Plaque Characteristics on CT Angiography Do Not Improve the Ability to Predict Hemodynamic Instability During and After Carotid Angioplasty and Stenting

Background: Hemodynamic instability is commonly seen during carotid angioplasty and stenting. Although prophylactic treatment with anticholinergics is beneficial, selected use in high-risk patients is desirable. This study examines whether plaque characteristics on computed tomography angiography in addition to demographic factors improve predictive capability.

Methods: We retrospectively collected information from 298 carotid angioplasty procedures between January 2013 and December 2018. Nine individuals were excluded due to a previous ipsilateral endarterectomy. Our primary outcome was a decrease of 20% or more in heart rate or blood pressure at angioplasty. Data were analyzed using χ2 tests and regression statistics.

Results: Of the 289 patients included for analysis, 57 had intraoperative instability and 26 had postoperative instability. Radiologist interpretation was found to have a risk ratio of 1.63 (95% confidence interval: 1.00-2.65) for intraoperative instability (P=0.080). Intraoperative instability was significantly associated with subsequent postoperative instability (P=0.005). Our regression model included previous endarterectomy and diabetes as predictive factors with a sensitivity of 11.3% and a specificity of 100.0%. Anticholinergic usage was associated with hypotension without coexisting bradycardia with a risk ratio of 2.36 (95% confidence interval: 1.06-5.26; P=0.047).

Conclusions: Individuals without a previous contralateral endarterectomy and/or history of diabetes are at lower risk of hemodynamic instability. The addition of computed tomography angiographic variables does not improve this prediction. Future prospective, randomized work is required to improve our ability to identify and treat individuals at high risk of instability during carotid angioplasty and stenting.