Hey. I am a 25 year old female who has smoked for about 8 years. i recently stopped and ive had panic attacks and palpitations for about a year now maybe a little over a year. I had all the test done and they all came back fine. until i wore a heart monitor for 2 weeks and during that 2 weeks they caught one episode of Nonsustained Ventricular Tachycardia. it only lasted about 3 seconds and i think they said the BPM was 140. what im wondering is should i be worried that this is life threatening? im going in for a cardiac MRI the 28th of this month but im still so scared to wait that long because i DO NOT WANT TO DIE! please help me to feel better about what is going on with me.