Incidence and Outcome of Filter Occlusion during Carotid Artery Stent Procedure Thomas S. Maldonado, 1 Shang Loh, 1 Rodrigo Fonseco, 1 Honesto Poblete, 2 Mark A. Adelman, 1 Neal S. Cayne, 1 Firas Mussa, 1 Caron B. Rockman, 1 Michael Sadik, 2 Sharif Ellozy, 2 and Peter Faries, 2 New York, New York Recent reviews of device-specific complications using neuroprotection have addressed technical difficulties during delivery as well as adverse outcomes, intraoperative and 30-day. Little has been written, however, regarding the relevance of filter occlusion during the carotid stent proce- dure. A retrospective review was conducted of patients undergoing carotid artery stent proce- dures using a variety of neuroprotection devices from 2003 to 2007. Prospective databases from two institutions were examined for incidence and management of filter occlusions during procedures as well as adverse neurological events (intraoperative and 30-day) associated with filter occlusion. There were 283 carotid artery stent procedures performed on 256 patients (163 male, 93 female): 177 (62.5%) arteries were asymptomatic and 106 were symptomatic. Neurological adverse events occurred in six patients (2.1%); three of these resolved completely at 72 hr. Neuroprotection was used in 95% of all patients, and filters were used in 221 stent pro- cedures: Boston Scientific Filter Wire (n ¼ 81), Guidant Accunet (n ¼ 100), Angioguard (n ¼ 17), and Abbot Emboshield (n ¼ 23). Filter occlusion occurred in 11 patients (4.9%) in whom this form of neuroprotection was employed: Angioguard (n ¼ 5), Accunet (n ¼ 2), Emboshield (n ¼ 2), and EPI Filter wire (n ¼ 2). Two of the 11 patients with filter occlusions suffered a neurological event. There was no correlation between filter occlusion and gender, symptoms, stent, or filter type ( p > 0.05). Filter occlusion was managed with export catheter-directed aspiration in seven patients and with prompt filter retrieval in five patients. Filter occlusion is an infrequent event that does not appear to be filter-specific and can be managed successfully by catheter-directed aspiration or filter retrieval. The majority of patients with filter occlusion do not suffer from atheroemboli as a result of this occlusion. INTRODUCTION Carotid artery angioplasty and stenting (CAS) has gained substantial momentum in part due to tech- nological advancement. Tapered stent designs, lower profile delivery system, and the development of embolic protection devices (EPDs) have all con- tributed to the evolution of CAS by allowing for easier and safer delivery and deployment of the stent as well as improving neuroprotection tech- niques. The growing concern over the potential of atheroemboli during CAS has led to the develop- ment and widespread use of EPDs. 1 In fact, prospec- tive trials suggest the use of EPDs is associated with a low procedural complication rate. 2 There are cur- rently three types of EPDs in use: wire-based filters, proximal balloon occlusion with flow reversal, and distal balloon occlusion. Despite the absence of level-one data, there is re- cent literature, including a large meta-analysis, that suggests that EPDs are associated with decreased perioperative adverse events. 3 Furthermore, there appears to be no difference in carotid stenting out- come between any of the three specific EPDs avail- able. 2,4 Apart from all the specific EPD data, there is paucity in the literature regarding the relevance of filter occlusion during CAS. A review of 453 1 Division of Vascular Surgery, New York University School of Med- icine, New York, NY. 2 Division of Vascular Surgery, Mount Sinai School of Medicine, New York, NY. Correspondence to: Thomas Maldonado, Department of Surgery, New York University, 530 First Avenue, Suite 6F, New York, NY 10016, USA, E-mail: thomas.maldonado@nyumc.org Ann Vasc Surg 2008; 22: 756-761 DOI: 10.1016/j.avsg.2008.08.004 Ó Annals of Vascular Surgery Inc. Published online: September 22, 2008 756