Penn Physicians Place Region’s First Subcutaneous ICD

In August, electrophysiologists from Penn Medicine implanted the region’s first subcutaneous implantable cardioverter defibrillator (ICD) for sudden cardiac arrest, a potentially fatal electrical malfunction of the heart. The patient, a young athletic male in his 20s, had the new system implanted during an outpatient procedure at the Hospital of the University of Pennsylvania (HUP).

“I am very glad we are able to provide this technologic breakthrough. He is an athletic young man who is now protected from life-threatening arrhythmias. It is reassuring to not have to worry about problems related to intravascular leads,” said Frank Marchlinski, MD, director of the Penn Medicine electrophysiology program.

Conventional ICDs require placement of at least one lead in or directly on the heart. Most frequently they are threaded through a vein and then placed inside the heart. The device then monitors the heart’s rhythm and delivers a life saving electric shock when a harmful arrhythmia is detected.

The new device, known as a subcutaneous implantable defibrillator or S-ICD, works much like an external defibrillator, but the entire system is implanted just under the skin on the chest. A small power unit is placed under the skin on the side of the chest and is attached to a thin sensor and shocking cable implanted under the skin near the breast bone. The new device implantation is part of an ongoing clinical trial that involves 35 sites globally. Penn’s patient is one of only 330 total patients enrolled in the trial around the world.

The trial is a prospective, multicenter, single-arm design approved in the U.S. by the FDA under an investigational device exemption (IDE). Results from four studies conducted at eight sites in Europe found that the S-ICD detected 100 percent of induced and spontaneous irregular heart rhythms with 98 percent conversion success. They confirmed that the subcutaneous defibrillator helped reduce problems associated with traditional models, including difficulty implanting the leads, risk of damage to the heart or the device, chance of infection and the need to remove a defective or damaged electrode in or on the heart. The device received European approval in 2009 and is commercially available there.