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Certain heart arrhythmias require treatment in the form of medical device implants. The Heart Hospital Baylor offers expertise in three implant devices available, which include a pacemaker, cardiac resynchronization therapy (CRT), and an implantable cardioverter defibrillator (ICD).

What is an ICD?

An implantable cardioverter defibrillator is a small device that's placed in the chest or abdomen. Doctors use the device to help treat irregular heartbeats called arrhythmias.

An ICD uses electrical pulses or shocks to help control life-threatening arrhythmias, especially those that can cause sudden cardiac arrest (SCA).

SCA is a condition in which the heart suddenly stops beating. If the heart stops beating, blood stops flowing to the brain and other vital organs. SCA usually causes death if it's not treated within minutes.

Who Needs an ICD?

ICDs are used to treat life-threatening ventricular arrhythmias, such as those that cause the ventricles to beat too fast or quiver. You may be considered at high risk for a ventricular arrhythmia if you:

  • Have had a ventricular arrhythmia before
  • Have had a heart attack that has damaged your heart's electrical system

Doctors often recommend ICDs for people who have survived sudden cardiac arrest (SCA). They also may recommend them for people who have certain heart conditions that put them at high risk for SCA.

How Does an ICD Work?

An ICD has wires with electrodes on the ends that connect to your heart chambers. The ICD will monitor your heart rhythm.​ If the device detects an irregular rhythm in your ventricles, it will use low-energy electrical pulses to restore a normal rhythm.

If the low-energy pulses don't restore your normal heart rhythm, the ICD will switch to high-energy pulses for defibrillation. The device also will switch to high-energy pulses if your ventricles start to quiver rather than contract strongly. The high-energy pulses last only a fraction of a second, but they can be painful.

Single-chamber ICDs have a wire that goes to either the right atrium or right ventricle. The wire senses electrical activity and corrects faulty electrical signaling within that chamber.

Dual-chamber ICDs have wires that go to both an atrium and a ventricle. These ICDs provide low-energy pulses to either or both chambers. Some dual-chamber ICDs have three wires. They go to an atrium and both ventricles.

The wires on an ICD connect to a small metal box implanted in your chest or abdomen. The box contains a battery, pulse generator, and small computer. When the computer detects irregular heartbeats, it triggers the ICD's pulse generator to send electrical pulses. Wires carry these pulses to the heart.

The ICD also can record the heart's electrical activity and heart rhythms. The recordings can help your doctor fine-tune the programming of your ICD so it works better to correct irregular heartbeats.

The type of ICD you get is based on your heart's pumping abilities, structural defects, and the type of irregular heartbeats you've had. Your ICD will be programmed to respond to the type of arrhythmia you're most likely to have.

ICD Surgery

Placing an implantable cardioverter defibrillator (ICD) requires minor surgery, which usually is done in a hospital. You'll be given medicine right before the surgery that will help you relax and might make you fall asleep.

Your doctor will give you medicine to numb the area where they will put the ICD. They also may give you antibiotics to prevent infections.

First, your doctor will thread the ICD wires through a vein to the correct place in your heart. An x-ray "movie" of the wires as they pass through your vein and into your heart will help your doctor place them.

Once the wires are in place, your doctor will make a small cut into the skin of your chest or abdomen. They will then slip the ICD's small metal box through the cut and just under your skin. The box contains the battery, pulse generator, and computer.

Once the ICD is in place, your doctor will test it. You'll be given medicine to help you sleep during this test so you don't feel any electrical pulses. Then your doctor will sew up the cut. The entire surgery takes a few hours.

Expect to stay in the hospital for one to two days after implantable cardioverter defibrillator (ICD) surgery. This allows your health care team to check your heartbeat and make sure your ICD is working well.

You'll need to arrange for a ride home from the hospital because you won't be able to drive for at least a week while you recover from the surgery.

For a few days to weeks after the surgery, you may have pain, swelling, or tenderness in the area where your ICD was placed. The pain usually is mild, and over-the-counter medicines can help relieve it. Talk to your doctor before taking any pain medicines.

Your doctor may ask you to avoid high-impact activities and heavy lifting for about a month after ICD surgery. Most people return to their normal activities within a few days of having the surgery.

Risks Related to ICDs

Unnecessary Electrical Pulses

Implantable cardioverter defibrillators (ICDs) can sometimes give electrical pulses or shocks that aren't needed.

A damaged wire or a very fast heart rate due to extreme physical activity may trigger unnecessary pulses. These pulses also can occur if you forget to take your medicines.

Children tend to be more physically active than adults. Thus, younger people who have ICDs are more likely to receive unnecessary pulses than older people.

Pulses sent too often or at the wrong time can damage the heart or trigger an irregular, sometimes dangerous heartbeat. They also can be painful and upsetting.

If needed, your doctor can reprogram your ICD or prescribe medicine so unnecessary pulses occur less often.

Risks Related to Surgery

Although rare, some ICD risks are related to the surgery used to place the device. These risks include:

  • Swelling, bruising, or infection at the area where the ICD was placed
  • Bleeding from the site where the ICD was placed
  • Blood vessel, heart, or nerve damage
  • A collapsed lung
  • A bad reaction to the medicine used to make you relax or sleep during the surgery

Other Risks

People who have ICDs may be at higher risk for heart failure. Heart failure is a condition in which your heart can't pump enough blood to meet your body's needs. It's not clear whether an ICD increases the risk of heart failure, or whether heart failure is just more common in people who need ICDs.

Although rare, an ICD may not work properly. This will prevent the device from correcting irregular heartbeats. If this happens, your doctor may be able to reprogram the device. If that doesn't work, your doctor might have to replace the ICD.

The longer you have an ICD, the more likely it is that you'll have some of the related risks.

Source: National Heart, Lung, and Blood Institute; National Institutes of Health; U.S. Department of Health and Human Services.

Why The Baylor Scott & White The Heart Hospital – Plano?​

The specialists on the medical staff of Baylor Scott & White The Heart Hospital – Plano lend their experience and many years of technical expertise to your care. Our multidisciplinary program draws from a broad spectrum of specialists including cardiac surgery, interventional cardiology, cardiology, vascular surgery, interventional radiology, and a team of dedicated cardiovascular nursing specialists. This multidisciplinary team works together to provide you with the most appropriate treatment approach to your unique heart or vascular condition.

For a physician referral, call 1.855.922.9567. Referring physicians may call 469.814.3565 to schedule a patient for evaluation.

Main phone number: 469.814.3278  469.814.3278 (HEART)

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