VIDEO: Exploring the use of cerebral protection devices during TAVR

Overall, the researchers in the late-breaking trial at the Transcatheter Cardiovascular Therapeutics (TCT) 2022 meeting found Boston Scientific’s Sentinel Cerebral Protection System was not associated with a significant reduction in the number of periprocedural strokes within 72 hours of TAVR, the primary endpoint. The secondary endpoint of disabling strokes was reduced by 60%. Kapadia was encouraged by that data point and concluded the Sentinel device should be considered positive and made available for all TAVR patients. 

He also noted that, overall, post-TAVR stroke rates have been decreasing as the technology improves and operators gain experience.

"The stroke rate is decreasing and the procedures are becoming safer, so you need thousands of patients to see a difference. It does not mean the difference does not exist," Kapadia explained. "That is why we wrote in the publication in the New England Journal of Medicine that this was not a negative study. This is a study that shows that there may be a difference, but we could not show the difference in the primary endpoint ... with the small number of patients, it is going to be difficult to prove this minor difference."

This is similar to the improved outcomes in stents, where the adverse event rates are now so low that it would now require massive studies of 40,000 or more patients to be sufficiently powered to show any significant safety differences between the top stents in the U.S. market. These types of large head-to-head studies are no longer done because it would be prohibitively expensive to run.

The PROTECT TAVR and other studies of the Sentinel device also did find embolic material captured in the filters in the majority of patients.

Cost vs. benefit of using embolic protection in TAVR

Kapadia said the use of embolic protection systems in TAVR to prevent a relatively small number of strokes has boiled down to costs versus benefits for the patient. Because the stroke rate is low in TAVR, lower than surgery today, this weighs in on decisions for using an ancillary filter device that adds cost to a procedure.

He said the cost of a TAVR valve is around $32,000 and the use of a cerebral protection filter adds about another $3,000.

"Business wise, for an ancillary device that does not cost that much, what is our threshold to say we accept the data or we don't accept the data?" he asked. "Do we run an even bigger randomized trial, or do we say we have enough data from different sources that are making sense to say this is enough evidence to use it and it will cost more and somehow pay for it? This is a difficult question."

Since the reimbursement for TAVR is a fixed amount payment, the cost of the embolic protection device lowers the amount a hospital can make performing these procedures. 

"We are using the hospital's money to purchase the device, so if the evidence does not exist to conclusively use it, no one is going to blame us for not using it. As a physician, the question for me is not about the blame, but what is the right thing to do," he said.

When Kapadia delivered the data at TCT, panelists debated if this was a positive trial or not. A key question raised was if they would want to have embolic protection if they or a loved one was undergoing TAVR, and the consensus was that they would.