Is active cocaine or methamphetamine use a contraindication to implanting defibrillators?   

As a general principle, I do not think that a potentially life-saving intervention should be withheld in patients with substance use disorders (including tobacco, alcohol, cocaine, methamphetamine, or even IV drugs) unless the risk of the intervention outweighs the anticipated benefit. Further, I be...

I would say a relative contraindication (more so for primary prevention). This is based mostly on the risk of poor follow up which would increase the risk of poor outcomes we avoid with regular management like inappropriate shocks, battery management, etc.