The capture of visible debris by distal cerebral protection filters during carotid artery stenting: Is it predictable?
ABSTRACT Neurologic complications during carotid artery stenting (CAS) are most clearly associated with embolization of visible debris. Distal filter devices may provide cerebral protection by capturing clinically significant debris. However, they increase procedural time and expense and have their own set of complications. The current study was undertaken to identify the clinical factors predictive for the presence or absence of visible debris captured by distal filter devices during CAS.
Patients undergoing CAS with use of a distal filter device (n = 279) were prospectively entered into an investigational carotid registry. Recorded variables were classified as patient-, lesion-, or procedure-related. The filter was assessed for visible debris in each case. The odds ratio (OR) and 95% confidence interval (CI) were determined for each variable to predict visible debris. The ability of each variable to predict the absence of visible debris was assessed by calculating the individual negative predictive value (NPV).
Visible debris was present in 169 filters (60.3%). There was an increased risk of visible debris found with several variables (OR, 95% CI): hypertension (2.9, 1.7 to 5.2), hypercholesterolemia (2.3, 1.4 to 3.9), stent diameter >9 mm (16.6, 9.0 to 30.0), and any neurologic event (4.2, 1.5 to 9.9). The NPV failed to exceed 0.80 (80%) for any variable. The NPV of the variables with a significantly elevated OR was as follows: hypertension (0.60), hypercholesterolemia (0.52), stent diameter >9 mm (0.75), and any neurologic event (0.38).
Several clinical variables are associated with the presence of visible debris captured by distal filter devices. The current study failed to identify any variables capable of consistently predicting the absence of visible debris. These findings support the routine rather than the selective use of cerebral protection during CAS.
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ABSTRACT: Carotid artery stenting has emerged as an alternative to carotid endarterectomy for the treatment of severe extracranial carotid stenosis in patients with anatomic or clinical factors that increase their risk of complications with surgery, yet there remains a substantial amount of variability and uncertainty in clinical practice in the referral of patients for stenting vs endarterectomy. By undertaking a thorough review of the literature, we sought to better define which subsets of patients with "high-risk" features would be likely to preferentially benefit from carotid stenting or carotid endarterectomy. Although only a single randomized trial comparing the outcomes of carotid stenting with distal protection and endarterectomy has been completed, a wealth of observational data was reviewed. Relative to endarterectomy, the results of carotid stenting seem favorable in the setting of several anatomic conditions that render surgery technically difficult, such as restenosis after prior endarterectomy, prior radical neck surgery, and previous radiation therapy involving the neck. The results of stenting are also favorable among patients with severe concomitant cardiac disease. Carotid endarterectomy, alternatively, seems to represent the procedure of choice among patients 80 years of age or older in the absence of other high-risk features. Overall, existing data support the concept that carotid stenting and endarterectomy represent complementary rather than competing modes of therapy. Pending the availability of randomized trial data to help guide procedural selection, which is likely many years away, an objective understanding of existing data is valuable to help select the optimal mode of revascularization therapy for patients with severe carotid artery disease who are at heightened surgical risk.Journal of Vascular Surgery 10/2006; 44(3):661-72. · 3.21 Impact Factor