Heart palpitations can be caused by many things. Sympathetic nervous system stimulation may cause it (a perfectly normal/expected consequence is heart palpitations) - for example, when you are up on stage in front of a huge crowd or when someone randomly honks at you when you aren't expecting it. Or it could be something more leery. Please note that heart palpitations is an abnormal *awareness* of your heart beat. Chances are if you are not symptomatic in any other way (eg. chest pain, fatigue, activity intolerance, episodes of fainting or passing out, etc.) you probably have nothing to be too concerned about. It also depends on the medication you are taking - are you on cardiac medications or anything that could disrupt your fluid and electrolyte levels (something that increases or decreases gastric motility like Lomotil or a laxative of some sort). There are meds that can cause cardiac side effects, but not all of them do.

I would say wikipedia is probably not the best resource for medical information. It might be better to check WebMD if you are going to look on the web. Even better would be talking to your doctor or seeking a second opinion if you are truly concerned. But it is just a suggestion.

Good luck!
~BxD