Use of the Sentinel (Boston Scientific) embolic protection device is highly variable and its ability to limit cerebral injury modest at best, a TVT Registry study suggests.
The primary analysis, using an instrumental variable approach, showed no significant reduction in in-hospital or 30-day stroke with the device among more than 120,000 transcatheter aortic valve replacements (TAVRs) performed in the United States since its approval.
“Nevertheless, the secondary propensity-weighted analysis and the confidence interval for the primary analysis are consistent with a possible modest relative risk reduction in stroke of about 20% and a number-needed-to-treat of about 300 to prevent one stroke,” David J. Cohen, MD, University of Missouri Kansas City School of Medicine.
“These findings support clinical equipoise and provide a strong rationale for ongoing large-scale randomized trials to test whether embolic protection devices provide meaningful clinical benefit,” he said during a late-breaking trial session at TCT Connect, the virtual meeting of Transcatheter Cardiovascular Therapeutics (TCT) 2020.
Stroke continues to occur in 2% to 5% of patients undergoing TAVR, however, embolic protection devices (EPDs) have only been tested in small randomized trials using primary imaging endpoints, Cohen observed. “Thus, there remains considerable uncertainty regarding the clinical benefits associated with these devices.”
The study included 123,186 elective or urgent transfemoral TAVR procedures between January 2018 and December 2019 in the Society of Thoracic Surgeons/American College of Cardiology TVT Registry. Of these, 12,409 were performed with an EPD and 110,777 were not. Sites performing less than 20 TAVRs/year and emergent, alternative access, or concurrent mitral/TAVR procedures were excluded.
The proportion of hospitals using EPD rose steadily from 7% in the first quarter of 2018 to 28% in the fourth quarter of 2019. The proportion of patients receiving the device increased from 5% to 13% over the same period.
Usage varied widely, with 66% of hospitals never using an EPD over the study period and only 5% using it more than 50% of the time, Cohen observed. “By Q4 2019, this had increased to 8% but was still an extreme minority of hospitals in the United States.”
In the instrumental variable analysis, the adjusted rate of the primary endpoint of in-hospital stroke was in 1.39% in patients treated with EPD and 1.54% in those with no EPD (relative risk [RR], 0.90; 95% CI, 0.68 – 1.13; P = .41).
Rates were also similar for in-hospital death or stroke (2.4% vs 2.6%), major bleeding (4.0% vs 4.4%), device success (97% vs 97.2%), 30-day stroke (2.0% vs 2.1%), and 30-day mortality (1.9% vs 2.2%).
In the propensity-weighted analysis, which accounted for 30 demographic, clinical, and hospital-level characteristics, however, in-hospital stroke occurred in 1.30% of patients with EPD and 1.58% without (RR, 0.82; 95% CI, 0.69 – 0.97; P = .02).
Significant differences were also observed in in-hospital death or stroke (2.1% vs 2.5%) and 30-day stroke (1.9% vs 2.2%) as well as mortality (1.7% vs 2.2%).
Accounting for Patient/Site Differences
EPD was more likely to be used in patients with bicuspid valves (6.8%), and less