Around Christmastime 2011, I developed paroxysmal non-nodal reentrant supraventricular tachycardia, likely stemming from my maternal grandmother's history of similar cardiac problems, and underwent radiofrequency catheter ablation of the bad conducting circuit in my atrial tissue. I'm left with no fast pacing circuit to increase my heart rate on demand when I'm exercising. I know people with implanted pacer/defibrillators, and I work as medical transcriptionist and have typed a zillion of those procedures, and the things they despise about it is the problems with tissue pocket infections and interval battery replacements, requiring the site to be reopened, the equipment removed and replaced, antibiotic washout, reclosure, etc. I'll be bugging my doc at next visit to research it and determine if I can get one of these.