Longer Time Interval Between Carotid Cross-Clamping and Shunting Is Associated With Increased 30-Day Stroke and Death Rate

Abstract

Background: The benefit of carotid endarterectomy (CEA) in patients with a significant (>70%) (a)symptomatic stenosis has been proven thoroughly in major trials. It is unknown whether, after cross-clamping the carotid artery, the time interval between determination that a shunt is needed and the actual functioning of the shunt, defined as the need for shunt-to-shunt time (NST), influences 30-day morbidity and mortality rate after CEA. Methods: Experienced vascular surgeons performed 851 CEAs with a selective shunting protocol based on perioperative transcranial Doppler measurement and electroencephalographic findings, and data were analyzed retrospectively. The study included 156 shunted patients. Results: Longer NST was associated with an increase in the 30-day stroke/death rate. A binary logistic regression model was used to determine a 2-tailed P value of .004 and an odds ratio of 1.5/min increase of the NST. There was no influence on stroke-death rate of gender, age, symptomatic or asymptomatic stenosis, the use of a patch or not, or the number of periprocedural microembolic signals. Conclusion: If CEA is performed with a selective shunting protocol, a longer NST increases the 30-day stroke/death rate. These results support a strong recommendation that shunt placement should be as quick as possible.

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