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Severe Carotid Stenosis (severe + carotid_stenosis)
Selected AbstractsOphthalmic Artery Flow Direction on Color Flow Duplex Imaging Is Highly Specific for Severe Carotid StenosisJOURNAL OF NEUROIMAGING, Issue 1 2002Patrick S. Reynolds MD Background/Purpose. Collateral flow patterns are important risk factors for brain ischemia in the presence of internal carotid artery (ICA) stenosis or occlusion. Ophthalmic artery (OA) flow reversal, routinely studied by transcranial Doppler sonography, is an important marker for high-grade ICA stenosis or occlusion. The authors sought to define the value of assessing OA flow direction with color flow duplex ultrasonography (CDUS) in the setting of significant ICA disease. Methods. Of all patients having routine carotid ultrasound in the neurosonology laboratory between July 1995 and November 2000, 152 had both carotid and orbital (OA flow direction by reduced power orbital CDUS) examinations as well as angiographic confirmation of stenosis to which North American Symptomatic Carotid Endarterectomy Trial criteria could be applied. Degree of angiographic stenosis in these 152 patients (304 arteries) was correlated with OA flow direction. Results. Of 304 arteries, 101 had greater than 80% stenosis by angiogram. In 56 of these 101 arteries with high-grade stenosis or occlusion, the ipsilateral OA was reversed; however, OA flow direction was never reversed ipsilateral to arteries with less than 80% stenosis (sensitivity 55%, specificity 100%, negative predictive value 82%, and positive predictive value 100% for OA flow reversal as a marker of high-grade carotid lesions). Discussion/Conclusions. OA flow direction is easily studied with CDUS. Reversed OA flow direction is highly specific (100%) for severe ipsilateral ICA stenosis or occlusion, with excellent positive predictive value, moderate negative predictive value, and limited sensitivity. OA flow reversal is not only quite specific for severe ICA disease, which may be helpful if the carotid CDUS is difficult or inadequate, but may also provide additional hemodynamic insights (ie, the inadequacy of other collateral channels such as the anterior communicating artery). OA evaluation can provide important hemodynamic information and should be included as part of carotid CDUS if there is any evidence of ICA stenosis or occlusion. [source] Cerebral vasomotor reactivity of bilateral severe carotid stenosis: is stroke unavoidable?EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2006A. Y. Gur We evaluated the cerebral hemodynamic features of severe bilateral carotid stenosis by assessing and comparing cerebral vasomotor reactivity (VMR) in the middle cerebral (MCA) and vertebral arteries (VA) by transcranial Doppler and the Diamox (1 g acetazolamide i.v.) test. VMR was evaluated by recording the percentage differences in peak systolic blood flow velocity in each MCA and VA at baseline and by the Diamox test. Twenty-eight symptomatic (SCAS) and 31 asymptomatic (ACAS) patients with bilateral severe (>70%) internal carotid artery stenosis were studied. The mean MCA VMR% was 29 ± 26.9% in SCAS and 43.2 ± 26.8% in ACAS patients (P < 0.01). Their respective mean VA VMR% was 30.2 ± 36.5% and 39.6 ± 24.4% (P = NS). VMR% of the symptomatic MCA side in SCAS patients was significantly lower than the opposite side (20.5 ± 31.1% and 39.2 ± 37.9% respectively; P < 0.03). In contrast, the VA VMR% of both sides in SCAS patients remained similar (28.1 ± 39.3% and 34.6 ± 47.9% respectively; P = NS). VMR% of the MCA and VA in ACAS patients was also similar for both sides of bilateral carotid stenosis. The cerebral hemodynamic features differ between SCAS and ACAS patients with bilateral carotid occlusive disease in the anterior part of the circle of Willis. An independent cerebral vascular reserve capacity of the posterior circulation is proposed. [source] Cognitive performance following endarterectomy in asymptomatic severe carotid stenosisEUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2003J. Aharon-Peretz Cognition and the effects of carotid endarterectomy (CEA) were evaluated in 22 non-demented subjects with vascular risk factors (VRF) and asymptomatic severe carotid artery stenosis (ASCAS), 14 volunteers with VRF but without stenosis, and 24 healthy controls (HC) without VRF. Non-demented subjects with VRF, with or without carotid stenosis scored inferior to HC. It is concluded that carotid stenosis is not a primary cause of cognitive deterioration and CEA does not improve cognition in patients with ASCAS. [source] Prevalence and outcome of asymptomatic carotid stenosis: a population-based ultrasonographic studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2002P. P. Mineva The aims of this epidemiological population-based cohort study were to examine the prevalence and outcomes of asymptomatic carotid stenosis (ACS) detected by duplex scanning and its relations to other vascular risk factors. A total of 500 volunteers, 200 men and 300 women, without signs and symptoms of cerebrovascular disease, aged 50,79 years, were enrolled in the study. The prevalence of ACS of 50% or greater was 6.4%. Only severe carotid stenosis was detected in 0.4% of the subjects examined. Significant relationships between ACS and coronary heart disease (CHD) [odds ratio (OR)=8.00], peripheral arterial disease (PAD) (OR=3.66), cigarette smoking in men (OR=4.39) and obesity in women (OR=0.31) were found. The biennial incidence rate of cerebral ischaemic events was 9.4%. A progression of ACS was revealed in 14% and a regression in 6.25% of the subjects. The patients with progressing ACS to more than 70% diameter reduction reached the end-points. Follow-up with repeated duplex scans in patients with advancing ACS of 50% or greater, especially smokers with CHD and PAD, is recommended. [source] Cerebral emboli and paradoxical embolisation in dementia: a pilot studyINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 1 2005Nitin Purandare Abstract Background The causes of the common dementias remain unknown. Paradoxical embolisation of the cerebral circulation by venous thrombi passing through venous to arterial shunts (v-aCS) in the heart or pulmonary circulation is known to occur in cryptogenic stroke and post-operative confusion following hip replacement. Objectives To explore the role of paradoxical embolisation in dementia by investigating for cerebral emboli, venous to arterial circulation shunt (v-aCS) and carotid artery disease. Methods Forty-one patients with dementia (24 Alzheimer's AD and 17 vascular VaD) diagnosed using DSM-IV criteria and 16 controls underwent transcranial Doppler (TCD) detection of spontaneous cerebral emboli in both middle cerebral arteries. A v-aCS was detected by intravenous injection of an air/saline ultrasound contrast at rest and after provocation by coughing and Valsalva's manoeuvre. Carotid artery disease was assessed by duplex imaging. Results Cerebral emboli were detected in 11 (27.5%) dementia patients compared with one (7%) control (p,=,0.15) with emboli being most frequent in VaD (41%) compared to controls [OR (95% CI): 10.5 (1.1, 98.9), p,=,0.04]. A v-aCS was detected in 25 (61%) patients and seven (44%) controls (p,=,0.24). In dementia patients with cerebral emboli; v-aCS was detected in seven (64%) and moderate to severe carotid stenosis was present in three (30%). Conclusion Cerebral emboli and v-aCS may be more frequent in patients with both VaD and AD than in controls, which suggest paradoxical embolisation as a potential mechanism for cerebral damage. This pilot study justifies a definitive case-control study. Copyright © 2004 John Wiley & Sons, Ltd. [source] Protected Carotid Stenting in High-Risk Patients: Results of the SpideRX Arm of the Carotid Revascularization with ev3 Arterial Technology Evolution TrialJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2010ROBERT D. SAFIAN M.D. Purpose:,A prospective nonrandomized multicenter registry of 160 patients with severe carotid stenosis and high-risk features for carotid endarterectomy was conducted during the 3-month period from March to May 2005. Methods:,Carotid artery stenting (CAS) was performed with the SpideRXÔ Embolic Protection System (ev3, Inc., Plymouth, MN, USA) as part of an investigational device exemption from the Food and Drug Administration. Results:,The primary end-point of major adverse cardiac and cerebrovascular events at 30 days after CAS was observed in nine patients (5.6%), including death in four patients (2.5%), nonfatal stroke in five patients (3.1%), and nonfatal myocardial infarction in one patient (0.6%). A secondary end-point of technical success (defined as successful deployment of all devices, filter retrieval, and final diameter stenosis <50%) was achieved in 156 of 160 patients (97.5%). The only independent predictor of death or stroke at 30 days was baseline stenosis severity (P < 0.05). Conclusion:,CAS with distal embolic protection using the SpideRXÔ Embolic Protection System is a reasonable alternative for revascularization of some high-risk patients with severe carotid stenosis. (J Interven Cardiol 2010;23:491,498) [source] Guidelines for patient selection and performance of carotid artery stentingANZ JOURNAL OF SURGERY, Issue 6 2010The Carotid Stenting Guidelines Committee Abstract Background:, The endovascular treatment of