Intravascular procedures involving the carotid artery can be very dangerous because any disrupted plaque will quickly travel up the vessel, potentially resulting in an embolism in the brain. Silk Road Medical of Sunnyvale, California won FDA clearance to introduce its ENROUTE Transcarotid Neuroprotection System that prevents embolisms by reversing the blood flow in the carotid artery during angioplasty and stenting procedures. Temporary blood flow reversal of the carotid artery has been shown to be safe since collateral vessels via the Circle of Willis can compensate in the brain while a procedure is performed.
The technique relies on delivering a sheath into the carotid artery that is hooked up to an external device that forces the blood to reverse direction. As blood moves through the external controller, a filter removes bits of loose plaque before returning the blood back to the patient’s body. During this time the actual interventional procedure is performed and once complete the Silk Road device is disconnected and blood flow returns to its normal path.
Some details from Silk Road’s announcement:
The FDA cleared the ENROUTE Transcarotid NPS based in part on the results of the ROADSTER trial, which achieved a 30 day stroke rate of 1.4% in the pivotal cohort, the lowest to date for any prospective trial of CAS. There were no major strokes and there were no strokes in important high risk subgroups, including the elderly (age ≥75), women, and symptomatic patients.
Silk Road Medical has also submitted a Premarket Approval (PMA) application for the ENROUTE Transcarotid Stent System (Stent), which is an optimized stent delivery system designed for use with the ENROUTE Transcarotid NPS.
Here’s an animation describing the Silk Road procedure: