nitinol and Stroke

Atrial fibrillation (AF) is a major cause of stroke and systemic embolism. Although warfarin and the novel oral anticoagulants reduce thromboembolic risk, they are associated with an ongoing bleeding hazard, in addition to other limitations that deter their use. The left atrial appendage (LAA) appears to be the primary source of thrombus in AF; therefore, LAA closure represents a mechanical strategy for stroke prevention in these patients. The WATCHMAN™ LAA closure device (Boston Scientific, Natick, MA) is a nitinol-framed occluder that is implanted percutaneously under echocardiographic and fluoroscopic guidance. Data from two randomized clinical trials support the clinical efficacy of transcatheter LAA occlusion with the WATCHMAN and demonstrate that procedural safety has improved significantly since initial experience. This article summarizes the rationale, procedural technique, safety, and clinical efficacy of the WATCHMAN device in patients with AF at high risk for thromboembolic events.

Topics: Alloys; Atrial Appendage; Atrial Fibrillation; Cardiac Catheterization; Echocardiography, Transesophageal; Equipment Design; Humans; Predictive Value of Tests; Radiography, Interventional; Stroke; Thromboembolism; Treatment Outcome

In patients with non-valvular atrial fibrillation, efficacy of stroke prevention with oral anticoagulant therapy has been proved. Despite their high risk for thromboembolic events, there are substantial numbers of patients who are not candidates for long-term oral anticoagulant therapy, therefore the interest in alternative treatment strategies are in focus these days. The most common place within the heart for thrombus formation in patients with non-valvular atrial fibrillation is the left atrial appendage. Two devices specifically designed for percutaneous left atrial appendage closure are currently available in Europe: the WATCHMAN LAA system (Atritech, Inc) and the AMPLATZER Cardiac Plug (AGA Medical Corporation). Although present trial results (PLAATO, PROTECT AF) suggest that LAA closure may be performed at acceptable safety and it may reduce the long-term stroke risk, available data are still very limited. At present these procedures may be an acceptable alternative in selected high-risk patients with non-valvular atrial fibrillation who are not or suboptimal candidates for oral anticoagulant therapy. On 28. January, 2010 we performed the first three successful percutaneous left atrial appendage closure procedures in Gottsegen György Hungarian Institute of Cardiology in Hungary.

Topics: Administration, Oral; Aged; Alloys; Anticoagulants; Atrial Appendage; Atrial Fibrillation; Cardiac Surgical Procedures; Clinical Trials as Topic; Contraindications; Echocardiography, Transesophageal; Female; Heart Diseases; Humans; Hungary; Male; Middle Aged; Prosthesis Design; Radiography; Risk Assessment; Risk Factors; Septal Occluder Device; Stents; Stroke; Thoracoscopy; Thrombosis; Treatment Outcome

The primary purpose of this study was the composite of major adverse events through 30 days post-index procedure or ipsilateral stroke from 30 days to 1 year (365 days). Presented here is the composite of death, stroke, and myocardial infarction (MI) through 30 days.. Rates of minor stroke have been higher with carotid artery stenting (CAS) compared with carotid endarterectomy (CEA). The study hypothesized that a stent with mesh covering may improve plaque stabilization during CAS, reduce plaque protrusion, and lead to reduced stroke rates.. The SCAFFOLD trial, a prospective, multicenter, single-arm clinical trial evaluating the GORE carotid stent (GCS), enrolled patients at increased risk for adverse events from CEA with severe carotid artery stenosis (defined as symptomatic ≥50% or asymptomatic ≥80%). The SCAFFOLD trial screening committee was implemented to determine adherence to the study protocol. Patients were evaluated for the primary endpoint, the composite of death, stroke, and MI through 30 days.. A total of 312 patients were enrolled, treated, and reviewed by the SCAFFOLD trial screening committee, of which 265 were included in the primary analysis population. The 30-day rate of death, stroke, or MI was 3.0% (95% confidence interval: 1.3% to 5.9%) and the stroke or death rate was 1.5%. The 30-day stroke rate was 1.1%. The 2 deaths in the study were not stroke related.. Low death, stroke, or MI rates were demonstrated with GCS in patients at high risk for CEA. The 30-day stroke rate of 1.1% suggests that the carotid stent mesh covering may reduce the neurologic events associated with CAS when used in appropriately selected patients.

Topics: Aged; Aged, 80 and over; Alloys; Carotid Stenosis; Endarterectomy, Carotid; Endovascular Procedures; Female; Humans; Male; Middle Aged; Myocardial Infarction; Prospective Studies; Prosthesis Design; Risk Assessment; Risk Factors; Self Expandable Metallic Stents; Severity of Illness Index; Stroke; Time Factors; Treatment Outcome; United States

This study aimed to evaluate the safety and performance of the TriGuard™ Embolic Deflection Device (EDD), a nitinol mesh filter positioned in the aortic arch across all three major cerebral artery take-offs to deflect emboli away from the cerebral circulation, in patients undergoing transcatheter aortic valve replacement (TAVR).. The prospective, multicentre DEFLECT I study (NCT01448421) enrolled 37 consecutive subjects undergoing TAVR with the TriGuard EDD. Subjects underwent clinical and cognitive follow-up to 30 days; cerebral diffusion-weighted magnetic resonance imaging (DW-MRI) was performed pre-procedure and at 4±2 days post procedure. The device performed as intended with successful cerebral coverage in 80% (28/35) of cases. The primary safety endpoint (in-hospital EDD device- or EDD procedure-related cardiovascular mortality, major stroke disability, life-threatening bleeding, distal embolisation, major vascular complications, or need for acute cardiac surgery) occurred in 8.1% of subjects (VARC-defined two life-threatening bleeds and one vascular complication). The presence of new cerebral ischaemic lesions on post-procedure DW-MRI (n=28) was similar to historical controls (82% vs. 76%, p=NS). However, an exploratory analysis found that per-patient total lesion volume was 34% lower than reported historical data (0.2 vs. 0.3 cm3), and 89% lower in patients with complete (n=17) versus incomplete (n=10) cerebral vessel coverage (0.05 vs. 0.45 cm3, p=0.016).. Use of the first-generation TriGuard EDD during TAVR is safe, and device performance was successful in 80% of cases during the highest embolic-risk portions of the TAVR procedure. The potential of the TriGuard EDD to reduce total cerebral ischaemic burden merits further randomised investigation.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Valve; Aortic Valve Stenosis; Brain Ischemia; Brazil; Cardiac Catheterization; Cognition; Cognition Disorders; Diffusion Magnetic Resonance Imaging; Embolic Protection Devices; Europe; Female; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Intracranial Embolism; Male; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Risk Factors; Severity of Illness Index; Stroke; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Transcranial