carotid atherosclerosis with carotid artery stenting (CAS) remains controversial. Carotid endarterectomy remains the benchmark in terms of procedural mortality and morbidity. At present, there are no consensus Australasian guidelines for the safe performance of CAS. Methods:, We applied a modified Delphi consensus method of iterative consultation between the College representatives on the Carotid Stenting Guidelines Committee (CSGC). Results:, Selection of patients suitable for CAS needs careful consideration of clinical and patho-anatomical criteria and cannot be directly extrapolated from clinical indicators for carotid endarterectomy (CEA). Randomized controlled trials (including pooled analyses of results) comparing CAS with CEA for treatment of symptomatic stenosis have demonstrated that CAS is more hazardous than CEA. On current evidence, the CGSC therefore recommends that CAS should not be performed in the majority of patients requiring carotid revascularisation. The evidence for CAS in patients with symptomatic severe carotid stenosis who are considered medically high risk is weak, and there is currently no evidence to support CAS as a treatment for asymptomatic carotid stenosis. The use of distal protection devices during CAS remains controversial with increased risk of clinically silent stroke. The knowledge requirements for the safe performance of CAS include an understanding of the evidence base from randomized controlled trials, carotid and aortic arch anatomy and pathology, clinical stroke syndromes, the differing treatment options for stroke and carotid atherosclerosis, and recognition and management of periprocedural complications. It is critical that all patients being considered for a carotid intervention have adequate pre-procedural neuro-imaging and an independent, standardized neurological assessment before and after the procedure. Maintenance of proficiency in CAS requires active involvement in surgical/endovascular audit and continuing medical education programs. These standards should apply in the public and private health care settings. Conclusion:, These guidelines represent the consensus of an inter-collegiate committee in order to direct appropriate patient selection and the range of cognitive and technical requirements to perform CAS. Advances in endovascular technologies and the results of randomized controlled trials will guide future revisions of these guidelines. [source] Feasibility and safety of transbrachial approach for patients with severe carotid artery stenosis undergoing stentingCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2006Chiung-Jen Wu MD Abstract Although sporadic successful cases using the transradial approach (TRA) for carotid stenting have been reported, the safety and feasibility of carotid stenting using either TRA or a transbrachial approach (TBA) have not been fully investigated. Recently, we have developed a safe and feasible method of TRA for cerebrovascular angiographic studies. This study investigated whether a TBA approach using a 7-French (F) Kimny guiding catheter for carotid stenting is safe and feasible for patients with severe carotid stenosis. Thirteen patients were enrolled into this study (age range, 63,78 years). Seven of these 13 patients had severe peripheral vascular disease. A retrograde-engagement technique, involving looping 6-F Kimny guiding catheter, was utilized for carotid angiographic study. For carotid stenting, the 6-F Kimny guiding catheter was replaced with a 7-F Kimny guiding catheter, and the procedure was performed as the follows. First, an extra-support wire was inserted into the middle portion of external carotid artery (ECA). Second, a 0.035-inch Teflon wire was advanced into the common carotid artery. Then, the 6-F guiding catheter was exchanged for a 7-F Kimny guiding catheter. Third, if the first and second steps did not provide adequate support for exchanging the guiding catheter, a PercuSurge GuardWireÔ was inserted into the ECA, followed by distal balloon inflation for an anchoring support. FilterWire EXÔ was used in 9 patients and PercuSurge GuardWire in 4 patients to protect from distal embolization during the procedure. The procedure was successful in all patients. No neurological or vascular bleeding complications were observed and all patients were discharged uneventfully. The TBA for carotid stenting was safe and effective, providing a last resort for patients unsuited to femoral arterial access and surgical intervention. © 2006 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 trialCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2004Robert 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] | ||||||||||||||||||||||