An implantable cardioverter defibrillator (ICD) is a medical device that monitors your heart and manages heart rate when needed. It’s surgically placed under your skin and connects to your heart with thin wires (leads). The battery-powered device can deliver an electric shock to correct life-threatening arrhythmia and prevent sudden cardiac arrest.
An implantable cardioverter defibrillator (ICD) is a medical device that’s surgically placed under the skin on your chest. It consists of a battery and thin wires called leads. The battery is about the size of a stopwatch and the leads go into your heart chambers to regulate your rhythm.
The battery-powered device constantly tracks heart rate and rhythm. Its pulse generator delivers an electric shock when needed to correct arrhythmia. The leads carry the shock to your heart.
ICDs are used to:
An ICD is different than a pacemaker. A pacemaker consistently maintains a normal heart rate. An ICD monitors your heart rate and intervenes only when necessary. However, some ICDs can function as pacemakers, too.
You may need an ICD if you have certain heart conditions that can’t be managed with other treatments. Conditions often treated with ICDs include:
A cardiac surgeon or an electrophysiologist implants an ICD.
ICD batteries last about seven years. Your healthcare provider should check them every three to six months.
Depending on the type of ICD you get, the device may be able to store data about your heart rhythm and keep a record. Your healthcare provider can then review that information remotely to make treatment decisions.
Some ICDs can provide a range of treatments as ordered by your doctor. For example, a doctor can remotely direct the ICD to deliver a mild to strong shock as needed.
Before you get an ICD, your healthcare provider may ask you to:
An ICD procedure is usually performed in a hospital or clinic. It takes a few hours.
The type of procedure you have depends on your health, the type of device and other surgical interventions you need at the same time.
The transvenous approach is the most common procedure. It requires a small incision near your collarbone. Your healthcare provider threads the leads through veins and accesses your heart. But sometimes implantation requires open-heart surgery.
ICD processes can vary widely. But in general, your healthcare provider will:
After ICD implantation, you may feel tired and sore, especially near the incision. Your healthcare provider may suggest pain medications to make you more comfortable.
Many people go home the day after surgery. Depending on your health and the type of procedure you had, you may have to stay in the hospital for a few days.
Just before you go home, your healthcare provider may test the ICD system again.
An ICD can be programmed to give low-energy or high-energy shocks. A low-energy shock can feel like a flutter or thump in your chest. High-energy shocks are for more severe conditions and can be painful for a moment, like a blow to the chest.
Most people need only one shock to restore normal heart rhythm, but some may receive two or more shocks in 24 hours. Your healthcare provider can adjust the frequency and intensity of shocks.
If you have three or more shocks in a short amount of time, seek immediate medical attention. That’s called an electrical storm or arrhythmia storm. It could mean you’re having a cardiac emergency or that the ICD isn’t functioning properly.
An ICD can prevent life-threatening arrhythmia and sudden cardiac arrest. It also can provide important information about your heart to your cardiologist.
ICD implantation is generally safe. But, as with any surgery, the procedure comes with risks, including:
If you have an ICD, carry a card in your purse or wallet to alert emergency personnel. This will help them make medical decisions if you have a medical emergency and are not able to tell them about the device.
Similarly, you should tell all your healthcare providers that you have an ICD. This includes dentists and imaging technicians, who may use equipment that can interfere with an ICD’s function.
Some technology can interfere with an ICD’s function. Ask your healthcare provider if you should use caution with:
After surgery for ICD implantation, tell your healthcare provider if you develop any signs of infection:
After ICD surgery, seek medical attention immediately if you receive several shocks in a short period of time.
A note from Cleveland Clinic
An implantable cardioverter defibrillator (ICD) is a medical device that constantly tracks your heart rate and rhythm, then delivers an electric shock if it detects an irregular heart rhythm. If you have an ICD, tell all your healthcare providers. And be aware of the things that can interfere with the device’s function.
Last reviewed by a Cleveland Clinic medical professional on 05/15/2022.
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