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Self-expanding Nitinol Stent (self-expanding + nitinol_stent)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Experimental evaluation of the JenaClip transcatheter aortic valve,

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2009
Alexander Lauten
Abstract Objective: Transcatheter techniques of aortic valve replacement are a treatment option for valvular heart disease in high-risk surgical candidates. We evaluated a self-expanding valve system with a novel mechanism of fixation in an experimental setting in an acute animal model and ex vivo in aortic root specimens. Method: A self-expanding nitinol stent containing a pericardial tissue valve was implanted in a transapical approach in 15 sheeps. The valve was introduced under fluoroscopic guidance through a 22F sheath by means of a specially designed delivery catheter. Deployment was performed on the beating heart without cardiopulmonary bypass or rapid ventricular pacing and facilitated by positioning feelers anchoring the device to the native aortic cusps. To investigate release and anchoring of the device during retrograde implantation, the stent was also implanted in aortic root specimens obtained from an autopsy series. Results: In animal experiments, stent deployment was primarily successful in 12 (80%) animals. Positioning feelers facilitated implantation by confirming the correct implantation plane of the stent and anchoring to the native aortic cusps. If primary location was not satisfactory the stent was retracted into the catheter and repositioned. After successful implantation no significant changes of hemodynamics were observed. Two animals (13%) developed ventricular fibrillation early in this experimental series due to displacement of one positioning element into a coronary ostium, major regurgitation was observed in two animals. Ex vivo evaluation of the device in aortic root specimens proved feasibility of stent release and leaflet fixation; ex vivo implantation was successful in all cases. Conclusion: .In this study, we demonstrate feasibility of a leaflet-fixation device in nondiseased aortic valves. The JenaClip provides an effective concept of fixation with positioning feelers that allows exact positioning without outflow obstruction and anchoring the valve to the native leaflets. Further studies are necessary to investigate this concept in diseased aortic valves. © 2009 Wiley-Liss, Inc. [source]

Carotid stenting with a new system for distal embolic protection and stenting in high-risk patients: The carotid revascularization with ev3 arterial technology evolution (CREATE) feasibility trial

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2004
Robert D. Safian MD
Abstract The purpose of this study was to evaluate the feasibility of carotid artery revascularization using a new system for carotid stenting and distal embolic protection in 30 patients with severe carotid stenosis and high risk for carotid endarterectomy (Carotid Revascularization With ev3 Arterial Technology Evolution, or CREATE). Previous studies suggest that patients with carotid stenosis and serious comorbid cardiopulmonary and anatomic conditions are at high risk for carotid endarterectomy. All patients underwent percutaneous revascularization using the Protégé GPS self-expanding nitinol stent (ev3, Plymouth, MN) and the Spider distal embolic protection system (ev3). In-hospital and 30-day outcomes were analyzed. High-risk features included age > 75 years (63%), left ventricular ejection fraction < 35% (20%), and restenosis after prior carotid endarterectomy (53%). Procedural success was 100%. In-hospital complications included severe vasovagal reactions in six patients (20%) and a popliteal embolus in one patient (3.3%), treated by successful embolectomy. During 30 days of follow-up, two patients (6.6%) experienced minor neurological deficits, including transient expressive aphasia that resolved without therapy in one patient and homonymous hemianopsia due to contralateral posterior circulation stroke in one patient. This study supports the feasibility of percutaneous carotid artery revascularization with the Protégé GPS self-expanding stent and Spider distal embolic protection system, which will be evaluated in a large multicenter pivotal trial (CREATE Pivotal Trial). Catheter Cardiovasc Interv 2004;63:1,6. © 2004 Wiley-Liss, Inc. [source]

Symptomatic stenosis of the vertebrobasilar arteries: results of extra- and intracranial stent-PTA

EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2009
T. Seifert
Background and purpose:, About half of all transient ischaemic attacks (TIAs) or strokes in the posterior circulation are caused by the arterial stenosis. The purposes of this study were to determine the safety of stent-assisted percutaneous transluminal angioplasty (stent-PTA) and its efficacy for the prevention of recurrent stroke in patients with symptomatic artery stenosis in the extra- and intracranial posterior circulation. Methods:, Forty-six patients with a previous stroke or TIA who received balloon-mounted coronary stents for vertebral artery origin stenosis (VAOS; 29 patients) or self-expanding nitinol stents for vertebrobasilar intracranial stenosis (VBIS; 17 patients) were followed-up for a mean of 24.1 (VAOS) and 12.7 (VBIS) months. Results:, When all cause morbidity/mortality within 30 days from stent-PTA and stroke or death from stroke in the treated vascular territory during the first 12 months of follow-up are combined, the incidence of periprocedural complications and disease progression for the first year is 10.3% in VAOS patients and 17.6% in the VBIS group. Vessel restenosis ,50% was found in 52.0% of VAOS and in 32.1% of VBIS patients who completed 6 months follow-up. Conclusions:, We observed a higher periprocedural complication rate for patients with VBIS and a higher rate of restenosis in VAOS patients after stent-PTA for symptomatic artery stenosis. [source]

Endovascular Interventions in Iliac and Infrainguinal Occlusive Artery Disease

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2004
JOHANNES RUEF M.D., M.Sc.
Percutaneous endovascular procedures are increasingly applied to treat symptomatic peripheral occlusive artery disease. While the primary technical success and recanalization rates in iliac and infrainguinal interventions are high, differences in the long-term patency rates exist with respect to the anatomic localization, separating the iliac, femoropopliteal, and infrapopliteal arterial regions. In iliac arteries, even complex lesions can be recanalized with good long-term patency rates, especially when using self-expanding nitinol stents. In the infrainguinal arteries the method of choice is still under debate (e.g., balloon angioplasty vs stent implantation). A high restenosis rate represents one of the major limitations in femoropopliteal and infrapopliteal interventions. Therefore, additional methods and treatment strategies for peripheral interventions with the potential for future applications are under investigation and will be discussed such as drug-eluting stents, brachytherapy, subintimal angioplasty, laser angioplasty, atherectomy/thrombectomy, cutting balloon, polytetrafluoroethylene (PTFE)-covered stent grafts, biodegradable stents, and cryoplasty. The increasing amount of data on successful peripheral interventions supports the necessity to adapt and reevaluate the current consensus guidelines that were put together in 2000. [source]