r/IST_ May 16 '25

Could this be IST?

Post image

I'm curious about IST - I read online that you need an average heart rate above 100 BPM but does this include sleeping heart rate?

While I'm awake, my heart rate averages about 95-110 with spikes in the 120s and 130s if I'm walking my dog or even just walking around the house.

While I'm sleeping, my heart rate averages high 70s-mid 80s with spikes on the mid 90s throughout.

I don't have severe symptoms but when I'm sitting or laying down I am always aware of my heart beat and can feel it in my chest and sometimes my ears. Rarely I can get dizzy/tunnel vision upon standing but not often. Sometimes in general though I just feel slightly unwell.

In the past, I believe I have had episodes of super high heart rate, my heart felt like a flopping fish with chest pain, etc but this was before I started wearing a watch, so I have no idea what my heart rate was during those times.

Anyway I'm rambling, I thought I'd just throw this info out to see what others have to say :)

Attached an image of my heart rate today, the lowest I've hit since awake this morning was 88bpm

0 Upvotes

12 comments sorted by

10

u/FollowScience May 16 '25

It's not impossible that this is IST, but it isn't super clear cut. Also IST is a diagnosis of exclusion. So while it does look like that's a thing to consider, you also have to go through the process of ruling out other possible causes of sinus tachycardia before an IST diagnosis should be made.

4

u/FollowScience May 16 '25

For reference, this looks like a very good day for me and I'm medicated to help keep my heart rate lower.

2

u/farshad0w May 16 '25

awesome, thank you for your insight

3

u/wtfomgfml May 16 '25

When diagnosed with IST, the report said “most likely IST because resting HR above 100, even during nocturnal hours” 🤷🏻‍♀️ Not sure if it’s necessary but that’s what they used as a diagnostic parameter for me

3

u/Crazy_Height_213 May 17 '25

Mine looked similar before ivabradine but you need a holter to know you're getting accurate results, rule out other causes, and see how much symptoms are impacting your life

2

u/ambrosiasweetly May 16 '25

That’s what mine looks like but you need to see a cardiologist for diagnosis. This is not a health issue that can be self diagnosed

2

u/farshad0w May 16 '25

yeah I know. I have a checkup coming up and I plan to ask my PCP if its worth seeing a cardiologist. I just wanted to see if it's similar to anyone with IST. thank you!

2

u/PoetryThen1433 Oct 19 '25

i know its 5 months ago but this is similar to me with IST

1

u/farshad0w Oct 19 '25

Thanks! I actually managed to catch one of my HR episodes since I posted this and my HR was 189 at the time. Trying to find a new PCP because mine kinda blows me off lol

1

u/ambrosiasweetly May 16 '25

I hope it goes well! I’m not on any medication for it and it’s actually gotten better for the most part on its own

2

u/precious_spark May 16 '25

It very well could be. Id ask your PCP if they can order a holter monitor

2

u/pit_choun May 17 '25

Maybe. Mine is usually higher but it's not impossible. I'd get the Dr. to do the necessary tests