A Patent Foramen Ovale (PFO) closure is a common, minimally invasive procedure used to seal a small, flap-like opening in the wall separating the heart’s upper chambers. This intervention uses a catheter to deliver a specialized device that permanently closes the opening without the need for open-heart surgery. The procedure is typically performed to prevent serious neurological events in select patients.
Understanding the Patent Foramen Ovale
The PFO is a remnant of a structure present in every human heart before birth, known as the foramen ovale. This opening allows blood to bypass the lungs, which are not yet functional in the womb, by shunting blood from the right atrium to the left atrium. At birth, pressure in the left atrium rises as the lungs begin to work, pushing the flap closed, which typically seals permanently.
In approximately 25% of the general population, this flap does not fully fuse, resulting in a Patent Foramen Ovale. The PFO is an anatomical variant, not a structural defect, and in most people, it remains harmless and asymptomatic throughout life.
Medical Indications for Closure
The primary medical reason for recommending PFO closure is to prevent a recurrent stroke that has no other identifiable cause, known as a cryptogenic stroke. This occurs when a clot originating in the venous system travels to the right side of the heart. Instead of being filtered by the lungs, the clot passes through the PFO into the left side of the heart and travels to the brain, a process called paradoxical embolism.
Research shows that PFO closure combined with antiplatelet therapy is superior to antiplatelet therapy alone for secondary prevention of recurrent cryptogenic stroke, especially in younger patients. The decision for closure often weighs the risk of recurrence against the anatomical features of the PFO, such as a larger size or the presence of an associated atrial septal aneurysm.
PFO closure is also considered for specific high-risk scenarios, such as in professional divers who have experienced decompression sickness, often called “the bends.” The PFO can allow nitrogen bubbles to enter the arterial circulation, causing tissue damage. While not a standard indication, some patients with migraine headaches, particularly those with aura, may consider closure, though large randomized trials have yielded mixed results regarding efficacy.
The Catheter-Based Closure Procedure
The PFO closure is a percutaneous procedure, meaning the heart is accessed through the blood vessels rather than by opening the chest. The patient receives either conscious sedation or general anesthesia, and the procedure typically lasts between one and two hours.
The interventional cardiologist begins by making a small incision, usually in the groin area, to access the femoral vein. A catheter is then inserted and guided through the venous system up into the right atrium of the heart.
Imaging techniques, such as fluoroscopy (real-time X-ray) and echocardiography (ICE or TEE), are continuously used to visualize the heart’s anatomy and guide the catheter’s movement. This imaging is necessary for accurately measuring the PFO opening and selecting the appropriately sized closure device.
The closure device, often consisting of two wire-mesh discs made from a nickel-titanium alloy, is collapsed inside the delivery catheter. The cardiologist threads the catheter across the PFO from the right atrium into the left atrium. One disc is deployed on the left atrial side, and the catheter is pulled back until the second disc is deployed on the right atrial side, effectively sealing the opening. After confirming the device is securely positioned, the delivery catheter is removed, leaving the permanent implant in place.
Recovery and Follow-up Care
After the procedure, patients are monitored in the hospital for a short stay, typically 24 to 48 hours, with a period of bed rest to allow the access site in the groin to heal. Patients are advised to avoid heavy lifting or strenuous activity for a few days to a week to prevent complications at the puncture site.
A period of dual antiplatelet therapy (DAPT), usually a combination of aspirin and a second antiplatelet agent, is prescribed to prevent blood clots from forming on the newly implanted device. This dual therapy is recommended for three to six months while the body’s natural tissue grows over and incorporates the device.
Following the DAPT period, a single antiplatelet agent, most often aspirin, is typically continued for a longer duration, sometimes up to five years, as determined by the patient’s individual risk factors. The first follow-up appointment usually includes an echocardiogram at about six months to confirm that the PFO is fully sealed and that the device is stable and properly covered by tissue.