I hope what you're doing now is going to help you. But . . . .
Does "tried everything" include the vitamin D3 regimen that has helped hundreds of people (see the ClusterBuster Files section of this board)? Does it include busting (see the numbered files in that same section)? Is your oxygen system optimized -- high flow regulator, top-quality mask, best breathing strategies? If you were on verapamil, was the dosage high enough -- 960mg/day or more -- to actually work? Usually a mess of meds just creates a mess.