A catheter used to treat malformed blood vessels has been linked to nine patient deaths.
The FDA issued a safety alert regarding the Onyx Liquid Embolic System, which is manufactured by Covidien unit, ev3. The safety alert notes that some catheters have broken or become entrapped in the body after treatment.
The system is usually used to treat patients diagnosed with brain arteriovenous malformations (brain AVMs), the FDA noted. AVM’s affect about 0.5 percent of people and can lead to aneurysm and stroke when left untreated.
The system is meant to reduce bleeding and surgical complications when the brain AVM is removed, which typically occurs a few days following Onyx treatment.
The device uses a spongy material to block off blood flow to abnormal tangles of blood vessels before they are removed by surgery. The material is delivered to the brain through a tube inserted into a groin artery, known as a catheter.
During the Onyx embolization procedure, the physician uses fluoroscopy to guide the catheter to the site where the Onyx material will be implanted. Onyx material is then injected through the catheter into the blood vessels of the brain at the location of the AVM, solidifying when the material comes in contact with blood so that blood flow to the brain AVM can be blocked.
But the catheter can get stuck in the spongy material while inside the brain, causing serious complications including hemorrhage and death, the U.S. Food and Drug Administration said in a Safety Communication notice.
Since the device was approved in 2005, the FDA said it has received more than 100 reports of the catheter breaking after it became stuck, including nine deaths. In at least 54 cases, the catheter could not be removed, leaving it implanted in the patient.
“Neither (the spongy material) nor the catheter is intended to be long-term implants, and patients may need additional medical interventions to have the catheter removed if it becomes entrapped,” the FDA said in the notice.
The FDA said it changed the label for the device in April to let doctors know about the risk of the catheter getting stuck in people’s brains.
Complications from catheter entrapment can be serious, the regulatory agency said, and include potential hemorrhage and death, as well as parts of the Onyx plug or catheter migrating to other parts of the body. Should catheter entrapment occur, the patient may need to take antithrombotic drugs to prevent blood clots around the catheter, and may need to undergo one or more imaging procedures to locate a piece of the catheter and Onyx plug, increasing patient exposure to radiation.
The potential for catheter entrapment only occurs during implantation, according to the agency’s alert. Patients treated with Onyx, but who suffered no complications at the time, are not at risk.
The agency now recommends that health care providers carefully select patients for the procedure and adhere to manufacturer instructions for removal of any entrapped catheter.