Local extension of HMGB1 in atherosclerotic lesions of human main cerebral and carotid arteries.

PubMed

Umahara, T; Uchihara, T; Koyama, S; Hashimoto, T; Akimoto, J; Haraoka, J; Iwamoto, T

2014-02-01

High mobility group box 1 protein (HMGB1) is a non-histone chromosomal protein which is highly conserved, ubiquitous, and widely distributed. HMGB1 has multiple functions in the nucleus, including the maintenance of nucleosome structure, the regulation of gene transcription, and involvement in DNA recombination. HMBG1 is currently recognized to have a wide range of potential functions and pathological relevance. HMGB1 is released into the extracellular space from necrotic cells and from activated macrophages. HMGB1 binds to the receptor for advanced glycation end products, resulting in the induction of inflammatory cytokines, and to endothelial cell thrombomodulin. HMGB1 neutralization may also reduce the development of atherosclerosis and ameliorate brain infarction. We investigated the immunolocalization of HMGB1 in atherosclerotic lesions of human cerebral and carotid arteries using a specific antibody, and confirmed the detailed expression and cell type localization using double immunofluorolabeling. In the main cerebral arteries, this anti-HMGB1 antibody intensely immunolabeled both normal morphological vascular smooth muscle cells (VSMCs) within the tunica media and infiltrating VSMCs within the intima of thickened fibrous cap plaques. Endothelial cells were also positive for HMGB1. In carotid plaques, HMGB1-like immunoreactivity (IR) was intense in macrophages, although this IR decreased with increasing cell size. Medium-sized foam cells (50-150 μm) were the most intensely stained. This IR was also observed in the nuclei of foam cells and VSMCs. These findings may provide a basis for understanding the association of HMGB1 with atherosclerotic lesions of the cerebral and carotid arteries, and for constructing strategies to counteract atherosclerosis with anti-HMGB1 antibody.

Assessment of MMP-9, TIMP-1, and COX-2 in normal tissue and in advanced symptomatic and asymptomatic carotid plaques

PubMed Central

2011-01-01

Background Mature carotid plaques are complex structures, and their histological classification is challenging. The carotid plaques of asymptomatic and symptomatic patients could exhibit identical histological components. Objectives To investigate whether matrix metalloproteinase 9 (MMP-9), tissue inhibitor of MMP (TIMP), and cyclooxygenase-2 (COX-2) have different expression levels in advanced symptomatic carotid plaques, asymptomatic carotid plaques, and normal tissue. Methods Thirty patients admitted for carotid endarterectomy were selected. Each patient was assigned preoperatively to one of two groups: group I consisted of symptomatic patients (n = 16, 12 males, mean age 66.7 ± 6.8 years), and group II consisted of asymptomatic patients (n = 14, 8 males, mean age 67.6 ± 6.81 years). Nine normal carotid arteries were used as control. Tissue specimens were analyzed for fibromuscular, lipid and calcium contents. The expressions of MMP-9, TIMP-1 and COX-2 in each plaque were quantified. Results Fifty-eight percent of all carotid plaques were classified as Type VI according to the American Heart Association Committee on Vascular Lesions. The control carotid arteries all were classified as Type III. The median percentage of fibromuscular tissue was significantly greater in group II compared to group I (p < 0.05). The median percentage of lipid tissue had a tendency to be greater in group I than in group II (p = 0.057). The percentages of calcification were similar among the two groups. MMP-9 protein expression levels were significantly higher in group II and in the control group when compared with group I (p < 0.001). TIMP-1 expression levels were significantly higher in the control group and in group II when compared to group I, with statistical difference between control group and group I (p = 0.010). COX-2 expression levels did not differ among groups. There was no statistical correlation between MMP-9, COX-2, and TIMP-1 levels and fibrous tissue. Conclusions

Sympathoinhibition and hypotension in carotid sinus hypersensitivity

NASA Technical Reports Server (NTRS)

Smith, M. L.; Ellenbogen, K. A.; Eckberg, D. L.

1992-01-01

Carotid sinus reflex hypersensitivity is a known cause of syncope in humans. The condition is characterized by cardioinhibition and vasodepression, each to varying degrees. The extent and importance of sympathoinhibition has not been determined in patients with carotid sinus hypersensitivity. This study reports on the extent of sympathoinhibition measured directly directly during carotid massage with and without atrioventricular sequential pacing, in a patient with symptomatic carotid sinus reflex hypersensitivity. Carotid massage elicited asystole, hypotension and complete inhibition of muscle sympathetic nerve activity. Carotid massage during atrioventricular pacing produced similar sympathoinhibition, but with minimal hypotension. Therefore, sympathoinhibition did not contribute importantly to the hypotension during carotid massage in the supine position in this patient. Further investigations are required to elucidate the relation of sympathoinhibition to hypotension in patients with carotid sinus hypersensitivity in the upright position.

Carotid artery Doppler ultrasonography in retinal macroaneurysms.

PubMed

Thurairajan, G; Potamitis, T; Naylor, G; Gibson, J

1998-01-01

It is postulated that retinal arterial macroaneurysms (RAMs) occur at the site of incomplete embolic occlusion of a branch retinal artery. Embolic events of the retinal vessels are related to the state of the carotid artery tree and therefore Doppler ultrasonography of the carotid arteries in these patients is of particular interest. We have examined 13 patients with retinal artery macroaneurysms with carotid artery Doppler ultrasonography (CADU). Eight of these patients (61.5%) exhibited atheromatous plaques on the same side as the RAM with a moderate degree of arterial narrowing. Although our group of patients did not show advanced carotid artery disease, alterations of the arterial wall found at the level of the carotid artery were higher than expected in a similar hypertensive population. To our knowledge this is the first study of the carotid arterial tree in these patients. Our results support the theory that RAMs may be of embolic origin. Furthermore they demonstrate that CADU is a useful investigation in patients with RAMs.

High-risk carotid plaque: lessons learned from histopathology.

PubMed

Kolodgie, Frank D; Yahagi, Kazuyuki; Mori, Hiroyoshi; Romero, Maria E; Trout, Hugh H; Finn, Aloke V; Virmani, Renu

2017-03-01

The pathophysiology and natural history of atherosclerotic carotid disease is predicated on a more extensive knowledge of lesion progression gained in the studies conducted in the coronary arteries, and these will be reviewed. While the precise sequence of lesion progression leading to carotid plaque vulnerability and cerebrovascular events remain less well understood, specific early and more advanced progressive lesion morphologies associated with stroke risk have been characterized. Of late, there has been a conscious effort for stroke prevention in symptomatic and asymptomatic patients to move beyond luminal stenosis as the only guidance to predict future cerebrovascular events. Driving this strategy are recent advances in medical imaging modalities to assess carotid atherosclerosis vulnerability particularly involving molecular imaging, which is now positioned at the forefront to provide a more detailed and mechanistic assessment of stroke risk. As such, we will spotlight the pathology of high-risk carotid plaques in patients with symptomatic and asymptomatic carotid disease with further reference into more recent mechanistic insights involving a recognized macrophage-mediated inflammatory change, intraplaque neoangiogenesis/hemorrhage, hypoxia, and microcalcification, as potential morphologic indicators of stroke risk. Copyright © 2017 Elsevier Inc. All rights reserved.

Treatment of Carotid Artery Disease: Endarterectomy or Angioplasty?

PubMed Central

Marchidann, Adrian; Marshall, Randolph S.

2011-01-01

The management of carotid stenosis has enjoyed renewed interest in the neurological community in recent years due to the advent of endovascular approaches. In concert, progress in medical treatment of these patients has rekindled the debate regarding the best management of carotid stenosis overall, both for symptomatic and asymptomatic disease. For symptomatic carotid stenosis, the major decision required is choosing the type of intervention best suited for individual patients — carotid endarterectomy (CEA) versus carotid artery stenting (CAS). For patients with asymptomatic carotid stenosis, intensive medical management has evolved significantly over the past decade to decrease the risk of ischemic stroke to match surgical intervention under most circumstances. This review will examine the supporting evidence for each intervention, and discuss the recent advances in medical and endovascular therapy that provide the data for a new era in clinical decision making. PMID:20960240

Effects of acute hyperthermia on the carotid baroreflex control of heart rate in humans

NASA Astrophysics Data System (ADS)

Yamazaki, F.; Sagawa, S.; Torii, R.; Endo, Y.; Shiraki, K.

The purpose of this study was to examine the effect of hyperthermia on the carotid baroreceptor-cardiac reflexes in humans. Nine healthy males underwent acute hyperthermia (esophageal temperature 38.0° C) produced by hot water-perfused suits. Beat-to-beat heart rate (HR) responses were determined during positive and negative R-wave-triggered neck pressure steps from +40 to -65 mm Hg during normothermia and hyperthermia. The carotid baroreceptor-cardiac reflex sensitivity was evaluated from the maximum slope of the HR response to changes in carotid distending pressure. Buffering capacity of the HR response to carotid distending pressure was evaluated in % from a reference point calculated as (HR at 0 mm Hg neck pressure-minimum HR)/HR range ×100. An upward shift of the curve was evident in hyperthermia because HR increased from 57.7+/-2.4 beats/min in normothermia to 88.7+/-4.1 beats/min in hyperthermia (P<0.05) without changes in mean arterial pressure. The maximum slope of the curve in hyperthermia was similar to that in normothermia. The reference point was increased (P<0.05) during hyperthermia. These results suggest that the sensitivity of the carotid baroreflex of HR remains unchanged in hyperthermia. However, the capacity for tachycardia response to rapid onset of hypotension is reduced and the capacity for bradycardia response to sudden hypertension is increased during acute hyperthermia.

Hybrid microscopy of human carotid atheroma by means of optical-resolution optoacoustic and non-linear optical microscopy

NASA Astrophysics Data System (ADS)

Seeger, Markus; Karlas, Angelos; Soliman, Dominik; Pelisek, Jaroslav; Ntziachristos, Vasilis

2017-03-01

Carotid atheromatosis is causally related to stroke, a leading cause of disability and death. We present the analysis of a human carotid atheroma using a novel hybrid microscopy system that combines optical-resolution optoacoustic (photoacoustic) microscopy and several non-linear optical microscopy modalities (second and third harmonic generation, as well as, two-photon excitation fluorescence) to achieve a multimodal examination of the extracted tissue within the same imaging framework. Our system enables the label-free investigation of atheromatous human carotid tissue with a resolution of about 1 μm and allows for the congruent interrogation of plaque morphology and clinically relevant constituents such as red blood cells, collagen, and elastin. Our data reveal mutual interactions between blood embeddings and connective tissue within the atheroma, offering comprehensive insights into its stage of evolution and severity, and potentially facilitating the further development of diagnostic tools, as well as treatment strategies.

Carotid artery stenting: current and emerging options

PubMed Central

Morr, Simon; Lin, Ning; Siddiqui, Adnan H

2014-01-01

Carotid artery stenting technologies are rapidly evolving. Options for endovascular surgeons and interventionists who treat occlusive carotid disease continue to expand. We here present an update and overview of carotid stenting devices. Evidence supporting carotid stenting includes randomized controlled trials that compare endovascular stenting to open surgical endarterectomy. Carotid technologies addressed include the carotid stents themselves as well as adjunct neuroprotective devices. Aspects of stent technology include bare-metal versus covered stents, stent tapering, and free-cell area. Drug-eluting and cutting balloon indications are described. Embolization protection options and new direct carotid access strategies are reviewed. Adjunct technologies, such as intravascular ultrasound imaging and risk stratification algorithms, are discussed. Bare-metal and covered stents provide unique advantages and disadvantages. Stent tapering may allow for a more fitted contour to the caliber decrement between the common carotid and internal carotid arteries but also introduces new technical challenges. Studies regarding free-cell area are conflicting with respect to benefits and associated risk; clinical relevance of associated adverse effects associated with either type is unclear. Embolization protection strategies include distal filter protection and flow reversal. Though flow reversal was initially met with some skepticism, it has gained wider acceptance and may provide the advantage of not crossing the carotid lesion before protection is established. New direct carotid access techniques address difficult anatomy and incorporate sophisticated flow-reversal embolization protection techniques. Carotid stenting is a new and exciting field with rapidly advancing technologies. Embolization protection, low-risk deployment, and lesion assessment and stratification are active areas of research. Ample room remains for further innovations and developments. PMID:25349483

Recommendations for Management of Patients with Carotid Stenosis

PubMed Central

Lovrencic-Huzjan, Arijana; Rundek, Tatjana; Katsnelson, Michael

2012-01-01

Stroke is a one of the leading causes of morbidity and mortality in the world. Carotid atherosclerosis is recognized as an important factor in stroke pathophysiology and represents a key target in stroke prevention; multiple treatment modalities have been developed to battle this disease. Multiple randomized trials have shown the efficacy of carotid endarterectomy in secondary stroke prevention. Carotid stenting, a newer treatment option, presents a less invasive alternative to the surgical intervention on carotid arteries. Advances in medical therapy have also enabled further risk reduction in the overall incidence of stroke. Despite numerous trials and decades of clinical research, the optimal management of symptomatic and asymptomatic carotid disease remains controversial. We will attempt to highlight some of the pivotal trials already completed, discuss the current controversies and complexities in the treatment decision-making, and postulate on what likely lies ahead. This paper will highlight the complexities of decision-making optimal treatment recommendations for patients with symptomatic and asymptomatic carotid stenosis. PMID:22645702

12- and 15-lipoxygenases in human carotid atherosclerotic lesions: Associations with cerebrovascular symptoms

USDA-ARS?s Scientific Manuscript database

Lipoxygenase (ALOX) enzymes are implicated in both pro- and anti-atherogenic processes. The aim of this study was to investigate mRNA expression of 12- and 15-lipoxygenases (ALOX12, ALOX12B, ALOX15, ALOX15B) and the atypical ALOXE3 in human carotid atherosclerotic lesions, in relation to cerebrovasc...

Flow field and oscillatory shear stress in a tuning-fork-shaped model of the average human carotid bifurcation.

PubMed

Ding, Z; Wang, K; Li, J; Cong, X

2001-12-01

The oscillatory shear index (OSI) was developed based on the hypothesis that intimal hyperplasia was correlated with oscillatory shear stresses. However, the validity of the OSI was in question since the correlation between intimal thickness and the OSI at the side walls of the sinus in the Y-shaped model of the average human carotid bifurcation (Y-AHCB) was weak. The objectives of this paper are to examine whether the reason for the weak correlation lies in the deviation in geometry of Y-AHCB from real human carotid bifurcation, and whether this correlation is clearly improved in the tuning-fork-shaped model of the average human carotid bifurcation (TF-AHCB). The geometry of the TF-AHCB model was based on observation and statistical analysis of specimens from 74 cadavers. The flow fields in both models were studied and compared by using flow visualization methods under steady flow conditions and by using laser Doppler anemometer (LDA) under pulsatile flow conditions. The TF-shaped geometry leads to a more complex flow field than the Y-shaped geometry. This added complexity includes strengthened helical movements in the sinus, new flow separation zone, and directional changes in the secondary flow patterns. The results show that the OSI-values at the side walls of the sinus in the TF-shaped model were more than two times as large as those in the Y-shaped model. This study confirmed the stronger correlation between the OSI and intimal thickness in the tuning-fork geometry of human carotid bifurcation, and the TF-AHCB model is a significant improvement over the traditional Y-shaped model.

Treatment of symptomatic carotid stenosis: carotid stent placement versus endarterectomy.

PubMed

Alqadri, Syeda L; Qureshi, Adnan I

2013-08-01

The mainstay of treatment options for symptomatic carotid stenosis is focused around medical management, carotid endarterectomy, and carotid angioplasty and stent placement. The International Carotid Stenting Study (ICSS), also called Carotid and Vertebral Artery Transluminal Angioplasty Study 2 (CAVATAS 2), the Stent-Supported Percutaneous Angioplasty of the Carotid Artery Versus Endarterectomy (SPACE) trial, the Endarterectomy Versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial, the Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial, and the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST) were five major trials which compared carotid endarterectomy and carotid angioplasty and stent placement. We review the results of the trials and incorporation of the results into clinical decision making.

Carotid artery stiffness in patients with symptomatic carotid artery disease with contralateral asymptomatic carotid artery disease and in patients with bilateral asymptomatic carotid artery disease: a cine phase-contrast carotid MR study.

PubMed

Sadat, Umar; Usman, Ammara; Howarth, Simon P S; Tang, Tjun Y; Alam, Fahreyar; Graves, Martin J; Gillard, Jonathan H

2014-04-01

Atherosclerosis is a systemic inflammatory disease that may affect multiple arterial beds simultaneously. Vascular distensibility is increasingly used in the clinical assessment of patients with atherosclerotic disease. In this study, we assess distensibility of symptomatic atherosclerotic carotid artery and of contralateral asymptomatic side. We also investigate the distensibility of bilaterally asymptomatic atherosclerotic carotid arteries using cine phase-contrast carotid magnetic resonance (MR) imaging. Nineteen patients with bilateral carotid artery disease underwent cine phase-contrast carotid imaging on a 1.5 T MR system. Ten patients had ipsilateral symptomatic carotid artery disease and contralateral asymptomatic stenosis. Nine additional patients with bilateral asymptomatic carotid artery disease constituted historical control group. Cine phase-contrast MR imaging acquired at the common carotid artery, maximum luminal stenosis, and internal carotid artery was used to determine carotid distensibility bilaterally for carotid arteries in both patient groups. Symptomatic carotid arteries were found to be significantly less distensible (mean distensibility coefficient [DC] 35.4 ± 6.12 × 10(-3)/kPa) than the contralateral asymptomatic vessels (mean DC 54.4 ± 7.88 × 10(-3)/kPa, P = .03) at the level of the common carotid artery. A similar trend of high distensibility for asymptomatic side in the area of maximum stenosis and the internal carotid artery was seen, but it was not found to be statistically significant. Plaque burden was comparable between the 2 groups at all locations. DC was comparable for patients with bilateral asymptomatic carotid artery stenoses. Distensibility of bilaterally asymptomatic carotid arteries was greater than that of asymptomatic carotid artery contralateral to the symptomatic side. Symptomatic carotid artery is stiffer than the contralateral asymptomatic side, despite comparable plaque burden. Patients with bilateral

Evidence for Management of Carotid Artery Stenosis

PubMed Central

YOSHIDA, Kazumichi; MIYAMOTO, Susumu

2015-01-01

In this review, we presented the evidence concerning carotid artery stenosis treatment in symptomatic stenosis and asymptomatic stenosis separately, and discussed the future challenges. The validity of carotid endarterectomy (CEA) to treat moderate or greater degree of symptomatic carotid artery stenosis appears to be established. Due to the additional option of carotid artery stenting (CAS), it is necessary to comprehensively determine whether CEA or CAS is more appropriate for each individual patient. Moreover, since there are rapid advancements in devices for CAS and improvements in treatment outcomes, continual learning of the latest treatment method is essential. For asymptomatic stenosis, due to improvements in the outcomes with best medical treatment (BMT), it is essential to re-evaluate the use of invasive CEA/CAS. Continual verification of the latest randomized clinical trial that compares CEA, CAS, and BMT, and establishment of a diagnostic method that can accurately extract the group of patients who have the highest future risk of developing ischemia, are desired. PMID:25739437

Diagnostic yield of 90-kVp low-tube-voltage carotid and intracerebral CT-angiography: effects on radiation dose, image quality and diagnostic performance for the detection of carotid stenosis.

PubMed

Leithner, Doris; Wichmann, Julian L; Mahmoudi, Scherwin; Martin, Simon S; Albrecht, Moritz H; Vogl, Thomas J; Scholtz, Jan-Erik

2018-06-01

To investigate the impact of low-tube-voltage 90-kVp acquisition combined with advanced modeled iterative reconstruction algorithm (Admire) on radiation exposure, image quality, artifacts, and assessment of stenosis in carotid and intracranial CT angiography (CTA). Dual-energy CTA studies of 43 patients performed on a third-generation 192-slice dual-source CT were retrospectively evaluated. Intraindividual comparison of 90-kVp and linearly blended 120-kVp equivalent image series (M_0.6, 60% 90-kVp, 40% Sn-150-kVp) was performed. Contrast-to-noise and signal-to-noise ratios of common carotid artery, internal carotid artery, middle cerebral artery, and basilar artery were calculated. Qualitative image analysis included evaluation of artifacts and suitability for angiographical assessment at shoulder level, carotid bifurcation, siphon, and intracranial by three independent radiologists. Detection and quantification of carotid stenosis were performed. Radiation dose was expressed as dose-length product (DLP). Contrast-to-noise values of all arteries were significantly increased in 90-kVp compared to M_0.6 (p < 0.001). Suitability for angiographical evaluation was rated excellent with low artifacts for all levels in both image series. Both 90-kVp and M_0.6 showed excellent accordance for detection and grading of carotid stenosis with almost perfect interobserver agreement (carotid stenoses in 32 of 129 segments; intraclass correlation coefficient, 0.94). dose-length product was reduced by 40.3% in 90-kVp (110.6 ± 32.1 vs 185.4 ± 47.5 mGy·cm, p < 0.001). 90-kVp carotid and intracranial CTA with Admire provides increased quantitative and similarly good qualitative image quality, while reducing radiation exposure substantially compared to M_0.6. Diagnostic performance for arterial stenosis detection and quantification remained excellent. Advances in knowledge: 90-kVp carotid and intracranial CTA with an advanced iterative reconstruction algorithm results in

[Basic laws of blood screw motion in human common carotid arteries].

PubMed

Kulikov, V P; Kirsanov, R I

2008-08-01

The basic laws of blood screw motion in common carotid arteries in people were determined by means of modern ultrasound techniques for the first time. 92 healthy adults, aged 18-30, were examined. The blood flow in the middle one-third of common carotid arteries was registered by means of Color Doppler Imaging and impulse Doppler with the help of ultrasound Medison 8000EX scanner by linear transducer of 5-9 MHz. The steady registration of blood screw motion in both common carotid arteries in Color Doppler Imaging regimen was observed in 54.3 % of cases. The direction of screw stream rotation in most cases (54%) was multi-directed: in the right common carotid artery it was right, in the left common carotid artery--left (48%), and in 6% of cases it was reverse. For 46% of cases blood rotation in both common carotid arteries was one-directed (26%--right, 20%--left). The velocity parameters of rotation component of blood motion were determined, maximum velocity being 19.68 +/- 5.84 cm/sec, minimum--4.57 +/- 2.89 cm/sec, average--7.48 +/- 2.49 cm/sec, angular--10.7 +/- 2.49 sec(-1). The rated velocity of blood cells motion in screw motion with regard of screw current lines to the vessel vertical axis makes up from 158.67 +/- 32.79 to 224.39 +/- 46.37 cm/sec.

Device for rapid quantification of human carotid baroreceptor-cardiac reflex responses

NASA Technical Reports Server (NTRS)

Sprenkle, J. M.; Eckberg, D. L.; Goble, R. L.; Schelhorn, J. J.; Halliday, H. C.

1986-01-01

A new device has been designed, constructed, and evaluated to characterize the human carotid baroreceptor-cardiac reflex response relation rapidly. This system was designed for study of reflex responses of astronauts before, during, and after space travel. The system comprises a new tightly sealing silicon rubber neck chamber, a stepping motor-driven electrodeposited nickel bellows pressure system, capable of delivering sequential R-wave-triggered neck chamber pressure changes between +40 and -65 mmHg, and a microprocessor-based electronics system for control of pressure steps and analysis and display of responses. This new system provokes classic sigmoid baroreceptor-cardiac reflex responses with threshold, linear, and saturation ranges in most human volunteers during one held expiration.

Advances in the development of an imaging device for plaque measurement in the area of the carotid artery.

PubMed

Ličev, Lačezar; Krumnikl, Michal; Škuta, Jaromír; Babiuch, Marek; Farana, Radim

2014-03-04

This paper describes the advances in the development and subsequent testing of an imaging device for three-dimensional ultrasound measurement of atherosclerotic plaque in the carotid artery. The embolization from the atherosclerotic carotid plaque is one of the most common causes of ischemic stroke and, therefore, we consider the measurement of the plaque as extremely important. The paper describes the proposed hardware for enhancing the standard ultrasonic probe to provide a possibility of accurate probe positioning and synchronization with the cardiac activity, allowing the precise plaque measurements that were impossible with the standard equipment. The synchronization signal is derived from the output signal of the patient monitor (electrocardiogram (ECG)), processed by a microcontroller-based system, generating the control commands for the linear motion moving the probe. The controlling algorithm synchronizes the movement with the ECG waveform to obtain clear images not disturbed by the heart activity.

SPACE-2: A Missed Opportunity to Compare Carotid Endarterectomy, Carotid Stenting, and Best Medical Treatment in Patients with Asymptomatic Carotid Stenoses.

PubMed

Eckstein, H-H; Reiff, T; Ringleb, P; Jansen, O; Mansmann, U; Hacke, W

2016-06-01

Because of recent advances in best medical treatment (BMT), it is currently unclear whether any additional surgical or endovascular interventions confer additional benefit, in terms of preventing late ipsilateral carotid territory ischemic stroke in asymptomatic patients with significant carotid stenoses. The aim was to compare the stroke-preventive effects of BMT alone, with that of BMT in combination with carotid endarterectomy (CEA) or carotid artery stenting (CAS) in patients with high grade asymptomatic extracranial carotid artery stenosis. SPACE-2 was planned as a three-armed, randomized controlled trial (BMT alone vs. CEA plus BMT vs. CAS plus BMT, ISRCTN 78592017). However, because of slow patient recruitment, the three-arm study design was amended (July 2013) to become two parallel randomized studies (BMT alone vs. CEA plus BMT, and BMT alone vs. CAS plus BMT). The change in study design did not lead to any significant increase in patient recruitment, and trial recruitment ceased after recruiting 513 patients over a 5 year period (CEA vs. BMT (n = 203); CAS vs. BMT (n = 197), and BMT alone (n = 113)). The 30 day rate of death/stroke was 1.97% for patients undergoing CEA, and 2.54% for patients undergoing CAS. No strokes or deaths occurred in the first 30 days after randomization in patients randomized to BMT. There were several potential reasons for the low recruitment rates into SPACE-2, including the ability for referring doctors to refer their patients directly for CEA or CAS outwith the trial, an inability to convince patients (who had come "mentally prepared" that an intervention was necessary) to accept BMT, and other economic constraints. Because of slow recruitment rates, SPACE-2 had to be stopped after randomizing only 513 patients. The German Research Foundation will provide continued funding to enable follow up of all recruited patients, and it is also planned to include these data in any future meta-analysis prepared by the Carotid

Internal Carotid Artery Hypoplasia: Role of Color-Coded Carotid Duplex Sonography.

PubMed

Chen, Pei-Ya; Liu, Hung-Yu; Lim, Kun-Eng; Lin, Shinn-Kuang

2015-10-01

The purpose of this study was to determine the role of color-coded carotid duplex sonography for diagnosis of internal carotid artery hypoplasia. We retrospectively reviewed 25,000 color-coded carotid duplex sonograms in our neurosonographic database to establish more diagnostic criteria for internal carotid artery hypoplasia. A definitive diagnosis of internal carotid artery hypoplasia was made in 9 patients. Diagnostic findings on color-coded carotid duplex imaging include a long segmental small-caliber lumen (52% diameter) with markedly decreased flow (13% flow volume) in the affected internal carotid artery relative to the contralateral side but without intraluminal lesions. Indirect findings included markedly increased total flow volume (an increase of 133%) in both vertebral arteries, antegrade ipsilateral ophthalmic arterial flow, and a reduced vessel diameter with increased flow resistance in the ipsilateral common carotid artery. Ten patients with distal internal carotid artery dissection showed a similar color-coded duplex pattern, but the reductions in the internal and common carotid artery diameters and increase in collateral flow from the vertebral artery were less prominent than those in hypoplasia. The ipsilateral ophthalmic arterial flow was retrograde in 40% of patients with distal internal carotid artery dissection. In addition, thin-section axial and sagittal computed tomograms of the skull base could show the small diameter of the carotid canal in internal carotid artery hypoplasia and help distinguish hypoplasia from distal internal carotid artery dissection. Color-coded carotid duplex sonography provides important clues for establishing a diagnosis of internal carotid artery hypoplasia. A hypoplastic carotid canal can be shown by thin-section axial and sagittal skull base computed tomography to confirm the final diagnosis. © 2015 by the American Institute of Ultrasound in Medicine.

Role of the carotid body chemoreceptors in baroreflex control of blood pressure during hypoglycaemia in humans

PubMed Central

Limberg, Jacqueline K; Taylor, Jennifer L; Dube, Simmi; Basu, Rita; Basu, Ananda; Joyner, Michael J; Wehrwein, Erica A

2014-01-01

Activation of the carotid body chemoreceptors with hypoxia alters baroreceptor mediated responses. We aimed to examine whether this relationship can be translated to other chemoreceptor stimuli (i.e. hypoglycaemia) and hypothesized: 1) activation of the carotid body chemoreceptors with hypoglycaemia would reduce spontaneous cardiac baroreflex sensitivity (sCBRS) in healthy humans and, 2) desensitization of the carotid chemoreceptors with hyperoxia would restore sCBRS to baseline levels during hypoglycaemia. Ten young healthy adults completed two 180-min hyperinsulinaemic (2 mU.kg FFM−1.min−1), hypoglycaemic (~3.2 µmol.mL−1) clamps, separated by at least one week and randomized to normoxia (PaO2 122±10 mmHg) or hyperoxia (PaO2 424±123 mmHg; to blunt activation of the carotid body glomus cells). Changes in heart rate, blood pressure, plasma catecholamines, heart rate variability (HRV), and sCBRS were assessed. During hypoglycaemia, HRV and sCBRS were reduced (p<0.05) and the baroreflex working range was shifted to higher heart rates. When hyperoxia was superimposed on hypoglycaemia, there was a greater reduction in blood pressure and a blunted rise in heart rate when compared to normoxic conditions (p<0.05); however, there was no detectable effect of hyperoxia on sCBRS or HRV during hypoglycaemia (p>0.05). In summary, hypoglycaemia-mediated changes in HRV and sCBRS cannot be exclusively attributed to the carotid chemoreceptors; however, the chemoreceptors appear to play a role in resetting the baroreflex working range during hypoglycaemia. PMID:24414173

Carotid bruit for detection of hemodynamically significant carotid stenosis: the Northern Manhattan Study

PubMed Central

Ratchford, Elizabeth V.; Jin, Zhezhen; Di Tullio, Marco R.; Salameh, Maya J.; Homma, Shunichi; Gan, Robert; Boden-Albala, Bernadette; Sacco, Ralph L.; Rundek, Tatjana

2009-01-01

Objective The prevalence of carotid bruits and the utility of auscultation for predicting carotid stenosis are not well known. We aimed to establish the prevalence of carotid bruits and the diagnostic accuracy of auscultation for detection of hemodynamically significant carotid stenosis, using carotid duplex as the gold standard. Methods The Northern Manhattan Study (NOMAS) is a prospective multiethnic community-based cohort designed to examine the incidence of stroke and other vascular events and the association between various vascular risk factors and subclinical atherosclerosis. Of the stroke-free cohort (n=3298), 686 were examined for carotid bruits and underwent carotid duplex. Main outcome measures included prevalence of carotid bruits and sensitivity, specificity, positive predictive value, negative predictive value and accuracy of auscultation for prediction of ipsilateral carotid stenosis. Results Among 686 subjects with a mean age of 68.2 ± 9.4 years, the prevalence of ≥60% carotid stenosis as detected by ultrasound was 2.2% and the prevalence of carotid bruits was 4.1%. For detection of carotid stenosis, sensitivity of auscultation was 56%, specificity was 98%, positive predictive value was 25%, negative predictive value was 99% and overall accuracy was 97.5%. Discussion In this ethnically diverse cohort, the prevalence of carotid bruits and hemodynamically significant carotid stenosis was low. Sensitivity and positive predictive value were also low, and the 44% false-negative rate suggests that auscultation is not sufficient to exclude carotid stenosis. While the presence of a bruit may still warrant further evaluation with carotid duplex, ultrasonography may be considered in high-risk asymptomatic patients, irrespective of findings on auscultation. PMID:19133168

Clinical results of carotid artery stenting versus carotid endarterectomy

PubMed Central

Akinci, Tuba; Derle, Eda; Kibaroğlu, Seda; Harman, Ali; Kural, Feride; Cınar, Pınar; Kilinc, Munire; Akay, Hakki T.; Can, Ufuk; Benli, Ulku S.

2016-01-01

Objective: To review our results of carotid artery stenting (CAS) and carotid endarterectomy (CEA). Methods: We evaluated the medical records of patients undergoing carotid artery revascularization procedure, between 2001 and 2013 in Baskent University Hospital, Ankara, Turkey. Carotid artery stenting or CEA procedures were performed in patients with asymptomatic carotid stenosis (≥70%) or symptomatic stenosis (≥50%). Demographic data, procedural details, and clinical outcomes were recorded. Primary outcome measures were in 30-day stroke/transient ischemic attacks (TIA)/amaurosis fugax or death. Secondary outcome measures were nerve injury, bleeding complications, length of stay in hospital, stroke, restenosis (ICA patency), and all-cause death during long-term follow-up. Results: One hundred ninety-four CEA and 115 CAS procedures were performed for symptomatic and/or asymptomatic carotid artery stenosis. There is no significant differences 30-day mortality and neurologic morbidity between CAS (13%) and CEA procedures (7.7%). Length of stay in hospital were significantly longer in CEA group (p=0.001). In the post-procedural follow up, only in symptomatic patients, restenosis rate was higher in the CEA group (p=.045). The other endpoints did not differ significantly. Conclusions: Endovascular stent treatment of carotid artery atherosclerotic disease is an alternative for vascular surgery, especially for patients that are high risk for standard CEA. The increasing experience, development of cerebral protection systems and new treatment protocols increases CAS feasibility. PMID:27744460

Diabetic retinopathy is associated with the presence and burden of subclinical carotid atherosclerosis in type 1 diabetes.

