I don’t want to bore you guys with medical info but for those who want to know more about IST (inappropriate sinus tachycardia) which is what my Dr. said I have. So bascially this is for my family who wants to know more. IST is an uncommon type of cardiac arrhythmia, within the category of supraventricular tachycardia (SVT)–which I have. The mechanism of the arrhythmia primarily involves the Sinus Node and peri-nodal tissue and treatments are in the form of pharmacological therapy or Catheter ablation are available, although it is currently difficult to treat successfully. So basically it’s a condition in which an individual’s resting heart rate is abnormally high (greater than 100 beats per minute), their heart rate increases rapidly with minimal exertion, and their rapid heart rate is accompanied by symptoms of palpitations, fatigue, and exercise intolerance. IST is not associated with an abnormal electrical pattern on the ECG. The heart rhythm in IST appears to arise from within the sinus node, the cardiac structure that generates the normal heart rhythm. Patients with IST are hypersensitive to adrenaline, such that a little bit of adrenaline (like a little bit of exertion) causes a marked rise in heart rate. There is evidence that the sinus node itself has structureal changes. But much other evidence suggests that a more general dysautonomia is present in these patients. (This would explain why symptoms most often seem out of proportion to the increase in heart rate.) It is the notion that the sinus node itself is intrinsically abnormal that has led electrophysiologists to resort to ablation of the sinus node as a treatment for IST.
I hope that wasn’t to medical for you but it’s a synopsis of what it is.
