodes within a year in which I did notice it, each one lasting 2-3 seconds each, two during a hard effort (170 bpm+) peaking up to 218-225ish (according to hrm), one while at rest.

That's about it for me. I originally got some tests done to feeling "skipped beats" more and more frequently, until the point where I even felt it in a race two different times which caused me to sit up and reduce the effort.

Currently I try to make sure I don't push through fatigue too much, as it's my personal opinion that that was part of the original issue. I also try to manage anxiety better and take note of when life has the potential to cause overreaching in training rather than just monitoring training on its own. This has led to lots of skipped rides, and trying to take more 2-3 day blocks off, but overall things seem much better.

With the ablation I took a good 5 months off, and then I took another 6 months off last fall/winter, but I am now at a fitness level I had 4-5 years ago and haven't had any issues in the last 8-9 months. I think I'll probably take a couple of weeks off here pretty soon and then build up again for next year.

For whatever my experience is worth, I had SVT episodes around age 39. Some while exercising, and some even while laying in bed, where my heart rate would jump to 250ish. Had a successful ablation in the cath lab as described above, and I haven't had an episode since, in 10+ years.

I started having these in my early-mid 30s. one or 2 a year then all the sudden I started having a couple a week until I wore the event monitor of course lol. They would only happen either during exercise or right after. I had an ablation done and have had 2 in the last 3 years.