Implantable Defibrillators Save Lives

An implantable cardioverter defibrillator (ICD) is a small, pager-sized device that continually monitors the heart rate, ever ready to deliver a jolt of electricity.

“It is like having a built-in paramedic with me every place I go,” says Joe about his ICD. “Knowing it is there is a tremendous comfort. I know I do not have to worry about sudden death. I expect the machine to do the job.”

Joe, 69, has a long history of heart disease. He received an ICD after passing out due to an irregular heart rhythm.

Rachel received her first ICD after experiencing sudden cardiac arrest at age 33.

Most people with ICDs, like Rachel and Joe, have survived a cardiac arrest or suffer from irregular heart rates and have decreased heart function. However, people with other conditions, like a weakened heart muscle or hypertrophic cardiomyopathy may also be eligible for the devices.

What Does an ICD Do?

An ICD monitors the heart rate. If it detects a dangerous rhythm, it sends a shock of electricity to return the heartbeat to a normal pattern. Most units can also function as pacemakers. Some include special features to strengthen the heartbeat.

An ICD is placed under the skin near the collarbone. Wires from the device are attached to the heart during the short procedure.

Patients typically resume their normal activities after the procedure. They must make some changes, though, like avoiding MRI scans, heat therapy (used in physical therapy), high-voltage or radar machinery, or contact with radio or TV transmitters. Carrying a cell phone close to the ICD also should be avoided.

“An ICD needs careful consideration,” says Lisa, 34. She has hypertrophic cardiomyopathy, a genetic condition that increases her risk of sudden cardiac death. She received an ICD 5 years ago and trusts it more than her own heart. “It is going to be part of your life from here on out. Make sure all your questions are answered before the implant.”

Adjusting to the Technology

It takes most people time to psychologically adjust to the device. Anxiety is common. “The first couple of months I was very aware,” says Lisa. Her device has not gone off.

“I do not do anything that is going to get my heart rate way up there where I am going to test the boundaries of the device,” she says. “But I have a normal life and do not let it get in the way.”

Lisa is not alone in her concern. There is increasing evidence that patients who had an ICD placed experience symptoms of anxiety. Patients worry about increasing their heart rate and activities that could test the limits of the device.

Joe’s ICD has jolted his heart twice. After the first shock, while walking up a steep grade, his doctor adjusted the device’s parameters. A second shock occurred 4 years later.

“It felt like the kick of a mule in my chest,” Joe says. “I do not limit my activities at all. It might go off. I have had 2 experiences. But it is an instantaneous thing, and it goes away. I am fine afterward.”

Joe has walked 5-6 miles during a relay race. He scuba dives, walks 4 miles daily, exercises with weights, and does push-ups and sit-ups. “Before scuba diving, I called Medtronic (the manufacturer) to find out whether my ICD was capable of taking depths,” Joe says. He also contacted the company before traveling abroad to obtain a list of the medical facilities familiar with ICDs.

Rachel has not been so lucky. She has felt the kick 57 times. She exercises regularly and at first blamed that activity for triggering the ICD to deliver its jolt. However, then shocks occurred while watching television, in a restaurant, and during a speaking engagement.

“It got to the point I was afraid to go out of the house,” Rachel says. “I had to push through that by connecting with other people, going to support groups. Taking a step at a time, you do it.”

Rachel has worked through her anger, anxiety, and depression. She described it as a grieving process for her former self. Some people seek help with emotional aspects from a mental health counselor. Even with the multiple shocks, Rachel knows her ICD has saved her life and has no regrets.

“Without this defibrillator, I would not be where I am today,” she concludes. “It has given me some of the best years of my life.”

If you, or someone you know, is considering an ICD, contact a healthcare provider to determine if an ICD is right for you. Be prepared to discuss the physical and psychological adjustments of the device.


American Heart Association
Heart Rhythm Society


Heart & Stroke Foundation


Bostwick JM, Sola CL. An updated review of implantable cardioverter/defibrillators, induced anxiety, and quality of life. Psychiatr Clin North Am. 2007;30(4):677-688.
Goldberger Z, Lampert R. Implantable cardioverter-defibrillators: expanding indications and technologies. JAMA. 2006;295(7):809-818.
Implantable cardioverter defibrillator (ICD). EBSCO DynaMed website. Available at:
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Updated May 29, 2016. Accessed June 23, 2016.
Living with your implantable cardioverter defibrillator (ICD). American Heart Association website. Available at:
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Updated November 18, 2014. Accessed June 23, 2016.
Last reviewed June 2016 by Michael Woods, MD
Last Updated: 6/23/2016

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