well, either way, it wasnt heroin.
as for low bp/pulse?
prolly mixed harsh with ketamine.
ketamine is a animal antibiotic, but is taken mainly at raves, (from my own experience)
either taken AS ketamine, or sold under various names, speed,e,coke, etc when it actually is ketamine.
ketamine slows down your whole system, heart rate, bp, metabolism, breathing. EVERYTHING.
some people have apparently tripped out from ketamine.

dunno for sure, but my cash is on that.