An implantable cardioverter defibrillator is a device used to regulate irregular heart rhythms by sending electrical pulses or shocks to the heart to help control life-threatening arrhythmias.

What is an implantable cardioverter defibrillator and why would I need one?

An implantable cardioverter defibrillator (ICD) device recognizes when the heart is beating dangerously fast. If your heart begins beating dangerously fast, the device will try to correct the rhythm by delivering rapid electrical signals to the heart which you will not be able to feel. If the rhythm does not respond to these signals the ICD will give a controlled electrical shock to correct the dangerous rhythm. You will feel this shock.

ICDs are usually very effective at being able to correct a dangerous rhythm and usually work within 10 seconds of detecting the problem. ICDs do not prevent the dangerous rhythm from happening so you will also need to continue taking medication.

An ICD may be suggested because you are having dangerous fast heart rhythms or are at risk of having dangerous fast heart rhythms. These life-threatening rhythms can be corrected by an ICD.

The ICD device has two parts:

  • The battery or generator
  • The pacing wires, called leads. There may be one or two leads.

There is always a high voltage lead, so if only one lead is implanted it can do both pace and provide a controlled electrical shock if needed. The generator monitors your heart beat and rhythm. When needed, it sends an impulse to your heart. The leads go from the device to the inside of your heart. They are attached to the heart muscle.

How long does an ICD device last?

The battery life of the device depends on the type of device. Usually, the battery lasts about six to 10 years. Most people have their battery checked every six to 12 months at a Cardiac Clinic or their heart specialist’s office. Your electrophysiologist may decide to use remote monitoring of your device. The leads can last many years and may never need to be replaced.

How can I prepare for my ICD implant?

Follow these preparation steps to prepare for your pacemaker procedure. Contact your doctor or the implantable cardiac electrical devices coordinator at 1-855-529-7223 if you have any questions prior to your procedure.

What is done during an ICD implant?

Learn more about how the pacemaker is inserted.


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