PubMed

Carbonell, Marc; Castelblanco, Esmeralda; Valldeperas, Xavier; Betriu, Àngels; Traveset, Alícia; Granado-Casas, Minerva; Hernández, Marta; Vázquez, Federico; Martín, Mariona; Rubinat, Esther; Lecube, Albert; Franch-Nadal, Josep; Fernández, Elvira; Puig-Domingo, Manel; Avogaro, Angelo; Alonso, Núria; Mauricio, Dídac

2018-05-04

Cardiovascular (CV) disease due to atherosclerosis is a major cause of morbidity and mortality in adult patients with diabetes, either type 1 or type 2 diabetes. The aim of the study was to assess the association of the frequency and the burden of subclinical carotid atherosclerotic disease in patients with type 1 diabetes according to the presence and severity of diabetic retinopathy (DR). A cross-sectional study was conducted in 340 patients with type 1 diabetes (41.5% with DR), and in 304 non-diabetic individuals. All participants were free from previous CV disease and chronic kidney disease (CKD). B-mode carotid ultrasound imaging was performed in all the study subjects. Patients with type 1 diabetes underwent a full eye examination, and DR patients were divided into two groups: mild disease and advanced disease. In the group of patients with type 1 diabetes, the percentage of patients with carotid plaques was higher in those with DR compared with those without DR (44.7% vs. 24.1%, p < 0.001). Patients with DR also presented a higher incidence of ≥ 2 carotid plaques (25.5% vs. 11.1%, p < 0.001). Apart from other traditional cardiovascular risk factors, the presence of advanced stages of DR was independently associated with the presence (p = 0.044) and the burden (≥ 2 carotid plaques; p = 0.009) of subclinical carotid atherosclerosis. In patients with type 1 diabetes without previous CV disease or established CKD, the presence of advanced stages of DR is associated with a higher atherosclerotic burden in the carotid arteries. The presence of DR identifies patients at risk for carotid atherosclerotic disease.

Carotid Doppler ultrasound findings in patients with left ventricular assist devices.

PubMed

Cervini, Patrick; Park, Soon J; Shah, Dipesh K; Penev, Irina E; Lewis, Bradley D

2010-12-01

Left ventricular assist devices (LVADs) have been used to treat advanced heart failure refractory to medical management, as bridge therapy to myocardial recovery, as bridge therapy to cardiac transplantation, or as destination therapy for patients with unfavorable transplant candidacy. Neurologic complications are some of the most common and devastating complications in these patients. Preoperative carotid ultrasound is, therefore, a standard evaluation in patients at risk for cerebrovascular disease. Postoperative carotid artery Doppler sonography is performed in those patients with neurologic symptoms. It is likely, therefore, that sonographers, radiologists, and other physicians working in a center where LVADs are implanted will likely encounter a carotid artery Doppler study in this patient group. To our knowledge, the carotid Doppler findings in these patients have never been published. We review the Doppler ultrasound findings in 6 patients after LVAD insertion.

Effects of exercise pressor reflex activation on carotid baroreflex function during exercise in humans

NASA Technical Reports Server (NTRS)

Gallagher, K. M.; Fadel, P. J.; Stromstad, M.; Ide, K.; Smith, S. A.; Querry, R. G.; Raven, P. B.; Secher, N. H.

2001-01-01

1. This investigation was designed to determine the contribution of the exercise pressor reflex to the resetting of the carotid baroreflex during exercise. 2. Ten subjects performed 3.5 min of static one-legged exercise (20 % maximal voluntary contraction) and 7 min dynamic cycling (20 % maximal oxygen uptake) under two conditions: control (no intervention) and with the application of medical anti-shock (MAS) trousers inflated to 100 mmHg (to activate the exercise pressor reflex). Carotid baroreflex function was determined at rest and during exercise using a rapid neck pressure/neck suction technique. 3. During exercise, the application of MAS trousers (MAS condition) increased mean arterial pressure (MAP), plasma noradrenaline concentration (dynamic exercise only) and perceived exertion (dynamic exercise only) when compared to control (P < 0.05). No effect of the MAS condition was evident at rest. The MAS condition had no effect on heart rate (HR), plasma lactate and adrenaline concentrations or oxygen uptake at rest and during exercise. The carotid baroreflex stimulus-response curve was reset upward on the response arm and rightward to a higher operating pressure by control exercise without alterations in gain. Activation of the exercise pressor reflex by MAS trousers further reset carotid baroreflex control of MAP, as indicated by the upward and rightward relocation of the curve. However, carotid baroreflex control of HR was only shifted rightward to higher operating pressures by MAS trousers. The sensitivity of the carotid baroreflex was unaltered by exercise pressor reflex activation. 4. These findings suggest that during dynamic and static exercise the exercise pressor reflex is capable of actively resetting carotid baroreflex control of mean arterial pressure; however, it would appear only to modulate carotid baroreflex control of heart rate.

Guidelines for patient selection and performance of carotid artery stenting.

PubMed

Bladin, Christopher; Chambers, Brian; New, Gishel; Denton, Michael; Lawrence-Brown, Michael

2010-06-01

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. We applied a modified Delphi consensus method of iterative consultation between the College representatives on the Carotid Stenting Guidelines Committee (CSGC). 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

Predicting carotid artery disease and plaque instability from cell-derived microparticles.

PubMed

Wekesa, A L; Cross, K S; O'Donovan, O; Dowdall, J F; O'Brien, O; Doyle, M; Byrne, L; Phelan, J P; Ross, M D; Landers, R; Harrison, M

2014-11-01

Cell-derived microparticles (MPs) are small plasma membrane-derived vesicles shed from circulating blood cells and may act as novel biomarkers of vascular disease. We investigated the potential of circulating MPs to predict (a) carotid plaque instability and (b) the presence of advanced carotid disease. This pilot study recruited carotid disease patients (aged 69.3 ± 1.2 years [mean ± SD], 69% male, 90% symptomatic) undergoing endarterectomy (n = 42) and age- and sex-matched controls (n = 73). Plaques were classified as stable (n = 25) or unstable (n = 16) post surgery using immunohistochemistry. Blood samples were analysed for MP subsets and molecular biomarkers. Odds ratios (OR) are expressed per standard deviation biomarker increase. Endothelial MP (EMP) subsets, but not any vascular, inflammatory, or proteolytic molecular biomarker, were higher (p < .05) in the unstable than the stable plaque patients. The area under the receiver operator characteristic curve for CD31(+)41(-) EMP in discriminating an unstable plaque was 0.73 (0.56-0.90, p < .05). CD31(+)41(-) EMP predicted plaque instability (OR = 2.19, 1.08-4.46, p < .05) and remained significant in a multivariable model that included transient ischaemic attack symptom status. Annexin V(+) MP, platelet MP (PMP) subsets, and C-reactive protein were higher (p < .05) in cases than controls. Annexin V(+) MP (OR = 3.15, 1.49-6.68), soluble vascular cell adhesion molecule-1 (OR = 1.64, 1.03-2.59), and previous smoking history (OR = 3.82, 1.38-10.60) independently (p < .05) predicted the presence of carotid disease in a multivariable model. EMP may have utility in predicting plaque instability in carotid patients and annexin V(+) MPs may predict the presence of advanced carotid disease in aging populations, independent of established biomarkers. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Effect of dynamic exercise on human carotid-cardiac baroreflex latency

NASA Technical Reports Server (NTRS)

Potts, J. T.; Raven, P. B.

1995-01-01

We compared the beat-to-beat responses of heart rate (HR) after brief activation of carotid baroreceptors in resting humans with the responses obtained during mild-to-moderate levels of dynamic exercise [25 and 50% of peak O2 uptake (VO2peak)] to investigate the effect of exercise on baroreflex latency. Carotid baroreceptors were activated by a pressure pulse (5 s) of neck suction (NS, -80 Torr) and neck pressure (NP, +40 Torr) during held expiration. At rest the peak change in HR to NS/NP occurred during the first several heartbeats (1st-3rd beat), whereas during mild and moderate exercise peak HR responses occurred near the end of the NS/NP pulse (6th-8th beat). In contrast, time (s) to the peak change in HR was not different between rest and exercise (P > 0.05). Reflex tachycadia to NP progressively decreased during exercise (17 +/- 3, 10 +/- 1, and 4 +/- 1% of control, rest vs. 25% VO2peak, vs. 50% VO2peak, respectively, P < 0.05), and a strong positive correlation was found between the magnitude of the reflex tachycardia and a measure of HR variability (cardiac vagal tone index, r = 0.74, P < 0.0001). Reflex bradycardia to NS gradually increased during exercise (13 +/- 2, 17 +/- 2, and 18 +/- 2% of control, rest vs. 25% VO2peak, vs. 50% VO2peak, respectively, P = 0.10) and was negatively correlated with cardiac vagal tone (r = 0.42, P < 0.06).(ABSTRACT TRUNCATED AT 250 WORDS).

Advanced glycation end products, carotid atherosclerosis, and circulating endothelial progenitor cells in patients with end-stage renal disease.

PubMed

Ueno, Hiroki; Koyama, Hidenori; Fukumoto, Shinya; Tanaka, Shinji; Shoji, Takuhito; Shoji, Tetsuo; Emoto, Masanori; Tahara, Hideki; Inaba, Masaaki; Kakiya, Ryusuke; Tabata, Tsutomu; Miyata, Toshio; Nishizawa, Yoshiki

2011-04-01

Numbers of endothelial progenitor cells (EPCs) have been shown to be decreased in subjects with end-stage renal disease (ESRD), the mechanism of which remained poorly understood. In this study, mutual association among circulating EPC levels, carotid atherosclerosis, serum pentosidine, and skin autofluorescence, a recently established noninvasive measure of advanced glycation end products accumulation, was examined in 212 ESRD subjects undergoing hemodialysis. Numbers of circulating EPCs were measured as CD34+ CD133+ CD45(low) VEGFR2+ cells and progenitor cells as CD34+ CD133+ CD45(low) fraction by flow cytometry. Skin autofluorescence was assessed by the autofluorescence reader; and serum pentosidine, by enzyme-linked immunosorbent assay. Carotid atherosclerosis was determined as intimal-medial thickness (IMT) measured by ultrasound. Circulating EPCs were significantly and inversely correlated with skin autofluorescence in ESRD subjects (R = -0.216, P = .002), but not with serum pentosidine (R = -0.079, P = .25). Circulating EPCs tended to be inversely associated with IMT (R = -0.125, P = .069). Intimal-medial thickness was also tended to be correlated positively with skin autofluorescence (R = 0.133, P = .054) and significantly with serum pentosidine (R = 0.159, P = .019). Stepwise multiple regression analyses reveal that skin autofluorescence, but not serum pentosidine and IMT, was independently associated with low circulating EPCs. Of note, skin autofluorescence was also inversely and independently associated with circulating progenitor cells. Thus, tissue accumulated, but not circulating, advanced glycation end products may be a determinant of a decrease in circulating EPCs in ESRD subjects. Copyright © 2011 Elsevier Inc. All rights reserved.

Cervical Carotid and Circle of Willis Arterial Anatomy of Macaque Monkeys: A Comparative Anatomy Study

PubMed Central

Kumar, Nishant; Lee, John J.; Perlmutter, Joel S.; Derdeyn, Colin P.

2009-01-01

Macaque monkeys are used in many research applications, including cerebrovascular investigations. However, detailed catalogs of the relevant vascular anatomy are scarce. We present our experience with macaque vessel patterns as determined by digital subtraction angiography of 34 different monkeys. METHODS AND MATERIALS: We retrospectively analyzed digital subtraction angiograms obtained during experimental internal carotid artery catheterization and subsequent injection of 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine (MPTP). Results were catalogued according to vascular distribution and variants observed. RESULTS: Macaque monkeys have a bovine aortic arch. The carotid vessels generally bifurcate, but are occasionally observed to divide into three vessels. The external carotid gives rise primarily to two trunks: an occipital branch and a common vessel that subsequently gives off the lingual, facial, and superior thyroid arteries. The internal maxillary artery may be present as a terminal branch of the external carotid or as a branch of the occipital artery. The internal carotid artery is similar in course to that of the human. The anterior circle of Willis was intact in all monkeys in our study. Its primary difference from that of the human is the union of the bilateral anterior cerebral arteries as a single (azygous) median vessel. CONCLUSIONS: Macaque cervical carotid and circle of Willis arterial anatomy differs from humans in a couple of specific patterns. Knowledge of these differences and similarities between human and macaque anatomy is important in developing endovascular macaque models of human diseases, such as ischemic stroke. PMID:19434671

Artificial embolization of carotid-cavernous fistula with post-operative patency of internal carotid artery

PubMed Central

Isamat, Fabian; Salleras, V.; Miranda, A. M.

1970-01-01

This report deals with a patient of 86 who developed a carotid-cavernous fistula. Artificial embolization alone was considered the safest treatment for this patient and proved to be adequate. Post-operative preservation of the patency of the internal carotid artery was demonstrated by angiography. We believe this method is particularly appropriate for carotid-cavernous fistulas if it is demonstrated by angiography that the major blood flow of the carotid artery pours into the fistula. A soft-iron clip attached to the muscle can be used for external and forceful guidance of the embolus into the fistula with the help of an electromagnet, hence the patency of the internal carotid artery can be preserved. The embolus should be introduced through the external carotid artery. This is the only case known to us in which patency of the internal carotid artery was post-operatively maintained. We have reviewed 545 reported cases of surgically treated carotid-cavernous fistulas and analysed the results from simple cervical carotid ligation to the more sophisticated methods of artificial embolizations. The results obtained by artificial embolization have been consistently good, while the other techniques have failed in large percentages. Artificial embolization should be used as the primary treatment for carotid-cavernous fistula, since ligation of the internal carotid artery precludes its embolization at a later date. Images PMID:5478949

Guidelines for patient selection and performance of carotid artery stenting.

PubMed

2009-12-01

The endovascular treatment of carotid atherosclerosis with carotid artery stenting (CAS) remains controversial. Carotid endarterectomy (CEA) remains the benchmark in terms of procedural mortality and morbidity. Consensus Australasian guidelines for the safe performance of CAS were developed using the modified Delphi consensus method of iterative consultation. Selection of patients suitable for CAS needs careful consideration of clinical and patho-anatomical criteria. Randomised controlled trials and pooled analyses have demonstrated that CAS is more hazardous than CEA. The CGSC therefore recommends that CAS should not be performed in the majority of patients requiring carotid revascularisation. 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 randomised controlled trials, carotid and aortic arch anatomy and pathology, and recognition and management of periprocedural complications. It is critical that all patients being considered for a carotid intervention have adequate pre-procedural neuroimaging and peri-procedural, independent, neurological assessment. Maintenance of proficiency in CAS requires active involvement in surgical/endovascular audit and continuing medical education programmes. These standards should apply in the public and private health-care settings. These guidelines represent the consensus of an intercollegiate committee in order to direct appropriate patient selection to perform CAS. Advances in endovascular technologies and the results of randomised controlled trials will guide future revisions of this document.

Ultrasonographic character of carotid plaque and postprocedural brain embolisms in carotid artery stenting and carotid endarterectomy.

PubMed

Mitsuoka, Hiroshi; Shintani, Tsunehiro; Furuya, Hidekazu; Nakao, Yoshinaga; Higashi, Shigeki

2011-01-01

To investigate ultrasonographic character of carotid plaques, and incidences of brain embolism in carotid angioplasty and stenting (CAS) and carotid endarterectomy (CEA). CEA (22/25 symptomatic lesions) and CAS (17/20 symptomatic lesions) between 2007 and 2010. Embolic protection devices (15 occlusion and 5 filtering devices) were used during CAS. Carotid plaques were classified into three categories (I: calcificated, II: intermediately echogenic, III: echolucent). Magnetic resonance imaging (MRI) was used to investigate brain emboli. Ultrasonographic character of the plaques in CEA cases (I: 4%, II: 88%, III: 8%) was different from the one in CAS cases (I: 10%, II: 90%, III: 0%). The incidence of brain embolism in the CAS cases was 52.6% while 0% in the CEA cases (p = 0.00037). CAS had high incidences of brain embolism in any plaques (I: 100%, II: 43.8%). In the most recent 9 procedures of CAS using occlusion devices, averaged number of embolic lesion was 1.0 (0 post operative day; 0 POD). The number increased as 1.4 (1 POD) and 2.0 (7 POD). CEA should be currently the first choice for most patients with a high-grade and symptomatic carotid artery stenosis.

Meta-analysis and meta-regression analysis of outcomes of carotid endarterectomy and stenting in the elderly.

PubMed

Antoniou, George A; Georgiadis, George S; Georgakarakos, Efstratios I; Antoniou, Stavros A; Bessias, Nikos; Smyth, John Vincent; Murray, David; Lazarides, Miltos K

2013-12-01

Uncertainty exists about the influence of advanced age on the outcomes of carotid revascularization. To undertake a comprehensive review of the literature and conduct an analysis of the outcomes of carotid interventions in the elderly. A systematic literature review was conducted to identify articles comparing early outcomes of carotid endarterectomy (CEA) or carotid stenting (CAS) in elderly and young patients. Combined overall effect sizes were calculated using fixed or random effects models. Meta-regression models were formed to explore potential heterogeneity as a result of changes in practice over time. RESULTS Our analysis comprised 44 studies reporting data on 512,685 CEA and 75,201 CAS procedures. Carotid stenting was associated with increased incidence of stroke in elderly patients compared with their young counterparts (odds ratio [OR], 1.56; 95% CI, 1.40-1.75), whereas CEA had equivalent cerebrovascular outcomes in old and young age groups (OR, 0.94; 95% CI, 0.88-0.99). Carotid stenting had similar peri-interventional mortality risks in old and young patients (OR, 0.86; 95% CI, 0.72-1.03), whereas CEA was associated with heightened mortality in elderly patients (OR, 1.62; 95% CI, 1.47-1.77). The incidence of myocardial infarction was increased in patients of advanced age in both CEA and CAS (OR, 1.64; 95% CI, 1.57-1.72 and OR, 1.30; 95% CI, 1.16-1.45, respectively). Meta-regression analyses revealed a significant effect of publication date on peri-interventional stroke (P = .003) and mortality (P < .001) in CAS. Age should be considered when planning a carotid intervention. Carotid stenting has an increased risk of adverse cerebrovascular events in elderly patients but mortality equivalent to younger patients. Carotid endarterectomy is associated with similar neurologic outcomes in elderly and young patients, at the expense of increased mortality.

Intraplaque hemorrhage, a potential consequence of periodontal bacteria gathering in human carotid atherothrombosis.

PubMed

Brun, Adrian; Rangé, Hélène; Prouvost, Bastien; Meilhac, Olivier; Mazighi, Mikael; Amarenco, Pierre; Lesèche, Guy; Bouchard, Philippe; Michel, Jean-Baptiste

2016-06-28

Periodontal diseases are multifactorial inflammatory diseases, caused by a bacterial biofilm involving both innate and adaptative immunity, characterized by the destruction of tooth-supporting tissues. In the context of periodontitis, the spread of weak pathogenic bacteria into the bloodstream has been described. These bacteria will preferentially localize to existing clot within the circulation. Atherothrombosis of the carotid arteries is a local pathology and a common cause of cerebral infarction. Intraplaque hemorrhages render the lesion more prone to clinical complications such as stroke. The main objective of this study is to explore the biological relationship between carotid intraplaque hemorrhage and periodontal diseases. This study included consecutive patients with symptomatic or asymptomatic carotid stenosis, admitted for endarterectomy surgical procedure (n=41). In conditioned media of the carotid samples collected, markers of neutrophil activation (myeloperoxidase or MPO, DNA-MPO complexes) and hemoglobin were quantified. To investigate the presence of DNA from periodontal bacteria in atherosclerotic plaque, PCR analysis using specific primers was performed. Our preliminary results indicate an association between neutrophil activation and intraplaque hemorrhages, reflected by the release of MPO (p<0,01) and MPO-DNA complexes (p<0,05). Presence of DNA from periodontitis-associated bacteria was found in 32/41 (78%) atheromatous plaque samples. More specifically, DNA from Pg, Tf, Pi, Aa was found in 46%, 24%, 34% and 68% of the samples, respectively. Hemoglobin levels were higher in conditioned media in carotid samples where the bacteria were found, but this was not statistically significant. Our data confirm the relationship between intraplaque hemorrhage and neutrophil activation. In addition, the presence of periodontal bacteria DNA in carotid atheromatous plaque, may contribute to this activation. Further analysis is needed to fully explore the

In vivo MRI-based simulation of fatigue process: a possible trigger for human carotid atherosclerotic plaque rupture.

PubMed

Huang, Yuan; Teng, Zhongzhao; Sadat, Umar; He, Jing; Graves, Martin J; Gillard, Jonathan H

2013-04-23

Atherosclerotic plaque is subjected to a repetitive deformation due to arterial pulsatility during each cardiac cycle and damage may be accumulated over a time period causing fibrous cap (FC) fatigue, which may ultimately lead to rupture. In this study, we investigate the fatigue process in human carotid plaques using in vivo carotid magnetic resonance (MR) imaging. Twenty seven patients with atherosclerotic carotid artery disease were included in this study. Multi-sequence, high-resolution MR imaging was performed to depict the plaque structure. Twenty patients were found with ruptured FC or ulceration and 7 without. Modified Paris law was used to govern crack propagation and the propagation direction was perpendicular to the maximum principal stress at the element node located at the vulnerable site. The predicted crack initiations from 20 patients with FC defect all matched with the locations of the in vivo observed FC defect. Crack length increased rapidly with numerical steps. The natural logarithm of fatigue life decreased linearly with the local FC thickness (R(2) = 0.67). Plaques (n=7) without FC defect had a longer fatigue life compared with those with FC defect (p = 0.03). Fatigue process seems to explain the development of cracks in FC, which ultimately lead to plaque rupture.

[A case of internal carotid artery stenosis with discontinuance of carotid endarterectomy due to the tight adhesions around the internal carotid artery].

PubMed

Kohri, Ryusuke; Miyazono, Masayuki; Hatae, Ryusuke; Maeda, Kazushi; Takahira, Asuka; Maeda, Yasuhiro; Mizota, Takamitsu; Naito, Shinji

2012-05-01

A 73-year-old female visited her local doctor after repeatedly experiencing temporary weakness in her left upper and lower extremities. The patient underwent a cervical magnetic resonance imaging (MRI) scan and was diagnosed with right internal carotid artery stenosis. Despite administration of antiplatelet drugs, her symptoms continued, and she was referred to our department for medical treatment. Her medical history revealed hypertension, hyperlipidemia, and cholesteatoma. We diagnosed symptomatic internal carotid artery stenosis and performed carotid endarterectomy (CEA). However, tight adhesions between the carotid artery and surrounding tissue made separation difficult, and surgery had to be discontinued. Some of the extracted adherent tissue consisted of hyalinized fibrous tissue that had the appearance of soft tissue which had organized because of inflammation. Although there have been no reports of cholesteatoma directly causing adhesion around the internal carotid artery, it has been reported to have led to abscess formation in the parapharyngeal space adjacent to the carotid space. Because the boundaries of the parapharyngeal space and carotid space are anatomically incomplete, inflammation often affects the area between them. As far as we know, this report, which also includes a discussion of the literature, is the first to indicate that cholesteatoma causes strong adhesions around the carotid artery.

Contemporary carotid imaging: from degree of stenosis to plaque vulnerability.

PubMed

Brinjikji, Waleed; Huston, John; Rabinstein, Alejandro A; Kim, Gyeong-Moon; Lerman, Amir; Lanzino, Giuseppe

2016-01-01

Carotid artery stenosis is a well-established risk factor of ischemic stroke, contributing to up to 10%-20% of strokes or transient ischemic attacks. Many clinical trials over the last 20 years have used measurements of carotid artery stenosis as a means to risk stratify patients. However, with improvements in vascular imaging techniques such as CT angiography and MR angiography, ultrasonography, and PET/CT, it is now possible to risk stratify patients, not just on the degree of carotid artery stenosis but also on how vulnerable the plaque is to rupture, resulting in ischemic stroke. These imaging techniques are ushering in an emerging paradigm shift that allows for risk stratifications based on the presence of imaging features such as intraplaque hemorrhage (IPH), plaque ulceration, plaque neovascularity, fibrous cap thickness, and presence of a lipid-rich necrotic core (LRNC). It is important for the neurosurgeon to be aware of these new imaging techniques that allow for improved patient risk stratification and outcomes. For example, a patient with a low-grade stenosis but an ulcerated plaque may benefit more from a revascularization procedure than a patient with a stable 70% asymptomatic stenosis with a thick fibrous cap. This review summarizes the current state-of-the-art advances in carotid plaque imaging. Currently, MRI is the gold standard in carotid plaque imaging, with its high resolution and high sensitivity for identifying IPH, ulceration, LRNC, and inflammation. However, MRI is limited due to time constraints. CT also allows for high-resolution imaging and can accurately detect ulceration and calcification, but cannot reliably differentiate LRNC from IPH. PET/CT is an effective technique to identify active inflammation within the plaque, but it does not allow for assessment of anatomy, ulceration, IPH, or LRNC. Ultrasonography, with the aid of contrast enhancement, is a cost-effective technique to assess plaque morphology and characteristics, but it is

Cerebral hemodynamic changes and electroencephalography during carotid endarterectomy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Algotsson, L.; Messeter, K.; Rehncrona, S.

Some patients undergoing endarterectomy for occlusive carotid artery disease run a risk of brain ischemia during cross-clamping of the artery. The present study of 15 patients was undertaken to evaluate changes in cerebral blood flow (CBF), as measured with an intravenous (IV) tracer (133Xenon) technique, and to relate CBF changes to changes in the electroencephalogram (EEG). CBF was measured before and after induction of anesthesia, during cross-clamping of the carotid artery, after release of the clamps, and at 24 hours after the operation. All the patients were anesthetized with methohexitone, fentanyl, and nitrous oxide and oxygen. EEG was continuously recordedmore » during the operation. Carotid artery shunts were not used. In 8 patients, cross-clamping of the carotid artery did not influence the EEG. In this group of patients, induction of anesthesia caused a 38% decrease in CBF, which presumably reflects the normal reaction to the anesthetic agent given. There were no further changes in CBF during cross-clamping. In 7 patients, the EEG showed signs of deterioration during the intraoperative vascular occlusion. In these patients, anesthesia did not cause any CBF change, whereas cross-clamping the artery induced a 33% decrease in CBF. In individual patients, the severity of EEG changes correlated with the decrease in CBF. The absence of a change in CBF by anesthesia and a decrease due to cross-clamping of the carotid artery may be explained by the presence of a more advanced cerebrovascular disease and an insufficiency to maintain CBF during cross-clamping.« less

Hyperadditive Ventilatory Response Arising from Interaction between the Carotid Chemoreflex and the Muscle Mechanoreflex in Healthy Humans.

PubMed

Silva, Talita M; Aranda, Liliane C; Paula-Ribeiro, Marcelle; Oliveira, Diogo M; Medeiros, Wladimir Musetti; Vianna, Lauro C; Nery, Luiz E; Silva, Bruno M

2018-03-22

Physical exercise potentiates the carotid chemoreflex control of ventilation (VE). Hyperadditive neural interactions may partially mediate the potentiation. However, some neural interactions remain incompletely explored. As the potentiation occurs even during low-intensity exercise, we tested the hypothesis that the carotid chemoreflex and the muscle mechanoreflex could interact in a hyperadditive fashion. Fourteen young healthy subjects inhaled, randomly, in separate visits, 12% O 2 to stimulate the carotid chemoreflex, and 21% O 2 as control. A rebreathing circuit maintained isocapnia. During gases administration, subjects either remained at rest (i.e., normoxic and hypoxic rest) or the muscle mechanoreflex was stimulated, via passive knee movement (i.e., normoxic and hypoxic movement). Surface muscle electrical activity did not increase during the passive movement, confirming the absence of active contractions. Hypoxic rest and normoxic movement similarly increased VE [change (mean {plus minus} SEM) = 1.24 {plus minus} 0.72 vs. 0.73 {plus minus} 0.43 L/min, respectively; P = 0.46], but hypoxic rest only increased tidal volume (Vt) and normoxic movement only increased breathing frequency (BF). Hypoxic movement induced greater VE and mean inspiratory flow (Vt/Ti) increase than the sum of hypoxic rest and normoxic movement isolated responses (VE change: hypoxic movement = 3.72 {plus minus} 0.81 vs. sum = 1.96 {plus minus} 0.83 L/min, P = 0.01; Vt/Ti change: hypoxic movement = 0.13 {plus minus} 0.03 vs. sum = 0.06 {plus minus} 0.03 L/s, P = 0.02). Moreover, hypoxic movement increased both Vt and BF. Collectively, the results indicate the carotid chemoreflex and the muscle mechanoreflex interacted mediating a hyperadditive ventilatory response in healthy humans.

Perinatal nicotine/smoking exposure and carotid chemoreceptors during development.

PubMed

Stéphan-Blanchard, E; Bach, V; Telliez, F; Chardon, K

2013-01-01

Tobacco smoking is still a common habit during pregnancy and is the most important preventable cause of many adverse perinatal outcomes. Prenatal smoking exposure can produce direct actions of nicotine in the fetus with the disruption of body and brain development, and actions on the maternal-fetal unit by causing repeated episodes of hypoxia and exposure to many toxic smoke products (such as carbon monoxide). Specifically, nicotine through binding to nicotinic acetylcholine receptors have ubiquitous effects and can affect carotid chemoreception development through structural, functional and neuroregulatory alterations of the neural circuits involved in the chemoafferent pathway, as well as by interfering with the postnatal resetting of the carotid bodies. Reduced carotid body chemosensitivity and tonic activity have thus been reported by the majority of the human and animal studies. This review focuses on the effects of perinatal exposure to tobacco smoke and nicotine on carotid chemoreceptor function during the developmental period. A description of the effects of smoking and nicotine on the control of breathing related to carotid body activity, and of the possible physiopathological mechanisms at the origin of these disturbances is presented. Copyright © 2012 Elsevier B.V. All rights reserved.

Evaluation of carotid intima-media thickness and carotid arterial stiffness in children with adenotonsillar hypertrophy.

PubMed

Çiftel, Murat; Demir, Berrin; Kozan, Günay; Yılmaz, Osman; Kahveci, Hasan; Kılıç, Ömer

2016-02-01

Adenotonsillar hypertrophy can produce cardiopulmonary disease in children. However, it is unclear whether adenotonsillar hypertrophy causes atherosclerosis. This study evaluated carotid intimamedia thickness and carotid arterial stiffness in children with adenotonsillar hypertrophy. The study included 40 children with adenotonsillar hypertrophy (age: 5-10 years) and 36 healthy children with similar age and body mass index. Systolic blood pressure, diastolic blood pressure, and pulse pressure were measured in all subjects. Carotid intima-media thickness, carotid arterial systolic diameter, and carotid arterial diastolic diameter were measured using a high-resolution ultrasound device. Based on these measurements, carotid arterial strain, carotid artery distensibility, beta stiffness index, and elasticity modulus were calculated. Carotid intima-media thickness was greater in children with adenotonsillar hypertrophy (0.36±0.05 mm vs. 0.34±0.04 mm, P=0.02) compared to healthy controls. Beta stiffness index (3.01±1.22 vs. 2.98±0.98, P=0.85), elasticity modulus (231.39±99.23 vs. 226.46±83.20, P=0.88), carotid arterial strain (0.17±0.06 vs. 0.17±0.04, P=0.95), and carotid artery distensibility (13.14±3.88 vs. 12.92±3.84, P=0.75) were similar between children with adenotonsillar hypertrophy and the healthy controls. The present study revealed increased carotid intima-media thickness in children with adenotonsillar hypertrophy. The risk of subclinical atherosclerosis may be higher in children with adenotonsillar hypertrophy.

Tissue Vibration Induces Carotid Artery Endothelial Dysfunction: A Mechanism Linking Snoring and Carotid Atherosclerosis?

PubMed Central

Cho, Jin-Gun; Witting, Paul K.; Verma, Manisha; Wu, Ben J.; Shanu, Anu; Kairaitis, Kristina; Amis, Terence C.; Wheatley, John R.

2011-01-01

Study Objectives: We have previously identified heavy snoring as an independent risk factor for carotid atherosclerosis. In order to explore the hypothesis that snoring-associated vibration of the carotid artery induces endothelial dysfunction (an established atherogenic precursor), we utilized an animal model to examine direct effects of peri-carotid tissue vibration on carotid artery endothelial function and structure. Design: In supine anesthetized, ventilated rabbits, the right carotid artery (RCA) was directly exposed to vibrations for 6 h (peak frequency 60 Hz, energy matched to that of induced snoring in rabbits). Similarly instrumented unvibrated rabbits served as controls. Features of OSA such as hypoxemia, large intra-pleural swings and blood pressure volatility were prevented. Carotid endothelial function was then examined: (1) biochemically by measurement of tissue cyclic guanosine monophosphate (cGMP) to acetylcholine (ACh) and sodium nitroprusside (SNP); and (2) functionally by monitoring vessel relaxation with acetylcholine in a myobath. Measurement and Results: Vessel cGMP after stimulation with ACh was reduced in vibrated RCA compared with unvibrated (control) arteries in a vibration energy dose-dependent manner. Vibrated RCA also showed decreased vasorelaxation to ACh compared with control arteries. Notably, after addition of SNP (nitric oxide donor), cGMP levels did not differ between vibrated and control arteries, thereby isolating vibration-induced dysfunction to the endothelium alone. This dysfunction occurred in the presence of a morphologically intact endothelium without increased apoptosis. Conclusions: Carotid arteries subjected to 6 h of continuous peri-carotid tissue vibration displayed endothelial dysfunction, suggesting a direct plausible mechanism linking heavy snoring to the development of carotid atherosclerosis. Citation: Cho JG; Witting PK; Verma M; Wu BJ; Shanu A; Kairaitis K; Amis TC; Wheatley JR. Tissue vibration induces

Cervical carotid and circle of willis arterial anatomy of macaque monkeys: a comparative anatomy study.

