i am an 18 year old male. 6 ft tall and 10 stone in weight. i have been having problems with my heart for several years. i have random episodes of palpitations and chest pains. i have been to the hospital twice where they carried out two ECG s on both occasions. each time they found an abnormality with the first but nothing with the second. but by this time the feeling had gone. they carried out blood tests but found nothing wrong. the first time i ever had this was in spain in 2007. i had just been bought the biggest glass of juice i d ever seen ans whilst i was sat drinking it the feeling came on. i ve had it random ever since. its normally a heavy and dull pain but last night it was different. i had been drinking alcohol. i hadn t drunk as much as i normally would have but the pain was a sharp stabbing feeling. and i found it really hard to find my pulse. i found it on the left side of my chest and it felt as though my heart was beating an extra beat. where it should beat twice, it was beating three. so i called an ambulance. after 20 minutes waiting for the ambulance it arrived and they immediately hooked me up to the ECG machine in the ambulance and took me to hospital. on the way i noticed on the machine that my heart rate was at between 110-190. it was jumping up and down extremely rapidly. but i asked the paramedic if this was normal and he told me not to worry. the doctor in A&E says it may be pericarditis. but after checking the symptoms i noticed that they don t really fit in with what i had. it seems to be only when i drink alcohol now that i get this feeling. i have been avoiding caffeine completely since the last time i was in hospital in december 2009 and i hadn t had another episode till last night. and i had been drinking alcohol since then without an episode. but last night i had a few glasses of coca cola throughout the night. which i would normally avoid. i had been doing backstage work for the local dramatics club so i had been doing more manual labour than i would normally. i find that i get extremely out of breath from doing the slightest thing. if i run up a small flight of stairs my heartrate will jump up extremely high and i ll be out of breath. i hope you can help me with this because i am quite worried about it