Predicting transient ischemic attack after carotid endarterectomy: The role of intraoperative neurophysiological monitoring

Abstract

ObjectiveTransient ischemic attacks (TIA) after carotid endarterectomy (CEA) are not well-studied. We aimed to investigate the characteristics and the predictive role of intraoperative neurophysiological monitoring (IONM) in TIA post-CEA. MethodsPatients who underwent CEA utilizing IONM from 2009-2020 were included. Analyses included TIA incidence, sensitivity, specificity, and predictive values of IONM, risk factor regression analyses, and mortality Kaplan Meier plots. ResultsOut of 2232 patients, 46 experienced TIA, 14 of which were within 24 hours of CEA (p < 0.01). Nine of these patients displayed significant IONM changes during CEA. The odds of TIA increased with somatosensory evoked potential (SSEP) changes (Odds Ratio (OR): 2.48 95% Confidence Interval (CI): 1.14–5.4), electroencephalogram (EEG) changes (OR: 2.65 95% CI: 1.22–5.77), and combined SSEP/EEG changes (OR: 2.98 95% CI: 1.17–7.55). Patients with TIA were less likely to be alive after an average of 4.3 years (OR: 0.5 95% CI: 0.26–0.96). ConclusionsThe odds a patient will have TIA post-CEA are greater in patients with IONM changes. This risk is inversely related to the time post-CEA. SignificanceChanges in IONM during CEA predict postoperative TIA. Post-CEA TIA may increase long-term mortality, thus further research is needed to better elucidate clinical implications of postoperative TIA.