PubMed

Kumar, Nishant; Lee, John J; Perlmutter, Joel S; Derdeyn, Colin P

2009-07-01

Macaque monkeys are used in many research applications, including cerebrovascular investigations. However, detailed catalogs of the relevant vascular anatomy are scarce. We present our experience with macaque vessel patterns as determined by digital subtraction angiography of 34 different monkeys. We retrospectively analyzed digital subtraction angiograms obtained during experimental internal carotid artery (ICA) catheterization and subsequent injection of 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine. Results were catalogued according to vascular distribution and variants observed. Macaque monkeys have a bovine aortic arch. The carotid vessels generally bifurcate, but are occasionally observed to divide into three vessels. The external carotid gives rise primarily to two trunks: an occipital branch and a common vessel that subsequently gives off the lingual, facial, and superior thyroid arteries. The internal maxillary artery may be present as a terminal branch of the external carotid or as a branch of the occipital artery. The ICA is similar in course to that of the human. The anterior circle of Willis was intact in all monkeys in our study. Its primary difference from that of the human is the union of the bilateral anterior cerebral arteries as a single (azygous) median vessel. Macaque cervical carotid and circle of Willis arterial anatomy differs from humans in a couple of specific patterns. Knowledge of these differences and similarities between human and macaque anatomy is important in developing endovascular macaque models of human diseases, such as ischemic stroke.

Covered stent graft for treatment of a pseudoaneurysm and carotid blowout syndrome

PubMed Central

Janjua, Nazli; Alkawi, Ammar; Georgiadis, Alexandros L.; Kirmani, Jawad F.; Qureshi, Adnan I.

2008-01-01

Background Carotid blowout syndrome with pseudoaneurysm, a rapidly progressive pathology, may present emergently with massive oral hemorrhage. Use of an endograft prosthesis offers a treatment strategy with salvation of the carotid artery. Case History: A 55 year old man with advanced squamous cell carcinoma of the head and neck presented with recurrent transoral hemorrhage, requiring endovascular treatment. Technical Report: Coil embolization was initially performed with little impact on the hemorrhage. A 7 x 40 mm Fluency® Plus covered stent (Bard Peripheral Vascular, Tempe, Arizona, USA) was placed and was supplemented by a second 8 x 40 mm Fluency Plus stent, with resulting cessation of active contrast extravasation. Discussion: The risks and benefits of various treatment options of carotid pseudoaneurysm with blowout are discussed including the use or omission of antiplatelet and anticoagulant regimens, with reference to previously reported cases. Conclusion: Tandem, overlapping covered stent placement in the common carotid artery is feasible and offers a treatment option for carotid blowout syndrome. Risks of aggravation of hemorrhage versus long-term thromboembolic events without antiplatelet therapy must be considered in cases of active ongoing hemorrhage. PMID:22518207

Resolution of carotid stenosis pre-carotid intervention: A case for selective preoperative duplex ultrasound.

PubMed

Ali, Abid; Ashrafi, Mohammed; Zeynali, Iraj

2015-01-01

Spontaneous resolution of carotid stenosis is a phenomenon that has been described in literature in the past. At present it is not routine practise to scan patients prior to carotid endarterectomy surgery within the UK. A 58 year old female presented to hospital with a history of sudden onset headache and left sided weakness. CT head showed findings in keeping with an acute right MCA territory infarct. A duplex ultrasound scan showed echolucent material in the right internal carotid artery forming a greater than 95% stenosis. The scan was unable to visualise the patency of the vessel distally due to the position of the mandible. The patient was provisionally listed for carotid endarterectomy. An MRA was requested prior to surgery to assess the patency of the distal internal carotid artery. The MRA of the carotids showed normal appearance of the common carotid, internal and vertebral arteries with no definite stenosis. A repeat duplex ultrasound confirmed there was no significant stenosis. The finding of complete resolution of stenosis on MRA was an unexpected event. Had the initial duplex imaging allowed visualisation of the distal vessel patency, our patient would have undergone unnecessary carotid surgery with the associated morbidity and mortality. This case report draws attention to the benefits of selective preoperative scanning, in sparing patients from unnecessary surgery as a result of finding occlusion or resolution of a previously diagnosed carotid stenosis. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Carotid Artery Disease

MedlinePlus

... head with blood. If you have carotid artery disease, the arteries become narrow or blocked, usually because ... other substances found in the blood. Carotid artery disease is serious because it can block the blood ...

Infrasonic analysis of carotid vibration as a diagnostic method in carotid insufficiency syndrome.

PubMed

Anastassiades, A J; Petounis, A D

1976-01-01

The infrasonic part of the spectrum of the carotid artery wall vibration in the neck was obtained. Differences between the spectral content and vibrational amplitude in normal and occluded carotids were found. The application of this technique in clinical practice could be useful in the detection of the carotid insufficiency syndrome.

Computational modeling of hypertensive growth in the human carotid artery

NASA Astrophysics Data System (ADS)

Sáez, Pablo; Peña, Estefania; Martínez, Miguel Angel; Kuhl, Ellen

2014-06-01

Arterial hypertension is a chronic medical condition associated with an elevated blood pressure. Chronic arterial hypertension initiates a series of events, which are known to collectively initiate arterial wall thickening. However, the correlation between macrostructural mechanical loading, microstructural cellular changes, and macrostructural adaptation remains unclear. Here, we present a microstructurally motivated computational model for chronic arterial hypertension through smooth muscle cell growth. To model growth, we adopt a classical concept based on the multiplicative decomposition of the deformation gradient into an elastic part and a growth part. Motivated by clinical observations, we assume that the driving force for growth is the stretch sensed by the smooth muscle cells. We embed our model into a finite element framework, where growth is stored locally as an internal variable. First, to demonstrate the features of our model, we investigate the effects of hypertensive growth in a real human carotid artery. Our results agree nicely with experimental data reported in the literature both qualitatively and quantitatively.

Propionibacterium acnes Recovered from Atherosclerotic Human Carotid Arteries Undergoes Biofilm Dispersion and Releases Lipolytic and Proteolytic Enzymes in Response to Norepinephrine Challenge In Vitro

PubMed Central

Lanter, Bernard B.

2015-01-01

In the present study, human atherosclerotic carotid arteries were examined following endarterectomy for the presence of the Gram-positive bacterium Propionibacterium acnes and its potential association with biofilm structures within the arterial wall. The P. acnes 16S rRNA gene was detectable in 4 of 15 carotid artery samples, and viable P. acnes was one among 10 different bacterial species recoverable in culture. Fluorescence in situ hybridization analysis of 5 additional atherosclerotic carotid arteries demonstrated biofilm bacteria within all samples, with P. acnes detectable in 4 samples. We also demonstrated that laboratory-grown cultures of P. acnes biofilms were susceptible to induction of a biofilm dispersion response when challenged with physiologically relevant levels of norepinephrine in the presence of iron-bound transferrin or with free iron. The production and release of lipolytic and proteolytic extracellular enzymes by P. acnes were shown to increase in iron-induced dispersed biofilms, and these dispersion-induced P. acnes VP1 biofilms showed increased expression of mRNAs for the triacylglycerol lipases PPA2105 and PPA1796 and the hyaluronate lyase PPA380 compared to that in untreated biofilms. These results demonstrate that P. acnes can infect the carotid arteries of humans with atherosclerosis as a component of multispecies biofilms and that dispersion is inducible for this organism, at least in vitro, with physiologically relevant levels of norepinephrine resulting in the production and release of degradative enzymes. PMID:26216428

Propionibacterium acnes Recovered from Atherosclerotic Human Carotid Arteries Undergoes Biofilm Dispersion and Releases Lipolytic and Proteolytic Enzymes in Response to Norepinephrine Challenge In Vitro.

PubMed

Lanter, Bernard B; Davies, David G

2015-10-01

In the present study, human atherosclerotic carotid arteries were examined following endarterectomy for the presence of the Gram-positive bacterium Propionibacterium acnes and its potential association with biofilm structures within the arterial wall. The P. acnes 16S rRNA gene was detectable in 4 of 15 carotid artery samples, and viable P. acnes was one among 10 different bacterial species recoverable in culture. Fluorescence in situ hybridization analysis of 5 additional atherosclerotic carotid arteries demonstrated biofilm bacteria within all samples, with P. acnes detectable in 4 samples. We also demonstrated that laboratory-grown cultures of P. acnes biofilms were susceptible to induction of a biofilm dispersion response when challenged with physiologically relevant levels of norepinephrine in the presence of iron-bound transferrin or with free iron. The production and release of lipolytic and proteolytic extracellular enzymes by P. acnes were shown to increase in iron-induced dispersed biofilms, and these dispersion-induced P. acnes VP1 biofilms showed increased expression of mRNAs for the triacylglycerol lipases PPA2105 and PPA1796 and the hyaluronate lyase PPA380 compared to that in untreated biofilms. These results demonstrate that P. acnes can infect the carotid arteries of humans with atherosclerosis as a component of multispecies biofilms and that dispersion is inducible for this organism, at least in vitro, with physiologically relevant levels of norepinephrine resulting in the production and release of degradative enzymes. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Proximal protection with hybrid stent, a safer combination for carotid artery stenting against carotid endarterectomy?

PubMed

Gürkaş, E; Ak, F; Orhan, G; Bozkurt, E; Ulusoy, E K

2015-12-01

Carotid revascularization is an established theurapeutic modality in preventing stroke and death among patients with severe carotid stenosis. Although carotid endarterectomy remains as the primary option, carotid stenting is accepted as an alternative for patients with high risk for carotid endarterectomy. Recently published reports have better results with proximal protection devices when compared with distal protection devices. These studies have revealed less microembolic signals and less periprocedural new ischemic lesions on diffusion weighted magnetic resonance imaging. Stent choice may be also important for these procedures as open cell stent design has advantage of better flexibility whereas closed cell systems have an advantage of better scaffolding. Hybrid stents which are composed of open cells in the proximal and distal part and closed cells in the middle may carry both advantages. The aim of this study is to demonstrate whether combination of proximal protection devices with hybrid stents can be a safe alternative for carotid stenting in terms of periprocedural and 30-day outcomes. Here we retrospectively evaluated 68 symptomatic carotid stenosis patients undergoing carotid stenting with hybrid stent (Cristallo Ideale®, Invatec s.r.l., Medtronic, Italy) and proximal protection device (MO.MA®, Invatec s.r.l., Medtronic, Italy). Our results showed only 1 minor stroke in the periprocedural period and during the first 30-day after stenting, with no death or myocardial infarction. Although our case number is not large, we propose that carotid stenting may be safer with utilization of proximal protection system and hybrid type carotid stents.

Correlation of carotid blood flow and corrected carotid flow time with invasive cardiac output measurements.

PubMed

Ma, Irene W Y; Caplin, Joshua D; Azad, Aftab; Wilson, Christina; Fifer, Michael A; Bagchi, Aranya; Liteplo, Andrew S; Noble, Vicki E

2017-12-01

Non-invasive measures that can accurately estimate cardiac output may help identify volume-responsive patients. This study seeks to compare two non-invasive measures (corrected carotid flow time and carotid blood flow) and their correlations with invasive reference measurements of cardiac output. Consenting adult patients (n = 51) at Massachusetts General Hospital cardiac catheterization laboratory undergoing right heart catheterization between February and April 2016 were included. Carotid ultrasound images were obtained concurrently with cardiac output measurements, obtained by the thermodilution method in the absence of severe tricuspid regurgitation and by the Fick oxygen method otherwise. Corrected carotid flow time was calculated as systole time/√cycle time. Carotid blood flow was calculated as π × (carotid diameter) 2 /4 × velocity time integral × heart rate. Measurements were obtained using a single carotid waveform and an average of three carotid waveforms for both measures. Single waveform measurements of corrected flow time did not correlate with cardiac output (ρ = 0.25, 95% CI -0.03 to 0.49, p = 0.08), but an average of three waveforms correlated significantly, although weakly (ρ = 0.29, 95% CI 0.02-0.53, p = 0.046). Carotid blood flow measurements correlated moderately with cardiac output regardless of if single waveform or an average of three waveforms were used: ρ = 0.44, 95% CI 0.18-0.63, p = 0.004, and ρ = 0.41, 95% CI 0.16-0.62, p = 0.004, respectively. Carotid blood flow may be a better marker of cardiac output and less subject to measurements issues than corrected carotid flow time.

Simulations of blood flow through a stenosed carotid artery

NASA Astrophysics Data System (ADS)

Lundin, Staffan; Meder, Samuel; Metcalfe, Ralph

2000-11-01

The human carotid artery is often the site of the formation of atherosclerotic lesions that can lead to severe reduction of blood flow to the brain, frequently resulting in a stroke. There is strong evidence that hemodynamic variables such as the wall shear stress and its spatial and temporal derivatives play a role in fostering atherosclerosis. To investigate the potential of these effects, we have performed unsteady, three-dimensional numerical simulations of blood flow through the carotid bifurcation in the presence of stenoses of varying degrees and eccentricities. The simulations indicate that regions of low maximum and minimum shear stress correlate better with lesion prone sites than low average wall shear stress. As the degree of stenosis increases, it is found that the downstream flow changes drastically for stenoses greater than about 25Downstream eddies are generated during systole that create local shear stress peaks on the internal carotid artery wall, resulting in significant reduction in flow rates through the internal carotid artery. Large secondary flows develop, and there are also periods of flow reversal during the systolic/diastolic cycle.

Glossopharyngeal schwannoma of the suprahyoid carotid space: case report and discussion of the relationship to the carotid artery.

PubMed

Nagamine, Wayde H; Conneely, Mark F; Petruzzelli, Guy J; Hacein-Bey, Lotfi

2009-04-01

The distinction between lesions of the deep parotid space and those of the carotid space has been greatly facilitated by cross-sectional imaging, particularly magnetic resonance imaging (MRI), due to 1) good assessment of parapharyngeal fat displacement, and 2) reliable and consistent identification of the carotid artery. While masticator space masses consistently displace the carotid artery posteriorly, it is generally assumed that carotid space masses, particularly schwannomas, displace the carotid artery anteriorly. We report on a patient with a rare glossopharyngeal schwannoma of the carotid space that caused posterior displacement of the carotid artery. A 38-year-old female presented with headaches and a pharyngeal sensation of a foreign body without dysgeusia and dysphagia. Computed tomography (CT) and MRI showed a left carotid space mass, suggestive of a schwannoma, although the internal carotid artery was displaced posteriorly. The mass was hypovascular at angiography. The patient underwent surgical excision of her lesion via a left cervical-parotid approach. In our patient with a carotid space mass, all imaging features suggested a schwannoma, except for posterior displacement of the carotid artery. A glossopharyngeal nerve schwannoma was found at surgery. Schwannomas of the glossopharyngeal nerve are uncommon, and those originating from the extracranial course of the nerve are extremely rare. Schwannomas of the suprahyoid carotid space most commonly arise from the vagus nerve and have a typical pattern, which includes anterior displacement of the carotid artery. A rare exception to this has been reported in schwannomas of the sympathetic nerve, which may displace the carotid artery posteromedially. Our patient had a schwannoma of the extracranial glossopharyngeal nerve, which caused posterolateral carotid displacement.

Hepatitis C virus eradication by direct-acting antiviral agents improves carotid atherosclerosis in patients with severe liver fibrosis.

PubMed

Petta, Salvatore; Adinolfi, Luigi Elio; Fracanzani, Anna Ludovica; Rini, Francesca; Caldarella, Rosalia; Calvaruso, Vincenza; Cammà, Calogero; Ciaccio, Marcello; Di Marco, Vito; Grimaudo, Stefania; Licata, Anna; Marrone, Aldo; Nevola, Riccardo; Pipitone, Rosaria Maria; Pinto, Antonio; Rinaldi, Luca; Torres, Daniele; Tuttolomondo, Antonino; Valenti, Luca; Fargion, Silvia; Craxì, Antonio

2018-07-01

Recent studies suggest an association between hepatitis C virus (HCV) infection and cardiovascular damage, including carotid atherosclerosis, with a possible effect of HCV clearance on cardiovascular outcomes. We aimed to examine whether HCV eradication by direct-acting antiviral agents (DAA) improves carotid atherosclerosis in HCV-infected patients with advanced fibrosis/compensated cirrhosis. One hundred eighty-two consecutive patients with HCV and advanced fibrosis or compensated cirrhosis were evaluated. All patients underwent DAA-based antiviral therapy according to AISF/EASL guidelines. Intima-media thickness (IMT), carotid thickening (IMT ≥1 mm) and carotid plaques, defined as focal thickening of ≥1.5 mm at the level of the common carotid, were evaluated by ultrasonography (US) at baseline and 9-12 months after the end of therapy. Fifty-six percent of patients were male, mean age 63.1 ± 10.4 years, and 65.9% had compensated cirrhosis. One in five had diabetes, 14.3% were obese, 41.8% had arterial hypertension and 35.2% were smokers. At baseline, mean IMT was 0.94 ± 0.29 mm, 42.8% had IMT ≥1 mm, and 42.8% had carotid plaques. All patients achieved a 12-week sustained virological response. IMT significantly decreased from baseline to follow-up (0.94 ± 0.29 mm vs. 0.81 ± 0.27, p <0.001). Consistently, a significant reduction in the prevalence of patients with carotid thickening from baseline to follow-up was observed (42.8% vs. 17%, p <0.001), while no changes were reported for carotid plaques (42.8% vs. 47.8%, p = 0.34). These results were confirmed in subgroups of patients stratified for cardiovascular risk factors and liver disease severity. HCV eradication by DAA improves carotid atherosclerosis in patients with severe fibrosis with or without additional metabolic risk factors. The impact of this improvement in the atherosclerotic burden in terms of reduction of major cardiovascular outcomes is worth

Safety Outcomes Using a Proximal Protection Device in Carotid Stenting of Long Carotid Stenoses

PubMed Central

Atchaneeyasakul, Kunakorn; Khandelwal, Priyank; Ambekar, Sudheer; Ramdas, Kevin; Guada, Luis; Yavagal, Dileep

2016-01-01

Background Embolic protection devices can prevent atherosclerotic emboli during carotid stenting. Newer proximal protection devices reverse flow in the internal carotid artery (ICA), leading to reduction in perioperative microemboli. The risk of stroke is high for carotid stenting of ICA lesions with a length >10 mm and/or angiographic string sign. Objective We aimed to evaluate the safety outcomes of proximal embolic protection device usage in this high-risk group. Methods This is a retrospective analysis of patients who underwent carotid stenting procedures with proximal embolic protection devices at a tertiary care center. High-risk features for adverse events with carotid stenting were identified. Peri- and postprocedural outcomes were recorded. We further compared outcomes in patients with a carotid stenosis length >10 mm to those with shorter stenosis. Results From January 2011 to December 2014, we included 27 patients; 96.3% were symptomatic and 3.7% were asymptomatic. There was a stent placement technical success rate of 100%. No major stroke or coronary events were recorded. One minor stroke event developed in one patient. A carotid lesion length >10 mm and/or angiographic string sign was noted in 21/27 patients, with an average lesion length of 14.4 mm. One patient (4.8%) in this group developed a minor stroke event. Neither a coronary nor a major stroke event was recorded in this group. There was no significant difference in the complication rate between the long lesion and the control group. Conclusion In our patient cohort, it was found that a proximal embolic protection device is safe for patients with carotid stenosis, including those with a carotid lesion length >10 mm and/or angiographic string sign. PMID:27781040

Cerebral infarction caused by traumatic carotid artery dissection.

PubMed

Bayır, Ayşegül; Aydoğdu Kıreşi, Demet; Söylemez, Ali; Demirci, Osman

2012-07-01

Traumatic carotid artery dissection, if not diagnosed and treated early, is a serious problem with permanent neurological deficit and a high mortality rate of up to 40%. We present a case with delayed diagnosis of traumatic carotid artery dissection in a 21-year-old female. While there were no ischemic infarct findings on the admission cerebral computerized tomography (CT), such findings were observed on two cerebral CTs taken because of the left hemiplegia noticed seven days later when the patient regained consciousness. The patient was referred to our emergency service, and definitive diagnosis was achieved with arterial Doppler ultrasonography, cerebral magnetic resonance imaging (MRI), diffusion MRI, and MR angiography. We did not consider invasive treatment since the neurological damage was permanent and dissection grade was IV according to angiography findings. The case was discharged within a week and physiotherapy was advised. Despite the advances in diagnostic methods, diagnosis of traumatic carotid artery dissection is still missed or delayed, as in the case presented here. Early diagnosis can ameliorate permanent neurological damage or even prevent it. However, the vital factors for early diagnosis are the obtained anamnesis leading to appropriate radiological examinations, detailed physical examination and high clinical suspicion.

Effective Intraluminal Shunt in Carotid Endarterectomy for Carotid Artery Near Occlusion: Technical Report.

PubMed

Kawamura, Yoichiro; Maruyama, Daisuke; Akagi, Yojiro; Iihara, Koji

2017-10-01

Carotid artery near occlusion is a critical degree of stenosis whereby blood flow is decreased and the distal cervical and intracranial internal carotid arteries (ICAs) are prone to collapse. Considering the diminished perfusion and risk of progression to total occlusion and periocclusive embolism, we performed carotid endarterectomy for carotid artery near occlusion. Accurate evaluation of tandem stenosis or patency of the poststenotic ICA in carotid artery near occlusion is often difficult preoperatively. Thus we performed carotid endarterectomy in a hybrid operating room where intraoperative digital subtraction angiography (DSA) and endovascular angioplasty or stenting for distal lesions can be performed if necessary. In addition, to evaluate the distal ICA intraoperatively, we used an intraluminal shunt for shunt angiography, with injection of contrast material through the shunt tube, as a replacement for conventional DSA. Furthermore, an intraluminal shunt held the collapsed lumen open and provided a scaffold for suturing, which prevented postoperative stenosis of the distal ICA. The present report is intended to underline the merits of intraluminal shunt as a replacement for conventional DSA and as a scaffold for suturing. Copyright © 2017 Elsevier Inc. All rights reserved.

Successful Resection of a Large Carotid Body Tumor Masquerading Complete Encasement of the Internal Carotid Artery on Preoperative Imaging.

PubMed

Kakkos, Stavros K; Zampakis, Peter; Lampropoulos, George C; Paridis, Leonidas; Kaplanis, Charalampos; Bantouna, Dimitra; Nikolakopoulos, Konstantinos M; Papageorgopoulou, Chrysanthi P; Kalogeropoulou, Christina; Tsolakis, Ioannis A

2018-05-01

A 41-year-old woman presented with a large painful and tender mass of the left side of her neck located just below the angle of the mandible. She was also complaining of frequent attacks of symptoms ranging from dizziness upon resuming the erect position to frank syncope. Color-coded duplex showed a large well-vascularized vascular mass at the level of the carotid bifurcation, suggesting the diagnosis of a carotid body tumor (CBT). A computerized tomographic angiography confirmed the diagnosis of a CBT, which measured 5.7 cm in its craniocaudal axis. The tumor appeared to encase the internal carotid artery (ICA) at the level of its origin, indicating the presence of a Shamblin group 3 tumor. During surgery, the CBT seemingly encased the ICA; however, it was successfully taken off the ICA, by establishing an adventitial dissection place, obviating the need for arterial resection and replacement. A brief intraoperative episode of cardiac arrest was successfully managed. Postoperative course was uneventful, and all symptoms were cured. Pathology confirmed the clinical diagnosis and did not show malignancy. In conclusion, meticulous surgical techniques can spare the ICA from removal or inadvertent injury during CBT surgery and reduce the morbidity often associated with the resection of large or advanced tumors but also cure atypical patient symptoms.

Bilateral Internal Carotid Artery Occlusion, External Carotid Artery Stenosis, and Vertebral Artery Kinking: May It Be Asymptomatic?

PubMed

Fatic, Nikola; Jaffer, Usman; Ivana, Saicic; Gordana, Globarevic-Vukcevic; Markovic, Dragan; Kostic, Dusan; Davidovic, Lazar

2017-10-01

The clinical spectrum of internal carotid artery occlusion ranges from being a completely asymptomatic occlusion to a devastating stroke or death. The prevalence of asymptomatic internal carotid artery occlusion is unknown, particularly for bilateral occlusion. The distal branches of the external carotid artery anastomose with distal branches of the internal carotid artery provide important sources of collateral circulation to the brain. Stenosis of the external carotid artery with ipsilateral/bilateral internal occlusion may result in ischemic sequelae. Coiling or kinking of the vertebral artery is a rare morphological entity that is infrequently reported because it remains asymptomatic and has no clinical relevance. Currently, there is little evidence to support management strategies for this disease entity and no official recommendations for asymptomatic bilateral carotid artery occlusion. We present a case of a 62-year-old female with asymptomatic bilateral internal carotid artery occlusion, bilateral external carotid artery stenoses, and bilateral kinking of the vertebral artery at the V2 segment, who has been successfully managed conservatively for over 5 years. An individualized approach to management of patients with bilateral internal carotid artery occlusion, especially in combination with external carotid artery stenosis and elongation malformations of the vertebral artery is key to a successful strategy. Copyright © 2017 Elsevier Inc. All rights reserved.

Management of Carotid Artery Trauma

PubMed Central

Lee, Thomas S.; Ducic, Yadranko; Gordin, Eli; Stroman, David

2014-01-01

With increased awareness and liberal screening of trauma patients with identified risk factors, recent case series demonstrate improved early diagnosis of carotid artery trauma before they become problematio. There remains a need for unified screening criteria for both intracranial and extracranial carotid trauma. In the absence of contraindications, antithrombotic agents should be considered in blunt carotid artery injuries, as there is a significant risk of progression of vessel injury with observation alone. Despite CTA being used as a common screening modality, it appears to lack sufficient sensitivity. DSA remains to be the gold standard in screening. Endovascular techniques are becoming more widely accepted as the primary surgical modality in the treatment of blunt extracranial carotid injuries and penetrating/blunt intracranial carotid lessions. Nonetheless, open surgical approaches are still needed for the treatment of penetrating extracranial carotid injuries and in patients with unfavorable lesions for endovascular intervention. PMID:25136406

Carotid revascularization: risks and benefits

PubMed Central

O’Brien, Marlene; Chandra, Ankur

2014-01-01

Despite a decline during the recent decades in stroke-related death, the incidence of stroke has remained unchanged or slightly increased, and extracranial carotid artery stenosis is implicated in 20%–30% of all strokes. Medical therapy and risk factor modification are first-line therapies for all patients with carotid occlusive disease. Evidence for the treatment of patients with symptomatic carotid stenosis greater than 70% with either carotid artery stenting (CAS) or carotid endarterectomy (CEA) is compelling, and several trials have demonstrated a benefit to carotid revascularization in the symptomatic patient population. Asymptomatic carotid stenosis is more controversial, with the largest trials only demonstrating a 1% per year risk stroke reduction with CEA. Although there are sufficient data to advocate for aggressive medical therapy as the primary mode of treatment for asymptomatic carotid stenosis, there are also data to suggest that certain patient populations will benefit from a stroke risk reduction with carotid revascularization. In the United States, consensus and practice guidelines dictate that CEA is reasonable in patients with high-grade asymptomatic stenosis, a reasonable life expectancy, and perioperative risk of less than 3%. Regarding CAS versus CEA, the best-available evidence demonstrates no difference between the two procedures in early perioperative stroke, myocardial infarction, or death, and no difference in 4-year ipsilateral stroke risk. However, because of the higher perioperative risks of stroke in patients undergoing CAS, particularly in symptomatic, female, or elderly patients, it is difficult to recommend CAS over CEA except in populations with prohibitive cardiac risk, previous carotid surgery, or prior neck radiation. Current treatment paradigms are based on identifying the magnitude of perioperative risk in patient subsets and on using predictive factors to stratify patients with high-risk asymptomatic stenosis. PMID

Screening for Carotid Artery Stenosis

MedlinePlus

... build up and harden the arteries, limiting the flow of blood to the brain. Facts About Carotid Artery Stenosis Carotid artery stenosis is one of many risk factors for stroke, a leading cause of death and disability in the United States. However, carotid artery stenosis is uncommon—about ½ ...

The relationship between carotid blood pressure reactivity to mental stress and carotid intima-media thickness.

PubMed

Spartano, Nicole L; Augustine, Jacqueline A; Lefferts, Wesley K; Gump, Brooks B; Heffernan, Kevin S

2014-10-01

Brachial blood pressure (BP) reactivity to stress predicts large artery damage and future cardiovascular (CV) events. Central BP is an emerging risk factor associated with target organ damage (TOD). Currently, little is known about the central BP response to mental stress and its association to TOD. Twenty-five healthy, non-obese adults completed a computerized mental stress test. Brachial and carotid systolic (S)BP reactivity to stress were calculated as SBP during stress minus resting SBP. Resting carotid intima-media thickness (IMT) was also measured. Carotid SBP reactivity to stress was significantly associated with carotid IMT, independent of age, sex, body mass index, non-high density lipoprotein cholesterol and brachial SBP reactivity to stress (r = 0.386, p < 0.05). The relationship between carotid SBP reactivity and carotid IMT suggests that the central BP response to stress may prove to be an early risk marker for potential subclinical TOD. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Characterising human atherosclerotic carotid plaque tissue composition and morphology using combined spectroscopic and imaging modalities.

PubMed

Barrett, Hilary E; Mulvihill, John J; Cunnane, Eoghan M; Walsh, Michael T

2015-01-01

Calcification is a marked pathological component in carotid artery plaque. Studies have suggested that calcification may induce regions of high stress concentrations therefore increasing the potential for rupture. However, the mechanical behaviour of the plaque under the influence of calcification is not fully understood. A method of accurately characterising the calcification coupled with the associated mechanical plaque properties is needed to better understand the impact of calcification on the mechanical behaviour of the plaque during minimally invasive treatments. This study proposes a comparison of biochemical and structural characterisation methods of the calcification in carotid plaque specimens to identify plaque mechanical behaviour. Biochemical analysis, by Fourier Transform Infrared (FTIR) spectroscopy, was used to identify the key components, including calcification, in each plaque sample. However, FTIR has a finite penetration depth which may limit the accuracy of the calcification measurement. Therefore, this FTIR analysis was coupled with the identification of the calcification inclusions located internally in the plaque specimen using micro x-ray computed tomography (μX-CT) which measures the calcification volume fraction (CVF) to total tissue content. The tissue characterisation processes were then applied to the mechanical material plaque properties acquired from experimental circumferential loading of human carotid plaque specimen for comparison of the methods. FTIR characterised the degree of plaque progression by identifying the functional groups associated with lipid, collagen and calcification in each specimen. This identified a negative relationship between stiffness and 'lipid to collagen' and 'calcification to collagen' ratios. However, μX-CT results suggest that CVF measurements relate to overall mechanical stiffness, while peak circumferential strength values may be dependent on specific calcification geometries. This study

Factor analytic reduction of the carotid-cardiac baroreflex parameters

NASA Technical Reports Server (NTRS)

Ludwig, David A.

1989-01-01

An accepted method for measuring the responsiveness of the carotid-cardiac baroreflex to arterial pressure changes is to artificially stimulate the baroreceptors in the neck. This is accomplished by using a pressurized neck cuff which constricts and distends the carotid artery and subsequently stimulates the baroreceptors. Nine physiological responses to this type of stimulation are quantified and used as indicators of the baroreflex. Thirty male humans between the ages 27 and 46 underwent the carotid-cardiac baroreflex test. The data for the nine response parameters were analyzed by principle component factor analysis. The results of this analysis indicated that 93 percent of the total variance across all nine parameters could be explained in four dimensions. Examination of the factor loadings following an orthogonal rotation of the principle components indicated four well defined dimensions. The first two dimensions reflected location points for R-R interval and carotid distending pressure respectively. The third dimension was composed of measures reflecting the gain of the reflex. The fourth dimension was the ratio of the resting R-R interval to R-R interval during simulated hypertension. The data suggests that the analysis of all nine baroreflex parameters is redundant.

MR coil sensitivity inhomogeneity correction for plaque characterization in carotid arteries

NASA Astrophysics Data System (ADS)

Salvado, Olivier; Hillenbrand, Claudia; Suri, Jasjit; Wilson, David L.

2004-05-01

We are involved in a comprehensive program to characterize atherosclerotic disease using multiple MR images having different contrast mechanisms (T1W, T2W, PDW, magnetization transfer, etc.) of human carotid and animal model arteries. We use specially designed intravascular and surface array coils that give high signal-to-noise but suffer from sensitivity inhomogeneity. With carotid surface coils, challenges include: (1) a steep bias field with an 80% change; (2) presence of nearby muscular structures lacking high frequency information to distinguish bias from anatomical features; (3) many confounding zero-valued voxels subject to fat suppression, blood flow cancellation, or air, which are not subject to coil sensitivity; and (4) substantial noise. Bias was corrected using a modification of the adaptive fuzzy c-mean method reported by Pham et al. (IEEE TMI, 18:738-752), whereby a bias field modeled as a mechanical membrane was iteratively improved until cluster means no longer changed. Because our images were noisy, we added a noise reduction filtering step between iterations and used about 5 classes. In a digital phantom having a bias field measured from our MR system, variations across an area comparable to a carotid artery were reduced from 50% to <5% with processing. Human carotid images were qualitatively improved and large regions of skeletal muscle were relatively flat. Other commonly applied techniques failed to segment the images or introduced strong edge artifacts. Current evaluations include comparisons to bias as measured by a body coil in human MR images.

