Recently diagnosed with Inappropriate Sinus Tachycardia.

Hi, recently diagnosed with IST (22M). I’ve noticed high HR when standing and exercising (115-150bpm) for 7 months, which I originally thought was POTS but I’ve been told it’s IST.

I’ve been put on Ivabradine, 7.5mg daily (in halves), but I am concerned as my resting/ usual heart rate is around 65-80 bpm. Is this not a massive contradiction to the diagnosis?

I was diagnosed one of the top Cardiologists in my country so I am trying to have faith.

Thank you