Patients Undergoing Carotid Stenting Research Articles

Retinal embolization during carotid angioplasty and stenting: mechanisms and role of cerebral protection systems.

Carotid stenting has become an accepted alternative to endarterectomy, but fear of embolic stroke has impeded its generalized application. The retina provides a unique observatory for the study of emboli, which may occur either directly or indirectly via collaterals to the ophthalmic artery. Systems under development for cerebral protection differ in their capacity to trap small emboli and in their protection of the collateral circulation. We evaluated 118 sequential patients undergoing carotid stenting using fundoscopy, fluorescein retinal angiography, and visual field examination. The site and size of emboli was assessed, and degree of edema estimated. All patients were treated using distal protection during carotid stent implantation: 38 patients with the Théron system (using routine flushing toward the external carotid) and 80 patients with the Percusurge system (aspiration only). Retinal embolization occurred in 6 of the 118 patients (4%), of whom 2 were symptomatic (1.7%). Using the Théron system, 5 of 38 patients (13.2%) had emboli while 1 of 80 (1.25%) had emboli using the Percusurge system (P = 0.019). Symptoms occurred only with emboli >20 microm. Symptomatic retinal embolization is uncommon during carotid stenting, but is more likely when external to internal carotid collaterals are not protected. Cerebral protection system designs should take into consideration the existence of collaterals and the need to protect against smaller sized emboli, which may cause blindness in the retinal circulation.

The 27th International Stroke Conference San Antonio, Texas, February 7-9, 2002.

The 27th International Stroke Conference San Antonio, Texas, February 7-9, 2002.

Immediate and Late Clinical Outcomes of Carotid Artery Stenting in Patients With Symptomatic and Asymptomatic Carotid Artery Stenosis: A 5-Year Prospective Analysis

To the Editor: In a recent article, Roubin et al 1 performed a prospective analysis of the experience of a single group of operators to establish the immediate and late stroke rates in a series of symptomatic and asymptomatic patients undergoing carotid stenting (CS). In our opinion, the authors’ conclusions that CS carries an acceptable 30-day complication rate and that it is comparable with carotid endarterectomy (CEA) may be misleading. If we analyze the results with respect to the indications for CS, although symptomatic and asymptomatic patients had similar periprocedural complication rates after CS, the incidence of perioperative events was 8.2% (26/317) in symptomatic patients and 6.5% (19/287) in asymptomatic patients: both values exceed the recommended upper limits for perioperative risk and mortality rates supporting the beneficial effects of CEA in symptomatic and asymptomatic patients.2 Moreover, the periprocedural complication rate among symptomatic patients (8.2%) was more than twice as high as with surgery according to 20 …

Vein graft stenosis: A personal approach

To determine the clinical significance of acute hemodynamic disturbances during stenting in the carotid sinus region, we assessed the relation between intraprocedural changes in heart rate (HR) and blood pressure (BP) and adverse neurologic and cardiac outcomes. Eighteen patients underwent carotid stenting with the Wallstent (Schneider Inc). Suitable candidates had at least 60% diameter stenosis of the carotid artery by angiography. Initial and nadir HR and BP were recorded during the predilatation, stent delivery, and postdilatation periods. Bradycardia was defined as HR ≤60 beats/min and hypotension as systolic BP ≤100 mm Hg. Nineteen Wallstents were successfully deployed in all 19 carotid arteries. Some degree of bradycardia or hypotension occurred in 68% of carotid stent procedures, but administration of vasoactive medications was necessary in only 7 patients (37%) with more persistent hemodynamic disturbances. Hypotension or the need for continuous vasopressor therapy was significantly more common during postdilatation (32%) than in the predilatation period (5%) (p = 0.02). Bradycardia was not reduced by prophylactic atropine. In 1 patient the hemodynamic response to stenting may have contributed to an adverse neurologic and cardiac outcome. Thus, despite frequent fluctuations in HR and BP, most carotid stenting procedures were performed with excellent overall results, even in patients at high risk.

Acute hemodynamic changes during carotid artery stenting

To determine the clinical significance of acute hemodynamic disturbances during stenting in the carotid sinus region, we assessed the relation between intraprocedural changes in heart rate (HR) and blood pressure (BP) and adverse neurologic and cardiac outcomes. Eighteen patients underwent carotid stenting with the Wallstent (Schneider Inc). Suitable candidates had at least 60% diameter stenosis of the carotid artery by angiography. Initial and nadir HR and BP were recorded during the predilatation, stent delivery, and postdilatation periods. Bradycardia was defined as HR ≤60 beats/min and hypotension as systolic BP ≤100 mm Hg. Nineteen Wallstents were successfully deployed in all 19 carotid arteries. Some degree of bradycardia or hypotension occurred in 68% of carotid stent procedures, but administration of vasoactive medications was necessary in only 7 patients (37%) with more persistent hemodynamic disturbances. Hypotension or the need for continuous vasopressor therapy was significantly more common during postdilatation (32%) than in the predilatation period (5%) (p = 0.02). Bradycardia was not reduced by prophylactic atropine. In 1 patient the hemodynamic response to stenting may have contributed to an adverse neurologic and cardiac outcome. Thus, despite frequent fluctuations in HR and BP, most carotid stenting procedures were performed with excellent overall results, even in patients at high risk.