It's possible, but the risks are heavy.
-Losing the money you spent on buying it, if you fail.
-Permanent brain damage, if your dose is really heavy, but not heavy enough to kill you.
-If you survive, you have to choose between addiction or going through withdrawals, neither are exactly fun.
In my opinion, your best bet is to incorporate heroin into other ctb methods, such as injecting a bunch of heroin and then passing out with a rope around your neck.
That way you hang to death while your consciousness is in the warm and euphoric heroin dimension.
But, OD with only heroin is still possible, if you really insist, just be aware of the risks.