Carotid Artery Stenting and Blood-Brain Barrier Permeability in Subjects with Chronic Carotid Artery Stenosis.

PubMed

Szarmach, Arkadiusz; Halena, Grzegorz; Kaszubowski, Mariusz; Piskunowicz, Maciej; Studniarek, Michal; Lass, Piotr; Szurowska, Edyta; Winklewski, Pawel J

2017-05-08

Failure of the blood-brain barrier (BBB) is a critical event in the development and progression of diseases such as acute ischemic stroke, chronic ischemia or small vessels disease that affect the central nervous system. It is not known whether BBB breakdown in subjects with chronic carotid artery stenosis can be restrained with postoperative recovery of cerebral perfusion. The aim of the study was to assess the short-term effect of internal carotid artery stenting on basic perfusion parameters and permeability surface area-product (PS) in such a population. Forty subjects (23 males) with stenosis of >70% within a single internal carotid artery and neurological symptoms who underwent a carotid artery stenting procedure were investigated. Differences in the following computed tomography perfusion (CTP) parameters were compared before and after surgery: global cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP) and PS. PS acquired by CTP is used to measure the permeability of the BBB to contrast material. In all baseline cases, the CBF and CBV values were low, while MTT and TTP were high on both the ipsi- and contralateral sides compared to reference values. PS was approximately twice the normal value. CBF was higher (+6.14%), while MTT was lower (-9.34%) on the contralateral than on the ipsilateral side. All perfusion parameters improved after stenting on both the ipsilateral (CBF +22.66%; CBV +18.98%; MTT -16.09%, TTP -7.62%) and contralateral (CBF +22.27%, CBV +19.72%, MTT -14.65%, TTP -7.46%) sides. PS decreased by almost half: ipsilateral -48.11%, contralateral -45.19%. The decline in BBB permeability was symmetrical on the ipsi- and contralateral sides to the stenosis. Augmented BBB permeability can be controlled by surgical intervention in humans.

Increased Expression of Interleukin-18 mRNA is Associated with Carotid Artery Stenosis

PubMed

Arapi, Berk; Bayoğlu, Burcu; Cengiz, Müjgan; Dirican, Ahmet; Deser, Serkan Burç; Junusbekov, Yerik; Arslan, Caner

2018-05-29

Carotid artery stenosis is the atherosclerotic narrowing of the proximal internal carotid artery and one of the primary causes of stroke. Elevated expression of the pleiotropic proinflammatory cytokine interleukin-18 has been demonstrated in human atherosclerotic plaques. To investigate whether the mRNA expression levels of interleukin-18 and interleukin-18-binding protein and interleukin-18 −137 G/C (rs187238) variants are associated with carotid artery stenosis development. Case-control study. The mRNA expression levels of interleukin-18 and interleukin-18-binding protein and interleukin-18 rs187238 variants were evaluated by quantitative real-time polymerase chain reaction and real-time polymerase chain reaction, respectively, in the peripheral blood mononuclear cells of 70 patients with carotid artery stenosis (36 symptomatic, 34 asymptomatic) and 75 healthy controls. Interleukin-18 mRNA expression was significantly increased in carotid artery stenosis patients compared to that in healthy controls (p=0.01). However, no significant difference was observed between interleukin-18-binding protein mRNA expression levels in patients with carotid artery stenosis and those in controls (p=0.101). Internal carotid artery stenosis severity was significantly higher in symptomatic patients than that in asymptomatic patients (p<0.001). A significant relationship was identified between interleukin-18 expression and internal carotid artery stenosis severity in patients with carotid artery stenosis (p=0.051). Interleukin-18 rs187238 polymorphism genotype frequencies did not significantly differ between patients with carotid artery stenosis and controls (p=0.246). A significant difference was identified between interleukin-18-binding protein gene expression and symptomatic and asymptomatic patients (p=0.026), but there was no difference in interleukin-18 expression between the symptomatic and asymptomatic subgroups (p=0.397). Interleukin-18 mRNA expression may affect carotid

Angioplasty and stent placement - carotid artery

MedlinePlus

... medlineplus.gov/ency/article/002953.htm Angioplasty and stent placement - carotid artery To use the sharing features ... to remove plaque buildup ( endarterectomy ) Carotid angioplasty with stent placement Description Carotid angioplasty and stenting (CAS) is ...

[Risk factors of rupture of internal carotid artery during surgical resection of carotid body tumor].

PubMed

Li, Y H; Wang, J S; Yao, C; Chang, G Q; Yin, H H; Li, S Q; Lü, W M; Hu, Z J; Wang, S M

2017-06-13

Objective: To investigate risk factors of rupture of internal carotid artery resection during carotid body tumor resection and to summarize our treatment experience. Methods: During the period from 1991 to 2016, rupture of internal carotid artery occurred in 27 patients (28 tumors) during surgical resection of carotid body tumor in the First Affiliated Hospital of Sun Yat-sen University. Their clinical and follow-up data were retrospectively collected and analyzed. For all patients underwent surgical resection during this period, Logistic regression analysis was used to investigate the risk factors of intraoperative rupture of internal carotid artery. Results: Of these 28 tumors, there were 15 (53.6%) tumors with diameter≥5 cm and 20 (71.4%) Shamblin Ⅲ tumors. Intraoperatively, shunt was applied for 8 (28.6%) cases. Thirteen (46.4%) patients underwent ligation of external carotid artery, while 2 (7.1%) patients accepted resection of cranial nerves. Direct closure/patchplasty, autologous vessels or graft reconstruction was used in 16, 10 and 2 cases, respectively. Postoperatively, stroke occurred in 4(14.3%) cases and cranial nerve deficit in 15 (53.6%) cases. During a median length of 36 (14-125) months, cranial nerve deficit persisted in 5 cases. Follow-up radiologic examination indicated 3 (10.7%) cases of targeted vessel occlusion. However, no new-onset stroke was identified. Among all patients underwent surgical resection of carotid body tumor, female ( OR =3.650, P =0.012), age≤25 years old ( OR =3.710, P =0.013) and Shamblin Ⅲ tumor ( OR =4.631, P =0.008) increase the risks of intraoperative carotid artery rupture. Conclusions: Shamblin Ⅲ tumor is the predictor of rupture of internal carotid artery. Intraoperative, properly increased blood pressure, intraoperative heparinization and use of shunt for those cases without well-compensated cranial collateral arteries are likely to decreasing the incidence of stroke.

Carotid Disease Management: Surgery, Stenting, or Medication.

PubMed

Khandelwal, Priyank; Chaturvedi, Seemant

2015-09-01

Internal carotid artery stenosis accounts for about 7-10 % of ischemic strokes. Conventional risk factors such as aging, hypertension, diabetes mellitus, and smoking increase the risk for carotid atherosclerosis. All patients with carotid stenosis should receive aggressive medical therapy. Carotid revascularization with either endarterectomy or stenting can benefit select patients with severe stenosis. New clinical trials will examine the contemporary role of carotid revascularization relative to optimal medical therapy.

Role of central command in carotid baroreflex resetting in humans during static exercise

NASA Technical Reports Server (NTRS)

Ogoh, S.; Wasmund, W. L.; Keller, D. M.; O-Yurvati, A.; Gallagher, K. M.; Mitchell, J. H.; Raven, P. B.

2002-01-01

The purpose of the experiments was to examine the role of central command in the exercise-induced resetting of the carotid baroreflex. Eight subjects performed 30 % maximal voluntary contraction (MVC) static knee extension and flexion with manipulation of central command (CC) by patellar tendon vibration (PTV). The same subjects also performed static knee extension and flexion exercise without PTV at a force development that elicited the same ratings of perceived exertion (RPE) as those observed during exercise with PTV in order to assess involvement of the exercise pressor reflex. Carotid baroreflex (CBR) function curves were modelled from the heart rate (HR) and mean arterial pressure (MAP) responses to rapid changes in neck pressure and suction during steady state static exercise. Knee extension exercise with PTV (decreased CC activation) reset the CBR-HR and CBR-MAP to a lower operating pressure (P < 0.05) and knee flexion exercise with PTV (increased CC activation) reset the CBR-HR and CBR-MAP to a higher operating pressure (P < 0.05). Comparison between knee extension and flexion exercise at the same RPE with and without PTV found no difference in the resetting of the CBR-HR function curves (P > 0.05) suggesting the response was determined primarily by CC activation. However, the CBR-MAP function curves were reset to operating pressures determined by both exercise pressor reflex (EPR) and central command activation. Thus the physiological response to exercise requires CC activation to reset the carotid-cardiac reflex but requires either CC or EPR to reset the carotid-vasomotor reflex.

Flow diversion in the treatment of carotid injury and carotid-cavernous fistula after transsphenoidal surgery

PubMed Central

Lum, Cheemum; Ahmed, Muhammad E; Glikstein, Rafael; dos Santos, Marlise P; Lesiuk, Howard; Labib, Mohamed; Kassam, Amin B

2015-01-01

We describe a case of iatrogenic carotid injury with secondary carotid-cavernous fistula (CCF) treated with a silk flow diverter stent placed within the injured internal carotid artery and coils placed within the cavernous sinus. Flow diverters may offer a simple and potentially safe vessel-sparing option in this rare complication of transsphenoidal surgery. The management options are discussed and the relevant literature is reviewed. PMID:26015526

When is carotid angioplasty and stenting the cost-effective alternative for revascularization of symptomatic carotid stenosis? A Canadian health system perspective.

PubMed

Almekhlafi, M A; Hill, M D; Wiebe, S; Goyal, M; Yavin, D; Wong, J H; Clement, F M

2014-02-01

Carotid revascularization procedures can be complicated by stroke. Additional disability adds to the already high costs of the procedure. To weigh the cost and benefit, we estimated the cost-utility of carotid angioplasty and stenting compared with carotid endarterectomy among patients with symptomatic carotid stenosis, with special emphasis on scenario analyses that would yield carotid angioplasty and stenting as the cost-effective alternative relative to carotid endarterectomy. A cost-utility analysis from the perspective of the health system payer was performed by using a Markov analytic model. Clinical estimates were based on a meta-analysis. The procedural costs were derived from a microcosting data base. The costs for hospitalization and rehabilitation of patients with stroke were based on a Canadian multicenter study. Utilities were based on a randomized controlled trial. In the base case analysis, carotid angioplasty and stenting were more expensive (incremental cost of $6107) and had a lower utility (-0.12 quality-adjusted life years) than carotid endarterectomy. The results are sensitive to changes in the risk of clinical events and the relative risk of death and stroke. Carotid angioplasty and stenting were more economically attractive among high-risk surgical patients. For carotid angioplasty and stenting to become the preferred option, their costs would need to fall from more than $7300 to $4350 or less and the risks of the periprocedural and annual minor strokes would have to be equivalent to that of carotid endarterectomy. In the base case analysis, carotid angioplasty and stenting were associated with higher costs and lower utility compared with carotid endarterectomy for patients with symptomatic carotid stenosis. Carotid angioplasty and stenting were cost-effective for patients with high surgical risk.

Contrast-enhanced ultrasonography vs B-mode ultrasound for visualization of intima-media thickness and detection of plaques in human carotid arteries.

PubMed

Shah, Benoy N; Chahal, Navtej S; Kooner, Jaspal S; Senior, Roxy

2017-05-01

Carotid intima-media thickness (IMT) and plaque are recognized markers of increased risk for cerebrovascular events. Accurate visualization of the IMT and plaques is dependent upon image quality. Ultrasound contrast agents improve image quality during echocardiography-this study assessed whether contrast-enhanced ultrasound (CEUS) improves carotid IMT visualization and plaque detection in an asymptomatic population. Individuals free from known cardiovascular disease, enrolled in a community study, underwent B-mode and CEUS carotid imaging. Each carotid artery was divided into 10 segments (far and near walls of the proximal, mid and distal segments of the common carotid artery, the carotid bulb, and internal carotid artery). Visualization of the IMT complex and plaque assessments was made during both B-mode and CEUS imaging for all enrolled subjects, a total of 175 individuals (mean age 65±9 years). Visualization of the IMT was significantly improved during CEUS compared with B-mode imaging, in both near and far walls of the carotid arteries (% IMT visualization during B-mode vs CEUS imaging: 61% vs 94% and 66% vs 95% for right and left carotid arteries, respectively, P<.001 for both). Additionally, a greater number of plaques were detected during CEUS imaging compared with B-mode imaging (367 plaques vs 350 plaques, P=.02). Contrast-enhanced ultrasound improves visualization of the intima-media complex, in both near and far walls, of the common and internal carotid arteries and permits greater detection of carotid plaques. Further studies are required to determine whether there is incremental clinical and prognostic benefit related to superior plaque detection by CEUS. © 2017, Wiley Periodicals, Inc.

Symptomatic Post Endarterectomy Common Carotid Artery Pseudoaneurysm Treated with Combination of Flow Diverter Implantation and Carotid Stenting

PubMed Central

Imbarrato, Greg; Gordhan, Ajeet

2018-01-01

A 74-year-old male developed cervical carotid artery psuedoaneurysm 8 months after carotid endarterectomy. The patient was successfully managed with dual implantation of flow-diverter and conventional carotid stent. Flow-diverter was placed across the neck of pseudoaneurysm to provide flow diversion while carotid stent was implanted within the lumen of the expanded flow-diverter to approximate and hold the flow diverter proximal and distal to the pseudoaneurysm. Follow-up ultrasonography revealed complete resolution of the pseudoaneurysm. PMID:29535899

Intra-plaque production of platelet-activating factor correlates with neoangiogenesis in human carotid atherosclerotic lesions.

PubMed

Lupia, Enrico; Pucci, Angela; Peasso, Paolo; Merlo, Maurizio; Baron, Paolo; Zanini, Cristina; Del Sorbo, Lorenzo; Rizea-Savu, Simona; Silvestro, Luigi; Forni, Marco; Emanuelli, Giorgio; Camussi, Giovanni; Montrucchio, Giuseppe

2003-09-01

Platelet-activating factor (PAF) is a phospholipid mediator synthesized by activated inflammatory and endothelial cells. Recently PAF has been shown to contribute to neoangiogenesis in several experimental models. Here we evaluated the presence of PAF and its potential role in neovascularization within human atherosclerotic plaques. The amount of PAF extracted from 18 carotid plaques (266.65+/-40.07 pg/100 mg dry tissue; mean +/- SE) was significantly higher than that extracted from 18 normal arterial specimens (6 from carotid artery and 12 from aorta) (4.72+/-2.31 pg/100 mg dry tissue; mean +/- SE). The levels of PAF significantly correlated with the infiltration of CD68-positive monocytes and the extent of neovascularization, detected as von Willebrand Factor-positive cells. The amount of PAF also correlated with the area occupied by TNF-alpha-expressing cells. The absence of enhanced level of PAF in the circulation of atherosclerotic patients suggests a local production of this mediator within the plaque. The lipid extracts of atherosclerotic plaques containing high levels of PAF-bioactivity, but not those of control arteries, were angiogenic in a murine Matrigel model. WEB 2170, a specific PAF receptor antagonist, significantly prevented angiogenesis induced by the lipid extracts of atherosclerotic plaques. Our results indicate a local production of PAF within the atherosclerotic plaques and suggest that it may contribute to intra-plaque neoangiogenesis.

Carotid Artery Stenting: Single-Center Experience Over 11 Years

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nolz, Richard, E-mail: richard.nolz@meduniwien.ac.at; Schernthaner, Ruediger Egbert, E-mail: ruediger.schernthaner@meduniwien.ac.a; Cejna, Manfred, E-mail: manfred.cejna@lkhf.a

2010-04-15

This article reports the results of carotid artery stenting during an 11-year period. Data from 168 carotid artery stenting procedures (symptomatic, n = 55; asymptomatic, n = 101; symptoms not accessible, n = 12) were retrospectively collected. Primary technical success rate, neurological events in-hospital, access-site complications, and contrast-induced nephropathy (n = 118) were evaluated. To evaluate the influence of experience in carotid artery stenting on intraprocedural neurologic complications, patients were divided into two groups. Group 1 included the first 80 treated patients, and group 2 the remainder of the patients (n = 88). In-stent restenoses at last-follow-up examinations (n =more » 89) were assessed. The overall primary technical success rate was 95.8%. The in-hospital stroke-death rate was 3.0% (n = 5; symptomatic, 5.4%; asymptomatic, 2.0%; p = 0.346). Neurologic complications were markedly higher in group 1 (4.2%; three major strokes; symptomatic, 2.8%, asymptomatic, 1.4%) compared to group 2 (2.4%; one major and one minor stroke-symptomatic, 1.2%, asymptomatic 1.2%), but this was not statistically significant. Further complications were access-site complications in 12 (7.1%), with surgical revision required in 1 (0.6%) and mild contrast-induced nephropathy in 1 (0.85%). Twenty-one (23.6%) patients had >50% in-stent restenosis during a mean follow-up of 28.2 months. In conclusion, advanced experience in carotid artery stenting leads to an acceptable periprocedural stroke-death rate. In-stent restenosis could be a critical factor during the follow-up course.« less

Diagnosis of carotid sinus hypersensitivity in older adults: carotid sinus massage in the upright position is essential

PubMed Central

Parry, S; Richardson, D; O'Shea, D; Sen, B; Kenny, R

2000-01-01

OBJECTIVE—To assess the diagnostic value of supine and upright carotid sinus massage in elderly patients.
DESIGN—Prospective controlled cohort study.
SETTING—Three inner city accident and emergency departments and a dedicated syncope facility.
PATIENTS—1375 consecutive patients aged > 55 years presenting with unexplained syncope and drop attacks; 25 healthy controls.
INTERVENTIONS—Bilateral supine carotid sinus massage, repeated in the 70° head up tilt position if the initial supine test was not diagnostic of cardioinhibitory and mixed carotid sinus hypersensitivity.
MAIN OUTCOME MEASURES—Diagnosis of cardioinhibitory or mixed carotid sinus hypersensitivity; clinical characteristics of supine v upright positive groups.
RESULTS—226 patients were excluded for contraindications to carotid sinus massage. Of 1149 patients undergoing massage, 223 (19%) had cardioinhibitory or mixed carotid sinus hypersensitivity; 70 (31%) of these had a positive response to massage with head up tilt following negative supine massage (95% confidence interval, 25.3% to 37.5%). None of the healthy controls showed carotid sinus hypersensitivity on erect or supine massage. The initially positive supine test had 74% specificity and 100% sensitivity; these were both 100% for the upright positive test. The clinical characteristics of the supine v upright positive subgroups were similar.
CONCLUSIONS—The diagnosis of carotid sinus hypersensitivity amenable to treatment by pacing may be missed in one third of cases if only supine massage is performed. Massage should be done routinely in the head up tilt position if the initial supine test is negative.


Keywords: carotid sinus; tilt table testing; syncope; elderly patients PMID:10618329

[Severe asymptomatic carotid stenosis: a neurological perspective].

PubMed

de la Cruz-Cosme, Carlos; Segura, Tomás

2012-09-01

Asymptomatic carotid stenosis is a relatively frequent pathology, although when considering the possibility of managing it surgically, there is still an important amount of disagreement concerning the criteria to be taken into account. This study conducts a broad examination of the condition, from its concept and epidemiology to the studies that triggered the boom in its surgical treatment during the nineties. The research also reviews the tools available for a better selection of cases that could potentially benefit most from surgery, the presence of silent brain lesions, the severity of the stenosis, its progression, the characteristics of the plaque, colaterality and vasoreactivity studies, the detection of micro-emboli, the presence of risk factors independently associated to the symptomatic conversion of the stenosis, and other elements that have recently been reported either clinically or experimentally. Finally, the article outlines the current state of the surgical technique and the advances being made in its pharmacological treatment. This review is not intended to be a set of clinical practice guidelines, but to offer a global integrating overview of the management of high-grade asymptomatic carotid stenosis.

National variation in preoperative imaging, carotid duplex ultrasound criteria, and threshold for surgery for asymptomatic carotid artery stenosis.

PubMed

Arous, Edward J; Simons, Jessica P; Flahive, Julie M; Beck, Adam W; Stone, David H; Hoel, Andrew W; Messina, Louis M; Schanzer, Andres

2015-10-01

Carotid endarterectomy (CEA) for asymptomatic carotid artery stenosis is among the most common procedures performed in the United States. However, consensus is lacking regarding optimal preoperative imaging, carotid duplex ultrasound criteria, and ultimately, the threshold for surgery. We sought to characterize national variation in preoperative imaging, carotid duplex ultrasound criteria, and threshold for surgery for asymptomatic CEA. The Society for Vascular Surgery Vascular Quality Initiative (VQI) database was used to identify all CEA procedures performed for asymptomatic carotid artery stenosis between 2003 and 2014. VQI currently captures 100% of CEA procedures performed at >300 centers by >2000 physicians nationwide. Three analyses were performed to quantify the variation in (1) preoperative imaging, (2) carotid duplex ultrasound criteria, and (3) threshold for surgery. Of 35,695 CEA procedures in 33,488 patients, the study cohort was limited to 19,610 CEA procedures (55%) performed for asymptomatic disease. The preoperative imaging modality used before CEA varied widely, with 57% of patients receiving a single preoperative imaging study (duplex ultrasound imaging, 46%; computed tomography angiography, 7.5%; magnetic resonance angiography, 2.0%; cerebral angiography, 1.3%) and 43% of patients receiving multiple preoperative imaging studies. Of the 16,452 asymptomatic patients (89%) who underwent preoperative duplex ultrasound imaging, there was significant variability between centers in the degree of stenosis (50%-69%, 70%-79%, 80%-99%) designated for a given peak systolic velocity, end diastolic velocity, and internal carotid artery-to-common carotid artery ratio. Although 68% of CEA procedures in asymptomatic patients were performed for an 80% to 99% stenosis, 26% were performed for a 70% to 79% stenosis, and 4.1% were performed for a 50% to 69% stenosis. At the surgeon level, the range in the percentage of CEA procedures performed for a <80% asymptomatic

Establishing an endovascular carotid stent program.

PubMed

Raabe, Rod; Chong, Brian

2004-12-01

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.

Management of carotid stenosis in women

PubMed Central

Brown, Martin M.; Didier, Leys; Howard, Virginia J.; Moore, Wesley S.; Paciaroni, Maurizio; Ringleb, Peter; Rockman, Caron; Caso, Valeria

2013-01-01

Objective: Specific guidelines for management of cerebrovascular risk in women are currently lacking. This study aims to provide a consensus expert opinion to help make clinical decisions in women with carotid stenosis. Methods: Proposals for the use of carotid endarterectomy (CEA), carotid stenting (CAS), and medical therapy for stroke prevention in women with carotid stenosis were provided by a group of 9 international experts with consensus method. Results: Symptomatic women with severe carotid stenosis can be managed by CEA provided that the perioperative risk of the operators is low (<4%). Periprocedural stroke risks may be increased in symptomatic women if revascularization is performed by CAS; however, the choice of CAS vs CEA can be tailored in subgroups best fit for each procedure (e.g., women with restenosis or severe coronary disease, best suited for CAS; women with tortuous vessels or old age, best suited for CEA). There is currently limited evidence to consider medical therapy alone as the best choice for women with neurologically severe asymptomatic carotid stenosis, who should be best managed within randomized trials including a medical arm. Medical management and cardiovascular risk factor control must be implemented in all women with carotid stenosis in periprocedural period and lifelong regardless of whether or not intervention is planned. Conclusions: The suggestions provided in this article may constitute a decision-making basis for planning treatment of carotid stenosis in women. Most recommendations are of limited strength; however, it is unlikely that new robust data will emerge soon to induce relevant changes. PMID:23751919

Differential blood flow responses to CO2 in human internal and external carotid and vertebral arteries

PubMed Central

Sato, Kohei; Sadamoto, Tomoko; Hirasawa, Ai; Oue, Anna; Subudhi, Andrew W; Miyazawa, Taiki; Ogoh, Shigehiko

2012-01-01

Arterial CO2 serves as a mediator of cerebral blood flow (CBF), and its relative influence on the regulation of CBF is defined as cerebral CO2 reactivity. Our previous studies have demonstrated that there are differences in CBF responses to physiological stimuli (i.e. dynamic exercise and orthostatic stress) between arteries in humans. These findings suggest that dynamic CBF regulation and cerebral CO2 reactivity may be different in the anterior and posterior cerebral circulation. The aim of this study was to identify cerebral CO2 reactivity by measuring blood flow and examine potential differences in CO2 reactivity between the internal carotid artery (ICA), external carotid artery (ECA) and vertebral artery (VA). In 10 healthy young subjects, we evaluated the ICA, ECA, and VA blood flow responses by duplex ultrasonography (Vivid-e, GE Healthcare), and mean blood flow velocity in middle cerebral artery (MCA) and basilar artery (BA) by transcranial Doppler (Vivid-7, GE healthcare) during two levels of hypercapnia (3% and 6% CO2), normocapnia and hypocapnia to estimate CO2 reactivity. To characterize cerebrovascular reactivity to CO2, we used both exponential and linear regression analysis between CBF and estimated partial pressure of arterial CO2, calculated by end-tidal partial pressure of CO2. CO2 reactivity in VA was significantly lower than in ICA (coefficient of exponential regression 0.021 ± 0.008 vs. 0.030 ± 0.008; slope of linear regression 2.11 ± 0.84 vs. 3.18 ± 1.09% mmHg−1: VA vs. ICA, P < 0.01). Lower CO2 reactivity in the posterior cerebral circulation was persistent in distal intracranial arteries (exponent 0.023 ± 0.006 vs. 0.037 ± 0.009; linear 2.29 ± 0.56 vs. 3.31 ± 0.87% mmHg−1: BA vs. MCA). In contrast, CO2 reactivity in ECA was markedly lower than in the intra-cerebral circulation (exponent 0.006 ± 0.007; linear 0.63 ± 0.64% mmHg−1, P < 0.01). These findings indicate that vertebro-basilar circulation has lower CO2 reactivity than

Assessment of shear stress related parameters in the carotid bifurcation using mouse-specific FSI simulations.

PubMed

De Wilde, David; Trachet, Bram; Debusschere, Nic; Iannaccone, Francesco; Swillens, Abigail; Degroote, Joris; Vierendeels, Jan; De Meyer, Guido R Y; Segers, Patrick

2016-07-26

The ApoE(-)(/)(-) mouse is a common small animal model to study atherosclerosis, an inflammatory disease of the large and medium sized arteries such as the carotid artery. It is generally accepted that the wall shear stress, induced by the blood flow, plays a key role in the onset of this disease. Wall shear stress, however, is difficult to derive from direct in vivo measurements, particularly in mice. In this study, we integrated in vivo imaging (micro-Computed Tomography-µCT and ultrasound) and fluid-structure interaction (FSI) modeling for the mouse-specific assessment of carotid hemodynamics and wall shear stress. Results were provided for 8 carotid bifurcations of 4 ApoE(-)(/)(-) mice. We demonstrated that accounting for the carotid elasticity leads to more realistic flow waveforms over the complete domain of the model due to volume buffering capacity in systole. The 8 simulated cases showed fairly consistent spatial distribution maps of time-averaged wall shear stress (TAWSS) and relative residence time (RRT). Zones with reduced TAWSS and elevated RRT, potential indicators of atherosclerosis-prone regions, were located mainly at the outer sinus of the external carotid artery. In contrast to human carotid hemodynamics, no flow recirculation could be observed in the carotid bifurcation region. Copyright © 2015 Elsevier Ltd. All rights reserved.

Carotid plaque characterization using CT and MRI scans for synergistic image analysis

NASA Astrophysics Data System (ADS)

Getzin, Matthew; Xu, Yiqin; Rao, Arhant; Madi, Saaussan; Bahadur, Ali; Lennartz, Michelle R.; Wang, Ge

2014-09-01

Noninvasive determination of plaque vulnerability has been a holy grail of medical imaging. Despite advances in tomographic technologies , there is currently no effective way to identify vulnerable atherosclerotic plaques with high sensitivity and specificity. Computed tomography (CT) and magnetic resonance imaging (MRI) are widely used, but neither provides sufficient information of plaque properties. Thus, we are motivated to combine CT and MRI imaging to determine if the composite information can better reflect the histological determination of plaque vulnerability. Two human endarterectomy specimens (1 symptomatic carotid and 1 stable femoral) were imaged using Scanco Medical Viva CT40 and Bruker Pharmascan 16cm 7T Horizontal MRI / MRS systems. μCT scans were done at 55 kVp and tube current of 70 mA. Samples underwent RARE-VTR and MSME pulse sequences to measure T1, T2 values, and proton density. The specimens were processed for histology and scored for vulnerability using the American Heart Association criteria. Single modality-based analyses were performed through segmentation of key imaging biomarkers (i.e. calcification and lumen), image registration, measurement of fibrous capsule, and multi-component T1 and T2 decay modeling. Feature differences were analyzed between the unstable and stable controls, symptomatic carotid and femoral plaque, respectively. By building on the techniques used in this study, synergistic CT+MRI analysis may provide a promising solution for plaque characterization in vivo.

Carotid bypass: a safe and durable solution for recurrent carotid stenosis.

PubMed

Spinelli, Francesco; Martelli, Eugenio; Stilo, Francesco; Pipitò, Narayana; Benedetto, Filippo; Spinelli, Domenico; Squillaci, Domenico; De Caridi, Giovanni; Barillà, David

2014-07-01

The long-term results of carotid artery stenting (CAS) for post-carotid endarterectomy (CEA) restenosis are disappointing (4-year patency rates: ∼75%). Since 1988, our group has offered carotid bypass (CB) as an alternative to redo CEA and later also to CAS in this setting. The aim of this retrospective study was to investigate early and late outcomes associated with CB in this population. Data were collected from patients treated with CB in the year 2000-2012 for significant/symptomatic post-CEA restenosis (or intra-stent restenosis [ISR] after CAS for post-CEA restenosis). All patients had good life expectancy. CB was performed under loco-regional anesthesia. With the aid of sequential vessel clamping, the graft (great saphenous vein [GSV] or polytetrafluoroethylene) was anastomosed with the common carotid artery (side-to-end) and the distal internal carotid artery (end-to-side). Patients were followed with clinical and duplex scan assessments at 1, 3, and 6 months and yearly thereafter. The study population comprised 21 patients (mean age 67.3 years; 17 men). CB was performed for post-CEA restenosis (or ISR after CAS for post-CEA restenosis, n=3) 51.2 months (mean) after the previous operation. GSV grafts were used in half of the cases (n=11; 52.4%); temporary shunting was used in 4 (19%) patients. Intraoperative complications (none fatal) occurred in 4 (19%) patients (3 transient peripheral nerve injuries, 1 cervical hematoma). During follow-up (mean 64.8 months), there were no neurologic complications or restenoses. Overall mortality was 33.3% (6 deaths from acute myocardial infarctions, 1 from a ruptured abdominal aortic aneurysm). For post-CEA restenosis (or ISR after CAS for post-CEA restenosis), CB offers superior long-term patency rates than CAS (or redo angioplasty) and an acceptable risk of cranial nerve damage. Copyright © 2014 Elsevier Inc. All rights reserved.

Fatal carotid dissection after blunt head trauma.

PubMed

Tartara, F; Regolo, P; Servadei, F; Versari, P P; Giovanelli, M

2000-06-01

Occurrence of internal carotid artery injuries associated with skull base fracture has been reported. A. report a case of fatal intracranial carotid dissection related to petrous fracture involving the carotid canal. Identification of carotid lesions may be difficult and generally related to appearance of unexpected neurological deficit. Skull base fractures may be considered an indirect sign for detection of vascular injury. Patterns of the fracture are of paramount importance; routine CT scan may fail to detect basilar fractures and high definition fine-cut CT scan should be executed to carefully identify and evaluate fractures. Temporal and sphenoid bone fractures are common in head trauma and involvement of the course of the carotid artery is frequent. The involvement of the intracranial carotid artery course represents a direct risk factor for lesions of the petrous, lacerum and cavernous segments of the carotid artery. Early diagnosis of post-traumatic vascular injury may lead to prognosis improvement because of effectiveness of heparin anticoagulant therapy. Then vascular screening is recommendable in cases with complex fractures of the skull base and particularly fracturing along the course of the carotid artery. Magnetic resonance angiography may be considered the first line diagnostic tools for vascular screening. Angiography may be reserved for patients with a proven lesion or rapid neurological deterioration taking into account the possibility of interventional treatment.

Percutaneous Injection of Lidocaine Within the Carotid Body Area in Carotid Artery Stenting: An 'Old-New' Technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mourikis, Dimitrios; Chatoupis, Konstantinos, E-mail: kchatoupis@yahoo.g; Katsenis, Konstantinos

2008-07-15

Severe bradycardia is a common untoward effect during balloon angioplasty when performing carotid artery stenting. Therefore atropine injection even before dilatation and the presence of an anesthesiologist are advocated in all patients. In the surgical literature, injection of a local anesthetic agent into the carotid sinus before carotid endarterectomy was performed in an attempt to ameliorate perioperative hemodynamic instability. This study was undertaken to test the hypothesis that percutaneous infiltration of the carotid sinus with local anesthetic immediately before balloon dilatation reduces bradycardia and ameliorates the need for atropine injection or the presence of an anesthesiologist. Infiltration of the carotidmore » sinus with 5 ml of 1% lidocaine, 3 min before dilatation, was performed in 30 consecutive patients. No one exhibited any significant rhythm change that required atropine injection. The anesthesiologist did not face any hemodynamic instability during the carotid artery stenting procedure.« less

Three-dimensional color Doppler imaging of the carotid artery

NASA Astrophysics Data System (ADS)

Picot, Paul A.; Rickey, Daniel W.; Mitchell, Ross; Rankin, Richard N.; Fenster, Aaron

1991-05-01

Stroke is the third leading cause of death in the United States. It is caused by ischemic injury to the brain, usually resulting from emboli from atherosclerotic plaques. The carotid bifurcation in humans is prone to atherosclerotic disease and is a site where emboli may originate. Currently, carotid stenoses are evaluated by non-invasive duplex Doppler ultrasound, with preoperative verification by intra-arterial angiography. We have developed a system that uses a color Doppler ultrasound imaging system to acquire in-vivo 3-D color Doppler images of the human carotid artery, with the aim of increasing the diagnostic accuracy of ultrasound and decreasing the use of angiography for verification. A clinical TL Ultramark 9 color Doppler ultrasound system was modified by mounting the hand-held ultrasound scan head on a motor-driven translation stage. The stage allows planar ultrasound images to be acquired over 45 mm along the neck between the clavicle and the mandible. A 3- D image is acquired by digitizing, in synchrony with the cardiac cycle, successive color ultrasound video images as the scan head is stepped along the neck. A complete volume set of 64 frames, comprising some 15 megabytes of data, requires approximately 2 minutes to acquire. The volume image is reformatted and displayed on a Sun 4/360 workstation equipped with a TAAC-1 graphics accelerator. The 3-D image may be manipulated in real time to yield the best view of blood flow in the bifurcation.

