Purpose: To examine the predictors and outcomes of asystole in patients who undergo carotid artery stenting (CAS).
Methods: Forty-three patients (24 men; median age 69 years) with asystole were identified after reviewing the case records of 884 patients who underwent CAS at our institution between 1997 and 2009. The control group comprised 678 patients who underwent stenting in the carotid sinus area without asystole. Univariate and multivariate logistic analyses were used to determine the predictors and outcomes of asystole.
Results: A right-sided procedure was more likely to result in asystole [odds ratio (OR) 11.4, 95% CI 4.0 to 32.7, p<0.0001] compared with a left-sided procedure. Patients with a contralateral carotid stenosis (OR 1.7, 95% CI 1.0 to 2.8, p = 0.04) and a left ventricular ejection fraction (LVEF) of <40% (OR 2.2, 95% CI 1.1 to 4.5, p = 0.03) were also more likely to suffer asystole. Smokers appeared less likely to develop asystole (OR 0.25, 95% CI 0.12 to 0.56, p = 0.0006). Periprocedural stroke (14% vs. 1.3%, p<0.001), length of stay during index hospitalization (2.2 vs. 1.2 days, p = 0.002), and 30-day mortality (11.6% vs. 4.1%, p = 0.02) were significantly higher in the asystole group.
Conclusion: Asystole during CAS is more likely to occur in patients undergoing procedures in the right carotid sinus area, in those who have significant contralateral carotid stenosis, and in those with a reduced LVEF. More caution should be exercised during right-sided than left-sided CAS procedures.