An implantable cardioverter-defibrillator (ICD) is a device designed to quickly detect a life-threatening, rapid heartbeat coming from the bottom chamber of the heart. It converts the abnormal rhythm back to normal by delivering an electrical shock to the heart.
Review Date 7/25/2018
Updated by: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.