Numerical study of oxygen transport in a carotid bifurcation

NASA Astrophysics Data System (ADS)

Tada, Shigeru

2010-07-01

This study investigates the oxygen mass transport in the region around the human carotid bifurcation, particularly addressing the effects of bifurcation geometry and pulsatile blood flow on the oxygen transport between the blood flow and artery wall tissue, coupled with the metabolic oxygen consumption and oxygen diffusion in the artery wall tissue. The temporal variations and spatial distributions of the oxygen tension are predicted quantitatively using a geometric model of the human carotid bifurcation and realistic blood flow waveforms. Results reveal that the flow separation at the outside wall of the sinus of the internal carotid artery (ICA) can markedly alter the flow pattern, oxygen tension and the oxygen wall flux. Results also clarify that the flow unsteadiness has a secondary effect on the oxygen tension inside the wall. The non-dimensional oxygen flux, the Sherwood number Sh, at the outside wall of the ICA sinus, takes markedly lower values of about 45 than at other sites because the rates of oxygen transport by the convective flow are reduced at the outside wall of the ICA sinus. The transverse distributions of the oxygen tension inside the artery wall show parabolic profiles having minima in the middle of the wall thickness, with the lowest value of 35 mmHg. These predicted distributions of the oxygen tension inside the wall closely resemble those obtained from experiments. The results demonstrate that hypoxic zones appear inside the artery walls at locations where atherosclerotic lesions are prone to develop.

A manual carotid compression technique to overcome difficult filter protection device retrieval during carotid artery stenting.

PubMed

Nii, Kouhei; Nakai, Kanji; Tsutsumi, Masanori; Aikawa, Hiroshi; Iko, Minoru; Sakamoto, Kimiya; Mitsutake, Takafumi; Eto, Ayumu; Hanada, Hayatsura; Kazekawa, Kiyoshi

2015-01-01

We investigated the incidence of embolic protection device retrieval difficulties at carotid artery stenting (CAS) with a closed-cell stent and demonstrated the usefulness of a manual carotid compression assist technique. Between July 2010 and October 2013, we performed 156 CAS procedures using self-expandable closed-cell stents. All procedures were performed with the aid of a filter design embolic protection device. We used FilterWire EZ in 118 procedures and SpiderFX in 38 procedures. The embolic protection device was usually retrieved by the accessory retrieval sheath after CAS. We applied a manual carotid compression technique when it was difficult to navigate the retrieval sheath through the deployed stent. We compared clinical outcomes in patients where simple retrieval was possible with patients where the manual carotid compression assisted technique was used for retrieval. Among the 156 CAS procedures, we encountered 12 (7.7%) where embolic protection device retrieval was hampered at the proximal stent terminus. Our manual carotid compression technique overcame this difficulty without eliciting neurologic events, artery dissection, or stent deformity. In patients undergoing closed-cell stent placement, embolic protection device retrieval difficulties may be encountered at the proximal stent terminus. Manual carotid compression assisted retrieval is an easy, readily available solution to overcome these difficulties. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Comparative Analysis of the Biaxial Mechanical Behavior of Carotid Wall Tissue and Biological and Synthetic Materials Used for Carotid Patch Angioplasty

PubMed Central

Kamenskiy, Alexey V.; Pipinos, Iraklis I.; MacTaggart, Jason N.; Jaffar Kazmi, Syed A.; Dzenis, Yuris A.

2011-01-01

Patch angioplasty is the most common technique used for the performance of carotid endarterectomy. A large number of patching materials are available for use while new materials are being continuously developed. Surprisingly little is known about the mechanical properties of these materials and how these properties compare with those of the carotid artery wall. Mismatch of the mechanical properties can produce mechanical and hemodynamic effects that may compromise the long-term patency of the endarterectomized arterial segment. The aim of this paper was to systematically evaluate and compare the biaxial mechanical behavior of the most commonly used patching materials. We compared PTFE (n = 1), Dacron (n = 2), bovine pericardium (n = 10), autogenous greater saphenous vein (n = 10), and autogenous external jugular vein (n = 9) with the wall of the common carotid artery (n = 18). All patching materials were found to be significantly stiffer than the carotid wall in both the longitudinal and circumferential directions. Synthetic patches demonstrated the most mismatch in stiffness values and vein patches the least mismatch in stiffness values compared to those of the native carotid artery. All biological materials, including the carotid artery, demonstrated substantial nonlinearity, anisotropy, and variability; however, the behavior of biological and biologically-derived patches was both qualitatively and quantitatively different from the behavior of the carotid wall. The majority of carotid arteries tested were stiffer in the circumferential direction, while the opposite anisotropy was observed for all types of vein patches and bovine pericardium. The rates of increase in the nonlinear stiffness over the physiological stress range were also different for the carotid and patching materials. Several carotid wall samples exhibited reverse anisotropy compared to the average behavior of the carotid tissue. A similar characteristic was observed for

Carotid Endarterectomy and Carotid Artery Stenting in the US Medicare Population, 1999-2014

PubMed Central

Jones, Michael R.; Leifheit, Erica C.; Sheffet, Alice J.; Howard, George; Lal, Brajesh K.; Howard, Virginia J.; Wang, Yun; Curtis, Jeptha; Brott, Thomas G.

2017-01-01

Importance Carotid endarterectomy and carotid artery stenting are the leading approaches to revascularization for carotid stenosis, yet contemporary data on trends in rates and outcomes are limited. Objective To describe US national trends in performance and outcomes of carotid endarterectomy and stenting among Medicare beneficiaries from 1999 to 2014. Design, Setting, and Participants Serial cross-sectional analysis of Medicare fee-for-service beneficiaries aged 65 years or older from 1999 to 2014 using the Medicare Inpatient and Denominator files. Spatial mixed models adjusted for age, sex, and race were fit to calculate county-specific risk-standardized revascularization rates. Mixed models were fit to assess trends in outcomes after adjustment for demographics, comorbidities, and symptomatic status. Exposures Carotid endarterectomy and carotid artery stenting. Main Outcomes and Measures Revascularization rates per 100 000 beneficiary-years of fee-for-service enrollment, in-hospital mortality, 30-day stroke or death, 30-day stroke, myocardial infarction, or death, 30-day all-cause mortality, and 1-year stroke. Results During the study, 937 111 unique patients underwent carotid endarterectomy (mean age, 75.8 years; 43% women) and 231 077 underwent carotid artery stenting (mean age, 75.4 years; 49% women). There were 81 306 patients who underwent endarterectomy in 1999 and 36 325 in 2014; national rates per 100 000 beneficiary-years decreased from 298 in 1999-2000 to 128 in 2013-2014 (P < .001). The number of patients who underwent stenting ranged from 10 416 in 1999 to 22 865 in 2006 (an increase per 100 000 beneficiary-years from 40 in 1999-2000 to 75 in 2005-2006; P < .001); by 2014, there were 10 208 patients who underwent stenting and the rate decreased to 38 per 100 000 beneficiary-years (P < .001). Outcomes improved over time despite increases in vascular risk factors (eg, hypertension prevalence increased from 67% to 81

Artificial Intelligence Estimation of Carotid-Femoral Pulse Wave Velocity using Carotid Waveform.

PubMed

Tavallali, Peyman; Razavi, Marianne; Pahlevan, Niema M

2018-01-17

In this article, we offer an artificial intelligence method to estimate the carotid-femoral Pulse Wave Velocity (PWV) non-invasively from one uncalibrated carotid waveform measured by tonometry and few routine clinical variables. Since the signal processing inputs to this machine learning algorithm are sensor agnostic, the presented method can accompany any medical instrument that provides a calibrated or uncalibrated carotid pressure waveform. Our results show that, for an unseen hold back test set population in the age range of 20 to 69, our model can estimate PWV with a Root-Mean-Square Error (RMSE) of 1.12 m/sec compared to the reference method. The results convey the fact that this model is a reliable surrogate of PWV. Our study also showed that estimated PWV was significantly associated with an increased risk of CVDs.

Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial

PubMed Central

2010-01-01

Summary Background Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. Methods The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. Findings The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4·0%) events of disabling stroke or death in the stenting group compared with 27 (3·2%) events in the endarterectomy group (hazard ratio [HR] 1·28, 95% CI 0·77–2·11). The incidence of stroke, death, or procedural myocardial infarction was 8·5% in the stenting group compared with 5·2% in the endarterectomy group (72 vs 44 events

Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial.

PubMed

Ederle, Jörg; Dobson, Joanna; Featherstone, Roland L; Bonati, Leo H; van der Worp, H Bart; de Borst, Gert J; Lo, T Hauw; Gaines, Peter; Dorman, Paul J; Macdonald, Sumaira; Lyrer, Philippe A; Hendriks, Johanna M; McCollum, Charles; Nederkoorn, Paul J; Brown, Martin M

2010-03-20

Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4.0%) events of disabling stroke or death in the stenting group compared with 27 (3.2%) events in the endarterectomy group (hazard ratio [HR] 1.28, 95% CI 0.77-2.11). The incidence of stroke, death, or procedural myocardial infarction was 8.5% in the stenting group compared with 5.2% in the endarterectomy group (72 vs 44 events; HR 1.69, 1.16-2.45, p=0.006). Risks of any

National trends in carotid artery revascularization surgery.

PubMed

Dumont, Travis M; Rughani, Anand I

2012-06-01

Several randomized trials have emerged with conflicting data on the overall safety of carotid artery stenting (CAS) in comparison with carotid endarterectomy (CEA). The authors hypothesize that changes in national trends correspond to publication of randomized trials, including an increase in utilization of CAS after publication of trials favorable to CAS (for example, Carotid and Vertebral Artery Transluminal Angioplasty Study [CAVATAS] and Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy [SAPPHIRE]) and decrease in utilization of CAS after publication of trials favorable to CEA (for example, Endarterectomy versus Stenting in Patients with Symptomatic Severe Carotid Stenosis [EVA3-S] and Stent-Supported Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy [SPACE]). The Nationwide Inpatient Sample was obtained for the years 1998-2008. Individual cases were isolated for principal diagnosis of unilateral or bilateral carotid artery stenosis or occlusion undergoing CEA or CAS. The percentage of CAS for all carotid revascularization procedures was calculated for each year. Perioperative inpatient morbidity, including stroke or death, were calculated and compared. The percentage of patients undergoing CAS increased yearly from the start of the observed period to the end, with the exception of a decrease in 2007. The peak utilization of CAS for carotid artery revascularization procedures was 15% of all cases in 2006. The stroke or death rate was consistent at 5% among all patients undergoing CEA for all years, while the incidence of stroke or death decreased among patients undergoing CAS from 9% in 1998 to 5% in 2008. The practice of CAS in the US is expanding, from less than 3% of all carotid artery revascularization procedures to 13% in 2008. The utilization of CAS was seen to correlate with publication of randomized trials. Utilization nearly doubled in 2005 after publication of the CAS-favorable SAPPHIRE in 2004

Cerebral intolerance during flow arrested carotid angioplasty.

PubMed

St Louis, Myron; Park, Brian D; Dahn, Michael; Bozeman, Patricia

2012-01-01

The use of flow arrest as a means of providing cerebral protection during carotid angioplasty offers the advantages of improved efficiency of debris removal and the ability to provide protection under unfavorable (tortuous) anatomic circumstances. However, in contrast to the filtration methods of cerebral protection, this modality requires complete interruption of antegrade carotid artery flow during balloon angioplasty and stent deployment. We report our experience with 9 patients undergoing carotid angioplasty with the Mo.Ma device, which utilizes common and external carotid artery balloon occlusion during the angioplasty procedure. We assessed the clinical outcomes and intraprocedural hemodynamic data. The average duration of carotid occlusion was 8.3 minutes. Of the 9 patients, 2 patients (22%) experienced cerebral intolerance. No stroke occurred in this patient cohort. There appeared to be a poor relationship between procedure intolerance and the presence of significant contralateral stenosis or low carotid back pressure. Furthermore, the incidence of postangioplasty hypotension was not clearly related to cerebral intolerance. Carotid angioplasty with stenting can be safely conducted with flow arrest as an alternative to filter-type cerebral protection devices. However, because cerebral intolerance is not an infrequent occurrence with this approach, clinicians must be cognizant of management strategies for transient cerebral intolerance.

Reliability of panoramic radiograph for carotid atheroma detection: a study in patients who fulfill the criteria for carotid endarterectomy.

PubMed

Damaskos, Spyros; Griniatsos, John; Tsekouras, Nikolaos; Georgopoulos, Sotirios; Klonaris, Chris; Bastounis, Elias; Tsiklakis, Kostas

2008-11-01

To evaluate the reliability of panoramic radiograph (PR) for carotid artery atheroma detection, by comparing its results with the carotid-vertebral digital subtraction angiography (DSA) findings, as well as with the detected calcium deposition in the carotid plaques, which were surgically resected, using direct radiographs. Forty consecutive patients suffering from carotid artery atherosclerotic occlusive disease confirmed by preoperative DSA, fulfilling the criteria for carotid endarterectomy, were operated on. Preoperatively, all of the patients had undergone PR, while postoperatively all of the surgically resected carotid plaques were radiographed using radiographic films and submitted to histologic examination. Compared with the DSA and the radiographic film findings, the PR results were classified as: 1) true-positive; 2) true-negative; 3) false-positive; or 4) false-negative. Panoramic radiograph has low sensitivity and specificity compared with the DSA findings and the direct radiographs results. However, a positive predictive value (PPV) of 100% per patient as well as for luminal stenosis >80% was documented. Even in the subgroup of patients who fulfill the criteria for carotid endarterectomy, PR has a low sensitivity and specificity; therefore, it cannot be considered to be a useful screening tool for atheroma detection in the general dental population. However, the 100% PPV per patient and for luminal stenosis >80%, indicates that positive calcification PR findings at the C(3)-C(4) region are highly suggestive for carotid artery atherosclerotic occlusive disease. Therefore, especially asymptomatic patients should be referred for further examination.

Prevalence by sex of preclinical carotid atherosclerosis in newly diagnosed type 2 diabetes.

PubMed

Catalan, M; Herreras, Z; Pinyol, M; Sala-Vila, A; Amor, A J; de Groot, E; Gilabert, R; Ros, E; Ortega, E

2015-08-01

There is clinical trial evidence that only early, intensive risk factor control can reduce cardiovascular disease (CVD) morbidity and mortality in type 2 diabetes (T2DM). However, there is little information regarding preclinical atherosclerosis at diabetes diagnosis. We assessed carotid atherosclerosis in new-onset T2DM and control individuals without prior CVD. In a cross-sectional case-control study, we determined intima-media thickness (IMT) and plaque (IMT ≥1.5 mm) by ultrasound at all carotid sites in new-onset T2DM patients and controls. We assessed 106 T2DM patients, median age 62 years, 46% women, 19% smokers, 54% with hypertension, and 41% with dyslipidemia and 99 non-diabetic subjects matched by age, sex, and cardiovascular risk factors. Compared to controls, T2DM patients had higher common carotid artery (CCA)-IMT (median 0.725 vs. 0.801 mm, p = 0.01), bulb-IMT (0.976 vs. 1.028 mm, p = 0.12), and internal carotid artery (ICA)-IMT (0.727 vs. 0.802 mm, p = 0.04). The prevalence of total plaque (60% vs. 72%, p = 0.06), ICA plaque (20% vs. 42%, p < 0.01), and harboring ≥3 plaques (16% vs. 35% p < 0.01) was also higher in T2DM. Plaque score (sum of maximum plaque heights) was also higher (p < 0.01) in T2DM. Diabetic women showed more advanced carotid atherosclerosis than diabetic men when they were compared with their respective non-diabetic counterparts. There is a high prevalence of preclinical atherosclerosis (carotid plaque presence and burden) in new-onset T2DM subjects, especially in women. Early, still reversible, preclinical atherosclerosis may explain in part why early intervention is effective to prevent CVD in this patient population. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparative Review of the Treatment Methodologies of Carotid Stenosis

PubMed Central

Bae, Coney; Szuchmacher, Mauricio; Chang, John B.

2015-01-01

The treatment of carotid stenosis entails three methodologies, namely, medical management, carotid angioplasty and stenting (CAS), as well as carotid endarterectomy (CEA). The North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST) have shown that symptomatic carotid stenosis greater than 70% is best treated with CEA. In asymptomatic patients with carotid stenosis greater than 60%, CEA was more beneficial than treatment with aspirin alone according to the Asymptomatic Carotid Atherosclerosis (ACAS) and Asymptomatic Carotid Stenosis Trial (ACST) trials. When CAS is compared with CEA, the CREST resulted in similar rates of ipsilateral stroke and death rates regardless of symptoms. However, CAS not only increased adverse effects in women, it also amplified stroke rates and death in elderly patients compared with CEA. CAS can maximize its utility in treating focal restenosis after CEA and patients with overwhelming cardiac risk or prior neck irradiation. When performing CEA, using a patch was equated to a more durable result than primary closure, whereas eversion technique is a new methodology deserving a spotlight. Comparing the three major treatment strategies of carotid stenosis has intrinsic drawbacks, as most trials are outdated and they vary in their premises, definitions, and study designs. With the newly codified best medical management including antiplatelet therapies with aspirin and clopidogrel, statin, antihypertensive agents, strict diabetes control, smoking cessation, and life style change, the current trials may demonstrate that asymptomatic carotid stenosis is best treated with best medical therapy. The ongoing trials will illuminate and reshape the treatment paradigm for symptomatic and asymptomatic carotid stenosis. PMID:26417191

Diagnosis and management of carotid stenosis: a review.

PubMed

Nussbaum, E S

2000-01-01

Since its introduction in the 1950s, carotid endarterectomy has become one of the most frequently performed operations in the United States. The tremendous appeal of a procedure that decreases the risk of stroke, coupled with the large number of individuals in the general population with carotid stenosis, has contributed to its popularity. To provide optimal patient care, the practicing physician must have a firm understanding of the proper evaluation and management of carotid stenosis. Nevertheless, because of the large number of clinical trials performed over the last decade addressing the treatment of stroke and carotid endarterectomy, the care of patients with carotid stenosis remains a frequently misunderstood topic. This review summarizes the current evaluation and treatment options for carotid stenosis and provides a rational management algorithm for this prevalent disease process.

Postoperative Dysphagia in Debranching Thoracic Endovascular Aortic Repair with Retroesophageal Carotid-Carotid Bypass.

PubMed

Yoneyama, Fumiya; Sato, Fujio; Tokunaga, Chiho; Sakamoto, Hiroaki; Enomoto, Yoshiharu; Watanabe, Yutaka; Hiramatsu, Yuji

2017-08-01

A carotid-carotid bypass is commonly used in debranching thoracic endovascular aortic repair. When the bypass graft is placed in the retroesophageal position, the esophagus may be compressed by the graft from behind. Therefore, dysphagia may occur postoperatively as a serious complication. To avoid this issue, we recommend placing the bypass graft below the cricoid cartilage. Copyright © 2017 Elsevier Inc. All rights reserved.

Carotid stenosis - basing treatment on individual patients' needs. Optimal medical therapy alone or accompanied by stenting or endarterectomy.

PubMed

Langhoff, Ralf

2018-01-01

Though carotid artery stenosis is a known origin of stroke, risk assessment and treatment modality are not yet satisfactorily established. Guideline updates according to latest evidence are expected shortly. Current clinical weakness concerns in particular the identification of "at-risk" patients. Beside the symptomatic status and the degree of stenosis, further signs of unstable plaque on carotid and cerebral imaging should be considered. Moreover, medical and endovascular therapy are continuously improving. Randomized trials and meta-analyses have shown similar long-term results for protected carotid artery stenting and endarterectomy. However, endovascular revascularization was associated with an increased 30-day rate of minor strokes. Newly developed embolic protection devices could possibly compensate for this disadvantage. Furthermore, high-level optimal medical therapy alone is currently being evaluated comparatively. We assume that a comprehensive evaluation of plaque vulnerability, serious consideration of advanced embolic protection, and more space for optimal medical therapy alone according to latest evidence, will benefit patients with carotid stenosis.

Increased Vessel Depiction of the Carotid Bifurcation with a Specialized 16-Channel Phased Array Coil at 3T

PubMed Central

Tate, Quinn; Kim, Seong-Eun; Treiman, Gerald; Parker, Dennis L.; Hadley, J. Rock

2012-01-01

The purpose of this work was to design and construct a multi-channel receive-only RF coil for 3 Tesla magnetic resonance imaging of the human carotid artery and bifurcation with optimized signal to noise ratio in the carotid vessels along the full extent of the neck. A neck phantom designed to match the anatomy of a subject with a neck representing the body habitus often seen in subjects with carotid arterial disease, was constructed. Sixteen circular coil elements were arranged on a semi-rigid fiberglass former that closely fit the shape of the phantom, resulting in a 16-channel bilateral phased array coil. Comparisons were made between this coil and a typical 4-channel carotid coil in a study of 10 carotid vessels in 5 healthy volunteers. The 16-channel carotid coil showed a 73% average improvement in signal to noise ratio (SNR) at the carotid bifurcation. This coil also maintained an SNR greater than the peak SNR of the 4-channel coil over a vessel length of 10 cm. The resulting increase in SNR improved vessel depiction of the carotid arteries over an extended field of view, and demonstrated better image quality for higher parallel imaging reduction factors compared to the 4-channel coil. PMID:22777692

Sacrifice and extracranial reconstruction of the common or internal carotid artery in advanced head and neck carcinoma: Review and meta-analysis.

PubMed

Bäck, Leif J J; Aro, Katri; Tapiovaara, Laura; Vikatmaa, Pirkka; de Bree, Remco; Fernández-Álvarez, Verónica; Kowalski, Luiz P; Nixon, Iain J; Rinaldo, Alessandra; Rodrigo, Juan P; Robbins, K Thomas; Silver, Carl E; Snyderman, Carl H; Suárez, Carlos; Takes, Robert P; Ferlito, Alfio

2018-06-01

Sacrifice and reconstruction of the carotid artery in cases of head and neck carcinoma with invasion of the common or internal carotid artery is debated. We conducted a systematic search of electronic databases and provide a review and meta-analysis. Of the 72 articles identified, 24 met the inclusion criteria resulting in the inclusion of 357 patients. The overall perioperative 30-day mortality was 3.6% (13/357). Permanent cerebrovascular complications occurred in 3.6% (13/357). Carotid blowout episodes were encountered in 1.4% (5/357). The meta-regression analysis showed a significant difference in 1-year overall survival between reports published from 1981-1999 (37.0%) and 2001-2016 (65.4%; P = .02). This review provides evidence that sacrifice with extracranial reconstruction of common or internal carotid artery in selected patients with head and neck carcinoma may improve survival with acceptable complication rates. However, all of the published literature is retrospective involving selected series and, therefore, precludes determining the absolute effectiveness of the surgery. © 2018 Wiley Periodicals, Inc.

Application of a time-resolved optical brain imager for monitoring cerebral oxygenation during carotid surgery.

PubMed

Kacprzak, Michal; Liebert, Adam; Staszkiewicz, Walerian; Gabrusiewicz, Andrzej; Sawosz, Piotr; Madycki, Grzegorz; Maniewski, Roman

2012-01-01

Recent studies have shown that time-resolved optical measurements of the head can estimate changes in the absorption coefficient with depth discrimination. Thus, changes in tissue oxygenation, which are specific to intracranial tissues, can be assessed using this advanced technique, and this method allows us to avoid the influence of changes to extracerebral tissue oxygenation on the measured signals. We report the results of time-resolved optical imaging that was carried out during carotid endarterectomy. This surgery remains the "gold standard" treatment for carotid stenosis, and intraoperative brain oxygenation monitoring may improve the safety of this procedure. A time-resolved optical imager was utilized within the operating theater. This instrument allows for the simultaneous acquisition of 32 distributions of the time-of-flight of photons at two wavelengths on both hemispheres. Analysis of the statistical moments of the measured distributions of the time-of-flight of photons was applied for estimating changes in the absorption coefficient as a function of depth. Time courses of changes in oxy- and deoxyhemoglobin of the extra- and intracerebral compartments during cross-clamping of the carotid arteries were obtained. A decrease in the oxyhemoglobin concentration and an increase in the deoxyhemoglobin concentrations were observed in a large area of the head. Large changes were observed in the hemisphere ipsilateral to the site of clamped carotid arteries. Smaller amplitude changes were noted at the contralateral site. We also found that changes in the hemoglobin signals, as estimated from intracerebral tissue, are very sensitive to clamping of the internal carotid artery, whereas its sensitivity to clamping of the external carotid artery is limited. We concluded that intraoperative multichannel measurements allow for imaging of brain tissue hemodynamics. However, when monitoring the brain during carotid surgery, a single-channel measurement may be sufficient.

Comparison of grey scale median (GSM) measurement in ultrasound images of human carotid plaques using two different softwares.

PubMed

Östling, Gerd; Persson, Margaretha; Hedblad, Bo; Gonçalves, Isabel

2013-11-01

Grey scale median (GSM) measured on ultrasound images of carotid plaques has been used for several years now in research to find the vulnerable plaque. Centres have used different software and also different methods for GSM measurement. This has resulted in a wide range of GSM values and cut-off values for the detection of the vulnerable plaque. The aim of this study was to compare the values obtained with two different softwares, using different standardization methods, for the measurement of GSM on ultrasound images of carotid human plaques. GSM was measured with Adobe Photoshop(®) and with Artery Measurement System (AMS) on duplex ultrasound images of 100 consecutive medium- to large-sized carotid plaques of the Beta-blocker Cholesterol-lowering Asymptomatic Plaque Study (BCAPS). The mean values of GSM were 35·2 ± 19·3 and 55·8 ± 22·5 for Adobe Photoshop(®) and AMS, respectively. Mean difference was 20·45 (95% CI: 19·17-21·73). Although the absolute values of GSM differed, the agreement between the two measurements was good, correlation coefficient 0·95. A chi-square test revealed a kappa value of 0·68 when studying quartiles of GSM. The intra-observer variability was 1·9% for AMS and 2·5% for Adobe Photoshop. The difference between softwares and standardization methods must be taken into consideration when comparing studies. To avoid these problems, researcher should come to a consensus regarding software and standardization method for GSM measurement on ultrasound images of plaque in the arteries. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Clinical and electroencephalographic features of carotid sinus syncope induced by internal carotid artery angioplasty.

PubMed

Martinez-Fernandez, E; García, F Boza; Gonzalez-Marcos, J R; Peralta, A Gil; Garcia, A Gonzalez; Deya, A Mayol

2008-02-01

Carotid sinus syncope may occur acutely during internal carotid artery angioplasty (CA). We performed this study to investigate the clinical, electroencephalographic (EEG), and hemodynamic features of carotid sinus syncope induced by CA. Between 1992 and 2003, clinical, EEG, and cardiovascular monitoring was performed in 359 consecutive patients undergoing CA. Carotid sinus reaction (CSR) and syncope occurred in 62.7% and 18.6% of the procedures, respectively. CSR and syncopal spells were classified into cardioinhibitory, vasodepressor, and mixed type. Syncope occurred more frequently in patients with cardioinhibitory CSR (P < .001). The odds ratios for the risk of syncope in patients with cardioinhibitory CSR and vasodepressor/mixed CSR were 6.9 and 1.4, respectively. Sixty-one patients had cardioinhibitory syncope; 7 had the vasodepressor/mixed type. Thirteen spells were not related to cardiovascular disturbances. This last syncope subtype was significantly associated with brain hemodynamic disturbances, including a decrease in cerebral vasoreactivity (P = .04) and the absence of function of both communicating arteries (P = .03). Convulsive movements resembling supplementary sensorimotor seizures occurred in 79% of patients who experienced syncopal spells. EEG changes were more prominent in patients with cardioinhibitory syncope. Syncope occurs frequently in patients undergoing CA and can be misdiagnosed as seizures. The most frequent mechanism was a cardioinhibitory response. Cerebral hemodynamic disturbances may play a crucial role in the pathophysiology of syncope with normal sinus rhythm and normotension. Moreover, direct depression of the CNS following carotid sinus distension is likely to be involved.

Cardiac Iodine-123-Meta-Iodo-Benzylguanidine Uptake in Carotid Sinus Hypersensitivity

PubMed Central

Tan, Maw Pin; Murray, Alan; Hawkins, Terry; Chadwick, Thomas J.; Kerr, Simon R. J.; Parry, Steve W.

2015-01-01

Background Carotid sinus syndrome is the association of carotid sinus hypersensitivity with syncope, unexplained falls and drop attacks in generally older people. We evaluated cardiac sympathetic innervation in this disorder in individuals with carotid sinus syndrome, asymptomatic carotid sinus hypersensitivity and controls without carotid sinus hypersensitivity. Methods Consecutive patients diagnosed with carotid sinus syndrome at a specialist falls and syncope unit were recruited. Asymptomatic carotid sinus hypersensitivity and non-carotid sinus hypersensitivity control participants recruited from a community-dwelling cohort. Cardiac sympathetic innervation was determined using Iodine-123-metaiodobenzylguanidine (123-I-MIBG) scanning. Heart to mediastinal uptake ratio (H:M) were determined for early and late uptake on planar scintigraphy at 20 minutes and 3 hours following intravenous injection of 123-I-MIBG. Results Forty-two subjects: carotid sinus syndrome (n = 21), asymptomatic carotid sinus hypersensitivity (n = 12) and no carotid sinus hypersensitivity (n = 9) were included. Compared to the non- carotid sinus hypersensitivity control group, the carotid sinus syndrome group had significantly higher early H:M (estimated mean difference, B = 0.40; 95% confidence interval, CI = 0.13 to 0.67, p = 0.005) and late H:M (B = 0.32; 95%CI = 0.03 to 0.62, p = 0.032). There was, however, no significant difference in early H:M (p = 0.326) or late H:M (p = 0.351) between the asymptomatic carotid sinus hypersensitivity group and non- carotid sinus hypersensitivity controls. Conclusions Cardiac sympathetic neuronal activity is increased relative to age-matched controls in individuals with carotid sinus syndrome but not those with asymptomatic carotid sinus hypersensitivity. Blood pressure and heart rate measurements alone may therefore represent an over simplification in the assessment for carotid sinus syndrome and the relative increase in cardiac sympathetic innervation

Cardiac Iodine-123-Meta-Iodo-Benzylguanidine Uptake in Carotid Sinus Hypersensitivity.

PubMed

Tan, Maw Pin; Murray, Alan; Hawkins, Terry; Chadwick, Thomas J; Kerr, Simon R J; Parry, Steve W

2015-01-01

Carotid sinus syndrome is the association of carotid sinus hypersensitivity with syncope, unexplained falls and drop attacks in generally older people. We evaluated cardiac sympathetic innervation in this disorder in individuals with carotid sinus syndrome, asymptomatic carotid sinus hypersensitivity and controls without carotid sinus hypersensitivity. Consecutive patients diagnosed with carotid sinus syndrome at a specialist falls and syncope unit were recruited. Asymptomatic carotid sinus hypersensitivity and non-carotid sinus hypersensitivity control participants recruited from a community-dwelling cohort. Cardiac sympathetic innervation was determined using Iodine-123-metaiodobenzylguanidine (123-I-MIBG) scanning. Heart to mediastinal uptake ratio (H:M) were determined for early and late uptake on planar scintigraphy at 20 minutes and 3 hours following intravenous injection of 123-I-MIBG. Forty-two subjects: carotid sinus syndrome (n = 21), asymptomatic carotid sinus hypersensitivity (n = 12) and no carotid sinus hypersensitivity (n = 9) were included. Compared to the non- carotid sinus hypersensitivity control group, the carotid sinus syndrome group had significantly higher early H:M (estimated mean difference, B = 0.40; 95% confidence interval, CI = 0.13 to 0.67, p = 0.005) and late H:M (B = 0.32; 95%CI = 0.03 to 0.62, p = 0.032). There was, however, no significant difference in early H:M (p = 0.326) or late H:M (p = 0.351) between the asymptomatic carotid sinus hypersensitivity group and non- carotid sinus hypersensitivity controls. Cardiac sympathetic neuronal activity is increased relative to age-matched controls in individuals with carotid sinus syndrome but not those with asymptomatic carotid sinus hypersensitivity. Blood pressure and heart rate measurements alone may therefore represent an over simplification in the assessment for carotid sinus syndrome and the relative increase in cardiac sympathetic innervation provides additional clues to

Transgene delivery to endothelial cultures derived from porcine carotid artery ex vivo.

