funny heart beat

I suffer from skipped beats, and I have for years.  I have seen two cardiologists and had lots of tests (echo, stress, halter) all of which are normal. Not even mitral valve prolapse.  I get all kinds of weird sensations.  I understand the PVC's and PAC's.  Sometimes  (and this is usually when I lie down) I will get a "surge" of about 5 to 10 fast beats in a row, then a few normal beats and 5-10 fast beats again.  It goes away in less than a minute or usually if I sit up. What is that? There is not a pause in between the fast beats and the slow beats and the best way to describe it would be that in lieu of just getting 1 premature beat, I get 5 or 10 that get stuck in that fast sequence then a few normal beats then that surge of several again.  I've described this to my cardiologist.  He just says not to worry.  I guess it would be helpful if I understood why I shouldn't worry. Can you explain this type of arrhythmia?
Thanks!

[Cleveland Clinic, MD]

Most likely you are getting several PVCs or PACs in a row.  Your doctor is right - no need to worry about it.  Best wishes.