How Long Should Methamphetamine Be Avoided Before Going In For An Angioplasty?

I am a methamphetamine addict. I use several times daily about a 1/4 oz. a week. I may have to go into surgery due to at least one and maybe more obstructed arteries for angioplasty. What are the risks of undergoing general anesthesia as a meth addict and hos long should one abstain from using given my level of use if that were necessary.