PubMed

Andoh, J; Sawyer, B; Szewczyk, K; Nortley, M; Rossetti, T; Loftus, I M; Yáñez-Muñoz, R J; Hainsworth, A H

2013-10-01

Carotid artery disease is a widespread cause of morbidity and mortality. Porcine models of vascular disease are well established in vivo, but existing endothelial systems in vitro (e.g. human umbilical vein endothelial cells, rat aortic endothelial cultures) poorly reflect carotid endothelium. A reliable in vitro assay would improve design of in vivo experiments and allow reduction and refinement of animal use. This study aimed (1) to develop ex vivo endothelial cultures from porcine carotid and (2) to test whether these were suitable for lentivector-mediated transgene delivery. Surplus carotid arteries were harvested from young adult female Large White pigs within 10 min post-mortem. Small sectors of carotid artery wall (approximately 4 mm×4 mm squares) were immobilised in a stable gel matrix. Cultures were exposed to HIV-derived lentivector (LV) encoding a reporter transgene or the equivalent integration-deficient vector (IDLV). After 7-14 days in vitro, cultures were fixed and labelled histochemically. Thread-like multicellular outgrowths were observed that were positive for endothelial cell markers (CD31, VEGFR2, von Willebrand factor). A minority of cells co-labelled for smooth muscle markers. Sensitivity to cytotoxic agents (paclitaxel, cycloheximide, staurosporine) was comparable to that in cell cultures, indicating that the gel matrix permits diffusive access of small pharmacological molecules. Transgene-expressing cells were more abundant following exposure to LV than IDLV (4.7, 0.1% of cells, respectively). In conclusion, ex vivo adult porcine carotid artery produced endothelial cell outgrowths that were effectively transduced by LV. This system will facilitate translation of novel therapies to clinical trials, with reduction and refinement of in vivo experiments.

Hybrid treatment of tandem, common carotid/innominate artery and ipsilateral carotid bifurcation stenoses by simultaneous, retrograde proximal stenting and eversion carotid endarterectomy: Preliminary results of a case series.

PubMed

Illuminati, Giulio; Pizzardi, Giulia; Pasqua, Rocco; Frezzotti, Francesca; Palumbo, Piergaspare; Macrina, Francesco; Calio', Francesco

2018-04-01

Tandem stenoses of the internal carotid artery (ICA) and proximal, ipsilateral common carotid artery (CCA) or innominate artery can be treated with a hybrid approach, combining conventional carotid endarterectomy (CEA) and retrograde stenting of the proximal stenosis, through surgical exposure of the carotid bifurcation. The purpose of this study was to evaluate the results of combining eversion CEA with retrograde CCA/innominate artery stenting. From January 2015 to July 2017, 7 patients, 6 men of a mean age of 72 years (range 59-83 years) underwent simultaneous, retrograde stenting of the proximal CCA/innominate artery and an eversion CEA of the ipsilateral ICA, through surgical exposure of the carotid bifurcation, for severe tandem stenoses. The proximal stenosis involved the left proximal CCA in 4 patients, the proximal innominate artery in 2 patients and the right CCA in one patient. The procedure was performed under general anesthesia in a conventional operating room equipped with a mobile C-arm. A covered, balloon expandable stent was deployed over the proximal stenosis via a 6-F sheath directly introduced into the proximal CCA through the obliquely transected carotid bulb. After removing the sheath, debris were flushed through the carotid bulb and eversion CEA completed the procedure. Study endpoints were: postoperative stroke/mortality rate, cardiac mortality and morbidity, peripheral nerve injury, cervical hematoma, overall late survival, freedom from ipsilateral stroke and patency of arterial reconstruction. No postoperative mortality or neurologic morbidity was observed in any patient. Cervical hematomas and peripheral nerve injuries were likewise absent. At a mean follow-up of 18 months, all the patients were alive, free from neurologic events of new onset and free from restenosis. Combined proximal stenting and eversion CEA for tandem lesions seems a valid treatment, with the advantages of eversion CEA over other techniques of carotid bifurcation

An ischemic stroke patient with free floating thrombus in carotid artery, successfully treated by open carotid thrombectomy: a first case report in Nepal.

PubMed

Shrestha, Prabin; Adhikari, Rupendra; Tamrakar, Samantha; Pant, Basanta; Koirala, Bhagwan; Yamaguchi, Satoshi; Kurisu, Kaoru

2012-12-01

Free floating thrombus in the carotid artery is a well-known phenomenon, though relatively rare. We present a case in which we performed open surgery and achieved successful retrieval of the thrombus. A 40 year-old male patient presented with ischemic stroke and mild left hemiparesis. Computerized tomography and magnetic resonance imaging showed infarction in the right parieto-occipital area. Carotid Doppler study showed carotid stenosis on the right side. Further investigation with CT angiography of the neck vessels confirmed significant carotid artery occlusion with a free-floating thrombus in the internal carotid artery. Carotid endarterectomy was planned under EEG monitoring. The right carotid artery was exposed with a vertical incision along the medial margin of the sternocleido-mastoid muscle. The carotid artery was opened and, as expected, showed a soft, mobile thrombus. Thus thrombectomy was planned. A 2 Fr fogarty catheter was introduced distal to the thrombus, the balloon was inflated and pulled back gently, which removed the thrombus completely. There was no postoperative complication and the patient is fine at 1 year follow-up.

Symptomatic and asymptomatic carotid artery plaque

PubMed Central

Mughal, Majid M; Khan, Mohsin K; DeMarco, J Kevin; Majid, Arshad; Shamoun, Fadi; Abela, George S

2011-01-01

Carotid atherosclerotic plaques represent both stable and unstable atheromatous lesions. Atherosclerotic plaques that are prone to rupture owing to their intrinsic composition such as a large lipid core, thin fibrous cap and intraplaque hemorrhage are associated with subsequent thromboembolic ischemic events. At least 15–20% of all ischemic strokes are attributable to carotid artery atherosclerosis. Characterization of plaques may enhance the understanding of natural history and ultimately the treatment of atherosclerotic disease. MRI of carotid plaque and embolic signals during transcranial Doppler have identified features beyond luminal stenosis that are predictive of future transient ischemic attacks and stroke. The value of specific therapies to prevent stroke in symptomatic and asymptomatic patients with severe carotid artery stenosis are the subject of current research and analysis of recently published clinical trials that are discussed in this article. PMID:21985544

Heritability of carotid intima-media thickness: a twin study.

PubMed

Zhao, Jinying; Cheema, Faiz A; Bremner, J Douglas; Goldberg, Jack; Su, Shaoyong; Snieder, Harold; Maisano, Carisa; Jones, Linda; Javed, Farhan; Murrah, Nancy; Le, Ngoc-Anh; Vaccarino, Viola

2008-04-01

To estimate the heritability of carotid intima-media thickness (IMT), a surrogate marker for atherosclerosis, independent of traditional coronary risk factors. We performed a classical twin study of carotid IMT using 98 middle-aged male twin pairs, 58 monozygotic (MZ) and 40 dizygotic (DZ) pairs, from the Vietnam Era Twin Registry. All twins were free of overt cardiovascular disease. Carotid IMT was measured by ultrasound. Bivariate and multivariate analyses were used to determine the association between traditional cardiovascular risk factors and carotid IMT. Intraclass correlation coefficients and genetic modeling techniques were used to determine the relative contributions of genes and environment to the variation in carotid IMT. In our sample, the mean of the maximum carotid IMT was 0.75+/-0.11. Age, systolic blood pressure and HDL were significantly associated with carotid IMT. The intraclass correlation coefficient for carotid IMT was larger in MZ (0.66; 95% confidence interval [CI], 0.62-0.69) than in DZ twins (0.37; 95% CI, 0.29-0.44), and the unadjusted heritability was 0.69 (95% CI, 0.54-0.79). After adjusting for traditional coronary risk factors, the heritability of carotid IMT was slightly reduced but still of considerable magnitude (0.59; 95% CI, 0.39-0.73). Genetic factors have a substantial influence on the variation of carotid IMT. Most of this genetic effect occurs through pathways independent of traditional coronary risk factors.

Heritability of Carotid Intima-Media Thickness: A Twin Study

PubMed Central

Zhao, Jinying; Cheema, Faiz A.; Bremner, J. Douglas; Goldberg, Jack; Su, Shaoyong; Snieder, Harold; Maisano, Carisa; Jones, Linda; Javed, Farhan; Murrah, Nancy; Le, Ngoc-Anh; Vaccarino, Viola

2008-01-01

Objective To estimate the heritability of carotid intima-media thickness (IMT), a surrogate marker for atherosclerosis, independent of traditional coronary risk factors. Methods and Results We performed a classical twin study of carotid IMT using 98 middle-aged male twin pairs, 58 monozygotic (MZ) and 40 dizygotic (DZ) pairs, from the Vietnam Era Twin Registry. All twins were free of overt cardiovascular disease. Carotid IMT was measured by ultrasound. Bivariate and multivariate analyses were used to determine the association between traditional cardiovascular risk factors and carotid IMT. Intraclass correlation coefficients and genetic modeling techniques were used to determine the relative contributions of genes and environment to the variation in carotid IMT. In our sample, the mean of the maximum carotid IMT was 0.75 ± 0.11. Age, systolic blood pressure and HDL were significantly associated with carotid IMT. The intraclass correlation coefficient for carotid IMT was larger in MZ (0.66; 95% confidence interval [CI], 0.62–0.69) than in DZ twins (0.37; 95% CI, 0.29–0.44), and the unadjusted heritability was 0.69 (95% CI, 0.54–0.79). After adjusting for traditional coronary risk factors, the heritability of carotid IMT was slightly reduced but still of considerable magnitude (0.59; 95% CI, 0.39–0.73). Conclusion Genetic factors have a substantial influence on the variation of carotid IMT. Most of this genetic effect occurs through pathways independent of traditional coronary risk factors. PMID:17825306

Early control of distal internal carotid artery during carotid endarterectomy: does it reduce cerebral microemboli?

PubMed

Mommertz, G; Das, M; Langer, S; Koeppel, T A; Krings, T; Mess, W H; Schiefer, J; Jacobs, M J

2010-06-01

According to the results of the large trials on carotid endarterectomy (CEA), this type of surgery is only warranted if perioperative mortality and morbidity are kept considerably low. Less attention has been paid to methods of cerebral protection during CEA, although intraoperative transcranial Doppler (TCD) can visualise intracerebral microemboli (MES) during routine carotid dissection, although MES occur throughout the CEA, only those during dissection are related to neurological outcome. Prevention of MES by means of early control of the distal internal carotid artery dislodging from the carotid artery plaque during dissection is very likely the mechanism behind an eventual benefit from this approach. Hence, the amount of MES might serve as a surrogate parameter for the risk of periprocedural neurological events. So, the aim of the present study was to evaluate whether early control of the distal carotid artery during CEA is capable of reducing the number of MES by means of a prospective randomised trial. Twenty-eight patients (29 procedures) could be prospectively included in our study. Before surgery we randomly assigned the patients to two groups: group A (N.=12): CEA by means of early control of the distal internal carotid artery; group B (N.=17): CEA with dissection of the total carotid bifurcation before clamping the arteries. Periprocedurally, we continuously monitored the cerebral blood flow in the ipsilateral middle cerebral artery by means of TCD. Pre- and postoperative morbidity were independently verified by a neurologist <2 days before and not later than five days after the procedure. Values of microembolic signs during dissection were summarised with arithmetic means and standard deviations. For further analysis non parametric Wilcoxon test was performed between both methods. P-values <0.05 were considered as statistically significant. Wilcoxon test was performed to compare both methods concerning clamp- and procedure times. We performed EEA 26

Surgical Exposure to Control the Distal Internal Carotid Artery at the Base of the Skull during Carotid Aneurysm Repair.

PubMed

Davis, Laura; Zeitouni, Anthony; Makhoul, Nicholas; Steinmetz, Oren K

2016-07-01

Extracranial carotid artery aneurysms are rare. Treatment options for these lesions include endovascular interventions, such as coiling and stenting, or surgical reconstruction, such as resection and primary reanastomosis, or interposition bypass grafting. In this report, we describe the surgical technique used to perform surgical repair of an internal carotid artery aneurysm extending up to the base of the skull. Anterior exposure of the infratemporal fossa and distal control of the carotid artery at the level of the carotid canal was achieved through a transcervical approach, performing double mandibular osteotomies with superior reflection of the middle mandibular section. Copyright © 2016 Elsevier Inc. All rights reserved.

Stent-protected carotid angioplasty using a membrane stent: a comparative cadaver study.

PubMed

Müller-Hülsbeck, Stefan; Gühne, Albrecht; Tsokos, Michael; Hüsler, Erhard J; Schaffner, Silvio R; Paulsen, Friedrich; Hedderich, Jürgen; Heller, Martin; Jahnke, Thomas

2006-01-01

To evaluate the performance of a prototype membrane stent, MembraX, in the prevention of acute and late embolization and to quantify particle embolization during carotid stent placement in human carotid explants in a proof of concept study. Thirty human carotid cadaveric explants (mild stenoses 0-29%, n = 23; moderate stenoses 30-69%, n = 3; severe stenoses 70-99%, n = 2) that included the common, internal and external carotid arteries were integrated into a pulsatile-flow model. Three groups were formed according to the age of the donors (mean 58.8 years; sample SD 15.99 years) and randomized to three test groups: (I) MembraX, n = 9; (II) Xpert bare stent, n = 10; (III) Xpert bare stent with Emboshield protection device, n = 9. Emboli liberated during stent deployment (step A), post-dilatation (step B), and late embolization (step C) were measured in 100 microm effluent filters. When the Emboshield was used, embolus penetration was measured during placement (step D) and retrieval (step E). Late embolization was simulated by compressing the area of the stented vessel five times. Absolute numbers of particles (median; >100 microm) caught in the effluent filter were: (I) MembraX: A = 7, B = 9, C = 3; (II) bare stent: A = 6.5, B = 6, C = 4.5; (III) bare stent and Emboshield: A = 7, B = 7, C.=.5, D = 8, E = 10. The data showed no statistical differences according to whether embolic load was analyzed by weight or mean particle size. When summing all procedural steps, the Emboshield caused the greatest load by weight (p = 0.011) and the largest number (p = 0.054) of particles. On the basis of these limited data neither a membrane stent nor a protection device showed significant advantages during ex vivo carotid angioplasty. However, the membrane stent seems to have the potential for reducing the emboli responsible for supposed late embolization, whereas more emboli were observed when using a protection device. Further studies are necessary and warranted.

Stent-Protected Carotid Angioplasty Using a Membrane Stent: A Comparative Cadaver Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mueller-Huelsbeck, Stefan, E-mail: muehue@rad.uni-kiel.de; Guehne, Albrecht; Tsokos, Michael

2006-08-15

Purpose. To evaluate the performance of a prototype membrane stent, MembraX, in the prevention of acute and late embolization and to quantify particle embolization during carotid stent placement in human carotid explants in a proof of concept study. Methods. Thirty human carotid cadaveric explants (mild stenoses 0-29%, n = 23; moderate stenoses 30-69%, n = 3; severe stenoses 70-99%, n = 2) that included the common, internal and external carotid arteries were integrated into a pulsatile-flow model. Three groups were formed according to the age of the donors (mean 58.8 years; sample SD 15.99 years) and randomized to three testmore » groups: (I) MembraX, n 9; (II) Xpert bare stent, n = 10; (III) Xpert bare stent with Emboshield protection device, n = 9. Emboli liberated during stent deployment (step A), post-dilatation (step B), and late embolization (step C) were measured in 100 {mu}m effluent filters. When the Emboshield was used, embolus penetration was measured during placement (step D) and retrieval (step E). Late embolization was simulated by compressing the area of the stented vessel five times. Results. Absolute numbers of particles (median; >100 {mu}m) caught in the effluent filter were: (I) MembraX: A = 7, B = 9, C = 3; (II) bare stent: A 6.5, B = 6, C = 4.5; (III) bare stent and Emboshield: A = 7, B = 7, C.=.5, D = 8, E = 10. The data showed no statistical differences according to whether embolic load was analyzed by weight or mean particle size. When summing all procedural steps, the Emboshield caused the greatest load by weight (p 0.011) and the largest number (p = 0.054) of particles. Conclusions. On the basis of these limited data neither a membrane stent nor a protection device showed significant advantages during ex vivo carotid angioplasty. However, the membrane stent seems to have the potential for reducing the emboli responsible for supposed late embolization, whereas more emboli were observed when using a protection device. Further studies are

Sympathetic Chain Schwannoma Resembling Carotid Body Tumour.

PubMed

Najeeb, Tallat; Khan, Musaddiq

2016-06-01

Schwannomas are rare, benign nerve sheath tumours of parapharyngeal space. Differential diagnosis should include salivary gland tumours, paragangliomas, neurofibromas, and metastatic lymph nodes. The tumours may arise from vagus nerve and cervical sympathetic chain (CSC). Diagnosis is usually made by imaging techniques: contrast CT, magnetic resonance imaging (MRI), and magnetic resonance angiography (MRA). Fine needle aspiration cytology (FNAC) is useful diagnostic procedure but poor results are seen in neurogenic tumours. Rarely, a vascular CSC schwannoma at the level of carotid arteries bifurcation may mimic carotid body tumour (CBT) on imaging techniques, especially if they are vascular, causing splaying of internal and external carotid arteries. Clinically patient was asymptomatic except for a pulsatile swelling in neck for 5 years. The presented case resembled CBTclinically, on ultrasound and on imaging techniques causing splaying of carotid arteries. FNAC was inconclusive and was always hemorrhagic. During operation, it was found to be CSC schwannoma just posterior to carotid body. CSC was sacrificed and patient developed Horner syndrome postoperatively.

Accuracy of Carotid Duplex Criteria in Diagnosis of Significant Carotid Stenosis in Asian Patients.

PubMed

Dharmasaroja, Pornpatr A; Uransilp, Nattaphol; Watcharakorn, Arvemas; Piyabhan, Pritsana

2018-03-01

Extracranial carotid stenosis can be diagnosed by velocity criteria of carotid duplex. Whether they are accurately applied to define severity of internal carotid artery (ICA) stenosis in Asian patients needs to be proved. The purpose of this study was to evaluate the accuracy of 2 carotid duplex velocity criteria in defining significant carotid stenosis. Carotid duplex studies and magnetic resonance angiography were reviewed. Criteria 1 was recommended by the Society of Radiologists in Ultrasound; moderate stenosis (50%-69%): peak systolic velocity (PSV) 125-230 cm/s, diastolic velocity (DV) 40-100 cm/s; severe stenosis (>70%): PSV greater than 230 cm/s, DV greater than 100 cm/s. Criteria 2 used PSV greater than 140 cm/s, DV less than 110 cm/s to define moderate stenosis (50%-75%) and PSV greater than 140 cm/s, DV greater than 110 cm/s for severe stenosis (76%-95%). A total of 854 ICA segments were reviewed. There was moderate stenosis in 72 ICAs, severe stenosis in 50 ICAs, and occlusion in 78 ICAs. Criteria 2 had slightly lower sensitivity, whereas higher specificity and accuracy than criteria 1 were observed in detecting moderate stenosis (criteria 1: sensitivity 95%, specificity 83%, accuracy 84%; criteria 2: sensitivity 92%, specificity 92%, and accuracy 92%). However, in detection of severe ICA stenosis, no significant difference in sensitivity, specificity, and accuracy was found (criteria 1: sensitivity 82%, specificity 99.57%, accuracy 98%; criteria 2: sensitivity 86%, specificity 99.68%, and accuracy 99%). In the subgroup of moderate stenosis, the criteria using ICA PSV greater than 140 cm/s had higher specificity and accuracy than the criteria using ICA PSV 125-230 cm/s. However, there was no significant difference in detection of severe stenosis or occlusion of ICA. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

21 CFR 870.3850 - Carotid sinus nerve stimulator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carotid sinus nerve stimulator. 870.3850 Section... nerve stimulator. (a) Identification. A carotid sinus nerve stimulator is an implantable device used to decrease arterial pressure by stimulating Hering's nerve at the carotid sinus. (b) Classification. Class...

Should patients with asymptomatic significant carotid stenosis undergo simultaneous carotid and cardiac surgery?

PubMed Central

Ogutu, Peter; Werner, Raphael; Oertel, Frank; Beyer, Michael

2014-01-01

A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether patients with severe asymptomatic carotid and coronary artery diseases should undergo simultaneous carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG). A total of 624 papers were found using the reported search, of which 20 represent the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study results of these papers are tabulated. Previous cohort studies showed mixed results, while advocating for the necessity of a randomized controlled trial (RCT). A recent RCT showed that patients undergoing prophylactic or simultaneous CEA + CABG had lower rates of stroke (0%) compared with delayed CEA 1–3 months after CABG (7.7%), without significant perioperative mortality difference. This study included patients with unilateral severe (>70%) asymptomatic carotid stenosis requiring CABG. An earlier partly randomized trial also showed better outcomes for patients undergoing simultaneous procedures (P = 0.045). Interestingly, systematic reviews previously failed to show compelling evidence supporting prophylactic CEA. This could be partly due to the fact that these reviews collectively analyse different cohort qualities. Neurological studies have, however, shown reduced cognitive and phonetic quality and function in patients with unilateral and bilateral asymptomatic carotid artery stenosis. Twenty-one RCTs comparing lone carotid artery stenting (CAS) and CEA informed the American Heart Association guidelines, which declared CAS comparable with CEA for symptomatic and asymptomatic carotid stenosis (CS). However, the risk of death/stroke for CAS alone is double that for CEA alone in the acute phase following onset of symptoms, while CEA alone is associated with a doubled risk of myocardial infarction. There is

Clinical Significance of the Champagne Bottle Neck Sign in the Extracranial Carotid Arteries of Patients with Moyamoya Disease.

PubMed

Yasuda, C; Arakawa, S; Shimogawa, T; Kanazawa, Y; Sayama, T; Haga, S; Morioka, T

2016-05-26

The champagne bottle neck sign represents a rapid reduction in the extracranial ICA diameters and is a characteristic feature of Moyamoya disease. However, the clinical significance of the champagne bottle neck sign is unclear. We investigated the relationship between the champagne bottle neck sign and the clinical and hemodynamic stages of Moyamoya disease. We analyzed 14 patients with Moyamoya disease before revascularization (5 men, 9 women; age, 43.2 ± 19.3 years). The ratio of the extracranial ICA and common carotid artery diameters was determined using carotid ultrasonography or cerebral angiography; a ratio of < 0.5 was considered champagne bottle neck sign-positive. The clinical disease stage was determined using the Suzuki angiographic grading system. CBF and cerebral vasoreactivity also were measured. The ICA/common carotid artery ratio (expressed as median [interquartile range]) decreased as the clinical stage advanced (stages I-II, 0.71 [0.60-0.77]; stages III-IV, 0.49 [0.45-0.57]; stages V-VI, 0.38 [0.34-0.47]; P < .001). Lower ICA/common carotid artery ratio tended to occur in symptomatic versus asymptomatic arteries (0.47 [0.40-0.53] versus 0.57 [0.40-0.66], respectively; P = .06). Although the ICA/common carotid artery ratio was not related to cerebral perfusion, it decreased as cerebral vasoreactivity decreased (P < .01). All champagne bottle neck sign-positive arteries were classified as Suzuki stage ≥III, 73% were symptomatic, and 89% exhibited reduced cerebral vasoreactivity. In contrast, all champagne bottle neck sign-negative arteries were Suzuki stage ≤III, 67% were asymptomatic, and all showed preserved cerebral vasoreactivity. The champagne bottle neck sign was related to advanced clinical stage, clinical symptoms, and impaired cerebral vasoreactivity. Thus, detection of the champagne bottle neck sign might be useful in determining the clinical and hemodynamic stages of Moyamoya disease. © 2016 American Society of Neuroradiology.

Morphological changes in carotid arteries in stroke cases.

PubMed

Thapa, Guna Bahadur; Sundas, Alin; Rauniyar, Raj Kumar

2013-01-01

Majority of stroke is due to ischemic infarction and occurs in carotid artery territory. The extra cranial parts of carotid arteries are the common sites for the atherosclerotic plaque formation. Ultrasonography is the first line of investigation for screening of the carotid artery diseases to localize and characterize the plaques. Objective was to study the morphological changes in extra cranial part of carotid arteries in cases of ischemic infarction using Ultrasonography. It was an institution based prospective study and convenience sampling method was used. Computed Tomography proven ischemic infarct, lacunar infarction and transient ischemic infarction cases were included in the study. Fifty four cases were included in the study. Mean of Intimo-medial Complex Thickness was 0.89 mm and 0.88 mm in right and left side respectively. Sixty five percent cases had plaque in extra cranial part of carotid artery. Ninety three percent of plaque was found in and adjacent to the carotid bulb region. Ipsilateral plaque was found in 76% and 65% cases on right and left side respectively. Fifty three percent of cases had soft plaque. Majority of cases had less than 50% narrowing of the lumen diameter in term of cross-sectional area due to plaque. Thirteen (24%) cases had plaque in internal carotid artery. Carotid ultrasound can be used for screening of the asymptomatic but high-risk cases and following up of the symptomatic cases to plan for necessary management as required.

Rubeosis iridis as a sign of underlying carotid stenosis.

PubMed

Oller, Mar; Esteban, Carlos; Pérez, Paulina; Parera, M Àngels; Lerma, Rosa; Llagostera, Secundino

2012-12-01

Severe carotid stenosis may be associated with uncommon clinical symptoms. We report a case of ocular ischemic syndrome and subsequent rubeosis iridis due to a high-grade carotid stenosis. The patient recovered visual acuity and his normal iris coloring after carotid endarterectomy. Rubeosis iridis may be the only clinical sign associated with severe carotid stenosis, making it mandatory to rule out the presence of carotid narrowing when it is detected. Establishing an early diagnosis is essential to improve quality of life, prognosis, and patients' outcome. Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Assessing carotid atherosclerosis by fiber-optic multispectral photoacoustic tomography

NASA Astrophysics Data System (ADS)

Hui, Jie; Li, Rui; Wang, Pu; Phillips, Evan; Bruning, Rebecca; Liao, Chien-Sheng; Sturek, Michael; Goergen, Craig J.; Cheng, Ji-Xin

2015-03-01

Atherosclerotic plaque at the carotid bifurcation is the underlying cause of the majority of ischemic strokes. Noninvasive imaging and quantification of the compositional changes preceding gross anatomic changes within the arterial wall is essential for diagnosis of disease. Current imaging modalities such as duplex ultrasound, computed tomography, positron emission tomography are limited by the lack of compositional contrast and the detection of flow-limiting lesions. Although high-resolution magnetic resonance imaging has been developed to characterize atherosclerotic plaque composition, its accessibility for wide clinical use is limited. Here, we demonstrate a fiber-based multispectral photoacoustic tomography system for excitation of lipids and external acoustic detection of the generated ultrasound. Using sequential ultrasound imaging of ex vivo preparations we achieved ~2 cm imaging depth and chemical selectivity for assessment of human arterial plaques. A multivariate curve resolution alternating least squares analysis method was applied to resolve the major chemical components, including intravascular lipid, intramuscular fat, and blood. These results show the promise of detecting carotid plaque in vivo through esophageal fiber-optic excitation of lipids and external acoustic detection of the generated ultrasound. This imaging system has great potential for serving as a point-ofcare device for early diagnosis of carotid artery disease in the clinic.

The association of carotid cavernous fistula with Graves’ ophthalmopathy

PubMed Central

Celik, Ozlem; Buyuktas, Deram; Islak, Civan; Sarici, A Murat; Gundogdu, A Sadi

2013-01-01

Graves’ ophthalmopathy (GO) is one of the frequent manifestations of the disorder which is an inflammatory process due to fibroblast infiltration, fibroblast proliferation and accumulation of glycosaminoglycans. Eye irritation, dryness, excessive tearing, visual blurring, diplopia, pain, visual loss, retroorbital discomfort are the symptoms and they can mimic carotid cavernous fistulas. Carotid cavernous fistulas are abnormal communications between the carotid arterial system and the cavernous sinus. The clinical manifestations of GO can mimic the signs of carotid cavernous fistulas. Carotid cavernous fistulas should be considered in the differential diagnosis of the GO patients especially who are not responding to the standard treatment and when there is a unilateral or asymmetric eye involvement. Here we report the second case report with concurrent occurrence of GO and carotid cavernous fistula in the literature. PMID:23571267

Evidence HDAC9 genetic variant associated with ischaemic stroke increases risk via promoting carotid atherosclerosis

PubMed Central

Markus, Hugh S; Mäkelä, Kari-Matti; Bevan, Steve; Raitoharju, Emma; Oksala, Niku; Bis, Joshua C.; O’Donnell, Chris; Hainsworth, Atticus; Lehtimäki, Terho

2014-01-01

Background and purpose A novel association between a single nucleotide polymorphism (SNP) on chromosome 7p21.1 and large vessel ischaemic stroke, was recently identified. The most likely underlying gene is histone deacetylase 9 (HDAC9). The mechanism by which HDAC9 increases stroke risk is not clear; both vascular and neuronal mechanisms have been proposed. Methods We determined whether the lead SNPs were associated with asymptomatic carotid plaque (N=25179) and carotid intima-media thickness (N=31210) detected by carotid ultrasound in a meta-analysis of population based and community cohorts. Immunohistochemistry was used to determine whether HDAC9 was expressed in healthy human cerebral and systemic arteries. In the Tampere Vascular Study we determined whether HDAC9 mRNA expression was altered in carotid (N=29), abdominal aortic (N=15) and femoral (N=24) atherosclerotic plaques compared with control (left internal thoracic, N=28) arteries. Results Both SNPs (rs11984041 and rs2107595) were associated with common carotid IMT (rs2107595 p=0.0018) and with presence of carotid plaque (rs2107595 p=0.0022). In both cerebral and systemic arteries, HDAC9 labelling was seen in nuclei and cytoplasm of vascular smooth muscle cells, and in endothelial cells. HDAC9 expression was upregulated in carotid plaques compared to left internal thoracic controls (p=0.00000103). It was also up-regulated in aortic and femoral plaques compared to controls, with mRNA expression increased in carotid compared with femoral plaques (p=0.0038). Conclusions Our results are consistent with the 7p21.1 association acting via promoting atherosclerosis, and consistent with alterations in HDAC9 expression mediating this increased risk. Further studies in experimental models are required to confirm this link. PMID:23449258

Stent-induced flow disturbances in the ipsilateral external carotid artery following internal carotid artery stenting: a temporary cause of jaw claudication.

PubMed

Giurgea, Georgiana-Aura; Haumer, Markus; Mlekusch, Irene; Sabeti-Sandor, Schila; Dick, Petra; Schillinger, Martin; Minar, Erich; Mlekusch, Wolfgang

2017-07-01

We hypothesize that stenting of the internal carotid artery can immediately impede blood flow to the external carotid artery by either plaque shift or stent coverage of the ostium, and thereby cause ischemic symptoms like ipsilateral jaw claudication. Thirty-three patients with high-grade asymptomatic stenosis of the internal carotid artery who underwent endovascular treatment were examined by ultrasound of the external carotid artery and performed an exercise test by chewing chewing gum synchronously to an electronic metronome for 3 min. Tests were performed before, the day after, and 1 week after the stenting procedure. Claudication time was defined as the timespan until occurrence of pain of the masseter muscle and/or chewing dyssynchrony to the metronome for more than 15 s. Ten patients with an isolated, atherosclerotic stenosis of the external carotid artery served as controls. A significantly reduced claudication time (in seconds) was recorded in patients who underwent carotid artery stenting compared to baseline values; median 89 (interquartile range, IQR, 57 to 124) vs. median 180 (IQR 153 to 180; p < 0.001). By categorization of the flow velocity at the external carotid artery into faster or slower as 200 cm/sec, the effect was even accentuated. Stenting values showed improvement 1 week after but did not return to baseline levels. No respective changes were found in controls. Stenting of the internal carotid artery lead to ipsilateral flow deterioration at the external carotid artery resulting in temporary jaw claudication. This impairment attenuated over the time and was significantly reduced after 1 week.

Imaging of the carotid space.

PubMed

Kuwada, Clinton; Mannion, Kyle; Aulino, Joseph M; Kanekar, Sangam G

2012-12-01

The most common of the lesions in the carotid space are discussed in relation to their radiographic diagnosis and clinical implications. The appearance of tumors and lesions on computed tomography or magnetic resonance imaging is presented, and their differential diagnosis is discussed. The image of each carotid disease is presented, and the discussion concludes with treatment recommendations and considerations. Copyright © 2012. Published by Elsevier Inc.

Retinal artery occlusion during carotid artery stenting with distal embolic protection device.

PubMed

Kohara, Kotaro; Ishikawa, Tatsuya; Kobayashi, Tomonori; Kawamata, Takakazu

2018-01-01

Retinal artery occlusion associated with carotid artery stenosis is well known. Although it can also occur at the time of carotid artery stenting, retinal artery occlusion via the collateral circulation of the external carotid artery is rare. We encountered two cases of retinal artery occlusion that were thought to be caused by an embolus from the external carotid artery during carotid artery stenting with a distal embolic protection device for the internal carotid artery. A 71-year-old man presented with central retinal artery occlusion after carotid artery stenting using the Carotid Guardwire PS and a 77-year-old man presented with branch retinal artery occlusion after carotid artery stenting using the FilterWire EZ. Because additional new cerebral ischaemic lesions were not detected in either case by postoperative diffusion-weighted magnetic resonance imaging, it was highly likely that the debris that caused retinal artery occlusion passed through not the internal carotid artery but collaterals to retinal arteries from the external carotid artery, which was not protected by a distal embolic protection device. It is suggested that a distal protection device for the internal carotid artery alone cannot prevent retinal artery embolisation during carotid artery stenting and protection of the external carotid artery is important to avoid retinal artery occlusion.

