SANTA ROSA -- A team at Claret Medical, Inc., has developed what's designed to be a feasible and safe blood filtration technique to help reduce strokes following heart valve implantation.

The company is being recognized for its leadership in medical-device manufacturing.

In February, Claret Medical (claretmedical.com) announced that it had received investigative device exemption (IDE) approval for U.S. pivotal trial of The Sentinel cerebral protection system in the transcatheter aortic valve replacement (TAVR) patient population from the U.S. Food and Drug Administration (FDA).

The company now plans to initiate a 15-center human patient study in the U.S. over eight to 10 months, followed by a 510(k) FDA review cycle. Following final FDA approval, the device would be approved for use within the U.S. The approval process considers both the type of device and an analysis of clinical data from patients that have had the procedure.

[caption id="attachment_95447" align="alignleft" width="360"] Larry Carrier (left), vice president for regulatory and clinical quality; Tony Fields, chief operating officer; and Dan Fifer, vice president for research and development, in front of Claret Medical's clean room in north Santa Rosa.[/caption]

TAVR involves delivering a new heart value tightly packaged into a catheter and typically inserted through an artery in a patient’s leg and guided to the heart.

In a similar procedure, the two Sentinel filters are remotely deployed in arteries leading from the heart to the brain.

 “The Sentinel is designed to work with any cardiac intervention you can think of,” said Tony Fields, chief operating officer with Claret Medical. “While stroke is one of the most feared complications of cardiac interventions, other neuro cardiac cognitive impairing events, or deficits, can occur due to what is called silent infarct. Symptoms include short- and long-term memory loss, personality changes and a reduction in functional mobility, among others.”

He said there is big potential for Claret Medical, headed by President and CEO Azin Parhizgar, Ph.D., if their company can prove that its device can also reduce neurocognitive deficits.

[caption id="attachment_95448" align="alignright" width="315"] Claret Medical's The Sentinel filter is designed to collect debris from a transcatheter aortic heart valve replacement procedure before it can travel to the brain through the bloodstream and cause a stroke. These dual filters are placed in the carotid arteries branching from the aortic bridge leading away from the heart.[/caption]

With The Sentinel, small filters are temporarily placed inside the two carotid arteries leading to the brain from the aortic arch above the heart. These filters capture and remove debris (tissue fragments, calcium, etc.) released during TAVR, thus preventing them from traveling through the bloodstream to the brain where they can cause a stroke.

Without this next-generation dual filter-based solution, patients in need of a new heart valve have a one in 16 chance of stroke resulting from the TAVR procedure itself, because it does not utilize any form of cerebral vascular protection as a standard of care.

“Open heart surgery involves hospitalization, weeks of recovery time and often produces severe side effects,” Mr. Fields said. "Inserting a replacement valve through a patient’s artery is becoming widely accepted as a less-invasive alternative. Our procedure uses a similar transcatheter arterial delivery system to put Sentinel in place and remove it after sufficient time has passed to collect debris and mitigate the risk of stroke and neurocognitive deficit.

“We believe our device and techniques provide a more predictable and positive outcome for physicians and their patients.”

The Sentinel filters contain thousands of laser-drilled microholes in a polyurethane membrane with small hoops that deploy to expand the filters within each artery. The filter pore size is large enough to let blood flow through easily but small enough to collect particles that could cause a stroke -- 140-micron to 8-millimeter objects.

[caption id="attachment_95449" align="alignright" width="360"] The clean room and technicians at Claret Medical, maker of The Sentinel blood-filtration device designed to help reduce strokes after heart valve implantation.[/caption]

Traditional heart valve replacement surgery can take two to three hours or more. The TAVR procedure reduces that time to often less than an hour. It only takes minutes to insert the Sentinel filters.

On Jan. 27, Claret Medical announced that that it had received European CE Mark approval of its Sentinel Cerebral Protection System for reducing stroke during TAVR procedures. The company also has three ongoing clinical studies underway in Europe.

The Sentinel device is now commercially available in Europe, and is marketed through six distributors in 12 countries.

In addition to The Sentinel device, the company is looking farther down the road and thinking of other ways to protect the brain from stroke.

Stroke is the third leading cause of death. It kills 130,000 Americans among the more than 795,000 people in the U.S. that have a stroke each year, according to the Centers for Disease Control and Prevention.

On a global scale, 15 million people suffer strokes annually. Of these, 5 million die and as many are permanently disabled.   

In the U.S., about 87 percent of strokes are ischemic -- when blood flow to the brain is diminished by atherosclerosis (plaque deposits) as a result of aging, blocked due to thrombus (a blood clot) or when calcified material and tissue are liberated during transcatheter aortic valve replacement (TAVR) and other endovascular and surgical aortic valve interventions.

Founded in 2009 by former Medtronic AVE engineer Randy Lashinski with the help of a few prominent clinicians, Claret Medical is a cardiovascular medical device company developing novel cerebral vascular protection systems for TAVR, other endovascular procedures and surgical aortic valve replacement. The company received U.S. Patent No. 8,372,108 for its Intravascular Blood Filter on Feb. 12, 2013, and U.S. Patent No. 8,518,073 for its Illuminated Intravascular Blood Filter on Aug. 27, 2013.