I started having high natural heart rate and palpitations in February of 1997 at the age of 16, and after nearly 9 years of random diagnoses, such as Atrial Fibrillation, SVT, Panic Attacks etc. I finally have a doctor who was able to give me a straight answer. I have IST/POTS (Inappropriate Sinus Tachycardia/Postural Tachycardia Syndrome). So I've been told a few things, increase my sodium intake, water intake, continue exercising, stay on my heart meds to regulate my heart rate and blood pressure, and basically "hang in there". Anyone else have any suggestions for the new person??