Thanks everybody. Massage is a good idea.

Dx: PSVT probably AV nodal reentrant tachycardia.

Tx: catheter ablation. Snake a tube into whatever artery they like best. I guess they tease my heart to set it off so they can locate and zap the naughty bit out.

Good news: I get to be knocked out.
More good news: 95% success rate
However: Possibility of stroke or death (Hardly ever happens, but when it does it's really bad.)

Best bit: My DD the med student got permission to watch. Not sure if it works with her schedule yet.

I think the whole thing is pretty enormously cool--except for the part about it taking place in my very own, one and only body.