Uptake, Geographic Access, and Outcomes of Transcatheter Mitral Valve Repair in the United States

BACKGROUND: The dissemination of novel procedures should attempt to strike a balance between access and procedure quality. This study aimed to evaluate the temporal trends and geographic dispersion of mitral transcatheter edge-to-edge repair (M-TEER) sites and to examine the associations of site volume and site-to-population density with patient outcomes. METHODS: We used the Medicare administrative databases in the United States to identify sites performing M-TEER in patients aged 65 to 99 years from 2017 to 2020 and examined the annualized volume and site-to-population density (per million beneficiaries in each corresponding hospital referral region). A hierarchical Cox regression analysis accounting for site-level clustering was performed to assess the association of site volume and density with 30-day and 1-year all-cause mortality. RESULTS: We identified 456 sites performing M-TEER in 16 810 patients (median [interquartile range] age, 81 [75-86] years; female, 47%). The case number of M-TEER increased by 54% from 3125 in 2017 to 4820 in 2020, while sites performing M-TEER increased by 71% from 252 in 2017 to 432 in 2020, corresponding to a decline in the median patient-to-site distances from 37.1 kilometers (interquartile range, 14.4-105.0) to 28.6 kilometers (interquartile range, 12.8-74.9). Higher site volume (every 10 cases/y) was associated with lower 30-day (adjusted hazard ratio, 0.94 [95% CI, 0.91-0.99]) and 1 year (adjusted hazard ratio, 0.98 [95% CI, 0.96-1.00]) mortality, while there was insufficient evidence to determine the association between higher site density (every 1 site/million-beneficiaries) and 30-day (adjusted hazard ratio, 1.00 [95% CI, 0.99-1.02]) and 1-year (adjusted hazard ratio, 1.00 [95% CI, 0.99-1.01]) mortality. CONCLUSIONS: Although sites performing M-TEER have been rapidly expanding, we did not find associations between higher regional site density and patient mortality. Continuous careful planning in disseminating M-TEER while ensuring adequate procedure volume per site may optimize patient outcomes.