Less than a week after the FDA awarded a fast-tracked approval for a new device to remove blood clots causing acute ischemic strokes, Stanford Hospital & Clinics became the first hospital in Northern California to have it available for use. 

The Solitaire FR represents a dramatic change from the corkscrew-shaped devices that have been the standard of care for the last decade. A randomized clinical trial of 113 patients at 18 U.S. hospitals comparing the Solitaire's effectiveness to the current designs ended early because of the significant improvement in results with the new device. At more than double the rate, the Solitaire cleared the blocked blood vessels. 

"We're obviously excited," said, Michael Marks, MD, chief of interventional neuroradiology at Stanford Hospital." There may still be instances where we use one of the current devices, but we're optimistic that we'll be using this device in the vast majority of cases and that we'll be successful in clearing clots at a much higher rate."

The new device is shaped like a stent, a mesh-like tube. It is inserted into a vessel, opened up and, after a short period of time, pulled out of the vessel. "The usual effect is that it will draw out the clot inside the stent or on the surface of the stent," Marks said. "The removal is often done simultaneously with a suction device and a balloon catheter."

The study's results also showed that the Solitaire patients had less bleeding in the brain, that it improved motor function at 90 days and that it opened more blood vessels when used as the first treatment approach. It restored blood flow to the brain 68 percent of the time, compared to 30 percent with the current device.

The need for changes in clot-removal devices is demanded by the nature of clots, Marks said. Depending on where they originate, anywhere from the heart to arteries in the neck, clots take on a particular composition and texture. The anatomy of the blood vessel where the clots are lodged can also influence how easily the clot can be removed. The corkscrew-shaped device has been in use for about a decade. The Solitaire has been in use in Europe since late 2009. Stanford was one of the hospitals where the Solitaire was tested in the randomized trial. In October, it was also the first hospital in Northern California qualified to offer the Pipeline stent, another FDA fast-track approved device for the treatment of brain aneurysms too large and wide to be treated reliably with conventional approaches. It, too, features a distinctive design.

By Sara Wykes