Impact of Physician Experience on Stroke or Death Rates in Transfemoral Carotid Artery Stenting: Insights from the VQI

ObjectiveWith the recent expansion of the Centers for Medicare and Medicaid Services (CMS) coverage, transfemoral carotid artery stenting (tfCAS) is expected to play a larger role in the management of carotid disease. Existing research on the tfCAS learning curve, primarily conducted over a decade ago, may not adequately describe the current effect of physician experience on outcomes. This study evaluates the tfCAS learning curve using VQI data. MethodsWe analyzed tfCAS patient data from 2005-2023. Each physicians procedures were chronologically grouped into 12 categories, from procedure counts 1-25 to 351+. Primary outcome was in-hospital stroke/death rate; secondary outcomes were in-hospital stroke/death/MI, 30-day mortality, and in-hospital stroke/TIA. The relationship between outcomes and procedure counts was analyzed using Cochran Armitage test and a generalized linear model with restricted cubic splines, validated using generalized estimating equations. ResultsWe analyzed 43,147 procedures by 2,476 physicians. In symptomatic patients, there was a decrease in rates of in-hospital stroke/death (procedure counts 1-25 to 351+: 5.2% to 1.7%), in-hospital stroke/death/MI (5.8% to 1.7%), 30-day mortality (4.6% to 2.8%), in-hospital stroke/TIA (5.0% to 1.1%) (all p-values<0.05). The in-hospital stroke/death rate remained above 4% until 235 procedures. Similarly, in asymptomatic patients, there was a decrease in rates of in-hospital stroke/death (2.1% to 1.6%), in-hospital stroke/death/MI (2.6% to 1.6%), 30-day mortality (1.7% to 0.4%), and in-hospital stroke/TIA (2.8% to 1.6%) with increasing physician experience (all p-values<0.05). The in-hospital stroke/death rate remained above 2% until 13 procedures. ConclusionsIn-hospital stroke/death and 30-day mortality rates post-tfCAS decreased with increasing physician experience, showing a lengthy learning curve consistent with previous reports. Given that physicians early cases may not be included in the VQI, the learning curve was likely underestimated. With the recent CMS coverage expansion for tfCAS, a significant number of physicians would enter the early stage of the learning curve, potentially leading to increased post-operative complications. ARTICLE HIGHLIGHTSO_ST_ABSType of ResearchC_ST_ABSRetrospective analysis of prospectively collected Vascular Quality Initiative registry data. Key FindingsIn patients undergoing tfCAS in VQI, in-hospital stroke/death, in-hospital stroke/death/MI, 30-day mortality and in-hospital stroke/TIA decreased with increasing physician experience in both symptomatic and asymptomatic patients. In symptomatic patients, in-hospital stroke/death rate did not drop below 4% until after 235 procedures, and it remained above 2% until 13 procedures in asymptomatic patients. Take home MessageThis study showed a decrease in post-operative in-hospital stroke/death with a substantially high risk in an operators first 25 procedures in VQI. The recent expansion of the Center for Medicare and Medicare Services coverage of tfCAS warrants caution since a rise in early-phase physicians could lead to increased post-operative complication rates in transfemoral carotid artery stent patients. Table of Contents SummaryIn this retrospective analysis of the tfCAS learning curve, in-hospital stroke/death, in-hospital stroke/death/MI, 30-day mortality, and in-hospital stroke/TIA rates decreased significantly with increased physician experience. With the recent CMS coverage expansion for tfCAS, more physicians would enter the early stage of the learning curve, potentially leading to increased post-operative complications.