This study sought to evaluate the feasibility of the CGuard Carotid Embolic Protective Stent system-a novel thin strut nitinol stent combined with a polyethylene terephthalate mesh covering designed to prevent embolic events from the target lesion in the treatment of carotid artery lesions in consecutive patients suitable for carotid artery stenting.. The risk of cerebral embolization persists throughout the carotid artery stenting procedure and remains during the stent healing period.. A total of 30 consecutive patients (age 71.6 ± 7.6 years, 63% male) meeting the conventional carotid artery stenting inclusion criteria were enrolled in 4 centers in Germany and Poland.. The primary combined endpoint was the procedure success of the CGuard system and the number and volume of new lesions on the ipsilateral side assessed by diffusion-weighted magnetic resonance imaging at 48 h post-procedure and at 30 days. The secondary endpoint was 30-day major adverse cardiac or cerebrovascular events (death, stroke, or myocardial infarction). Protection devices were used in all procedures. Procedure success was 100%, with 0% procedural complications. The 30-day major adverse cardiac or cerebrovascular events rate was 0%. New ipsilateral ischemic lesions at 48 h occurred in 37.0% of patients and the average lesion volume was 0.039 ± 0.08 cm(3). The 30-day diffusion-weighted magnetic resonance imaging showed complete resolution of all but 1 periprocedural lesion and only 1 new minor (0.116 cm(3)) lesion in relation to the 48-h scan.. The use of the CGuard system in patients undergoing carotid artery stenting is feasible. In addition, the benefit of using CGuard may extend throughout the stent healing period.

Topics: Aged; Alloys; Angioplasty; Carotid Artery Diseases; Diffusion Magnetic Resonance Imaging; Embolic Protection Devices; Feasibility Studies; Female; Germany; Humans; Intracranial Embolism; Male; Middle Aged; Poland; Polyethylene Terephthalates; Prospective Studies; Prosthesis Design; Risk Factors; Stents; Stroke; Surgical Mesh; Time Factors; Treatment Outcome

Thromboembolism due to atrial fibrillation (AF) is a frequent cause of stroke. More than 90% of thrombi in AF form in the left atrial appendage (LAA). Obliteration of the appendage may prevent embolic complications.. We evaluated the feasibility and safety of implanting a novel device for percutaneous left atrial appendage transcatheter occlusion (PLAATO). LAA occlusion using the PLAATO system was attempted in 15 patients with chronic AF at high risk for stroke, who are poor candidates for long-term warfarin therapy. The implant consists of a self-expanding nitinol cage covered with a polymeric membrane (ePTFE). The LAA was successfully occluded in 15/15 patients (100%). Angiography and transesophageal echocardiography (TEE) during the procedure showed that the device was well-seated in all patients and that there was no evidence of perforation, device embolization, or interference with surrounding structures. In 1 patient, the first procedure was complicated by a hemopericardium, which occurred during LAA access. A second attempt 30 days later was successful with no untoward sequela. No other complications occurred. At 1-month follow-up, chest fluoroscopy and TEE revealed continued stable implant position with smooth atrial-facing surface and no evidence of thrombus.. Thus, transcatheter closure of the LAA is feasible in humans. This novel implant technology may be appropriate for patients with AF who are not suitable candidates for anticoagulation therapy. Further trials are needed to show the long-term safety and its efficacy in reducing stroke.

Topics: Alloys; Atrial Appendage; Atrial Fibrillation; Cardiac Catheterization; Coronary Angiography; Feasibility Studies; Humans; Polytetrafluoroethylene; Prostheses and Implants; Skin; Stroke; Thromboembolism

Pericardial effusion or pericardial tamponade (PE/PT) is a relatively common complication of left atrial appendage closure (LAAC). However, delayed PE/PT is rare with limited data. The aim of the study was to analyze the incidence and clinical consequences of delayed PE/PT following LAAC.. Patients with nonvalvular AF who were successfully implanted with LAAC devices from October 2014 to April 2021 were consecutively screened. Subjects experiencing delayed PE/PT after LAAC were included. All treatment sessions of the subjects were recorded in detail. After discharge, the patients were followed up for clinical outcomes.. A total of 748 patients with successful LAAC [nitinol cage device (475 Watchman 2.5), nitinol plug device (131 ACP and 142 LAmbre)] were screened. Six patients experienced delayed PE/PT (1 Watchman, 2 ACP, 3 LAmbre). The incidence of delayed PE/PT was higher in patients with a nitinol plug device (1.8% vs. 0.2%, P = 0.027). Bloody PE only occurred in patients with a nitinol plug device (5/273, 1.8%). All the patients accepted pericardiocentesis and discontinuing antithrombotic medication, and none of the patients died or needed cardiac surgery. All patients were followed up for 810 (598, 1174) days after discharge. None of them developed constrictive pericarditis or thromboembolic or major bleeding events.. Delayed PE/PT is rare but can occur, and the incidence of delayed bloody PE/PT for the nitinol plug device was higher than that for the nitinol cage device. The strategy of emergency pericardiocentesis combined with discontinuing antithrombotic medication may be effective for delayed bloody PE/PT.

Topics: Atrial Appendage; Atrial Fibrillation; Cardiac Surgical Procedures; Fibrinolytic Agents; Humans; Pericardial Effusion; Stroke; Treatment Outcome

To evaluate patients characteristics, procedural details, perioperative outcomes, and midterm results of carotid artery stenting (CAS) performed with the Roadsaver/Casper stent (Terumo Corp, Tokyo, Japan) as compared to concurrent patients treated with other commercially available carotid stents.. This is a single-center, retrospective, nonrandomized study including 200 consecutive patients who underwent a total of 205 elective CAS procedures due to severe internal carotid artery stenosis between April 2015 and December 2018. Procedural data and outcomes for patients treated with the Roadsaver/Casper stent implantation (100 procedures, in 97 patients) vs first-generation carotid stents implantations (90 procedures, in 88 patients) were compared. Fifteen patients were treated with CGuard carotid stent (InspireMD, Tel Aviv, Israel), and outcomes were reported separately. Primary endpoints were the occurrence of major adverse cerebrovascular events (MACE), including death, ipsilateral stroke, and transitory ischemic attack (TIA). Secondary endpoints were the rate of intrastent stenosis, the need for reintervention, and the occurrence of adverse cardiovascular events, including myocardial infarction, arrhythmias, and need for inotropic support.. No difference in demographics and preoperative risk factors were observed between patients treated with and without the Roadsaver/Casper stent. The mean procedure time was shorter in the Roadsaver/Casper group (40.7±16.9 vs 49.4±27.3 minutes; p=0.008), while radial percutaneous access was more frequent (24% vs 5%; p<0.001). The rate of stroke/TIA/death at 30 days was 3% in the Roadsaver group vs 1% in the first-generation stent group (p=0.623). The primary patencyrate was 100% and 93.4% at 1- and 3-year of follow-up in the Roadsaver/Casper groupand 99% and 94.3% in the other stent group, respectively (p=0.95).. In this real-world cohort of patients undergoing CAS, the Roadsaver/Casper stent was used to treat more symptomatic and vulnerable carotid plaques as compared to other carotid stents. Nevertheless, patients treated with this low-profile dual-layer micromesh stent showed low events rates at both 30 days and follow-up, similar to that observed for other stents.

