Skip to Content
Home > Wellness > Health Library > Implantable Cardioverter-Defibrillator (ICD)
An implantable cardioverter-defibrillator (ICD) is a small device
that uses electrical pulses or shocks to help control abnormal heart rhythms,
especially ones that can be life-threatening. An ICD is also known as an
automatic implantable cardioverter-defibrillator (AICD).
An ICD is implanted under the skin in the chest. A wire threaded
through a large vein connects the device to the heart.
An ICD is always checking your heart rate and rhythm. If the ICD detects a life-threatening rapid heart rhythm, it tries to slow the rhythm to get it back to normal. If the dangerous rhythm does not stop, the ICD sends an electric shock to the heart to restore a normal rhythm. The device then goes back to its watchful mode. If your heart is beating too slowly, the ICD acts as a pacemaker, sending mild electrical pulses to bring your heart rate back up to normal.
Current as of:
February 20, 2015
E. Gregory Thompson, MD - Internal Medicine & Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2015 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.
You'll find Decision Points to help you answer questions about:
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.