What are the risks are associated with an implantable cardioverter-defibrillator?

AICD: First of, this is a life saving device for individuals needing one! as this is inserted using surgical techniques, risks associated are bleeding, infection etc... Once implanted the device or leads can malfunction or administer an inappropriate shock etc.. Bottom line: very high benefit (stay alive), low risk.

Tiny risk: An icd is indicated for people who are judged to be at significant risk for sudden cardiac death. Not implanting an icd in this context confers a far higher risk than the procedure which, itself, is a relatively simple and low risk minor operation done with sedation and local anesthetic. There are small risks of bleeding, blood clot and infection.