Profiling Hospital Performance Based on Mortality After Transcatheter Aortic Valve Replacement in Ontario, Canada

Abstract

Background: Public reporting of hospital-level outcomes is increasingly common as a means to target quality improvement strategies to ensure the delivery of optimal care. Despite the rapid dissemination of transcatheter aortic valve replacement (TAVR), there is a paucity of reliable case-mix adjustment models for hospital profiling in TAVR. Our objective was to develop and evaluate different models for calculating risk-standardized all-cause mortality rates (RSMRs) post-TAVR.

Methods and results: In this population-based study in Ontario, Canada, we identified all patients who underwent a TAVR procedure between April 1, 2012, and March 31, 2016. For each hospital, we calculated 30-day and 1-year RSMR, using 2-level hierarchical logistic regression models that accounted for patient-specific demographic and clinical characteristics, as well as the clustering of patients within the same hospital using a hospital-specific random effects. We classified each hospital into one of 3 groups: performing worse than expected, better than expected, or performing as expected, based on whether the 95% CI of the RSMR was above, below, or included the provincial average mortality rate, respectively. Our cohort consisted of 2129 TAVR procedures performed at 10 hospitals. The observed mortality was 7.0% at 30 days and 16.4% at 1 year, with a range of 4% to 10% and 8% to 22%, respectively, across hospitals. We developed case-mix adjustment models using 28 clinically relevant variables. Using 30-day and 1-year RSMR to profile each hospital, we found that all hospitals performed as expected, with 95% CI that included the provincial average.

Conclusions: We found no significant interhospital variation in RSMR among hospitals, suggesting that quality improvement efforts should be directed at aspects other than the variation in observed mortality.

Keywords: mortality rate; reportings, hospital risk; statistical model; transcatheter aortic valve replacement.