Risk Factors for Cerebral Hyperperfusion Syndrome following Carotid Revascularization

Introduction Cerebral hyperperfusion syndrome (CHS) is a rare but known complication of carotid revascularization that can result in severe postoperative disability and death. CHS is a well-described sequela of carotid endarterectomy (CEA) and, more recently, of transfemoral carotid artery stenting (TFCAS), but its incidence after transcarotid artery revascularization (TCAR) has not been delineated. The aims of this study were to determine the impact of procedure type (CEA vs. TCAR vs. TFCAS) on the development of CHS, as well as to identify perioperative risk factors associated with CHS. Methods The Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) was queried for patients aged ≥18 years who underwent CEA, TCAR, or TFCAS from 2015-2021. Emergent procedures were excluded. The primary outcome was postoperative development of CHS, defined as the presence of postoperative seizures, intracerebral hemorrhage due to hyperperfusion, or both. Bivariate and multivariable logistic regression analyses were performed to identify factors associated with CHS. Results 156,003 procedures were included (72.7% CEA, 12.4% TCAR, 14.9% TFCAS). The incidence of CHS after CEA, TCAR, and TFCAS were 0.15%, 0.18%, and 0.53%, respectively. There was no significant difference in risk of CHS after TFCAS compared to CEA, (OR: 1.21; 95% CI 0.76-1.92); P = 0.416), nor was there a difference between TCAR and CEA (OR: 0.91; 95% CI 0.57-1.45; P = 0.691) (Table 4). . Perioperative risk factors associated with an increased risk of CHS included previous history of transient ischemic attack (TIA) or stroke (OR: 2.50; 95% CI 1.69-3.68; P < .0001), necessity for urgent intervention within 48 hours (OR: 2.03; 95% CI 1.43-2.89; P < .0001), treatment of a total occlusion (OR: 3.80; 95% CI 1.16-12.47; P = 0.028), and need for postoperative intravenous (IV) blood pressure medication (OR: 5.45; 95% CI 3.97-7.48; P < .0001). Age, preoperative hypertension, degree of ipsilateral stenosis less than or equal to 99%, and history of prior carotid procedure were not statistically associated with an increased risk of CHS. Discharging patients on an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) was associated with a decreased risk of developing CHS (OR: 0.47; 95% CI 0.34-0.65; P < .0001). Conclusions Compared with CEA, TCAR and TFCAS were not statistically associated with an increased risk of postoperative CHS. Patients with a previous history of TIA or stroke, who require urgent intervention or postoperative IV blood pressure medication, or who are treated for a total occlusion are at a higher risk of developing CHS. Using an ACEI/ARB on discharge appears to be protective against CHS and should be considered for the highest risk patients.