Topics: Alloys; Carotid Arteries; Carotid Stenosis; Humans; Retrospective Studies; Risk Factors; Stents; Stroke; Treatment Outcome

To describe our initial experience with the Versi Retriever for mechanical thrombectomy in patients with acute ischemic stroke.. This study is a single-center, single-arm, first-in-man registry under institutional review board control to evaluate the efficacy and safety of the new stent retriever, the Versi Retriever. Patients with acute ischemic stroke were consecutively enrolled between September and November 2017. The clinical and procedural data were retrospectively analyzed. The angiographic result after the procedure was self-graded based on the Thrombolysis in Cerebral Infarction (TICI) scale by each operator.. Eleven patients with a mean age of 69.4 years were treated with the Versi Retriever. Median National Institutes of Health Stroke Scale score on admission was 16 (IQR 10-34). The occluded vessel was located in the anterior circulation in 81.8%. Revascularization rates of TICI 2b-3 and TICI 3 at final angiogram were achieved in 100% and 63.6%, respectively. A favorable functional outcome (modified Rankin Scale 0-2) at 90 days was obtained in 72.7%. No symptomatic intracranial hemorrhage occurred and no procedure-related complication was observed.. Our initial experience suggests that the Versi Retriever is a safe and effective stent retriever for mechanical thrombectomy in patients with acute ischemic stroke.. NCT03366818.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Angiography; Brain Ischemia; Drug-Eluting Stents; Female; Humans; Male; Middle Aged; Registries; Retrospective Studies; Stroke; Thrombectomy; Treatment Outcome; Young Adult

Stroke due to the release of embolic debris during the placement of a stent to correct carotid artery stenosis is a constant procedural and peri-procedural threat. The new all metal Casper stent has been created with two layers of nitinol, the inner layer of which has pores diminutive enough to prevent embolic release.. To evaluate the safety, effectiveness, and utility of the double layer nitinol Casper carotid artery stent in the treatment of patients with severe carotid artery stenosis.. 19 patients with severe internal carotid artery stenosis, 14 symptomatic and 5 asymptomatic, were treated with the Casper stent. After stent placement, angiographic and cone beam CT images were recorded in all patients.. The unique low profile delivery system allowed for easy stent placement, re-sheathing, and repositioning of the stent. The large cell external layer produced excellent apposition to the artery wall. The inner layer prevented prolapse of atherosclerotic debris through the device. Plaque coverage was achieved; residual stenosis ranged from 0% to 20%. Long term angiographic follow-up in 5 patients showed wall apposition of the device covering the lesion and no restenosis. There were no procedure related complications. Two patients experienced a delayed ischemic stroke, likely related to inconsistent medical management.. The Casper has been an excellent stent for the treatment of internal carotid artery stenosis and its internal micromesh layer has been effective in preventing plaque prolapse. It provides the flexibility of large cell stents and the inner layer provides maximum protection against plaque prolapse.

Topics: Aged; Aged, 80 and over; Alloys; Carotid Stenosis; Embolism; Female; Humans; Male; Middle Aged; Prosthesis Design; Stents; Stroke; Surgical Mesh; Treatment Outcome

Mechanical thrombectomy (MTB) is a treatment of reference for acute ischemic stroke due to large brain vessel occlusion but some concerns remain about its use in small distal branches. In the present study, we assessed the efficacy and the safety of distal MTB using the Catch Mini (CM) stent retriever.. We retrospectively reviewed a prospectively maintained database of all consecutive patients who underwent MTB for a distal intracranial occlusion with the Catch Mini device at our hospital.. Forty-one patient underwent MTB for distal intracranial occlusions using the CM stent retriever. Good capillary reperfusion (TICT≥2b) was observed in 32 out of 41 patients (78%). Focal ischemia within the territory vascularized by the artery addressed by the CM was observed in 8 patients (19.5%). Post-procedural vasospasm was observed in 8 patients, all responding rapidly to vasodilatator administration. Two asymptomatic hemorrhages (4.9%) were noted on follow-up imaging (one patechial hemorrhage and one parenchymal hematoma) in patients with M2 occlusions. No vessel rupture were observed. Overall, good neurological outcome at three months (mRS≤2) was observed in 28 (out of 34 patients followed; 82.4%) of patients.. Our single-center experience shows that the CM stent retriever is safe and effective for the recanalization of small diameter distal branches feeding eloquent brain areas.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Alloys; Brain Ischemia; Device Removal; Female; Humans; Male; Middle Aged; Radiography, Interventional; Retrospective Studies; Stents; Stroke; Thrombectomy; Treatment Outcome

 Various stent retrievers differing in stent design and mechanical properties are currently available for the treatment of ischemic stroke. We conducted this in vitro study to compare the efficacy, embolism rate, and safety of commercially available stent retrievers and prototypes..  Whole blood thrombi were produced in a Chandler loop. The thrombi were inserted into the curved M1 segment of a silicone model of the anterior cerebral circulation. Thrombectomy maneuvers were performed with six commercially available stent retrievers and 2 prototypes with different strut thickness. Wall-stent apposition, first pass recanalization rate, retraction force, and embolism rate were compared..  Devices with complete wall-stent apposition had the highest first pass recanalization rate and lowest embolism rate, but showed the highest retraction force. The prototype with thinner struts had a comparable recanalization and embolism rate, while a lower retraction force had to be applied compared to the prototype with thicker struts..  Complete wall-stent apposition facilitates a higher recanalization rate and lower embolism rate but also correlates to a higher necessary retraction force and thus possibly higher risk of endothelium damage. Stent modifications leading to a reduced retraction force do not compromise efficacy and embolism rate..   · Complete wall-stent apposition facilitates an effective thrombectomy. · Complete wall-stent apposition leads to higher retraction force and possibly greater endothelium damage. · Modifications of strut thickness do not compromise recanalization and embolism rate. · Thinner struts correlate with a lower retraction force.. · Larsen N, Oberbeck K, Lima de Miranda R et al. Comparison of Efficacy, Embolism Rate and Safety of Thrombectomy with Stent Retrievers in an Anterior Circulation Stroke Model. Fortschr Röntgenstr 2018; 190: 1053 - 1058.. ZIEL:  In der Therapie des ischämischen Schlaganfalles kommen verschiedene Stentretriever zum Einsatz, die sich in Stentdesign und mechanischen Eigenschaften unterscheiden. Wir führten diese in vitro-Studie durch, um Effektivität, Embolisationsrate und notwendige Retraktionskraft von kommerziell erhältlichen Stentretrievern und zwei Prototypen zu vergleichen..  In einem Chandler loop generierte Vollblutthromben wurden in das bogig verlaufende M1-Segment eines Silikonmodells der vorderen intrakraniellen Zirkulation eingebracht. Thrombektomiemanöver wurden mit 6 kommerziell erhältlichen Stentretrievern und 2 Prototypen, die sich in der Stärke der Stentstreben unterschieden, durchgeführt. Die Adaptation des Stentretrievers an die Gefäßwand, first pass-Rekanalisierungsrate, Retraktionskraft und Embolisationsrate wurden verglichen..  Die Stentretriever, die eine vollständige Adaptation an die Gefäßwand zeigten, wiesen eine höhere first pass-Rekanalisierungsrate und geringere Embolisationsrate auf als Stentretriever, die sich nicht in voller Länge an die Gefäßwand anlegten. Andererseits war bei ersteren eine höhere Retraktionskraft notwendig. Der Prototyp mit dünneren Stentstreben erreichte eine vergleichbare Rekanalisations- und Embolierate bei geringerer aufzuwendender Retraktionskraft im Vergleich zum Prototypen mit stärkeren Stentstreben..  Eine vollständige Adaptation des Stentretrievers an die Gefäßwand ermöglicht eine effektive Thrombektomie mit geringer Embolierate, ist jedoch mit einer höheren notwendigen Retraktionskraft und damit potentiell höheren Gefahr einer Endothelverletzung verbunden. Veränderungen des Stentdesigns in den Prototypen mit Verminderung der Stärke der Stentstreben führen zu einer geringeren Retraktionskraft, beeinträchtigten jedoch nicht die Rekanalisierungs- und Embolierate..   · Die vollständige Adaptation des Stentretrievers an die Gefäßwand ermöglicht eine effektive Thrombektomie. · Diese ist mit einer höheren Retraktionskraft und möglicherweise Gefahr der Endothelverletzung verbunden. · Durch Verringerung der Strebendicke wird die Rekanalisations- und Embolierate nicht beeinträchtigt. · Die Retraktionskraft kann hierdurch vermindert werden.

