Anyone with Inappropriate Sinus Tachycardia (IST)?

I was diagnosed with IST about 10 years ago. I honestly thought I was having a heart attack it felt so weird. I’m on Verapamil daily to help keep my heart rate at a more normal level. Without meds, my resting heart rate is anywhere between 125-160. With the meds I’m usually at around 110. They cannot figure out why my heart rate runs so high. The do think I had a very tiny heart attack last year. It’s scary. I don’t have any issues with my blood pressure. It’s always on the low side of normal. I’ve had stress tests, holster monitors, etc.

i was told i have that! (i got told that along with my pots diagnosis!) i don’t really have blood pressure changes so i think that’s what it was mostly about for me. but if your heart rate is changing with the tilt test… that’s the criteria! 😊