Heart device maker Boston Scientific Corp. has agreed to pay up to $270 million to acquire a California company called Claret Medical, which sells a temporary blood filter intended to prevent strokes by removing biological debris that can enter the bloodstream during medical procedures.

Boston Scientific, which employs thousands of Minnesotans in designing and making devices for the heart, announced Friday that it has offered to pay $220 million in upfront cash to buy Claret Medical, with another potential $50 million in payments down the road, based on reimbursement milestones. The deal is expected to close by the end of September.

Claret’s Sentinel Cerebral Embolic Protection System was cleared for U.S. sales last year by the U.S. Food and Drug Administration. Nearly 10,000 people worldwide have been treated with the device.

So far the main use of the device has been in combination with transcatheter aortic valve-replacement systems. TAVR devices are metal-and-tissue heart valves that can fold up into a tube that is inserted into a blood vessel and then unfurled over the diseased heart valve, allowing doctors to treat severely blocked or damaged aortic valves without open-chest surgery.

The minimally invasive procedure has allowed thousands of patients to get new heart valves who would have been considered high-risk or inoperable with traditional techniques. However, the technique can knock particles loose from the aortic arch and the valve leaflets, which can then travel to the brain and potentially block the flow of blood to brain cells. Recent studies estimate that about 4 percent of TAVR patients have a stroke within 30 days.

Claret’s Sentinel trial failed to show a statistically significant reduction in lesion volume in MRI scans at two to seven days post-procedure. However the trial did show that it was safe to add the Sentinel dual-filter device to a TAVR procedure, and debris was found in 99 percent of the filters used in the 240-patient study. Nearly 20 percent of the debris removed in the study recovered was more than 500 microns wide.

The Sentinel system is sold separately and will remain compatible with all TAVR systems on the market, not just those by Boston Scientific, a company spokeswoman said. Medtronic PLC and Edwards Lifesciences Corp. sell TAVR systems in the U.S. today, while Boston Scientific sells a TAVR system called the Acurate Neo in Europe.

Friday’s deal announcement said Boston Scientific has its eye on more than just TAVR procedures. The filter could also be used in transcatheter mitral valve replacements and closures of the left atrial appendage, as well as heart ablations for atrial fibrillation.