Topics: Alloys; Brain Infarction; Device Removal; Endovascular Procedures; Equipment Design; Humans; In Vitro Techniques; Intracranial Embolism; Models, Cardiovascular; Postoperative Complications; Proof of Concept Study; Stents; Stroke; Thrombectomy

A high proportion of patients with stroke do not qualify for repetitive transcranial magnetic stimulation (rTMS) clinical studies due to the presence of metallic stents. The ultimate concern is that any metal could become heated due to eddy currents. However, to date, no clinical safety data are available regarding the risk of metallic stents heating with rTMS.. We tested the safety of common rTMS protocols (1 Hz and 10 Hz) with stents used commonly in stroke, nitinol and elgiloy. In our method, stents were tested in gelled saline at 2 different locations: at the center and at the lobe of the coil. In addition, at each location, stent heating was evaluated in 3 different orientations: parallel to the long axis of coil, parallel to the short axis of the coil, and perpendicular to the plane of the coil.. We found that stents did not heat to more than 1°C with either 1 Hz rTMS or 10 Hz rTMS in any configuration or orientation. Heating in general was greater at the lobe when the stent was oriented perpendicularly.. Our study represents a new method for ex vivo quantification of stent heating. We have found that heating of stents was well below the Food and Drug Administration standards of 2°C. Thus, our study paves the way for in vivo testing of rTMS (≤10 Hz) in the presence of implanted magnetic resonance imaging-compatible stents in animal studies. When planning human safety studies though, geometry, orientation, and location relative to the coil would be important to consider as well.

Topics: Alloys; Chromium Alloys; Cobalt; Endovascular Procedures; Equipment Failure Analysis; Heating; Humans; Materials Testing; Prosthesis Design; Prosthesis Failure; Risk Assessment; Stents; Stroke; Transcranial Direct Current Stimulation

In this study, a polymeric membrane has been designed and developed for carotid stents to prevent detachment of emboli from the arterial wall and subsequent stroke, while maintaining side-branch flow. Prototypes of different geometrical design parameters have been fabricated and their performance has been evaluated in vitro under physiological pulsatile flow condition in a life-size silicone anastomotic model of carotid artery bifurcation. These evaluations include both quantitative and qualitative experimental (in vitro) assessments of emboli prevention capability, side-branch flow preservation, and flow visualization. The covered stents with the novel membrane demonstrated significantly higher emboli prevention capability than the corresponding bare nitinol stent as well as some earlier related designs, while preserving more than 93% of the original flow of the external carotid artery (ECA). Flow in the ECA through these covered stents was uniform without evidence of undesirable flow recirculation or retrograde flow that might predispose the vessel wall to intimal thickening and atherosclerotic plaque formation. This study demonstrated the potential of these novel covered stent designs for the treatment of carotid atherosclerotic stenosis and prevention of late embolic stroke. However, further in vivo investigations of biological effects and mechanical performance of this covered stent design (e.g., its thrombogenicity potential and biocompatibility) are warranted.

Topics: Alloys; Blood Flow Velocity; Carotid Arteries; Carotid Stenosis; Coated Materials, Biocompatible; Humans; Membranes, Artificial; Models, Anatomic; Models, Cardiovascular; Polymers; Prosthesis Design; Pulsatile Flow; Stents; Stroke; Thromboembolism

Several randomized trials of patients with carotid stenosis show increased adverse neurological events with stenting versus endarterectomy in the 30-day post-procedure. This study examines the incidence of new ischaemic lesions in patients treated in our centre using the new Roadsaver stent.. Between September 2015 and January 2016, 23 consecutive patients (age 74.3 ± 7.3 years, 17.4 % female) underwent carotid artery stenting with the Roadsaver stent, a nitinol double-layer micromesh device. A distal protection device was used in all cases. Diffusion-weighted magnetic resonance imaging was performed 24 h before, and 24 h and 30 days after the procedure. The 24-h post-procedure imaging showed 15 new ipsilateral ischaemic lesions in 7 (30.4 %) patients: median volume 0.076 cm. Protected stenting with micromesh Roadsaver stent showed good safety and efficacy in the treatment of carotid stenosis, with a low incidence of delayed embolic events and new ipsilateral ischaemic brain lesions. These preliminary results are encouraging, but need to be confirmed with larger populations.

