The first time it happened to me I was about 20 and thought I was dying! Sometimes it was as if the blood was starting to drain out of my head, then I would start seeing spots, then I would collapse like you said. It was very different from panic or anxiety attacks...I would just be sitting and then would get that funny feeling and start to pass out. I learned to cough or hit my chest to help get the rhythm back and when I did start to lose consciousness it always started up again on its own. Learning not to react with fear and anxiety is the biggest challenge.
Over the years I had ECGs, ultrasounds, etc and at various times they found a heart murmur, left ventricular dysfunction with mitral valve prolapse, premature ventricular contractions (PVCs as mentioned above), low ejection fraction and eventually congestive heart failure (which I am convinced had to do with lyme or a co-infection).
What helped me was learning biofeedback based on heart rate variability training. Many hospitals and clinics do this and it basically teaches you to breathe properly to balance your sympathetic/parasympathetic nervous system.
When I get a cold or virus of any kind the heart problems flare up again, but I don't have to have pretreatment for dental work and in between my heart looks fine - no permanent damage in spite of the severe bout with congestive heart failure.
I still have palpitations several times a day and often at night - sometimes it feels like my heart is pounding against my ribs, sometimes the rhythm is totally off for several minutes and sometimes I start to black out. But I just ignore it now and figure my brain will sort it all out and get it back on track.
Your monitor will help diagnose the exact nature of the palpitations and they'll probably do an ultrasound to rule out any heart disease, but I also believe it's very common to tick-borne infections.
Jan
[This message has been edited by janinco (edited 21 October 2004).]