An experimental procedure that attempts to improve venous blood flow may cause significant damage or death in patients with multiple sclerosis, according to an alert issued by the Food and Drug Administration.
"Liberation therapy," which involves balloon angioplasty or stenting of veins in the neck and chest, has been used but not proven as a treatment for chronic cerebrospinal venous insufficiency (CCSVI), a condition characterized by stenosis of the veins draining blood from the brain and upper spinal cord. Despite the lack of a definitive link between CCSVI and multiple sclerosis (MS), the former has been suggested as a cause of or contributing factor in the development of the progressive, immune-mediated neurologic disorder (Ann. Neurol. 2010;67:286-90).
Since its introduction in 2009 (J. Vasc. Surg. 2009;50:1348-58), the liberation procedure has been linked to multiple complications, including stroke, stent detachment and migration, impairment of the treated vein, cranial nerve damage, blood clots, abdominal bleeding, and death, according to a statement issued by the FDA. The complications have been reported through the agency’s Safety Information and Adverse Event Reporting Program.
In the absence of rigorous, targeted research establishing an association between the two conditions or reliable evidence from controlled clinical trials demonstrating the efficacy of liberation-type procedures in MS, "patients are encouraged to discuss the potential risks and benefits of this procedure with a neurologist or other physician who is familiar with MS and CCSVI, including the CCSVI procedures and their outcomes," Dr. William Maisel, chief scientist in the FDA’s Center for Devices and Radiological Health, emphasized in the alert.
The statement also stresses that physicians and clinical investigators considering or conducting trials of devices to treat CCSVI are obligated to comply with regulations for investigational devices.
Currently, no devices for use in liberation therapy have received FDA approval for that indication, although doctors can and have offered the procedure to their patients, Dr. Maisel said in an interview. "We don’t know exactly how many individuals have had the treatment, because there is no central patient registry."