Regional variation in use and outcomes of combined carotid endarterectomy and coronary artery bypass

Abstract

ObjectiveIn treating concomitant carotid and coronary disease, some recommend staged carotid endarterectomy (CEA) and coronary artery bypass grafting, whereas others favor the combined approach (CCAB). Pressure to reduce surgical variation and to improve quality is real, yet little is known about how geographic practice differences affect outcomes. Using the Vascular Quality Initiative (VQI), this study evaluated regional variation in use and outcomes of CCAB. MethodsAll CCAB procedures in the VQI from 2003 to 2017 were reviewed and stratified into four regions, as defined by the United States Census Bureau. Primary outcomes included perioperative stroke, death, myocardial infarction (MI), and these as composite (SDM). A χ2 analysis was performed. ResultsThere were 1495 CCAB procedures identified, representing 1.8% of the VQI CEAs. Regions included the following: Midwest (MW), 32%; Northeast (NE), 39%; South (S), 25%; and West (W), 4%. Most were male (70%) and white (92%). There was significant regional variation in proportional volume of CCABs to all CEAs (0.7% [W] to 2.5% [MW]; P < .001). Regional variation in patch use (78% [W] to 93% [MW]; P < .001), shunting (29% [W] to 71% [MW]; P < .001), and electroencephalography monitoring (13% [W] to 52% [NE]; P < .001) was also significant. Overall perioperative stroke was 3.6%; death, 3.0%; and SDM, 6.8%. No regional difference was seen in outcomes of mortality (1.5% [MW] to 4.2% [NE]; P = .05), stroke (2.8% [NE] to 4.4% [MW]; P = .52), and MI (0.6% [MW] to 1.8% [W]; P = .62). When the Bonferroni correction was used, there remained no difference in stroke, MI, or SDM across regions, but mortality became significant. Using the Society for Vascular Surgery guidelines for consideration of CCAB, the minority of patients fell within the symptomatic carotid stenosis (SYMP, 15%; n = 218) or severe (≥70%) asymptomatic bilateral carotid disease (BIL, 18%; n = 267) categories. The most common indication was asymptomatic unilateral severe carotid stenosis (UNI, 37%; n = 552). There were no differences in regional outcomes stratified by indication (SYMP, BIL, UNI). Overall, when SYMP and BIL were compared with UNI, UNI had lower rates of stroke (2.4% vs 4.9%; P = .03) but similar MI (0.7% vs 1.2%; P = .40) and mortality (2.2% vs 2.5%; P = .75). ConclusionsSignificant variation exists across VQI centers in the use of CCAB. Despite differences in volume and practices, regional perioperative outcomes are similar. UNI is the most commonly used indication and has lower stroke rates relative to SYMP and BIL. CCAB is performed well across the United States, but most patients fall outside of Society for Vascular Surgery guidelines.