Operator Experience and Carotid Stenting Outcomes in Medicare Beneficiaries

CONTEXT: Although the efficacy of carotid stenting has been established in clinical trials, outcomes of the procedure based on operator experience are less certain in clinical practice. OBJECTIVE: To assess association between outcomes and 2 measures of operator experience: annual volume and experience at the time of the procedure among new operators who first performed carotid stenting after a national coverage decision by the Centers for Medicare P < .001) and among patients treated early (2.3%; 95% CI, 2.0%-2.7%) vs late (1.4%; 95% CI, 1.1%-1.9%; P < .001) during a new operator's experience. After multivariable adjustment, patients treated by very low-volume operators had a higher risk of 30-day mortality compared with patients treated by high-volume operators (adjusted odds ratio, 1.9; 95% CI, 1.4-2.7; P < .001). Similarly, we found a higher risk of 30-day mortality in patients treated early vs late during a new operator's experience (adjusted odds ratio, 1.7; 95% CI, 1.2-2.4; P = .001). CONCLUSION: Among older patients undergoing carotid stenting, lower annual operator volume and early experience are associated with increased 30-day mortality.