I am nearing my one year anniversary of successful third ablation for Atrial Tachycardia. I have noticed an increased incidence of IST or Inappropriate Sinus Tachy lately after being off all meds and having no issues for about 6 months. Now my mind always returns to the past and wondering if it is related or some harbinger of badness. Anyone else have anything similar?

IST has no relation to afib or flutter that I'm aware of, and I doubt it's a harbinger of anything seriously bad.

How fast is the tachycardia and how long does it last?