Regional differences in outcomes for patients undergoing transcatheter aortic valve replacement in New York state and Ontario

Background — TAVR has become the standard of care for a wide spectrum of patients with severe aortic stenosis. However, there are wide variations in access to TAVR between jurisdictions. It is unknown if such variation is associated with differences in post-procedural outcomes. Our objective was to determine whether differences in healthcare delivery in jurisdictions with high versus low access of care to TAVR translate to differences in post-procedural outcomes.

Methods — In this observational, retrospective cohort study, we identified all Ontario and New York State residents greater than 18 years of age who received TAVR from January 1st, 2012, to December 31st, 2018. Our primary outcomes were post-TAVR 30 day in-hospital mortality and all cause readmissions. Using indirect standardization, we calculated the observed versus expected outcomes for New York patients, had they been treated in Ontario.

Results — Our cohort consisted of 16,814 TAVR patients at 36 hospitals in New York State and 5,007 TAVR patients at 11 hospitals in Ontario. In Ontario, TAVR access rates increased from ∼18.2 TAVR/million in 2012 to 87.4 TAVR/million in 2018, while for New York State, the rates increased from 31.9 to 220.4 TAVR/million. For 30-day mortality, 3.1% of Ontario TAVR patients had an in-hospital death, compared to 2.5% of New York patients. With adjustment, this translated to an observed/expected ratio of 0.70 (95% CI 0.54-0.92) for New York patients.

Conclusions — Having greater access to TAVR maybe associated with improved outcomes, potentially due to an intervention earlier in the disease trajectory.