Topics: Aged; Aged, 80 and over; Alloys; Brain Ischemia; Carotid Stenosis; Diffusion Magnetic Resonance Imaging; Equipment Design; Female; Humans; Incidence; Male; Middle Aged; Prospective Studies; Recurrence; Stents; Stroke; Treatment Outcome

Stent-assisted embolization (SAE) has broadened the scope of endovascular cerebral aneurysm treatment. The risks associated with stent selection and configuration are poorly defined. In this study, the authors aimed to characterize the risk factors that contribute to complications in SAE of intracranial aneurysms.. Over a 10-year period, a single surgeon treated 486 aneurysms with SAE in which open-cell Neuroform or closed-cell Enterprise stents were used. Single stents were used in 386 cases, overlapping stents were deployed in 80 cases, and Y-configuration stents were used in the remaining 20 cases. All neurological complications, which included transient deficits, were analyzed; disabling strokes and death were considered major complications. The chi-square test and multivariate logistic regression were used to evaluate the influence of aneurysm size and morphology, aneurysm location, stent selection, and stent configuration on complication rates.. There were 7 deaths (1.4%), 9 major strokes (1.9%), and 18 minor neurological complications (3.7%). For all complications, multivariate analysis revealed that large aneurysm size (10-25 mm; p = 0.01), giant aneurysm size (> 25 mm; p = 0.04), fusiform aneurysm morphology (p = 0.03), and using a Y-configuration stent (p = 0.048) were independent risk factors. For the major complications, independent risk factors included an aneurysm in the posterior circulation (p = 0.02), using an overlapping stent configuration (p = 0.03), and using a Y-configuration stent (p < 0.01).. In this series, SAE for cerebral aneurysm treatment carried an acceptable complication rate. With continued innovations in techniques and devices and with increased experience, the complication rates associated with SAE may be even lower in the future.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Blood Vessel Prosthesis; Embolization, Therapeutic; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Risk Factors; Stents; Stroke; Treatment Outcome; Young Adult

Acute ischemic stroke (AIS) is the third leading cause of death. Arterial stenosis is a common cause of stroke, with a high risk of recurrent stroke. Treatment guidelines for AIS and transient ischemic attack (TIA) are still under debate. Treatment guidelines for progressive stroke or crescendo TIAs do not exist. Percutaneous transluminal angioplasty and stenting (PTAS) is an increasingly attractive treatment option, whose efficacy is yet to be proven. However, stent placement poses both short- and long-term risks such as immediate ischemic events, in-stent stenosis, and stent breakage. Thus the choice of stent type is critical. We report our experience with the LEO + (Balt Extrusion, Montmorency, France) nitinol flexible self-expanding stent for the treatment of progressive cerebrovascular accident or crescendo TIAs.. Twelve patients, presenting with a clinical picture of a crescendo TIA or progressive stroke in evolution not halted by optimal medical care, were treated. Patients had a corresponding major cerebral arterial narrowing and evidence of cerebral infarction on imaging. Patients were followed clinically and radiographically.. Twelve patients 17 to 80 years of age were treated during the study period (20 months). Sixteen nitinol flexible self-expandable stents (LEO +) were placed. All patients showed moderate to substantial improvement in neurologic functions after the procedure.. PTAS should be considered a treatment option in case of progressive stroke or crescendo TIAs coupled with appropriate anatomical findings. This may allow for a substantial improvement in functional and neurologic status.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Alloys; Female; Humans; Ischemic Attack, Transient; Male; Middle Aged; Neurosurgical Procedures; Stents; Stroke; Treatment Outcome; Young Adult

Transcatheter aortic valve implantation is a widely performed procedure for treatment of symptomatic severe aortic stenosis. According to the current literature, major stroke has been reported as occurring in 3-6% of patients during the first 30 days following valve implantation. Several pathological mechanisms may be involved in the development of periprocedural ischaemic stroke with the majority being due to thromboembolism and atheroembolism. One approach to reduce the incidence of procedural cerebral thromboembolic events is the use of cerebral protection devices, either deflecting (Embrella, TriGuard) or capturing (Claret, Embol-X) embolic material. We decided to review the current evidence on this important issue focusing on the four cerebral protection devices currently available.

Topics: Alloys; Aortic Valve; Aortic Valve Stenosis; Cardiac Catheterization; Contraindications; Equipment and Supplies; Equipment Design; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Incidence; Risk Factors; Stroke; Thromboembolism; Treatment Outcome

Atrial septal defect (ASD) was closed percutaneously in an 18-year-old boy with a 27 mm nitinol wire mesh occluder according to standard procedures. Three hours after the procedure, he presented anxiety attacks, aggression, a vacant stare and a verbal/speaking disorder. Small ischaemic stroke localised in the right temporal/parietal region of the central nervous system was confirmed by computed tomography examination. Activated partial thromboplastin time was then 54 s despite continuous heparin infusion. Heparin dose was increased and symptomatic treatment was introduced (mannitol, furosemide, propofol, haloperidol). The next day, all symptoms disappeared. He remained in good clinical condition, without neurological disorders 1.5 months after the procedure. Complications related to transcatheter ASD closure still exist despite the fulfillment of standard procedural criteria. Frequent coagulogical examinations during and after the procedure are necessary. Close observation and follow-up of treated patients is mandatory.

Topics: Adolescent; Aggression; Alloys; Anxiety; Catheter Ablation; Heart Septal Defects, Atrial; Humans; Male; Septal Occluder Device; Stroke; Tomography, X-Ray Computed

Intracranial atherosclerosis may be the underlying pathology in up to 15% of ischemic strokes, but may account for about 40% of strokes in some populations. After an ischemic event determined by intracranial atherosclerosis, patients have a 12% annual risk of stroke recurrence, mostly during the first year.. To evaluate procedural safety, clinical outcome and restenosis rate of Wingspan stent placement.. Twenty-one caucasoid patients were enrolled. Target patients were affected by high-grade, symptomatic, intracranial atherosclerotic lesions, were on antithrombotic therapy and at high stroke risk. All patients were treated with the Wingspan stent system.. Technical success resulted 100%, with all target lesions being reduced to <50%. No stroke or death were observed at 30. The mean percent of stenosis was reduced from a middle value of 84% to a middle value of 17% after stent placement. Medium follow-up was 19.5months (range 6-36months). No stroke or death occurred in any patient. None of the patients presented a <50% stent patency rate at follow-up.. The short-term results and follow up analysis provide evidence demonstrating the safety of the Wingspan system when used in high-risk patient population. Due to concerns regarding long-term stent patency and ischemic events occurrence emerged from clinical trials such as the SAMMPRIS, intracranial angioplasty and stent with the Wingspan system should be considered only for high risk patients in which it may be considered the only viable therapeutic option.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty; Brain Ischemia; Cerebral Angiography; Constriction, Pathologic; Endpoint Determination; Female; Fibrinolytic Agents; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Magnetic Resonance Angiography; Male; Middle Aged; Plaque, Atherosclerotic; Platelet Aggregation Inhibitors; Recurrence; Stents; Stroke; Survival Rate; Tomography, X-Ray Computed; Treatment Outcome

