An implantable cardiac defibrillator (ICD) is a small, battery-powered device that can detect when a patient’s heart is beating dangerously fast and deliver a life-saving electrical shock to return the too rapid heart rate to a normal rhythm.
ICD devices are the size of a business card and are implanted under the skin just below the collarbone. Like pacemakers, ICDs contain a pulse generator which has a computer, battery and lead wires. The leads are in contact with the heart muscle on one end, while the other end is connected to the pulse generator.
ICDs are pre-programmed to send electrical signals to the heart. ICDs also can “communicate” with a special device which provides information about the patient’s heart rhythms and the overall condition of the ICD device. As with pacemakers, routine monitoring and follow-up care are necessary with an ICD to ensure the device continues to function properly.
Today, all ICDs also act as pacemakers and can prevent too slow heart rhythms by delivering pacing signals to the heart muscle. While pacing signals from the ICD are not felt by the patient, the life-saving shock signal delivered by an ICD is noticeable and has been described by patients as a “kick in the chest.”
A new technology, called a subcutaneous implantable cardiac defibrillator (S-ICD), provides life-saving intervention to patients without touching the patient’s heart. Unlike a regular ICD, there are no wires attached to the heart and the technique used to implant the device is also less invasive.
The device has obvious benefits for patients, including: increased lifestyle flexibility and a less complex surgery requiring a smaller incision to implant it.
The device is ideal for patients who are young and active, have congenital heart conditions or who are at risk for dislodging the wires of a traditional implantable defibrillator.
The S-ICD pulse generator is smaller than a roll of tape and is implanted under the skin and outside the rib cage at the patient’s left side. A small electrode is also implanted beneath the skin in the patient’s chest, running from the S-ICD to the center of the patient’s chest and up about five inches. No wires are threaded into the heart, and the device, being just under the skin, does not touch the heart muscle. The S-ICD also eliminates the need for follow-up surgery to replace or repair wires leading to the heart.
If the patient’s heart were to stop or experience a dangerous rhythm, the device would deliver an electrical signal to the heart with the goal of restoring the patient’s heart to normal rhythm and saving his/her life.
Summa Health System physicians implanted the first S-ICD in Ohio used outside of a clinical trial.
The new S-ICD manufactured by Boston Scientific gained FDA approval in 2012.