The FDA has approved the Amplatzer PFO Occluder device (St. Jude Medical, Inc.) to reduce the risk of a stroke in patients who previously experienced a stroke believed to be caused by a blood clot that passed through a small hole in the heart––called a patent foramen ovale (PFO)––and then traveled to the brain.
“The Amplatzer PFO Occluder provides a nonsurgical method for doctors to close a PFO,” said Bram Zuckerman, MD, director of the Division of Cardiovascular Devices in the FDA’s Center for Devices and Radiological Health. “But as the device labeling clearly states, patients need to be evaluated carefully by a neurologist and cardiologist to rule out other known causes of stroke and to help ensure that PFO closure with the device is likely to assist in reducing the risk of a recurrent stroke.”
Approximately 25% to 30% of Americans have a PFO, which typically causes no health problems and does not require treatment. The cause of most strokes can be identified, such as poorly controlled hypertension, atherosclerosis, or a blood clot caused by atrial fibrillation. However, in some patients, medical tests cannot identify the cause of the stroke, which is then referred to as a cryptogenic stroke. In a small percentage of these patients, it is believed that the PFO provided a path for a blood clot to travel to the brain, where it blocked a blood vessel and caused a stroke. Patients with a cryptogenic stroke and a PFO may be at an increased risk of experiencing a second stroke.
The Amplatzer PFO Occluder is inserted through a catheter that is placed in a leg vein and advanced to the heart. It is then implanted close to the hole in the heart between the right atrium and the left atrium. The device had been on the market more than a decade ago under a humanitarian device exemption (HDE), but it was voluntarily withdrawn by the manufacturer in 2006 after the FDA concluded that the target population for the device was greater than 4,000 patients and that the device no longer qualified for HDE approval. For the past 10 years, no marketed heart-occluder devices have been specifically indicated to close PFOs to reduce the risk of a recurrent stroke in patients with a prior cryptogenic stroke.
In approving the Amplatzer PFO Occluder, the FDA concluded that the device demonstrated a reasonable assurance of safety and efficacy. The device was assessed in a randomized study that evaluated 499 participants 18 to 60 years of age who were treated with the Amplatzer PFO Occluder plus blood-thinning medications compared with 481 participants who were treated with blood-thinning medications alone. While the rate of new strokes in both treatment groups was low, the study found a 50% reduction in the rate of new strokes in participants using the Amplatzer PFO Occluder plus blood-thinning medications compared with participants receiving only blood-thinning medications.
Adverse effects associated with the device or the implantation procedure include injury to the heart; atrial fibrillation; blood clots in the heart, leg, or lung; bleeding; and stroke.
The Amplatzer PFO Occluder device should not be used in patients with a heart-valve infection or other untreated infections, or with a heart tumor or blood clot at the implant site. The device is also contraindicated in patients with other abnormal connections between the heart chambers or in whom the cardiovascular anatomy or blood clots would interfere with the ability to move the catheter used to deliver the device to the heart.
Source: FDA; October 28, 2016.