Carotid artery stenting (CAS) has grown as a possible alternative for the treatment of extracranial cerebrovascular disease in the past decade. A preexisting contralateral carotid artery occlusion has been described as a risk factor for inferior outcomes after carotid endarterectomy, but its impact on CAS outcomes is less understood.. A retrospective review of 417 CAS procedures performed between May 2001 and July 2010 at a single center using self-expanding nitinol stents and mechanical embolic protection devices was conducted. Patients were divided into two groups, those with a preexisting contralateral carotid occlusion (group A, n = 39) versus those without a contralateral occlusion (group B, n = 378). Patient demographics and comorbidities as well as 30-day and late death, stroke, and myocardial infarction (MI) rates were analyzed. Mean follow-up was 4 years (range: 0-9.4 years).. Overall, mean age of the 314 men and 103 women was 70.5 years. In group A, there were two (5.1%) octogenarians and nine patients (23.1%) with symptomatic disease as compared with group B with 53 (14%) octogenarians and 121 (32%) patients with symptomatic disease. The overall 30-day death, stroke, and MI rates were 0.5%, 1.9%, and 0.7%, respectively. When comparing group A with group B, these results were not significantly different: death (0% vs. 0.5%), stroke (2.6% vs. 1.9%), and MI (0% vs. 0.8%). Long-term outcomes for groups A and B were also not significantly different: death (25.6% vs. 22.2%), stroke (5.3% vs. 3.4%), and MI (15.4% vs. 14%) (p = nonsignificant).. A preexisting contralateral carotid artery occlusion does not seem to adversely impact CAS outcomes.

Topics: Aged; Alloys; Angiography; Blood Vessel Prosthesis Implantation; Carotid Stenosis; Female; Follow-Up Studies; Humans; Male; Neural Tube Defects; Postoperative Complications; Retrospective Studies; Risk Factors; Stents; Stroke; Survival Rate; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; United States

In most patients with atrial fibrillation (AF) and stroke, there is thrombotic embolization from the left atrial appendage (LAA). Percutaneous closure of the LAA is a novel alternative for the treatment of patients with AF at a high risk of stroke, in whom long-term anticoagulation therapy is not possible or not desired. This study details the initial experience with the Amplatzer Cardiac Plug (ACP) in humans.. Investigator-initiated retrospective preregistry data collection to evaluate procedural feasibility and safety up to 24 hr after implantation of the ACP, a nitinol device designed for percutaneous trans-septal implantation in LAA of patients with paroxysmal, permanent, or persistent AF.. In 137 of 143 patients, LAA occlusion was attempted, and successfully performed in 132 (96%). There were serious complications in 10 (7.0%) patients (three patients with ischemic stroke; two patients experienced device embolization, both percutaneously recaptured; and five patients with clinically significant pericardial effusions). Minor complications were insignificant pericardial effusions in four, transient myocardial ischemia in two, and loss of the implant in the venous system in one patient.. The implantation of the ACP device is a feasible method for percutaneous occlusion of the LAA.

Topics: Aged; Aged, 80 and over; Alloys; Anticoagulants; Atrial Appendage; Atrial Fibrillation; Cardiac Catheterization; Europe; Feasibility Studies; Female; Humans; Male; Middle Aged; Prosthesis Design; Retrospective Studies; Septal Occluder Device; Stroke; Time Factors; Treatment Outcome

Thoracic endovascular aortic repair is increasingly becoming the standard treatment of many thoracic aortic pathologies. New reliable and accurate stent grafts are emerging to widen the endovascular treatment options. We report the results of RELAY (Bolton Medical, Barcelona, Spain) in the large RELAY Endovascular Registry for Thoracic Disease (RESTORE) European registry.. RESTORE is a multicenter, prospective European registry involving 22 centers in seven European countries. The RELAY device is composed of a stent graft (self-expanding nitinol stents and a polyester vascular graft) and a delivery device specifically designed for the thoracic aorta. Included were acute and elective patients presenting with a variety of pathologies (aneurysms, dissections, ulcerations, intramural hematomas, pseudoaneurysms) and lesions in different aortic and anatomic locations (ascending, arch, descending and thoracoabdominal).. The registry enrolled 304 patients from April 2005 to January 2009. All-cause mortality at 30 days was 7.2%. Freedom from all cause mortality and freedom from device- and procedure-related mortality at 2 years were 78.5% and 95.9%, respectively. An average of 1.26 graft components were used per patient, with a technical success of 97.7% irrespective of the etiology. Early endoleak rate was 4.6%. Perioperatively, stroke and paraplegia were registered in 1.6% and 2.0%, respectively.. The results of RESTORE support the safety of thoracic endovascular aortic repair with the RELAY stent graft, even in acute and complicated situations. The device was highly efficient in angulated aortic anatomies, with acceptable mortality and a low rate of neurologic complications.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Alloys; Aorta, Thoracic; Aortic Diseases; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endoleak; Endovascular Procedures; Europe; Female; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Paraplegia; Polyesters; Prospective Studies; Prosthesis Design; Registries; Risk Assessment; Stents; Stroke; Time Factors; Treatment Outcome; Young Adult

Topics: Alloys; Anticoagulants; Atrial Appendage; Atrial Fibrillation; Cardiac Catheterization; Evidence-Based Medicine; Humans; Prosthesis Design; Septal Occluder Device; Stroke; Time Factors; Treatment Outcome

Topics: Alloys; Carotid Stenosis; Equipment Design; Humans; Polytetrafluoroethylene; Stents; Stroke; Treatment Outcome

Atrial fibrillation is a very common heart arrhythmia, associated with a five-fold increase in the risk of embolic strokes. Treatment strategies encompass palliative drugs or surgical procedures all of which can restore sinus rhythm. Unfortunately, atria often fail to recover their mechanical function and patients therefore require lifelong anticoagulation therapy. A motorless volume displacing device (Atripump) based on artificial muscle technology, positioned on the external surface of atrium could avoid the need of oral anticoagulation and its haemorrhagic complications. An animal study was conducted in order to assess the haemodynamic effects that such a pump could provide.. Atripump is a dome-shape siliconecoated nitinol actuator sewn on the external surface of the atrium. It is driven by a pacemaker-like control unit. Five non-anticoagulated sheep were selected for this experiment. The right atrium was surgically exposed, the device sutured and connected. Haemodynamic parameters and intracardiac ultrasound (ICUS) data were recorded in each animal and under three conditions; baseline; atrial fibrillation (AF); atripump assisted AF (aaAF).. In two animals, after 20 min of AF, small thrombi appeared in the right atrial appendix and were washed out once the pump was turned on. Assistance also enhanced atrial ejection fraction. 31% baseline; 5% during AF; 20% under aaAF. Right atrial systolic surfaces (cm2) were; 5.2 +/- 0.3 baseline; 6.2 +/- 0.1 AF; 5.4 +/- 0.3 aaAF.. This compact and reliable pump seems to restore the atrial "kick" and prevents embolic events. It could avoid long-term anticoagulation therapy and open new hopes in the care of end-stage heart failure.

