Marketing Approved for Clot Retrieval Devices to Reduce Disability in Stroke Patients
The devices allow physicians to remove blood clots through a catheter or sheath
The Food and Drug Administration (FDA) is allowing the marketing of two medical devices that will allow doctors to remove blood clots from a patient's blood vessel following a stroke.
The Trevo clot removal devices may be marketed as an initial form of therapy for patients who have suffered strokes caused by blood clots. When used as a therapy, the patient may experience reductions in paralysis, difficulty speaking, and other disabilities caused by strokes.
Trevo is inserted by a doctor into a blood vessel through a catheter. Upon reaching the site of a blood clot, the shaped section at the end is fully expanded and takes hold of the clot. The doctor can then remove the clot by pulling the Trevo back through the vessel and remove it through a sheath or catheter.
Trevo devices should be used no later than six hours after the symptoms begin. Furthermore, it should only be used after the patient has received treatment no later than three hours after the symptoms appear by a drug that dissolves clots, such as a tissue plasminogen activator (t-PA).
"This is the first time FDA has allowed the use of these devices alongside t-PA, which has the potential to help further reduce the devastating disabilities associated with strokes compared to the use of t-PA alone," said Carlos Peña, Ph.D., director of the division of neurological and physical medicine devices at the FDA's Center for Devices and Radiological Health.
"Now health care providers and their patients have another tool for treating stroke and potentially preventing long-term disability."
The FDA first approved the devices in 2012 to remove blood clots and thereby restore the flow of blood in patients who had experienced strokes but who either could not receive a t-PA or who had no response to therapy by such a drug. This move by the agency to allow marketing will allow more patients to receive therapy with the devices.
Before approving marketing for Trevo devices, the FDA reviewed clinical trial data that compared 96 patients randomly selected to be treated with the Trevo in addition to t-PA therapy and medical management of blood pressure and disability symptoms to 249 patients who experienced only t-PA therapy and medical management. In this trial, 29 percent of the patients who were treated with the Trevo device were found to be functionally independent three months after experiencing the stroke, that is, they had either no symptoms or only a slight disability. Only 19 percent of the patients who were not treated with the Trevo device were functionally independent at that time.
There are some risks to using a Trevo device. These include a failure to remove the blood clot and a malfunction of the device, including device breakage and difficulty navigating within the blood vessels, which may cause damage to the vessels and lead to perforation or hemorrhage.