Inherent variations in CO-H2S-mediated carotid body O2 sensing mediate hypertension and pulmonary edema

PubMed Central

Peng, Ying-Jie; Makarenko, Vladislav V.; Nanduri, Jayasri; Vasavda, Chirag; Raghuraman, Gayatri; Yuan, Guoxiang; Gadalla, Moataz M.; Kumar, Ganesh K.; Snyder, Solomon H.; Prabhakar, Nanduri R.

2014-01-01

Oxygen (O2) sensing by the carotid body and its chemosensory reflex is critical for homeostatic regulation of breathing and blood pressure. Humans and animals exhibit substantial interindividual variation in this chemosensory reflex response, with profound effects on cardiorespiratory functions. However, the underlying mechanisms are not known. Here, we report that inherent variations in carotid body O2 sensing by carbon monoxide (CO)-sensitive hydrogen sulfide (H2S) signaling contribute to reflex variation in three genetically distinct rat strains. Compared with Sprague-Dawley (SD) rats, Brown-Norway (BN) rats exhibit impaired carotid body O2 sensing and develop pulmonary edema as a consequence of poor ventilatory adaptation to hypobaric hypoxia. Spontaneous Hypertensive (SH) rat carotid bodies display inherent hypersensitivity to hypoxia and develop hypertension. BN rat carotid bodies have naturally higher CO and lower H2S levels than SD rat, whereas SH carotid bodies have reduced CO and greater H2S generation. Higher CO levels in BN rats were associated with higher substrate affinity of the enzyme heme oxygenase 2, whereas SH rats present lower substrate affinity and, thus, reduced CO generation. Reducing CO levels in BN rat carotid bodies increased H2S generation, restoring O2 sensing and preventing hypoxia-induced pulmonary edema. Increasing CO levels in SH carotid bodies reduced H2S generation, preventing hypersensitivity to hypoxia and controlling hypertension in SH rats. PMID:24395806

Efficacy of different types of self-expandable stents in carotid artery stenting for carotid bifurcation stenosis.

PubMed

Liu, Ya-min; Qin, Hao; Zhang, Bo; Wang, Yu-jing; Feng, Jun; Wu, Xiang

2016-02-01

Both open and closed loop self-expandable stents were used in carotid artery stenting (CAS) for carotid bifurcation stenosis. We sought to compare the efficacy of two types of stents in CAS. The data of 212 patients treated with CAS (42 and 170 cases implanted with closed and open loop stents, respectively) for carotid bifurcation stenosis and distal filtration protection devices were retrospectively analyzed. Between closed and open loop stents, there were no significant differences in hospitalization duration, NIHSS score before and after the treatment, stenosis at 12th month, and cumulative incidence of primary endpoint events within 30 days or from the 31st day to the 12th month; while there were significant differences in hemodynamic changes and rate of difficulty in recycling distal filtration protection devices. Use of open vs. closed loop stents for carotid bifurcation stenosis seems to be associated with similar incidence of complications, except for greater rate of hemodynamic changes and lower rate of difficulty in recycling the distal filtration protection devices.

Predictors of antegrade flow at internal carotid artery during carotid artery stenting with proximal protection.

PubMed

Harada, Kei; Kakumoto, Kosuke; Oshikata, Shogo; Fukuyama, Kozo

2018-06-01

Carotid artery stenting (CAS) with proximal occlusion effectively prevent distal cerebral embolism by flow arrest at internal carotid artery (ICA); however, the method can expose antegrade flow at ICA due to incomplete flow arrest. The aim of this study was to identify predictors of antegrade flow during CAS with proximal protection. We retrospectively analyzed clinical and angiographic data among 143 lesions treated with CAS with proximal protection by occluding the common carotid artery (CCA) and external carotid artery (ECA). Flow arrest or antegrade flow at ICA was confirmed by contrast injection during proximal protection. Antegrade flow at ICA was observed in 12 lesions (8.4%). Compared with lesions in which flow arrest of ICA was achieved, the diameter of the superior thyroid artery (STA) was significantly larger (2.4 ± 0.34 vs. 1.4 ± 0.68 mm, p < 0.001), and the rate of ECA branches other than the STA located 0-10 mm above the bifurcation was significantly higher (50 vs. 8.4%, p < 0.001). Results of multivariate analysis revealed that a diameter of the STA ≥ 2.3 mm (OR 44, 95% CI 8.1-237; p < 0.001) and ECA branches other than the STA located 0-10 mm above the bifurcation (OR 6.0, 95% CI 1.1-32; p = 0.036) were independent predictors of antegrade flow. Distal filter protection should be combined with proximal protection for the lesions with antegrade flow to prevent distal migration of the carotid debris.

Current global status of carotid artery stent placement.

PubMed

Wholey, M H; Wholey, M; Bergeron, P; Diethrich, E B; Henry, M; Laborde, J C; Mathias, K; Myla, S; Roubin, G S; Shawl, F; Theron, J G; Yadav, J S; Dorros, G; Guimaraens, J; Higashida, R; Kumar, V; Leon, M; Lim, M; Londero, H; Mesa, J; Ramee, S; Rodriguez, A; Rosenfield, K; Teitelbaum, G; Vozzi, C

1998-05-01

Our purpose was to review the current status of carotid artery stent placement throughout the world. Surveys were sent to major interventional centers in Europe, North and South America, and Asia. Information from peer-reviewed journals was also included and supplemented the survey. The survey asked various questions regarding the patients enrolled, procedure techniques, and results of carotid stenting, including complications and restenosis. Of the centers which were sent surveys, 24 responded. The total number of endovascular carotid stent procedures that have been performed worldwide to date included 2,048 cases, with a technical success of 98.6%. Complications that occurred during carotid stent placement or within a 30-day period following placement were recorded. Overall, there were 63 minor strokes, with a rate of occurrence of 3.08%. The total number of major strokes was 27, for a rate of 1.32%. There were 28 deaths within a 30-day postprocedure period, resulting in a mortality rate of 1.37%. Restenosis rates of carotid stenting have been 4.80% at 6 mo. Endovascular stent treatment of carotid artery atherosclerotic disease is growing as an alternative to vascular surgery, especially for patients that are at high risk for standard carotid endarterectomy. The periprocedural risks for major and minor strokes and death are generally acceptable at this early stage of development.

The role of contrast-enhanced ultrasound in imaging carotid arterial diseases.

PubMed

Clevert, Dirk A; Paprottka, Philipp; Sommer, Wieland H; Helck, Andreas; Reiser, Maximilian F; Zengel, Pamela

2013-06-01

The standard of care for the initial diagnosis of carotid artery bifurcation diseases is carotid duplex ultrasound. Carotid abnormalities or difficult examinations may represent a diagnostic challenge in patients with clinical symptoms as well as in the follow-up after carotid endarterectomy, carotid artery stenting or other interventions. A promising new method in the diagnosis and follow-up of pathologic carotid diseases is contrast-enhanced ultrasound (CEUS). In comparison with magnetic resonance imaging or computed tomography, the contrast agents used for CEUS remain within the vascular space and hence can be used to study vascular disease and could provide additional information on carotid arterial diseases. This review describes the current carotid duplex ultrasound examination and compares the pathologic findings with CEUS. Copyright © 2013 Elsevier Inc. All rights reserved.

Microsurgical anatomy of the human carotid body (glomus caroticum): Features of its detailed topography, syntopy and morphology.

PubMed

Schulz, Sissy-Amelie; Wöhler, Aliona; Beutner, Dirk; Angelov, Doychin N

2016-03-01

The human glomus caroticum (GC) is not readily accessible during ordinary anatomical teaching courses because of insufficient time and difficulties encountered in the preparation. Accordingly, most anatomical descriptions of its location, relationship to neighboring structures, size and shape are supported only by drawings, but not by photographs. The aim of this study is to present the GC with all associated roots and branches. Following microscope-assisted dissection and precise photo-documentation, a detailed analysis of location, syntopy and morphology was performed. We carried out this study on 46 bifurcations of the common carotid artery (CCA) into the external (ECA) and internal (ICA) carotid arteries and identified the GC in 40 (91%) of them. We found significant variations regarding the location of the GC and its syntopy: GC was associated with CCA (42%), ECA (28%) and ICA (30%) lying on the medial or lateral surface (82% or 13%, respectively) or exactly in the middle (5%) of the bifurcation. The short and long diameter of its oval form varied from 1.0 × 2.0 to 5.0 × 5.0mm. Connections with the sympathetic trunk (100%), glossopharyngeal (93%), vagus (79%) and hypoglossal nerve (90%) could be established in 29 cadavers. We conclude that precise knowledge of this enormous variety might be very helpful not only to students in medicine and dentistry during anatomical dissection courses, but also to surgeons working in this field. Copyright © 2015 Elsevier GmbH. All rights reserved.

The relationship between heart-carotid pulse transit time and carotid intima-media thickness in hypertensive patients.

PubMed

Li, C; Xiong, H; Wu, W; Tian, X; Wang, Y; Wu, D; Lin, W-H; Miao, F; Zhang, H; Huang, W; Zhang, Y-T

2015-11-01

The study aimed to investigate the relationship between heart-carotid pulse transit time and carotid intima-media thickness (CIMT) in hypertensive patients, and whether including the pre-ejection period (PEP) in heart-carotid pulse transit time would affect this correlation. A total of 62 hypertensive patients were included in this study. They were divided into the normal CIMT group (n=33, CIMT⩽0.8 mm) and the thickened CIMT group (n=29, CIMT>0.8 mm). The noninvasive ultrasound method was used to measure CIMT, electrocardiogram R-wave-based heart-carotid pulse transit time (rcPTT) and PEP. Aortic valve-carotid artery pulse transit time (acPTT) was calculated by subtracting PEP from rcPTT. Simple linear analysis showed that CIMT was negatively associated with rcPTT and acPTT (r=-0.57, P<0.0001; r=-0.41, P=0.016) in the normal CIMT group as well as in the thickened CIMT group (r=-0.50, P=0.0053; r=-0.59, P=0.001). These relationships were eliminated in the normal CIMT group after adjusting for age, gender, smoking behaviour, systolic blood pressure, diastolic blood pressure and cholesterol levels. However, rcPTT and acPTT still showed significant correlations with CIMT in the thickened CIMT group. In conclusion, rcPTT and acPTT were associated with CIMT, independent of well-known clinical confounders in thickened CIMT hypertensive patients. Therefore, rcPTT and acPTT might be useful markers for atherosclerosis evaluation.

A randomized trial of decision-making in asymptomatic carotid stenosis.

PubMed

Silver, B; Zaman, I F; Ashraf, K; Majed, Y; Norwood, E M; Schuh, L A; Smith, B J; Smith, R E; Schultz, L R

2012-01-31

We sought to evaluate whether different presentation formats, presenter characteristics, and patient characteristics affect decision-making in asymptomatic carotid stenosis. Subjects included individuals presenting to a neurology clinic. Participants included those over age 18 without known carotid stenosis. Subjects were randomized to a 30-second video with 1 of 5 presentation formats (absolute risk, absolute event-free survival, annualized absolute risk, relative risk, and a qualitative description) delivered by 1 of 4 presenter physicians (black woman, white woman, black man, white man). Subjects then completed a one-page form regarding background demographics and their decision regarding treatment choice. A total of 409 subjects watched the video and completed the survey. Overall, 48.4% of subjects chose surgery. Presentation format strongly predicted choice of surgery (qualitative [64%], relative risk [63%], absolute risk [43%], absolute event-free survival [37%], and annualized absolute risk [35%], p < 0.001). There was a trend for younger age (mean age 52 vs 55, p = 0.054), male gender (53% vs 45%, p = 0.08), and advanced education (42% for high school education or less vs 52% for more than high school education, p = 0.052) to predict surgery choice. Gender and race of presenter, and race of subject, had no influence on the choice of treatment. Presentation format (information framing) strongly determines patient decision-making in asymptomatic carotid stenosis. Subject age, gender, and education level may also influence the decision. Clinicians should consider the influence of these variables when counseling patients.

Contralateral occlusion is not a clinically important reason for choosing carotid artery stenting for patients with significant carotid artery stenosis.

PubMed

Brewster, Luke P; Beaulieu, Robert; Kasirajan, Karthik; Corriere, Matthew A; Ricotta, Joseph J; Patel, Siddharth; Dodson, Thomas F

2012-11-01

Contralateral carotid artery occlusion by itself carries an increased risk of stroke. Carotid endarterectomy (CEA) in the presence of contralateral carotid artery occlusion has high reported rates of perioperative morbidity and mortality. Our objective was to determine if there is a clinical benefit to patients who receive carotid artery stenting (CAS) compared to CEA in the presence of contralateral carotid artery occlusion. We conducted a retrospective medical chart review over a 4.5-year institutional experience of persons with contralateral carotid artery occlusion and ipsilateral carotid artery stenosis who underwent CAS or CEA. The main outcome measures were 30-day cardiac, stroke, and mortality rate, and midterm mortality. Of a total of 713 patients treated for carotid artery stenosis during this time period, 57 had contralateral occlusion (~8%). Thirty-nine of these patients were treated with CAS, and 18 with CEA. The most common indications for CAS were prior neck surgery (18), contralateral internal carotid occlusion (nine), and prior neck radiation (seven). The average age was 70 ± 8.5 for CEA and 66.7 ± 9.3 for CAS (P = .20). Both groups were predominantly men (CEA 12 of 18; CAS 28 of 39; P = .76), with similar prevalence of symptomatic lesions (CEA 8 of 18, CAS 20 of 39; P = .77). Two patients died within 30 days in the CAS group (5%). No deaths occurred within 30 days in the CEA group (P = .50); the mortality rate for CAS and CEA combined was 3.5%. No perioperative strokes or myocardial infarction occurred in either group. Two transient ischemic attacks occurred after CAS. At mean follow-up of 29.4 ± 16 months (CEA) and 28 ± 14.4 months (CAS; range, 1.5-48.5 months), seven deaths occurred in the CAS group and one in the CEA group (17.9% vs 5.5%; P = .40). There were two reinterventions in the CAS group for in-stent restenosis and there were no reoperations in the CEA group. Although CEA and CAS can both be performed with good perioperative results

Carotid interventions and blood pressure.

PubMed

Hirschl, Mirko; Kundi, Michael

2014-12-01

Arterial baroreceptors are pressure sensors found in the carotid sinus near the bifurcation of the carotid artery and in the aortic arch. Carotid interventions, whether endovascular or surgical, affect this complicated control system and the post-interventional blood pressure behavior. Comparisons between the intervention techniques, however, are challenging due to the varying measurement methods, duration of observation, and patient populations. The question as to which interventional method is preferable, if undisturbed regulation of blood pressure is concerned, still remains unanswered. The fact that blood pressure events (i.e., hemodynamic instability, hypertension, unstable blood pressure) frequently occur both immediately after intervention and in the long term, mandates a particularly careful cardiopulmonary and blood pressure monitoring. Direct and indirect measurements of baroreceptor sensitivity can be helpful in identifying high-risk patients, although the association to hard clinical endpoints is rarely documented for methodological reasons.

Comparison of Neurocognitive Outcomes after Carotid Endarterectomy and Carotid Artery Stenting.

PubMed

Kim, Jerry J; Schwartz, Samuel; Wen, Johnny; deVirgilio, Christian; Lobue, Abeline; Walot, Irwin; Koopmann, Matthew; Donayre, Carlos; White, Rodney A

2015-10-01

Cognitive and emotional outcomes after carotid endarterectomy (CEA) and carotid artery stenting with embolic protection device (CAS + EPD) are not clear. Patients were entered prospectively into a United States Food and Drug Administration-approved single-center physician-sponsored investigational device exemption between 2004 and 2010 and received either CEA or CAS + EPD. Patients underwent cognitive testing preprocedure and at 6, 12, and 60 months postprocedure. Cognitive domains assessed included attention, memory, executive, motor function, visual spatial functioning, language, and processing speed. Beck Depression and anxiety scales were also compared. There were a total of 38 patients that met conventional indications for carotid surgery (symptomatic with ≥50% stenosis or asymptomatic with ≥70% stenosis)-12 patients underwent CEA, whereas 26 patients underwent CAS + EPD. Both CEA and CAS + EPD patients showed postprocedure improvement in memory and executive function. No differences were seen at follow-up in regards to emotional dysfunction (depression and anxiety), attention, visual spatial functioning, language, motor function, and processing speed. Only two patients underwent neuropsychiatric testing at 60 months-these CAS + EPD patients showed sustained improvement in memory, visual spatial, and executive functions. In conclusion, cognitive and emotional outcomes were similar between CEA and CAS + EPD patients.

Carotid artery disease following external cervical irradiation.

PubMed Central

Elerding, S C; Fernandez, R N; Grotta, J C; Lindberg, R D; Causay, L C; McMurtrey, M J

1981-01-01

A retrospective study of 910 patients surviving at least five years after cervical irradiation for Hodgkin's disease, non-Hodgkin's lymphoma, or primary head an neck neoplasms showed the incidence of stroke following cervical irradiation was 63 of 910 patients (6.3%) during a mean period of observation of nine years. This represents a trend toward an increased risk for this population observed over the same period of time (p = 0.39). A prospective study of 118 similar patients currently living five years after cervical radiotherapy was performed to determine the incidence of carotid artery disease occurring as a consequence of neck irradiation. Abnormal carotid phonangiograms (CPA) were found in 25% of the patients and abnormal oculoplethysmographs (OPG) were found in 17%. These studies represent significant carotid lesions that are not expected in such a population. It is concluded that the carotid stenoses demonstrated are most likely a consequence of prior irradiation. Patients that are five-year survivors of cervical irradiation should have noninvasive vascular laboratory studies performed as part of their routine follow-up examinations in order to detect these carotid lesions while they are occult. PMID:7294930

Mathematical model of carotid artery for stent placement

NASA Astrophysics Data System (ADS)

Rahman, Tengku Husna Tengku Abdul; Din, Ummul Khair Salma; Ahmad, Rokiah @ Rozita

2016-11-01

The carotid artery stenting is one of the methods used to reduce the effect of artherosclerosis which caused by the thickening of the artery wall. In most of the studies, the measure of wall elasticity, shear stress and the blood pressure through the blood flow were considered. The aim of this study is to determine the position to place the stent inside the carotid artery. A mathematical model is reconstructed to determine the suitable location of the stent in the carotid artery. Throughout the study, differences in fluid flow between a normal carotid artery wall and stenosed carotid artery wall are investigated. Since the existence of the stenosis provides a resistance in the flow, it is important to identify the right position to place the stent. The stent will be placed in the position where stenosis exists to ease the blood to flow normally. Later after the stent placement, the blood flow normally through the blood vessel.

The role of maxiK channels in carotid body chemotransduction.

PubMed

Peers, Chris; Wyatt, Christopher N

2007-07-01

MaxiK channels are a unique class of K(+) channels activated by both voltage and intracellular Ca(2+). Derived from a single gene, their diversity arises from extensive splicing, and their wide distribution has led to their implication in a large variety of cellular functions. In the carotid body, they have been proposed to contribute to the resting membrane potential of type I cells, and also to be O(2) sensitive. Thus, they have been suggested to have an important role in hypoxic chemotransduction. Their O(2) sensitivity is preserved when the channels are expressed in HEK 293 cells, permitting detailed studies of candidate mechanisms underlying hypoxic inhibition of maxiK channels. In this article, we review evidence for and against an important role for maxiK channels in chemotransduction. We also consider different mechanisms proposed to account for hypoxic channel inhibition and suggest that, although our understanding of this important physiological process has advanced significantly in recent years, there remain important, unanswered questions as to the importance of maxiK in carotid body chemoreception.

Results of subclavian to carotid artery bypass for occlusive disease of the common carotid artery: A retrospective cohort study.

PubMed

Illuminati, Giulio; Pizzardi, Giulia; Calio, Francesco G; Masci, Federica; Pasqua, Rocco; Frezzotti, Francesca; Peschillo, Simone

2018-05-01

Optimal treatment of significant atherosclerosis of the common carotid artery (CCA) is not well-defined. The purpose of this study was to evaluate the long-term results of prosthetic subclavian to carotid bypass for occlusive disease of the CCA. From January 1994 to December 2015, 45 patients, mean age 67 years, underwent an ipsilateral subclavian to carotid bypass for occlusive disease of the CCA. Thirty-eight patients (84%) presented with neurologic symptoms, including transitory ischemic attacks in 29 cases and minor strokes in 9 cases. The graft material consisted of a 7 mm polytetrafluoroethylene conduit, and the distal anastomosis was done on the carotid bulb in 21 patients, on the internal carotid artery in 19 cases, and on the distal CCA in 5 cases. Median length of follow-up was 58 months. Study endpoints were the combined postoperative stroke/mortality rate, graft infection, overall late survival, freedom from ipsilateral stroke, and graft patency. Postoperative stroke/mortality rate was 2%. No graft infection was observed throughout follow-up. At 60 months, overall survival, freedom from stroke, and graft patency were 71% (standard error [SE] = 0.07), 98% (SE = 0.02), and 95.5% (SE = 0.06), respectively. Subclavian to carotid bypass allows very good patency rates and excellent protection from postoperative and late stroke, remaining a benchmark for any other treatment method. Copyright © 2018. Published by Elsevier Ltd.

Endogenous Cholesterol Excretion Is Negatively Associated With Carotid Intima-Media Thickness in Humans.

PubMed

Lin, Xiaobo; Racette, Susan B; Ma, Lina; Wallendorf, Michael; Dávila-Román, Victor G; Ostlund, Richard E

2017-12-01

Epidemiological studies strongly suggest that lipid factors independent of low-density lipoprotein cholesterol contribute significantly to cardiovascular disease risk. Because circulating lipoproteins comprise only a small fraction of total body cholesterol, the mobilization and excretion of cholesterol from plasma and tissue pools may be an important determinant of cardiovascular disease risk. Our hypothesis is that fecal excretion of endogenous cholesterol is protective against atherosclerosis. Cholesterol metabolism and carotid intima-media thickness were quantitated in 86 nondiabetic adults. Plasma cholesterol was labeled by intravenous infusion of cholesterol-d 7 solubilized in a lipid emulsion and dietary cholesterol by cholesterol-d 5 and the nonabsorbable stool marker sitostanol-d 4 . Plasma and stool samples were collected while subjects consumed a cholesterol- and phytosterol-controlled metabolic kitchen diet and were analyzed by mass spectrometry. Carotid intima-media thickness was negatively correlated with fecal excretion of endogenous cholesterol ( r =-0.426; P <0.0001), total cholesterol ( r =-0.472; P ≤0.0001), and daily percent excretion of cholesterol from the rapidly mixing cholesterol pool ( r =-0.343; P =0.0012) and was positively correlated with percent cholesterol absorption ( r =+0.279; P =0.0092). In a linear regression model controlling for age, sex, systolic blood pressure, hemoglobin A1c, low-density lipoprotein, high-density lipoprotein cholesterol, and statin drug use, fecal excretion of endogenous cholesterol remained significant ( P =0.0008). Excretion of endogenous cholesterol is strongly, independently, and negatively associated with carotid intima-media thickness. The reverse cholesterol transport pathway comprising the intestine and the rapidly mixing plasma, and tissue cholesterol pool could be an unrecognized determinant of cardiovascular disease risk not reflected in circulating lipoproteins. Further work is needed to relate

Modern medical treatment with or without carotid endarterectomy for severe asymptomatic carotid atherosclerosis.

PubMed

Kolos, Igor; Troitskiy, Alexandr; Balakhonova, Tatiana; Shariya, Merab; Skrypnik, Denis; Tvorogova, Tatiana; Deev, Alexandr; Boytsov, Sergey

2015-10-01

This study assessed the value of modern medical treatment (MMT) with and without carotid endarterectomy (CEA) in patients with asymptomatic severe carotid artery stenosis. We conducted a randomized trial involving 55 patients with 70% to 79% carotid stenosis at three Russian centers. Between 2009 and 2013, 31 patients were randomized to undergo CEA with MMT (CEA group) and 24 to receive MMT alone. The primary end point was nonfatal ipsilateral stroke or death from any cause during a follow-up period of 5.0 years. The secondary end point was any nonfatal stroke, carotid revascularization, or death from any cause during follow-up. The trial was stopped after a median follow-up of 3.3 years (maximum, 5.0 years). There were two primary events in the CEA group and nine events in the MMT group. The 3.3-year cumulative primary event rates were 6.5% in the CEA group and 37.5% in the MMT group (hazard ratio for the MMT group, 5.06; 95% confidence interval, 1.53-16.79; P = .008). The 3.3-year cumulative secondary end point was 12.9% in the CEA group and 50.0% in the MMT group (hazard ratio for the MMT group, 4.23; 95% confidence interval, 1.55-11.53; P = .0048). CEA as an initial management strategy could reduce the risk of death and major cerebrovascular events when added to MMT. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Carotid Artery Stenting: Review of Technique and Update of Recent Literature

PubMed Central

Ahn, Sun Ho; Prince, Ethan A.; Dubel, Gregory J.

2013-01-01

Stroke is the fourth leading cause of death and the number one cause of long-term disability in the United States. Carotid stenosis is an important cause of ischemic strokes, accounting for 20 to 25%. Previous studies have established carotid endarterectomy as standard of care of symptomatic patients with > 50% stenosis and asymptomatic patients with > 60% stenosis; recently, carotid artery stenting has emerged as an alternative treatment for carotid stenosis. Several studies have been published comparing carotid artery stenting with endarterectomy with mixed results. In this article, the authors discuss carotid artery stenting technique, the results from the most recent trials, and future directions. PMID:24436551

Freehand three-dimensional ultrasound imaging of carotid artery using motion tracking technology.

PubMed

Chung, Shao-Wen; Shih, Cho-Chiang; Huang, Chih-Chung

2017-02-01

Ultrasound imaging has been extensively used for determining the severity of carotid atherosclerotic stenosis. In particular, the morphological characterization of carotid plaques can be performed for risk stratification of patients. However, using 2D ultrasound imaging for detecting morphological changes in plaques has several limitations. Due to the scan was performed on a single longitudinal cross-section, the selected 2D image is difficult to represent the entire morphology and volume of plaque and vessel lumen. In addition, the precise positions of 2D ultrasound images highly depend on the radiologists' experience, it makes the serial long-term exams of anti-atherosclerotic therapies are difficult to relocate the same corresponding planes by using 2D B-mode images. This has led to the recent development of three-dimensional (3D) ultrasound imaging, which offers improved visualization and quantification of complex morphologies of carotid plaques. In the present study, a freehand 3D ultrasound imaging technique based on optical motion tracking technology is proposed. Unlike other optical tracking systems, the marker is a small rigid body that is attached to the ultrasound probe and is tracked by eight high-performance digital cameras. The probe positions in 3D space coordinates are then calibrated at spatial and temporal resolutions of 10μm and 0.01s, respectively. The image segmentation procedure involves Otsu's and the active contour model algorithms and accurately detects the contours of the carotid arteries. The proposed imaging technique was verified using normal artery and atherosclerotic stenosis phantoms. Human experiments involving freehand scanning of the carotid artery of a volunteer were also performed. The results indicated that compared with manual segmentation, the lowest percentage errors of the proposed segmentation procedure were 7.8% and 9.1% for the external and internal carotid arteries, respectively. Finally, the effect of handshaking was

Imaging of the Fibrous Cap in Atherosclerotic Carotid Plaque

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saba, Luca, E-mail: lucasaba@tiscali.i; Potters, Fons; Lugt, Aad van der

2010-08-15

In the last two decades, a substantial number of articles have been published to provide diagnostic solutions for patients with carotid atherosclerotic disease. These articles have resulted in a shift of opinion regarding the identification of stroke risk in patients with carotid atherosclerotic disease. In the recent past, the degree of carotid artery stenosis was the sole determinant for performing carotid intervention (carotid endarterectomy or carotid stenting) in these patients. We now know that the degree of stenosis is only one marker for future cerebrovascular events. If one wants to determine the risk of these events more accurately, other parametersmore » must be taken into account; among these parameters are plaque composition, presence and state of the fibrous cap (FC), intraplaque haemorrhage, plaque ulceration, and plaque location. In particular, the FC is an important structure for the stability of the plaque, and its rupture is highly associated with a recent history of transient ischaemic attack or stroke. The subject of this review is imaging of the FC.« less

Endovascular Treatment of Iatrogenic and Traumatic Carotid Artery Dissection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schulte, Stefan; Donas, Konstantinos P., E-mail: k.donas@gmx.at; Pitoulias, Georgios A.

This paper reports on the early and midterm results of endovascular treatment of acute carotid artery dissections, its specific problems, and its limitations. We encountered seven patients with symptomatic extracranial carotid artery dissection, three cases of which occurred after carotid endarterectomy, two after carotid angioplasty and stenting, and two after trauma. Balloon-expandable and self-expanding stents were placed using a transfemoral approach. Success in restoring the carotid lumen was achieved in all patients. No procedure-related complications occurred. All patients experienced significant clinical improvement while in the hospital and achieved complete long-term recovery. At follow-up (mean, 22.4 months), good luminal patency ofmore » the stented segments was observed. In conclusion, in this small series, primary stent-supported angioplasty seems to be a safe and effective strategy in the treatment of selected patients having acute traumatic extracranial carotid artery dissection, with excellent early and midterm results. Larger series and longer-term follow-up are required before definitive recommendations can be made.« less

[Surgical Treatment of Cervical Carotid Artery Aneurysm].

PubMed

Hamasaki, Ryo; Yanagisawa, Toshiharu; Takahashi, Yusuke; Shimizu, Hiroaki

2017-08-01

Cervical carotid aneurysms are rare, and surgical treatment should be planned for each patient. The authors report 9 cases of cervical carotid aneurysm in 9 patients(mean age, 53.7 years;5 men)who were treated surgically between 2005 and 2014. The aneurysm was located in the internal carotid artery in 6 patients, the common carotid artery in 2 patients, and the carotid bifurcation in 1 patient. Four aneurysms were recurrences after a previous endovascular intervention(parent artery coil embolization, covered stent placement, or stent with coil embolization). The mean interval between the endovascular therapy and the onset of the present illness was 6 years. All the patients presented a mass effect at the neck, including lower cranial nerve dysfunction in 1 patient. Two patients presented with ischemic events presumably due to thromboembolism from the target aneurysms. Surgical treatments included local vascular reconstruction procedures in 6 patients(interposition vein or artificial graft bypass in 5 patients and in situ bypass in 1 patient). Four aneurysms were then resected. Two patients with rich collateral blood flow were treated with ligation of the parent artery proximal to the aneurysm. Surgical complications included embolic stroke and cranial nerve dysfunction in 2 patients, respectively, both presumably due to surgical manipulation. The modified Rankin scale(mRS)score at discharge was 0 in 5 patients, 1 in 1 patient, 2 in 2 patients, and 6 in 1 patient(vascular tumor). Surgical treatment of cervical carotid aneurysms seems a reasonable treatment of choice, but lower nerve dysfunction and embolism from the aneurysm should be avoided.

Regulation of Carotid Body Oxygen Sensing by Hypoxia-Inducible Factors

PubMed Central

Prabhakar, Nanduri R.; Semenza, Gregg L.

2015-01-01

Oxygen (O2) sensing by the carotid body and its chemosensory reflex is critical for homeostatic regulation of breathing and blood pressure. Carotid body responses to hypoxia are not uniform but instead exhibit remarkable inter-individual variations. The molecular mechanisms underlying variations in carotid body O2 sensing are not known. Hypoxia-inducible factor-1 (HIF-1) and HIF-2 mediate transcriptional responses to hypoxia. This article reviews the emerging evidence that proper expression of the HIF-α isoforms is a key molecular determinant for carotid body O2 sensing. HIF-1α deficiency leads to a blunted carotid body hypoxic response, which is due to increased abundance of HIF-2α, elevated anti-oxidant enzyme activity, and a reduced intracellular redox state. Conversely, HIF-2α deficiency results in augmented carotid body sensitivity to hypoxia, which is due to increased abundance of HIF-1α, elevated pro-oxidant enzyme activity, and an oxidized intracellular redox state. Double heterozygous mice with equally reduced HIF-1α and HIF-2α showed no abnormality in redox state or carotid body O2 sensing. Thus, mutual antagonism between HIF-α isoforms determines the redox state and thereby establishes the set point for hypoxic sensing by the carotid body. PMID:26265380

Progranulin expression in advanced human atherosclerotic plaque.

PubMed

Kojima, Yoji; Ono, Koh; Inoue, Katsumi; Takagi, Yasushi; Kikuta, Ken-ichiro; Nishimura, Masaki; Yoshida, Yoshinori; Nakashima, Yasuhiro; Matsumae, Hironobu; Furukawa, Yutaka; Mikuni, Nobuhiro; Nobuyoshi, Masakiyo; Kimura, Takeshi; Kita, Toru; Tanaka, Makoto

2009-09-01

Progranulin (PGRN) is a unique growth factor that plays an important role in cutaneous wound healing. It has an anti-inflammatory effect and promotes cell proliferation. However, when it is degraded to granulin peptides (GRNs) by neutrophil proteases, a pro-inflammatory reaction occurs. Since injury, inflammation and repair are common features in the progression of atherosclerosis, it is conceivable that PGRN plays a role in atherogenesis. Immunohistochemical analysis of human carotid endoatherectomy specimens indicated that vascular smooth muscle cells (vSMCs) in the intima expressed PGRN. Some macrophages in the plaque also expressed PGRN. We assessed the effect of PGRN on a human monocytic leukemia cell line (THP-1) and human aortic smooth muscle cells (HASMCs). PGRN alone had no effect on HASMC or THP-1 proliferation or migration. However, when THP-1 cells were stimulated with MCP-1, the number of migrated cells decreased in a PGRN-dose-dependent manner. TNF-alpha-induced HASMC migration was enhanced only at 10nM of PGRN. Interleukin-8 (IL-8) secretion from HASMCs was reduced by forced expression of PGRN and increased by RNAi-mediated knockdown of PGRN. While exogenous treatment with recombinant PGRN decreased IL-8 secretion, degraded recombinant GRNs increased IL-8 secretion from HASMCs. The expression of PGRN mainly reduces inflammation and its degradation into GRNs enhances inflammation in atherosclerotic plaque and may contribute to the progression of atherosclerosis.

