Introduction: During the past decade, novel intra-procedural carotid artery stenting (CAS) techniques have emerged. Primary stenting, which forgoes the use of any angioplasty, and proximal embolic protection have been utilized in an attempt to mitigate perioperative complications. However, the effectiveness of such techniques remains controversial. We sought to assess the effect of primary stenting, proximal embolic protection, comorbidities, medications and other patient-level factors on outcomes of CAS in a multispecialty national database.
Methods: We analyzed all CAS cases in the Vascular Quality Initiative (VQI) database from 2005 to 2015. Only patients with a follow up of ≥30 days were included. Propensity score matching was used to assess the effect of primary stenting on primary composite end-point outcome of stroke/transient ischemic attack (TIA)/death within 30 days of the procedure. A logistic regression model was constructed to determine the effect proximal protection and other characteristics had on 30-day stroke/TIA/death.
Results: A total of 3,584 patients satisfied our selection criteria (mean age was 69.5±9.9 years; males 62%). Composite perioperative stroke/TIA/death rate was 9.7% (stroke 5.5%; TIA 2.4%; death 2.8%) and new myocardial infarction rate was 1.2%. Primary carotid stenting technique was used in 213(6.0%) patients, while proximal embolic protection was utilized in only 132(4.0%) patients. In a well-matched cohort of 211 primary stenting patients (total 422 patients): the 30-day stroke/TIA/death rate was almost double in the treated cohort (13.2% vs 7.1%, P<0.05), while 30-day stroke/death rate was 4.6% higher in the primary stenting group (10.7% vs 6.1%, P=0.10). Proximal embolic protection had no significant effect on primary composite end-point (OR 0.68, P=NS), while P2Y12 antagonist use and a history of ipsilateral CEA each had approximately 30% reduction in risk of stroke/TIA/death (OR 0.71, P=0.03; OR 0.68, P=0.02).
Conclusion: Primary carotid stenting carries a higher risk of perioperative stroke/TIA/death in CAS than traditional use of angioplasty. Proximal embolic protection has no significant effect on outcomes while P2Y12 antagonists and having a prior CEA reduce the chances of stroke/TIA/death.