Cyanoacrylate adhesive for the closure of truncal veins: 60-day swine model results.

BACKGROUND: The introduction of cyanoacrylate (CA) within a blood vessel triggers polymerization, followed by an inflammatory reaction. METHODS: A sheath was positioned 2.0 cm caudad to the junction of the superficial epigastric and abdominus rectus veins in 2 swine, followed by ultrasound-guided injection of 0.16 mL of CA glue. After glue delivery, the catheter was pulled back 3 cm, compression was applied to the treatment site, and the process was repeated for the entire length. At 60 days postimplantation, the veins were harvested surgically and examined histologically. RESULTS: The histologic changes were consistent with a chronic foreign-body-type inflammatory response. Venous closure, segmental wall thickening, and fibrosis were observed. CONCLUSION: Injection of CA is feasible for closure of superficial veins in animal models. Vein closure is achieved via an inflammatory process which ultimately leads to fibrosis.

The CAPTURE registry: predictors of outcomes in carotid artery stenting with embolic protection for high surgical risk patients in the early post-approval setting.

BACKGROUND: The use of carotid artery stenting with embolic protection has been practiced for over a decade in the United States, and increasingly so since carotid stenting received FDA approval in 2004. While there have been attempts at establishing predictors of outcomes in carotid artery stenting, they have generally been limited to single center experiences and/or multicenter retrospective surveys. This report examines predictors of outcomes in carotid stenting in the earliest and largest prospective multicenter neurologist-adjudicated experience in the United States post device approval. METHODS: The Carotid Acculink/Accunet Post-Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) is a prospective, multi-center registry conducted to assess outcomes of carotid artery stenting (CAS) in the noninvestigational setting following device approval for high surgical risk patients (symptomatic with > or =50% stenosis; asymptomatic > or =80% stenosis). A neurologist examined the patients before the procedure, at 24 hr and 30-days post-procedure. The primary endpoint was a composite of death, any stroke, or myocardial infarction within 30-days post-procedure. Strokes and neurological events suspected to be strokes were adjudicated by an independent Clinical Events Adjudication Committee (CEAC) using prespecified definitions. Logistic regression analysis was performed to determine clinical, procedural, and anatomic predictors of endpoint outcomes. RESULTS: Three thousand five hundred patients were enrolled at 144 sites by 353 physicians of varying specialty backgrounds and CAS experience. The 30-day primary endpoint event rate of death, stroke and MI was 6.3% [95% CI: 5.5-7.1%], and the rate of major stroke and death 2.9% [95% CI: 2.4-3.5]. Predictors of adverse outcomes included age, symptomatic patients, predilation prior to embolic protection device placement, time from symptoms to CAS procedure, and the use of multiple stents. CONCLUSIONS: In general, carotid stenting is performed safely in patients with severe stenosis at high surgical risk, with best outcomes in younger asymptomatic patients. However, there are certain patient and procedural characteristics that are associated with poorer outcomes. In these patients, the risk of stenting should be considered vis-à-vis both the anticipated benefit as well as the alternative surgical and medical options.

The CAPTURE registry: analysis of strokes resulting from carotid artery stenting in the post approval setting: timing, location, severity, and type.

