Implantable Cardiac Defibrillator

What is it?

An ICD is a battery-powered device placed under the skin (below your collarbone). It monitors your heart rate and sends electrical pulses to correct arrhythmias (dangerously rapid and chaotic heartbeats). This process is called defibrillation.

Thin wires called “leads” connect the ICD to one or more chambers in your heart. The leads allow the ICD to read the electrical activity in your heart. If the ICD detects an arrhythmia, it can deliver an electric pulse or a shock to help restore a normal heartbeat.

Frequently Asked Questions

Several heart conditions can increase your risk of develop life-threatening arrhythmias. For adults, the most common of these conditions is coronary artery disease. CAD can weaken and narrow your arteries, making it difficult for your heart to pump enough blood to the rest of your body.

Your doctor will conduct a comprehensive evaluation that includes your history, a physical examination, and electrocardiography (a graph that measures the  heart’s electrical impulses). You may also require a nuclear stress test, cardiac catheterization, and/or a cardiac MRI.

The ICD continuously monitors your heart rhythm. It is programmed to deliver small “pacing impulses” to restore a natural rhythm. If pacing is unsuccessful, it will deliver a stronger shock to the heart.

The device is implanted below the collarbone, usually on the left side. The leads are inserted into a vein and threaded into the heart.

It’s slightly smaller and thinner than a deck of cards.

It depends on the person and on the type of implant that you receive. Some implants are very small and some are a little bigger. If you’re thin, it generally will protrude more. If you have a little more bulk it will be less obvious. The device can be implanted under the breast muscle, which would prevent it from being seen. Speak to your doctor about options for your implant location.

Some people say it feels like being hit in the back with a baseball bat. Others says it feels like being kicked by a horse. It differs with everyone and only lasts for a second. Most people feel it more in the back than in the front.

Sit down. It’s possible that you could pass out from the shock, and don’t want to fall and/or hit your head. Call your doctor’s office and let them know you received a shock.

If you receive multiple shocks, go straight to the emergency room.

In either case, interrogation—which uses a device connected to your phone to monitor your device—will let your doctor know what happened.

No. Your life will only change if you allow it to. The ICD won’t hinder you or your activities that you do.

That depends on what you do for a living. Most people with an ICD are able to continue to work. Talk to to your doctor and discuss your occupation.

Every person is different. If you pass out from a shock, you may not be allowed to drive for six months. The rules vary from state to state. Talk to your doctor or call your local DMV.

Risks are rare (1%but they include bleeding, infection, swelling, blood leaking through the heart valve when the lead is placed, collapsed lung, blood clot, and stroke. ICD malfunctions are also rare (1%); if this happens, the device may either be reprogrammed or replaced.

No. Even if someone touches you when you are shocked it won’t hurt them. They may feel a tingle, like getting a static electricity shock from the rug.

Absolutely. In the beginning, many people worry about the shock, wondering if and when it will happen. Some people don’t even know they’re in arrhythmia when the device fires. However, other people have had an ICD for years and never experienced a shock. Joining a support group and meeting others who share your fears can help you feel better. If you continue to feel anxiety, please discuss the situation with your physician for additional treatment options.

  • Get your recommended device follow-up—generally two clinic visits per year, plus interim at-home monitoring. With regular device follow-up we can identify potential issues and correct them before you experience any negative effects.
  • Follow all doctors’ orders for prescribed medications, diet, fluid restrictions, and individual activity restrictions.
  • If you’re scheduled for an in-hospital procedure such as surgery, tell your cardiologist. The ICD will have to be disabled during surgery. MRIs are generally not recommended but they can be performed in certain situations. Be sure to tell your doctor you have an ICD.

Electromagnetic frequencies can interfere with the ICD’s ability to sense an abnormal rhythm. Generally, you just need to maintain a certain distance to avoid interaction.

These devices are safe to use:

  • Microwave ovens
  • Computers
  • DVR players
  • Small electrical tools
  • Garage door openers

Use caution around these devices:

  • Anti-theft security systems: These are unlikely to create any interference as you walk through them, but you should be aware of their locations.
  • Cell phones, Bluetooth headphones, and MP3 players (iPods): Keep these at least 6 inches away from your pacemaker. Hold the phone on the ear opposite your pacemaker.
  • Airport security scanners: When traveling in an airport, tell security you have a pacemaker and request a hand search.
  • Medical devices and procedures: Inform your dentist and other health care providers that you have a pacemaker before they perform any tests or procedures. Normal teeth cleanings are safe and require no special instructions.

Avoid these devices:

  • Large generators
  • Electrical transformers
  • Large machinery

It’s important to have an action plan in case there are changes in your condition. You should have your physician’s contact information for both regular business hours and emergencies. Learn what to do if you get a shock (or multiple shocks) from your device, or if you experience new symptoms, such as lightheadedness or syncope (fainting). Ask your doctor to discuss your emergency plans with you.