Topics: Alloys; Animals; Anticoagulants; Atrial Fibrillation; Atrial Function, Right; Equipment Design; Heart-Assist Devices; Materials Testing; Sheep; Stroke; Thromboembolism

The aim of this study was to compare the clinical and ultrasound outcome of carotid artery stenting at 2-year follow-up in patients treated with open-cell nitinol stents versus patients treated with closed cell stainless steel stents.. This was a non-randomized, retrospective study including 123 patients in whom 132 carotid stent-procedures were performed. Nine patients were treated bilaterally. All patients presented with severe asymptomatic (80%) or symptomatic (>70%) carotid artery stenosis and were treated by carotid angioplasty and stent placement with or without filter embolic protection system. Follow-up consisted of physical evaluation at 1, 6, 12 and 24 months and assessment of the stent patency by ultrasound examination at 6, 12 and 24 months after the stent procedure.. In 72 procedures a closed cell stainless steel stent was implanted, in the remaining 60 procedures an open cell nitinol stent was placed. In 8 patients with a stainless steel stent (11%) and in 6 patients with a nitinol stent (10%) a stroke occurred during the follow-up period (P=0.79). Ultrasound examination revealed an in-stent restenosis of 50% to 80% in the stainless steel group (N.=9, 15%) and in the nitinol group (N.=10, 17%) (P=0.7).. At 2-year follow-up after carotid artery stenting, there is no difference in clinical outcome or in stent patency among patients treated with open versus closed cell design stents. Subsequently the type of carotid stent design does not seem to impact the overall midterm outcome after carotid artery stenting.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty; Carotid Stenosis; Female; Humans; Kaplan-Meier Estimate; Male; Prosthesis Design; Recurrence; Reoperation; Retrospective Studies; Risk Assessment; Severity of Illness Index; Stainless Steel; Stents; Stroke; Time Factors; Treatment Outcome; Ultrasonography

In more than 90% of patients with atrial fibrillation (AF), stroke is due to thrombotic embolization from the left atrial appendage (LAA). Transcatheter occlusion with percutaneous left atrial appendage transcatheter occlusion (PLAATO), a self-expanding, membrane- covered spherical nitinol cage, is feasible and an alternative to anticoagulation therapy.. This was a single-center prospective registry study for verification of stroke risk reduction in patients with AF 2 years after PLAATO.. Seventy-three patients with AF (permanent 65, paroxysmal 8) in whom anticoagulation therapy was contraindicated or rejected underwent transcatheter LAA occlusion with PLAATO. One patient died periprocedurally due to implant embolization, and 1 patient underwent open-heart surgery because of implant instability. The remaining 71 patients were followed for 24 months. In 52 patients a stable anchoring of the PLAATO device without migration or dislocation was documented by transesophageal echocardiography (TEE). No thrombotic deposition was found on the LA luminal surface of the device. Statistically, in our patient cohort, 7 strokes would have been expected without any treatment within 24 months. In fact, no strokes were reported. Ten out of 71 patients died during follow up: 6 in our hospital and 4 at home. None of them died from a stroke.. Ninety-seven percent of AF patients were successfully treated with PLAATO. After mechanical LAA occlusion, the 2-year risk of stroke in AF patients is markedly reduced. Therefore, this therapeutic concept is a clear alternative for patients with AF and contraindications for oral anticoagulation.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Anticoagulants; Atrial Fibrillation; Cardiac Catheterization; Contraindications; Female; Follow-Up Studies; Humans; Male; Middle Aged; Prospective Studies; Prostheses and Implants; Registries; Retrospective Studies; Risk Factors; Stroke; Thromboembolism; Treatment Outcome

Although extracranial carotid dissection with stroke is common, intracranial dissection with stroke is rare. Stenting has been used to treat extracranial carotid dissections. Intracranially, however, it is only recently that stents have become a feasible option for this disease. We present a case of a spontaneous intracranial CAD with progressive symptoms despite medical management treated with a self-expanding intracranial micronitinol stent.. A 47-year-old, right-handed woman presented to the emergency department after noticing left-sided face and arm weakness and numbness, along with slurred speech. The patient was started on aspirin 325 mg/d orally and lovenox 40 mg/d subcutaneously. On hospital day 2, the patient was noted to have repeated episodes of weakness and numbness on the left side and MRI evidence of a new stroke. A diagnostic cerebral angiogram from a selective right internal carotid injection revealed a flow-limiting stenosis secondary to a dissection of the supraclinoid internal carotid artery with severe flow limitation to the hemisphere. Endovascular management was decided on, and a Neuroform stent measuring 4.5 x 20 mm (Boston Scientific Corporation, Natick, Mass) was deployed across the dissection with significant improvement of flow to that hemisphere on the poststent angiogram.. This case illustrates the successful off-label use of a self-expanding intracranial nitinol stent to treat a symptomatic intracranial internal CAD in the setting of failure of traditional medical management. This is a promising application of novel endovascular technology.

Topics: Alloys; Anticoagulants; Brain; Brain Ischemia; Carotid Artery, Internal; Carotid Artery, Internal, Dissection; Cerebral Angiography; Female; Humans; Magnetic Resonance Angiography; Magnetic Resonance Imaging; Middle Aged; Platelet Aggregation Inhibitors; Stents; Stroke; Treatment Outcome; Vascular Surgical Procedures

To report the results from a prospective multicenter registry evaluating the safety and performance of a new hybrid stent specifically engineered for carotid indications.. Between October 18, 2006, and March 28, 2007, 124 patients (88 men; mean age 71.8+/-7.3 years, range 52-87) underwent Cristallo Ideale stent implantation at 4 expert sites in Italy and Germany. Eligibility criteria included >60% symptomatic and >80% asymptomatic carotid stenosis. Different cerebral protection devices were utilized (proximal protection and distal filters). The primary endpoint was the rate of 30-day major adverse neurological events, defined as major and minor stroke and neurological death by independent neurological assessment. All adverse events were adjudicated by an independent clinical event committee.. Stent deployment was completed successfully in all the cases without documented technical failure. There were no neurological events during the procedures. Thirty-day follow-up was available for 119 (96.0%) patients [2 (1.6%) were lost to follow-up and 3 (2.4%) died from non-neurological causes unrelated to the device or procedure]. There were no major adverse neurological events within 30 days, but 2 (1.6%) device-/procedure-related transient ischemic attacks were reported (both resolved completely in <24 hours). Four (3.2%) other non-neurological events (anemia requiring transfusion, worsening of pre-existing chronic renal failure, acute access site thrombosis, and monocular vision disturbance) were reported in the study period.. The Cristallo Ideale carotid stent is safe and effective in the periprocedural period. Its newly designed hybrid structure seems to support the rationale of combining adequate plaque scaffolding with high vessel adaptability.

