Determinants of Pre- and Post-Procedural Neurological Assessment, and Outcome of Carotid Endarterectomy or Stenting

Background: The German-Austrian guideline on the treatment of carotid stenosis recommends specialist neurological assessment (NA) before and after carotid endarterectomy (CEA) or carotid artery stenting (CAS). This study analyzes the determinants of NA and the association of NA with the perioperative rate of stroke or death. Materials and Methods: This study is a pre-planned sub-study of the ISAR-IQ project, which analyzes data from the nationwide German statutory quality assurance carotid database. Patients were classified as asymptomatic (group A), elective symptomatic (group B), and others (group C: emergency (C1), simultaneous operation (C2), and other indications (C3)). The primary outcome event (POE) of this study was any in-hospital stroke or death. Adjusted odds ratios for pre- and post-NA and the POE were calculated using multivariable regression analyses. Results: We analyzed 228,133 patients (54% asymptomatic, 68% male, mean age 72 years) undergoing CEA or CAS between 2012 and 2018. Age and sex were not associated with the likelihood of pre-NA or post-NA. The multivariable regression analysis showed an inverse association between pre-NA and POE (adjusted odds ratio (aOR) 0.47; 95% CI 0.44-0.51, p < 0.001), and a direct association of post-NA and POE (aOR 4.39; 95% CI 4.04-4.78, p < 0.001). Conclusions: Pre- and postinterventional specialist NA is strongly associated with the risk of any in-hospital stroke or death after CEA or CAS in Germany. A relevant confounding by indication or reversed causation cannot be ruled out. Nevertheless, to improve the quality assurance of treatment, the NA recommended in the guideline should be carried out consistently.