While the main PROTECTED TAVR trial found no significant differences in stroke rates when cerebral embolic protection (CEP) was used during TAVR compared with TAVR alone, a post hoc analysis of the trial presented during TCT 2024 and simultaneously published in JAMA Cardiology, suggests there may be potential benefits associated with CEP use based on geographic region.

The PROTECTED TAVR trial randomized 3,000 patients with asymptomatic aortic stenosis from 51 hospitals in the U.S., Europe and Australia to either TAVR with CEP (n=914) or TAVR alone (n=919). Overall results from the main trial found the incidence of stroke within 72 hours after TAVR or before discharge did not differ significantly between patients assigned to CEP compared with those undergoing TAVR alone and no interaction by geographic region was observed.

In the new exploratory post hoc analysis looking at those patients treated in the U.S. vs. outside the U.S., individuals in the U.S. CEP cohort exhibited a 50% relative risk reduction for overall stroke and a 73% relative risk reduction for disabling stroke compared to those treated with TAVR alone. No treatment effect on stroke risk reduction was observed in the cohort of patients from outside the U.S.

Researchers noted that of the 1,833 patients from the U.S., the majority were younger, more predominantly male, had a lower prevalence of atrial fibrillation, and had a higher prevalence of bicuspid aortic valve, diabetes, and peripheral vascular disease than those from Europe and Australia. These differences, along with procedural practices across regions, may have played a role in the results. ACC.org Editor-in-Chief Kim A. Eagle, MD, MACC, suggests a larger randomized study in U.S. sites may be worthwhile before any recommendations to use this strategy routinely are considered.

"While interpreting a post hoc analysis from a randomized clinical trial requires caution, our study provides important context to steer the ongoing debate about the clinical efficacy of CEP in addressing this serious complication," write Raj R. Makkar, MD, FACC, et al. "Analyses to identify variables that may be predictive of stroke or potential benefit with CEP are ongoing, potentially with individual patient data from other trials."