Patent Foramen Ovale (PFO) is an opening in the heart between the right and left atrium that is present in all infants. It normally closes after birth, but a persistent hole in the septum exists in as many as one in four adults. The defect remains undetected in the majority of patients; few have any symptoms whatsoever. However, recent studies have shown that the risk of suffering an embolic stroke may be increased for approximately 25 percent of the population affected with this abnormality.
Until recently, the standard of care for PFO consisted of lifetime anticoagulants or open-heart surgery. Lakeland Heart Center interventional cardiologists Thomas Pow and Dilip Arora offer an alternative: a minimally invasive procedure that closes the hole permanently, eliminating the risk of stroke.
Diagnosis
"A PFO frequently
goes undiagnosed until the patient experiences a transient ischemic attack or a
stroke," comments Dr. Arora. "PFOs are frequently being seen as the cause of
paradoxical embolic events in otherwise healthy individuals. Recent studies
suggest that as many as 50 percent of cryptogenic strokes are related to PFO." A
transechocardiogram (TEE) is used to conclusively diagnose a PFO.
Congenital Defect
The
foramen ovale, used during fetal circulation to speed up the travel of blood
through the heart, usually closes within 10 days after birth due to increased
blood pressure in the left atria. However, should the foramen ovale remain
patent throughout the patient’s life, the incomplete closure of the septum
results in a flap or valve-like opening in the atrial septal wall. The condition
can lead to stroke when the pressure caused during a Valsalva maneuver can open
the defect, allowing blood to pass from the venous system to the arterial system
without first being filtered through the lungs. Debris in the blood can cross
over to the left atria, traveling to the brain and resulting in stroke.
Treatment
Surgical closure
of the PFO, while effective, is costly and invasive. Patients risk the major
complications of open surgery and must undergo a lengthy recovery period. PFO
patients can now benefit from a non-surgical procedure performed in the cardiac
cath lab, which successfully and permanently closes the defect.
"Transcatheter closure of a patent foramen ovale is currently the state-of-the-art strategy for the prevention of recurrent embolic stroke in this patient population," explains Dr. Pow. "The transcatheter procedure permanently seals the defect with very low risk and a short recovery period."
"The minimally invasive technique offers several advantages over traditional surgical methods or its alternative, a lifetime of anticoagulation therapies, with their potential side effects and inconveniences," commented Dr. Arora.
Percutaneous closure involves a catheter-delivered cardiac implant. Prior to the procedure, transesophageal echocardiography is used to obtain superior visualization of the interatrial septum, measure the hole and determine the size of the necessary implant. Through a small incision in the groin, the implant is introduced via the heart and across the patent foramen ovale. The device is then released through the delivery sheath, closing the foramen ovale. Tissue will eventually grow into and around the implant’s fabric and metal framework, creating a permanent seal.
Drs. Pow and Arora have performed 25 PFO closures since they began offering the service in 2003.
The procedure has a 100 percent success rate. No patients have suffered complications or recurrent strokes. In several, the closure effectively eliminated subsequent strokes.
For more information, a consult, or to refer a patient, call Great Lakes Heart and Vascular Institute at 269-985-1000.
