Months and months of being seen by numerous doctors I was finally diagnosed with Paroxysmal supraventricular tachycardia. I haven't had many episodes, but when I do there pretty scary. When I have an episode I always do the valsalva maneuver. This consists of holding the breath and straining or coughing while sitting with the upper body bent forward. Splashing ice water on the face has been reported by some people as helpful. Avoid excessive alcohol,smoking, and caffenine. There are a lot more things you can do...but these are just the basics. Do a search on the web there is ton's of info about it! Hope this helps