Topics: Aged; Aged, 80 and over; Alloys; Carotid Stenosis; Female; Humans; Male; Middle Aged; Prospective Studies; Prosthesis Design; Registries; Safety; Stents; Stroke; Treatment Outcome

To assess the appearance of carotid artery stents at 3.0 Tesla contrast enhanced magnetic resonance angiography (CE-MRA) as compared with 1.5 Tesla.. 19 stents (GUIDANT Acculink, GUIDANT Dynalink, BOSTON SCIENTIFIC SMART Neuroform, GUIDANT Omnilink, EV3 Protege, BOSTON SCIENTIFIC Carotid Wallstent, ABBOTT Xact) of different materials (nitinol, stainless steal, cobalt alloy) and different sizes (4.0 mm-10.0 mm) were investigated regarding their appearance on CE-MRA at 3.0 Tesla and at 1.5 Tesla. For each stent artificial lumen narrowing (ALN) was calculated based on a pixel-by-pixel profile of the contrast-to-noise-ratio giving an objective indicator for the size of the evaluable stent diameter.. Only in two stents (Omnilink 7.0 mm, Omnilink 10.0 mm) was ALN higher at 3.0 Tesla relative to 1.5 Tesla. In all other stents ALN at 3.0 Tesla was the same or even lower as compared with 1.5 Tesla. In contrast to the ferromagnetic stents where ALN was typically higher than 85%, in most of the nitinol stents (Acculink, Dynalink, Neuroform, Protege) ALN was below 35%. In the Xact stents ALN was generally 100% at 1.5 Tesla and ranged between 31.8% and 100% at 3.0 Tesla.. CE-MRA after carotid artery stenting is considerably impaired by ALN both at 1.5 Tesla and at 3.0 Tesla. Nevertheless, CE-MRA is well suited for the examination of carotid artery stents made of nitinol at both field strengths. Stent manufacturers should be aware of potential artifacts caused by their stents during noninvasive diagnostic methods such as CE-MRA.

Topics: Alloys; Artifacts; Carotid Arteries; Cobalt; Contrast Media; Humans; In Vitro Techniques; Magnetic Resonance Angiography; Phantoms, Imaging; Stainless Steel; Stents; Stroke

To report the complications, rescue procedures, and consequences related to the use of an embolus protection filter during carotid artery stenting (CAS).. A retrospective review was undertaken of 72 patients (58 men; mean age 70.0+/-8.2 years, range 56-87) with extracranial atherosclerotic carotid stenosis who underwent 77 CAS procedures under filter protection. Filter-related events and rescue procedures according to each procedural step were retrospectively evaluated on CAS angiograms. In addition, neurological events and outcomes were also assessed.. CAS using a filter was successful in 99% of cases, and the overall rate of minor stroke (n=1), major stroke (0), or mortality (n=1) was 2.6% at 30 days. Filter placement was successful in all cases. However, arterial tortuosity made it difficult for a filter to pass through the stenosis in 1 case; this was overcome with an additional supportive wire (0.018-inch). Filter-related events were flow impairment in 6 (7.8%), filter wedging in the catheter tip in 4 (5.2%), vasospasm >50% narrowing in 7 (9.1%), filling defects within the filter membrane in 5 (6.5%), retrieval failure with the provided retriever in 3 (3.9%), and insecure retrieval without filter collapse in 2 (2.6%). Flow impairment caused drowsy mentality and impaired verbal response in 4, which resolved after prompt filter retrieval. All the cases of filter wedging were resolved with a catheter pulled down into the stented segment to separate the filter element from the catheter tip. Significant vasospasm and filling defects were spontaneously resolved in all cases after filter retrieval. Inability to pass a retriever catheter through a stent was overcome with curved 5-F catheter manipulation in all 3 cases.. The use of a filter during CAS may induce various angiographic or technical events at each step. For a severely stenotic and tortuous carotid lesion with difficult access, a filter may become trapped or irretrievable during flow arrest. Physicians should be aware of the preventive and rescue maneuvers to counter filter-related events, perhaps even considering another type of protection mechanism or carotid endarterectomy.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Atherosclerosis; Blood Vessel Prosthesis Implantation; Carotid Stenosis; Endarterectomy, Carotid; Equipment Design; Equipment Failure; Female; Filtration; Humans; Intracranial Embolism; Male; Middle Aged; Radiography; Retrospective Studies; Risk Factors; Safety; Stents; Stroke; Treatment Outcome; Vascular Patency; Vasospasm, Intracranial

Anticoagulation with warfarin for atrial fibrillation is frequently difficult. A transcatheter method to exclude the left atrial appendage from the circulation could be an advantage for selected patients. Percutaneous left atrial appendage transcatheter occlusion is a catheter-based delivery of an occlusive nitinol cage to the neck of the left atrial appendage. The device obliterates the left atrial appendage, eliminating a major source of thromboembolism. Animal studies have confirmed device coverage with an endocardial layer within 6 months and distal atrial appendage fibrosis. A standard transseptal approach from the right femoral vein is used. Patients leave the hospital within 1 day. Six-month follow-up of European and US safety and efficacy trials has shown favorable outcomes in minimizing thromboembolic events and few complications related to placement or healing of the device. Further clinical studies will be needed to establish which patients will be best treated with this device.

Topics: Age Factors; Aged; Aged, 80 and over; Alloys; Animals; Atrial Appendage; Atrial Fibrillation; Disease Models, Animal; Dogs; Echocardiography, Transesophageal; Humans; Middle Aged; Patient Selection; Prostheses and Implants; Risk Factors; Stroke

Angioplasty and stenting are becoming increasingly accepted techniques for the treatment of carotid stenosis. However, the optimal stent for carotid intervention is not known.. We compared the short- and intermediate-term results of carotid stenting using either nitinol or stainless-steel self-expanding stents in 178 high surgical risk patients undergoing carotid stenting at our institution. Of these 178 patients, eighty-nine received stainless-steel stents and 89 received nitinol stents. The groups were similar with respect to age, gender, diabetes, hypertension, left ventricular function, and symptom status. There were more patients with contralateral carotid occlusion in the nitinol stent group. Independent neurological evaluation was performed in all patients pre- and post-carotid stenting.. At 6 months, there was a similar incidence of stroke (3.3% versus 2.2%) in the stainless-steel group and nitinol stent group, respectively. There was higher 6-month mortality noted in the stainless-steel stent group, but there were no neurological deaths in either group.. In a single-center patient cohort with similar baseline characteristics, patients receiving nitinol stents and stainless-steel stents had similar neurological outcomes.

Topics: Aged; Aged, 80 and over; Alloys; Carotid Artery, Common; Carotid Artery, External; Carotid Stenosis; Equipment Safety; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Incidence; Male; Middle Aged; Ohio; Postoperative Complications; Radiography; Stents; Stroke; Survival Analysis; Time Factors; Treatment Outcome

Topics: Alloys; Carotid Artery, Common; Carotid Artery, External; Carotid Stenosis; Equipment Safety; Graft Occlusion, Vascular; Humans; Postoperative Complications; Stents; Stroke; Treatment Outcome