New device for fixing holes in hearts of young stroke patients

Mar 14 2006

As many as one in four adults is walking around with a "hole" between the upper chambers of the heart. Most of them will never know it.

The person who learns about the "hole" in his or her heart does so when he or she suffers symptoms of a mini-stroke (TIA) or a more-debilitating stroke. And it is usually only then that the person learns the term Patent Foramen Ovale (PFO), a persistent opening in the upper wall of the heart which did not close completely after birth.

"We are all born with a PFO," says Michael Savage, M.D. director, Cardiac Catheterization Laboratory at Thomas Jefferson University Hospital, Philadelphia. "For most of us, the opening closes within months after birth."

The symptoms occur--often in young adults--because the opening can cause the blood in the heart to be rerouted from the right to left side. As a result, if a clot forms in this rerouted blood and passes through the PFO to the brain, a person may experience a stroke or mini-stroke (TIA).

Interventional cardiologists have been using transcatheter devices designed to close PFO successfully for many years. Now in a multicenter study to be presented at the American College of Cardiology's 55th Scientific Session (Monday, March 13 at 10 a.m.), researchers from Thomas Jefferson University Hospital assess the initial U.S. experience with the Cardia PFO closure device for the prevention of recurrent stroke in patients with PFO. The Jefferson scientists will report that the Cardia PFO closure device is effective in sealing PFO and appears highly effective in preventing recurrent stroke.

The device, delivered through a catheter, is a tiny self-expanding double umbrella design consisting of polyvinyl alcohol sails and nitinol arms. It is positioned on both sides of the PFO and closes like a clamshell around the hole.

After several months, cells grow over and cover the device and it becomes part of the patient's body. "The patient is unaware that this is happening," says David Fischman, M.D., assistant director, Cardiac Catheterization Laboratory at Thomas Jefferson University Hospital.

Thomas Jefferson University Hospital was the lead center for the 22-site study. The goal was to determine implantation success for the device, procedural complications and recurrent stroke or embolization.

Ninety patients who had experienced a stroke--40 men and 50 women with an average age of 47 years--were treated and received the Cardia closure device. PFO closure was successful in 89 patients. Each was then prescribed daily doses of 325 mg. aspirin and 75 mg. clopidogrel (Plavix) for six months after the procedure.

"Followup with these patients was favorable in comparison with our prior experiences using blood thinners alone," said Dr. Savage, who is also associate professor of Medicine, Jefferson Medical College of Thomas Jefferson University. Of the group, one patient had a stroke, two died from non-device related causes and two patients experienced transient ischemic attacks (TIA).

In conclusion, the study authors found:

• The Cardia PFO closure device is effective in sealing PFO, with a high success rate observed even during this initial multicenter learning curve experience.
• The device appears highly effective in preventing recurrent stroke.
• These promising results underscore the importance of the pivotal randomized trial of this device in patients with strokes of unknown origin (cryptogenic).