The Relationship Between Hospital Stroke Center Designation and TVT Reported Stroke: The Michigan TAVR Experience

The 30-day rate of stroke after transcatheter aortic valve replacement (TAVR) has been suggested as a hospital quality metric. Thirty-day stroke rates for nonsurgical, high, and moderate-risk TAVR trials were 3.4% to 6.1%, whereas those in the national Transcatheter Valve Therapy (TVT) Registry for the same patient population were much lower. Hospital comprehensive stroke center (CSC) is the highest designation for integrated acute stroke recognition, management, and care.

Using Michigan TVT data, we assessed whether in-hospital post-TAVR stroke rates varied between CSC and non-CSC institutions.

TVT data submitted from the 22 Michigan Transcatheter Aortic Valve Replacement Collaborative participating institutions between January 1, 2016, and June 30, 2019, were included (N = 6,231). Bayesian hierarchical regression models accounting for patient clinical characteristics and hospital clustering were fitted to assess the association between hospital CSC accreditation and in-hospital post-TAVR stroke. Adjusted ORs and 95% credible intervals were estimated. The University of Michigan Institutional Review Board has waived the need for the approval of studies based on the data collected by the Blue Cross Blue Shield of Michigan Cardiovascular Consortium registry.

There were 3,882 (62.3%) patients at 9 CSC sites and 2,349 (37.7%) patients at 13 non-CSC sites. CSC sites had significantly higher rates of in-hospital post-TAVR stroke (CSC: 2.65% vs non-CSC: 1.15%; P < 0.001). After adjustment, patients who underwent TAVR at a CSC hospital had a significantly higher risk of in-hospital stroke (adjusted OR: 2.21; 95% CI: 1.03-4.62). However, CSC designation was not significantly associated with other important post-TAVR clinical outcomes including 30-day mortality.

Reported Michigan Transcatheter Aortic Valve Replacement Collaborative TVT stroke rates were significantly higher at sites with Joint Hospital Commission stroke designation status; however, other reported important clinical outcomes did not differ significantly based on this designation. CSC designation is a possible factor in stroke rate detection differences between TAVR institutions and might be a factor in the observed differences in stroke rates between TAVR trials and those reported in TVT. In addition, these data suggest that comparison between hospitals based on post-TAVR stroke rates is potentially problematic.