BACKGROUND: Although previous reports of carotid stenting with embolic protection (CAS) have focused on clinical outcomes of death, stroke and myocardial infarction, there are few data available characterizing the strokes that occur during CAS, thus limiting understanding of potential mechanisms. This report examines the timing, location, severity, and type of strokes occurring with CAS in the Carotid ACCULINK/ACCUNET Post Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) study. METHODS: The CAPTURE is a prospective, multicenter registry conducted to assess outcomes of CAS in the postapproval setting after device approval. A neurologist examined the patients before the procedure, at 24 hours and 30 days post-procedure. The primary end point was a composite of death, any stroke, or myocardial infarction within 30 days post-procedure. Strokes and all neurologic events suspected to be strokes were adjudicated by an independent Clinical Events Adjudication Committee using prespecified definitions. Source documents of all patients with strokes in this cohort were reviewed. RESULTS: The 30-day results were available for 3500 patients. The 30-day primary end point event rate of death, stroke, and myocardial infarction was 6.3% (95% confidence interval: 5.5%-7.1%), and the rate of major stroke and death was 2.9% (95% confidence interval: 2.4 to 3.5). 4.8% of patients experienced a stroke (3.9% ipsilateral and 0.9% nonipsilateral, 2% major). A majority of stroke symptoms (57.7%) were noted post-procedure and pre-discharge, whereas 22.3% were noted during the procedure and 20% postdischarge. A similar timing distribution regardless of preprocedural symptomatic status was found.Overall, 41% (69 of 170) of all strokes were major. The incidence of major strokes was statistically significantly greater among symptomatic compared with asymptomatic patients, 4.6% (22 of 482) and 1.6% (47 of 3018), respectively. There were more minor than major strokes in asymptomatic patients (63% vs. 37%; P=0.10), whereas stroke severity was equally distributed in symptomatic patients. Among the ipsilateral strokes, almost half (44%) were major, whereas only one-quarter (26%) of the nonipsilateral strokes were major.Overall, 23% of the major strokes were hemorrhagic and 94% of these strokes were noted on the ipsilateral side. There was a tendency toward more major hemorrhagic strokes in symptomatic than in asymptomatic patients (36% vs. 17%; P=0.07). Fifty-four percent of the strokes post-procedure and pre-discharge were major, whereas 27% of the strokes postdischarge were major. Furthermore, 65% of hemorrhagic strokes were noted post-procedure and pre-discharge, 30% postdischarge. CONCLUSIONS: Strokes related to CAS seem to become clinically apparent after the procedure but before discharge in the majority of events. Nevertheless, a significant minority of stroke symptoms follows discharge from the hospital, typically after 24 hours. Timing of stroke after CAS seems to be similar to timing of stroke after carotid endarterectomy. Moreover, nearly 1 in 5 strokes occur in a nonipsilateral distribution, with the exception of intraprocedural events, which were all ipsilateral to the stent being implanted. Hemorrhagic stroke seemed to be more prevalent in the strokes occurring in the post-procedure period. These descriptors of stroke severity, location, and timing may provide insight in to the mechanistic causes of adverse neurologic outcomes in CAS.

The CAPTURE registry: results of carotid stenting with embolic protection in the post approval setting.

BACKGROUND: Pivotal study data examining carotid stenting with embolic protection as a less invasive alternative to endarterectomy for high surgical risk patients have been acquired under controlled conditions with highly selected physicians and hospitals. This report examines outcomes of carotid stenting post-approval after diffusion of this technology to a broader cross-section of physicians and hospitals. METHODS: The Carotid Acculink/Accunet Post-Approval Trial to Uncover Unanticipated or Rare Events (CAPTURE) is a prospective, multi-center registry to assess two important aspects of the post-IDE experience: the safety of carotid stenting by physicians with varying levels of experience as a measure of the adequacy of physician training, and the identification of rare/unexpected device-related complications. The primary endpoint was a composite of death, any stroke, or myocardial infarction within 30 days post-procedure. RESULTS: 3,500 patients were enrolled by 353 physicians at 144 sites. The 30-day primary endpoint event rate was 6.3% (95% CI: 5.5-7.1%) and did not differ among the three operator experience levels (5.3%, 6.0%, and 7.4%; P = 0.31) from most to least experienced, respectively. There were no differences in outcomes among physician specialties when adjusted for case mix. There were no unanticipated device related adverse events. CONCLUSIONS: The results of the CAPTURE study compare favorably to those achieved in the predicate pivotal investigations, and suggest that the post-approval transfer of this new therapy to the community practice setting via carotid stent training programs is effective in preparing physicians with varying experience levels and specialty training backgrounds.

Establishing an endovascular carotid stent program.

FDA approval of carotid stent and distal protection devices has transformed carotid artery stenting (CAS) from an investigational procedure to a practical application. Recent approval by the Center for Medicare Services (CMS) has ensured that CAS will be a part of everyday practice throughout the country. To establish a competitive endovascular carotid stent program, one needs to develop an effective strategy. The key to success is substance and service. A high-quality clinical program with excellent communication between the patient and referring physician is essential. You must first get access to the patient by establishing a clinical practice. As a radiologist, you have the advantage of gaining access by identifying appropriate patients through noninvasive vascular labs, CTA, and MRA. An algorithm-driven evaluation and treatment protocol with good pre- and postoperative care, along with a quality assurance program, will ensure that your carotid stent program has substance and delivers optimal service. With good planning, you will have a firm clinical foundation for treatment of carotid artery stenosis in your community. Putting all of the ingredients together will ensure a successful carotid endovascular program.