Carotid artery surgery

MedlinePlus

... of stroke. Some of these medicines are aspirin, clopidogrel (Plavix), and warfarin (Coumadin). Carotid angioplasty and stenting is ... thinner drugs. These include aspirin, ibuprofen (Advil, Motrin), ... (Plavix), naprosyn (Aleve, Naproxen), and other drugs like ...

Optimal medical treatment versus carotid endarterectomy: the rationale and design of the Aggressive Medical Treatment Evaluation for Asymptomatic Carotid Artery Stenosis (AMTEC) study.

PubMed

Kolos, Igor; Loukianov, Mikhail; Dupik, Nikolay; Boytsov, Sergey; Deev, Alexandr

2015-02-01

Carotid endarterectomy and medical therapy (aspirin) were shown superior to medical therapy alone for asymptomatic (≥ 60%) carotid stenosis. The role of modern medical therapy (statins, antihypertensive treatment, and aspirin) in the treatment of such patients is undefined. Establishing the safety, efficacy, and durability of optimal medical therapy and lifestyle modification requires rigorous comparison with carotid endarterectomy in asymptomatic patients. The objective is to compare the efficacy of carotid endarterectomy + optimal medical therapy versus optimal medical therapy alone in patients with asymptomatic (70-79%) extracranial carotid stenosis. The Aggressive Medical Treatment Evaluation for Asymptomatic Carotid Artery Stenosis study is a prospective, randomized, parallel, two-arm, multicenter trial. Primary end-points will be analyzed using standard time-to-event statistical modeling with adjustment for major baseline covariates. The primary analysis is on an intent-to-treat basis. The primary outcome is nonfatal stroke, nonfatal myocardial infarction, and death during follow-up of up to five-years, and the secondary outcome includes death from any cause and stroke. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.

Subject-Specific Fully-Coupled and One-Way Fluid-Structure Interaction Models for Modeling of Carotid Atherosclerotic Plaques in Humans

PubMed Central

Tao, Xiaojuan; Gao, Peiyi; Jing, Lina; Lin, Yan; Sui, Binbin

2015-01-01

Background Hemodynamics play an important role in the development and progression of carotid atherosclerosis, and may be important in the assessment of plaque vulnerability. The aim of this study was to develop a system to assess the hemodynamics of carotid atherosclerotic plaques using subject-specific fluid-structure interaction (FSI) models based on magnetic resonance imaging (MRI). Material/Methods Models of carotid bifurcations (n=86 with plaques from 52 patients, n=14 normal carotids from 12 participants) were obtained at the Department of Radiology, Beijing Tian Tan Hospital between 2010 and 2013. The maximum von Mises stress, minimum pressure, and flow velocity values were assessed at the most stenotic site in patients, or at the carotid bifurcations in healthy volunteers. Results of one-way FSI were compared with fully-coupled FSI for the plaques of 19 randomly selected models. Results The maximum von Mises stress and the minimum pressure and velocity were significantly increased in the stenosis group compared with controls based on one-way FSI (all P<0.05). The maximum von Mises stress and the minimum pressure were significantly higher and the velocity was significantly lower based on fully coupled FSI compared with on-way FSI (all P<0.05). Although there were differences in numerical values, both methods were equivalent. The maximum von Mises stress of vulnerable plaques was significantly higher than stable plaques (P<0.001). The maximum von Mises stress of the group with fibrous cap defect was significantly higher than the group without fibrous cap defect (P=0.001). Conclusions The hemodynamics of atherosclerotic plaques can be assessed noninvasively using subject-specific models of FSI based on MRI. PMID:26510514

Management of penetrating carotid arterial injury.

PubMed Central

Liekweg, W G; Greenfield, L J

1978-01-01

A review of the experience with penetrating wounds to the carotid artery was undertaken in an effort to establish concise clinical criteria for surgical management. These results were compared with similar cases from the literature reported since 1963. In these 233 cases, the presence or absence of preoperative neurological deficits was correlated with vascular repair or ligation of the carotid artery. The presence of coma preoperatively was the single most influential factor in determining operative management and prognosis. Patients without a neurological defect should have restoration of vascular continuity (0% mortality, 0.6% morbidity), which produces significantly better results than carotid ligation (p less than 0.002). Patients with all grades of neurological deficit, short of coma, should also have primary vascular repair. Morbidity and mortality rates are significantly less than those following ligation (15 vs. 50%, p less than 0.05). In comatose patients, neither repair nor ligation appear to influence the poor prognosis. At the present time, ligation of the carotid artery is only indicated in the comatose patient who has no evidence of prograde flow or if repair is technically impossible. PMID:718284

A Novel Carotid Device for Embolic Diversion: Lessons Learned from a 'First in Man' Trial in Patients with Atrial Fibrillation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sievert, Horst, E-mail: info@cvcfrankfurt.de; Franke, Jennifer; Grad, Ygael

Purpose: This study was designed to investigate a novel device that was developed to direct emboli away from the internal carotid artery to the external carotid artery to prevent embolic stroke while avoiding the necessity for anticoagulation with warfarin. Methods: A stent-like, self-expandable filter was developed consisting of fine cobalt alloy mesh. After promising preclinical animal testing, the device was implanted into the common carotid artery extending into the external carotid artery in three patients with atrial fibrillation, each of whom were at high-risk for cerebral emboli and were suboptimal candidates for anticoagulation. Follow-up was performed clinically and with carotidmore » duplex ultrasound. Results: The implantation was successful in all three patients. Unrestricted flow through the filter was demonstrated in each patient at 6 months by duplex sonography. However, at 7 months ultrasound demonstrated occlusion of the internal carotid artery filter in one patient, which was subsequently confirmed by angiography. Subtotal filter occlusion occurred in a second patient at 14 months. Neither patient had clinical symptoms. Both internal carotid arteries were successfully recanalized using standard angioplasty techniques without complication. The third patient had completely normal carotid blood flow at 29 months follow-up. Conclusions: Implantation of a novel device intended to divert emboli away from the internal carotid artery was feasible, but resulted in occlusive neointimal proliferation in two of three patients. These results demonstrate a discrepancy from the findings of preclinical animal studies and human investigation.« less

[Endovascular treatment of carotid-cavernous fistula type A with platinium coils].

PubMed

Culafić, Slobodan; Juszkat, Robert; Rusović, Sinisa; Stefanović, Dara; Minić, Ljubodrag; Spaić, Milan

2008-12-01

Carotid-cavernous fistulas are abnormal communications between carotid arteries or their branches and the cavernous system caused mostly by trauma. Posttraumatic fistulas represent 70% of all carotid-cavernous fistulas and they are mostly high-flow shunts (type A). This type gives characteristic eye symptoms. This paper presents a 44-year old male patient with carotid-cavernous fistula as a result of penetrating head injury. In clinical presentation the patient had exophthalmos, conjunctival chemosis and weakening of vision on the right eye, headache and diplopia. Digital subtracted angiography showed high-flow carotid-cavernous fistula, which was vascularised from the left carotid artery and from vertebrobasilar artery. Endovascular embolization with platinum coils was performed through the transarterial route (endoarterial approach). Check angiogram confirmed that the fistula was closed and that no new communications developed. Embolization of complex carotid-cavernous fistula type A was successfully performed with platinum coils by endovascular approach.

Hydrocortisone supresses inflammatory activity of metalloproteinase-8 in carotid plaque.

PubMed

Gabriel, Sthefano Atique; Antonangelo, Leila; Capelozzi, Vera Luiza; Beteli, Camila Baumann; Camargo Júnior, Otacílio de; Aquino, José Luis Braga de; Caffaro, Roberto Augusto

2015-01-01

Matrix metalloproteinases are inflammatory biomarkers involved in carotid plaque instability. Our objective was to analyze the inflammatory activity of plasma and carotid plaque MMP-8 and MMP-9 after intravenous administration of hydrocortisone. The study included 22 patients with stenosis ≥ 70% in the carotid artery (11 symptomatic and 11 asymptomatic) who underwent carotid endarterectomy. The patients were divided into two groups: Control Group - hydrocortisone was not administered, and Group 1 - 500 mg intravenous hydrocortisone was administered during anesthetic induction. Plasma levels of MMP-8 and MMP-9 were measured preoperatively (24 hours before carotid endarterectomy) and at 1 hour, 6 hours and 24 hours after carotid endarterectomy. In carotid plaque, tissue levels of MMP-8 and MMP-9 were measured. Group 1 showed increased serum levels of MMP- 8 (994.28 pg/ml and 408.54 pg/ml, respectively; P=0.045) and MMP-9 (106,656.34 and 42,807.69 respectively; P=0.014) at 1 hour after carotid endarterectomy compared to the control group. Symptomatic patients in Group 1 exhibited lower tissue concentration of MMP-8 in comparison to the control group (143.89 pg/ml and 1317.36 respectively; P=0.003). There was a correlation between preoperative MMP-9 levels and tissue concentrations of MMP-8 (P=0.042) and MMP-9 (P=0.019) between symptomatic patients in the control group. Hydrocortisone reduces the concentration of MMP- 8 in carotid plaque, especially in symptomatic patients. There was an association between systemic and tissue inflammation.

Hydrocortisone supresses inflammatory activity of metalloproteinase - 8 in carotid plaque

PubMed Central

Gabriel, Sthefano Atique; Antonangelo, Leila; Capelozzi, Vera Luiza; Beteli, Camila Baumann; de Camargo Júnior, Otacílio; de Aquino, José Luis Braga; Caffaro, Roberto Augusto

2015-01-01

Objective Matrix metalloproteinases are inflammatory biomarkers involved in carotid plaque instability. Our objective was to analyze the inflammatory activity of plasma and carotid plaque MMP-8 and MMP-9 after intravenous administration of hydrocortisone. Methods The study included 22 patients with stenosis ≥ 70% in the carotid artery (11 symptomatic and 11 asymptomatic) who underwent carotid endarterectomy. The patients were divided into two groups: Control Group - hydrocortisone was not administered, and Group 1 - 500 mg intravenous hydrocortisone was administered during anesthetic induction. Plasma levels of MMP-8 and MMP-9 were measured preoperatively (24 hours before carotid endarterectomy) and at 1 hour, 6 hours and 24 hours after carotid endarterectomy. In carotid plaque, tissue levels of MMP-8 and MMP-9 were measured. Results Group 1 showed increased serum levels of MMP- 8 (994.28 pg/ml and 408.54 pg/ml, respectively; P=0.045) and MMP-9 (106,656.34 and 42,807.69 respectively; P=0.014) at 1 hour after carotid endarterectomy compared to the control group. Symptomatic patients in Group 1 exhibited lower tissue concentration of MMP-8 in comparison to the control group (143.89 pg/ml and 1317.36 respectively; P=0.003). There was a correlation between preoperative MMP-9 levels and tissue concentrations of MMP-8 (P=0.042) and MMP-9 (P=0.019) between symptomatic patients in the control group. Conclusion Hydrocortisone reduces the concentration of MMP- 8 in carotid plaque, especially in symptomatic patients. There was an association between systemic and tissue inflammation. PMID:26313719

[Why are carotid glomus tumours dangerous?].

PubMed

Certík, B; Třeška, V

2014-10-01

Carotid body tumours are rare, usually benign tumours. The dangerous nature of carotid body tumours is due to their hypervascularization and the intimate relationship to cervical arteries and cranial nerves. In a case report, the authors document that misdiagnosis and efforts to remove or obtain a biopsy of the tumour outside vascular centres can be more dangerous for the patient than the nature of the tumour itself.

Carotid Artery Screening

MedlinePlus

... the artery walls may signal the development of cardiovascular disease. top of page Who should consider carotid artery ... high blood pressure diabetes smoking high cholesterol known cardiovascular disease The American Heart Association guidelines also state that ...

Carotid Bulb Webs as a Cause of "Cryptogenic" Ischemic Stroke.

PubMed

Sajedi, P I; Gonzalez, J N; Cronin, C A; Kouo, T; Steven, A; Zhuo, J; Thompson, O; Castellani, R; Kittner, S J; Gandhi, D; Raghavan, P

2017-07-01

Carotid webs are intraluminal shelf-like filling defects at the carotid bulb with recently recognized implications in patients with recurrent ischemic stroke. We sought to determine whether carotid webs are an under-recognized cause of "cryptogenic" ischemic stroke and to estimate their prevalence in the general population. A retrospective review of neck CTA studies in young patients with cryptogenic stroke over the past 6 years ( n = 33) was performed to determine the prevalence of carotid webs compared with a control group of patients who received neck CTA studies for reasons other than ischemic stroke ( n = 63). The prevalence of carotid webs in the cryptogenic stroke population was 21.2% (95% CI, 8.9%-38.9%). Patients with symptomatic carotid webs had a mean age of 38.9 years (range, 30-48 years) and were mostly African American (86%) and women (86%). In contrast, only 1.6% (95% CI, 0%-8.5%) of patients in the control group demonstrated a web. Our findings demonstrate a statistically significant association between carotid webs and ischemic stroke (OR = 16.7; 95% CI, 2.78-320.3; P = .01). Carotid webs exhibit a strong association with ischemic stroke, and their presence should be suspected in patients lacking other risk factors, particularly African American women. © 2017 by American Journal of Neuroradiology.

Carotid artery stenting in patients with symptomatic carotid stenosis: a single-center series.

PubMed

Kessler, I; Gory, B; Macian, F; Nakiri, G; Al-Khawaldeh, M; Riva, R; Boncoeur, M P; Mounayer, C

2013-03-01

Carotid angioplasty with stenting (CAS) in patients with carotid stenosis (CS) has become more restricted in France especially since the disclosure of such studies as EVA-3S and Stent-supported percutaneous angioplasty of the carotid artery versus endarterectomy (SPACE). This report is of a series of CS cases contraindicated for endarterectomy that underwent CAS at a French center of interventional neuroradiology. Fifty-five patients with symptomatic CS more than 60% consecutively submitted to CAS between September 2008 and February 2011. The primary endpoint was either death or stroke within 30 days of the procedure; a secondary goal was to identify any possible factors that might have influenced the success and outcome of the intervention. The overall periprocedural stroke/death rate at 30 days was 5.4% (three out of 55 patients), with three non-disabling strokes and no deaths. Twenty-seven patients (49.1%) were treated with a cerebral protection device (CPD). Stent placement was achieved in all cases. Open- and closed-cell stents were implanted in 40 (72.7%) and 15 procedures (27.3%), respectively. Neither the use of a CPD, the carotid stent cell design nor any anatomical or technical factors were associated with a lower risk of stroke or death within 30 days of CAS. CAS in symptomatic patients with CS contraindicated for endarterectomy in this selected French series proved feasible and safe, with acceptable levels of morbidity. Use of a CPD, type of stent (open- or closed-cell), and anatomical and technical factors had no influence on the success of the procedure or the outcome within 30 days of the operation. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Contemporary medical therapies of atherosclerotic carotid artery disease.

PubMed

Cheng, Suk F; Brown, Martin M

2017-03-01

Contemporary medical therapy consists of identification and treatment of all patient-modifiable vascular risk factors. Specific atherosclerotic disease therapies are designed to reduce the risk of thrombosis, and the disease progression in order to reduce the risk of future cardiovascular events. Contemporary medical management emphasizes the need to support the patient in achieving lifestyle modifications and to adjust medication to achieve individualized target values for specific quantifiable risk factors. Antiplatelet therapy in the form of aspirin or clopidogrel is routinely used for the prevention of ischemic stroke in patients who have had a transient ischemic attack or stroke. There is evidence from a recent trial that the use of combination antiplatelet therapy with aspirin and clopidogrel started within 24 hours of minor stroke or transient ischemic attack reduces the risk of recurrent stroke compared to the use of aspirin alone, and therefore we use aspirin plus clopidogrel in recently symptomatic patients with carotid stenosis pending carotid revascularization. Anticoagulation with heparins or vitamin K antagonist is not recommended except in patients at risk for cardio-embolic events. Lowering blood pressure to target levels has been shown to slow down the progression of carotid artery stenosis and reduces the intima-media thickness of the carotid plaque, while lowering lipid levels with statins has become an essential element in the medical therapy of carotid artery stenosis. Diabetes management should be optimized. Lifestyle choices, including tobacco smoking, physical inactivity, unhealthy diet, obesity, and excessive alcohol intake, are all important modifiable vascular risk factors. The combination of dietary modification, physical exercise, and use of aspirin, a statin, and an antihypertensive agent can be expected to give a cumulative relative stroke risk reduction of 80%. The evidence suggests that intensive medical therapy is so effective that

Carotid artery bypass in acute postendarterectomy thrombosis.

PubMed

Paty, P S; Darling, R C; Cordero, J A; Shah, D M; Chang, B B; Leather, R P

1996-08-01

Carotid endarterectomy has demonstrated excellent results over the past 2 decades with combined stroke mortality of < 4% in most active centers. However, the optimal technique for surgical reconstruction for patients with acute postoperative deficits is more controversial. In the last 10 years (1985 to 1995), we performed 1,267 carotid endarterectomies, with 17 strokes (1.3%) and 16 deaths (1.2%). Twenty-four patients developed acute (within 72 hours) postoperative neurologic deficits. In 10 patients, the carotid artery was confirmed patent by duplex scan or angiography, and the neurologic deficit resolved without further therapy. Early reexploration was performed in 14 cases for suspected thrombosis associated with a new neurologic deficit. In each case, resection of the endarterectomy site and an interposition bypass was performed with greater saphenous vein (11), jugular vein (2), or polytetrafluoroethylene (2) grafts. (One patient required a new bypass for acute occlusion of the initial vein bypass.) Postoperatively, 8 patients had complete resolution of their deficit, 3 had minimal residual deficits, and 3 suffered permanent stroke. However, 2 of these patients died. Carotid artery bypass with exclusion of the endarterectomy site resulted in improvement in symptoms in 79% (11 of 14) of the patients and complete resolution in 57% (8 of 14). In long-term follow up (1 to 41 months), there have been no occlusions and one restenosis requiring revision at 11 months. Carotid artery bypass can be performed safely with acceptable results. The use of autogenous venous conduits allows reconstruction with an endothelial lined conduit that may improve results in patients with acute postoperative neurologic deficit secondary to thrombosis of the endarterectomized carotid artery.

An in vitro analysis of a carotid artery stent with a protective porous membrane.

PubMed

Müller-Hülsbeck, Stefan; Hüsler, Erhard J; Schaffner, Silvio R; Jahnke, Thomas; Glass, Christoph; Wenke, Rüdiger; Heller, Martin

2004-11-01

To prove the effectiveness of a new stent concept with integrated protection (MembraX [MX]) by comparing it with five cerebral protection devices designed for carotid angioplasty in an in vitro model. Two simulation series of embolization from carotid angioplasty have been performed. In the first series, polyvinyl-alcohol particles (150-250 microm [small], 355-500 microm [medium], 710-1000 microm [large]; 5 mg each) were injected into a silicone flow model simulating the aortic arch with a carotid bifurcation. The particles were injected proximally to the partially deployed MX stent or one of the following protection devices: Angioguard (AG), FilterWire EX (EX), Trap, Neuroshield (NS), or GuardWire Plus (GW). Particles evading the protection device were caught in a filter at the end of the flow model and weighed. In the second series, human plaque material (8-12 particles; total weight 6.09 +/- 0.01 mg; 500-1500 microm) was injected into the model with the respective devices. MX was compared with the AG, EX, Trap, and NS devices. MX had the most effective overall filtration performance for polyvinyl alcohol particles in the effluent of the internal carotid artery (ICA; 0.43 mg, 2.9%), compared with NS (0.53 mg, 3.5%), GW (1.10 mg, 7.0%), EX and AG (1.18 and 1.21 mg, respectively; 7.8% and 8.0%), and Trap (1.24 mg, 8.2%). MX performed best for the small particles (2.0% passed particles into ICA; P < .05 compared with all). Human plaque material was retained best in the in vitro model by MX (0.0%), followed by NS (0.8%), EX (1.3%), Trap (2.6%), and AG (4.4%). In vitro, none of the tested devices had the ability to prevent embolization completely. Comparing current designs, the MX device captured the highest percentage of the three different particle groups. Tested with human plaque emboli, MX performed effectively in filtering the particles in the ICA.

Carotid sinus syndrome as the presenting symptom of cystadenolymphoma.

PubMed

Noroozi, Nelson; Modabber, Ali; Hölzle, Frank; Braunschweig, Till; Riediger, Dieter; Gerressen, Marcus; Ghassemi, Alireza

2012-11-14

Carotid sinus syndrome is a serious manifestation of head and neck malignancy. The purpose of this study was to clarify the presence of carotid sinus syndrome in a patient with cystadenolymphoma. To our knowledge carotid sinus syndrome secondary to cystadenolymphoma has not been reported to date. A 45-year-old woman with one-week-old swelling in the left mandibular angle having disturbing symptoms of vertigo, consciousness and sinus arrest. Holter monitoring revealed several episodes of sinus arrest. Ultrasonography showed a well-defined space-occupying lesion of about 31 mm in length and 17 mm in width located in the deep lobe of the left parotid gland. Computerized tomography (CT) showed a large mass extending into the carotid space and protruding into the parapharyngeal space. Parotidectomy was performed. Surgical removal of the tumor resulted in complete amelioration of symptoms and disappearance of electrocardiogram abnormalities. Here we report on a clinical case of carotid sinus syndrome associated with cystadenolymphoma. To our knowledge carotid sinus syndrome secondary to cystadenolymphoma has not been reported to date, and is made more remarkable as a possible differential diagnosis after clarification of all possible causes. Early diagnosis and immediate management can minimize complications.

Uniaxial Tensile Properties of Atherosclerotic Carotid Artery After Mobilization of Pushing on Qiao-Gong: A Safety Study Using an Animal Model of Carotid Atherosclerosis.

PubMed

Qi, Ji; Zhang, Shaoqun; Zhang, Lei; Ping, Ruiyue; Ping, Kaike; Ye, Da; Shen, Honggui; Chen, Yili; Li, Yikai

2018-02-01

This study aimed to preliminarily explore the effects of the soft tissue mobilization of pushing on Qiao-Gong (MPQ) on biomechanical properties of the carotid artery using an animal model of carotid atherosclerosis (CAS). Fifty rabbits were randomly divided into 4 groups: animals with CAS treated with MPQ (CAS-MPQ [n = 15]); animals with CAS treated without MPQ (CAS [n = 15]); normal animals treated with MPQ (normal-MPQ [n = 10]); and a blank control group (n = 10). The MPQ procedure consisted of soft tissue mobilization of the Qiao-Gong acupoint on the front edge of the sternocleidomastoid muscle applied from top to bottom, by flat pushing with the thumb repeatedly for 20 times. Disease in the CAS models was induced by carotid artery balloon injury combined with a high-fat diet for 12 weeks. At the end of modeling, carotid color Doppler ultrasonography examination was performed to confirm which animal models were successfully induced with CAS, excluding model rabbits without typical CAS at the same time. Then, MPQ was applied on rabbits in the CAS-MPQ and the normal-MPQ groups for 3 weeks. By contrast, rabbits in the other 2 groups were fed normally without MPQ. Uniaxial failure tests were later performed on carotid arteries in all 4 groups, and at the end of the study, a 2-way factorial analysis of variance of the results was conducted. (1) At the end of modeling, 10 rabbits in the CAS-MPQ group and 9 in the CAS group were included with typical carotid atherosclerotic characteristics. (2) Young's elastic modulus of the rabbit carotid artery increased more significantly in the CAS-MPQ group than the CAS group. (3) Compared with normal rabbit carotid arteries, atherosclerotic carotid arteries had lower levels of ultimate stress and ultimate strain but higher levels of ultimate load. The uniaxial tensile mechanical properties of the rabbit atherosclerotic carotid artery were impaired after MPQ. Copyright © 2018. Published by Elsevier Inc.

The predictive value of retinal vascular findings for carotid artery atherosclerosis: are further recommendations with regard to carotid atherosclerosis screening needed?

PubMed

Song, Yeo-Jeong; Cho, Kyoung-Im; Kim, Seong-Man; Jang, Hyun-Duk; Park, Jung-Min; Kim, Sang-Soo; Kim, Dong-Jun; Lee, Hyeon-Gook; Kim, Tae-Ik

2013-05-01

Vascular retinopathy is the consequence of vascular disease, and the retina is the only place where the arteries can be visualized directly. The purpose of this study was to evaluate the predictive value of retinal vascular findings for carotid artery atherosclerosis. From December 2009 to January 2011, the carotid intima-media thickness (IMT) and total plaque area (TPA) were measured in 179 consecutive patients, who received a fundoscopic examination. The patients were divided into groups as follows: normal retinal artery (normal; n = 44), diabetic retinopathy (DR; n = 25), retinal artery occlusion (RAO; n = 17), retinal vein occlusion (RVO; n = 67), and hypertensive retinopathy (HTN-R; n = 26). The subjects were classified according to the presence of an increased (≥ 1 mm) IMT and plaque. The values of the mean carotid IMT in the patients with vascular retinopathy (DR, 0.87 ± 0.14 mm; RAO, 1.18 ± 0.47 mm; RVO, 0.84 ± 0.14 mm; HTN-R, 0.90 ± 0.20 mm) were significantly increased compared with those in the normal subjects (0.77 ± 0.13 mm). A total 77 of 135 vascular retinopathy patients demonstrated an increased IMT (57 %), and 97 vascular retinopathy patients had carotid artery plaque (72 %). The relative risk of vascular retinopathy in the prediction of an increased IMT and the presence of plaque was 2.79 and 3.95, respectively. Although The TPA was significantly increased in the patients with RAO (1.87 ± 2.67 cm(2)) and RVO (0.27 ± 0.23 cm(2)) compared with the normal subjects (0.18 ± 0.23 cm(2), all Ps < 0.05), there was no significant difference in the ipsilateral carotid IMT and TPA of the affected eye compared with that of the contralateral eye. In conclusion, vascular retinopathy demonstrated a good predictive value in identifying asymptomatic carotid artery atherosclerosis, and this was not confined to the ipsilateral carotid artery of the affected eye. Further recommendations with regard to carotid atherosclerosis screening in patients with

Evidence-Based Carotid Interventions for Stroke Prevention: State-of-the-art Review

PubMed Central

Morris, Dylan R.; Ayabe, Kengo; Inoue, Takashi; Sakai, Nobuyuki; Bulbulia, Richard; Halliday, Alison

2017-01-01

Carotid artery stenosis is responsible for between 10–20% of all ischaemic strokes. Interventions, such as carotid end-arterectomy and carotid stenting, effectively reduce the risk of stroke in selected individuals. This review describes the history of carotid interventions, and summarises reliable evidence on the safety and efficacy of these interventions gained from large randomised clinical trials. Early trials comparing carotid endarterectomy to medical therapy alone in symptomatic patients, and asymptomatic patients, demonstrated that endarterectomy halved the risk of stroke and perioperative death in these two unique populations. The absolute risk reduction was smaller in the asymptomatic carotid trials, consistent with their lower absolute stroke risk. More recent trials in symptomatic patients, suggest that carotid stenting has similar long term durability to carotid endarterectomy, but possibly has higher procedural hazards dominated by non-disabling strokes. The Asymptomatic Carotid Surgery Trial-2, along with individual patient data meta-analysis of all asymptomatic trials, will provide reliable evidence for the choice of intervention in asymptomatic patients in whom a decision has been made for carotid revascularisation. Given improvements in effective cardiovascular medical therapy, in particular lipid-lowering medications, there is renewed uncertainty as to whether carotid interventions still provide meaningful net reductions in stroke risk in asymptomatic populations. Four large trials in Europe and the US are currently underway, and are expected to report longterm results in the next decade. It is essential that surgeons, interventionalists, and physicians continue to randomise large numbers of patients from around the world to clarify current uncertainty around the management of asymptomatic carotid stenosis. PMID:28260723

Heparin surface stent-graft for the treatment of a carotid pseudoaneurysm.

PubMed

Tsolaki, Elpiniki; Elpiniki, Tsolaki; Salviato, Elisabetta; Rocca, Tiberio; Braccini, Lucia; Galeotti, Roberto; Mascoli, Francesco

2010-10-01

Carotid pseudoaneurysms are a rare consequence of carotid surgery, trauma, and infection. Historically, carotid aneurysms and pseudoaneurysms were treated surgically. However, endovascular techniques have recently become a valid alternative for the treatment of carotid pseudoaneurysms. The case of a 57-year-old male patient with a pseudoaneurysm of the right internal carotid artery is described. The patient came to our unit with a painless and pulsatile mass in the neck, which was growing slowly. Five years earlier, he had undergone surgery on a saccular aneurysm located on the distal extracranial segment of the right internal carotid artery. The pseudoaneurysm was successfully treated with a heparin surface Viabahn stent-graft system (Gore AL, Flagstaff, AZ). Heparin surface stent-grafts can be used for the treatment of carotid lesions and may offer protection against intimal hyperplasia and thrombosis. Further studies are needed to evaluate the long-term results. Copyright © 2010 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

A pilot study of the relationship between Doppler-estimated carotid and brachial artery flow and cardiac index.

PubMed

Weber, U; Glassford, N J; Eastwood, G M; Bellomo, R; Hilton, A K

2015-10-01

We measured carotid and brachial artery blood flow by Doppler ultrasound in 11 human volunteers, and related these to cardiac index and to each other. The median (IQR [range]) carotid arterial blood flow was 0.334 (0.223-0.381 [0.052-0.563]) l.min(-1) on the right and 0.315 (0.223-0.369 [0.061-0.690]) l.min(-1) on the left. The brachial arterial blood flow was 0.049 (0.033-0.062 [0.015-0.204]) l.min(-1) on the right and 0.039 (0.027-0.054 [0.011-0.116]) on the left. Cardiac index was 3.2 (2.8-3.5 [1.9-5.4]) l.min(-1) .m(-2) . There was a moderate to good correlation between right-and left-sided flows (brachial: ρ = 0.45; carotid: ρ = 0.567). Brachial and carotid flow had no or a negative correlation with cardiac index (right brachial: ρ = -0.145, left brachial: ρ = -0.349; right carotid: ρ = -0.376, left carotid: ρ = -0.285). In contrast to some previous studies, we found that Doppler-estimated peripheral arterial blood flows only show a weak correlation with cardiac index and cannot be used to provide non-invasive estimates of cardiac index in man. © 2015 The Association of Anaesthetists of Great Britain and Ireland.

The influence of constitutive law choice used to characterise atherosclerotic tissue material properties on computing stress values in human carotid plaques.

PubMed

Teng, Zhongzhao; Yuan, Jianmin; Feng, Jiaxuan; Zhang, Yongxue; Brown, Adam J; Wang, Shuo; Lu, Qingsheng; Gillard, Jonathan H

2015-11-05

Calculating high stress concentration within carotid atherosclerotic plaques has been shown to be complementary to anatomical features in assessing vulnerability. Reliability of stress calculation may depend on the constitutive laws/strain energy density functions (SEDFs) used to characterize tissue material properties. Different SEDFs, including neo-Hookean, one-/two-term Ogden, Yeoh, 5-parameter Mooney-Rivlin, Demiray and modified Mooney-Rivlin, have been used to describe atherosclerotic tissue behavior. However, the capacity of SEDFs to fit experimental data and the difference in the stress calculation remains unexplored. In this study, seven SEDFs were used to fit the stress-stretch data points of media, fibrous cap, lipid and intraplaque hemorrhage/thrombus obtained from 21 human carotid plaques. Semi-analytic solution, 2D structure-only and 3D fully coupled fluid-structure interaction (FSI) analyses were used to quantify stress using different SEDFs and the related material stability examined. Results show that, except for neo-Hookean, all other six SEDFs fitted the experimental points well, with vessel stress distribution in the circumferential and radial directions being similar. 2D structural-only analysis was successful for all seven SEDFs, but 3D FSI were only possible with neo-Hookean, Demiray and modified Mooney-Rivlin models. Stresses calculated using Demiray and modified Mooney-Rivlin models were nearly identical. Further analyses indicated that the energy contours of one-/two-term Ogden and 5-parameter Mooney-Rivlin models were not strictly convex and the material stability indictors under homogeneous deformations were not always positive. In conclusion, considering the capacity in characterizing material properties and stabilities, Demiray and modified Mooney-Rivlin SEDF appear practical choices for mechanical analyses to predict the critical mechanical conditions within carotid atherosclerotic plaques. Copyright © 2015 The Authors. Published by

Chronic Lowering of Blood Pressure by Carotid Baroreflex Activation: Mechanisms and Potential for Hypertension Therapy

PubMed Central

Lohmeier, Thomas E.; Iliescu, Radu

2011-01-01

Recent technical advances have renewed interest in device-based therapy for the treatment of drug-resistant hypertension. Findings from recent clinical trials regarding the efficacy of electrical stimulation of the carotid sinus for the treatment of resistant hypertension are reviewed here. The main goal of this article, however, is to summarize the preclinical studies that have provided insight into the mechanisms that account for the chronic blood pressure lowering effects of carotid baroreflex activation. Some of the mechanisms identified were predictable and confirmed by experimentation. Others have been surprising and controversial and resolution will require further investigation. Although feasibility studies have been promising, firm conclusions regarding the value of this device-based therapy for the treatment of resistant hypertension awaits the results of current multicenter trials. PMID:21357283

Normative values and correlates of carotid artery intima-media thickness and carotid atherosclerosis in Andean-Hispanics: The PREVENCION Study

PubMed Central

Pastorius, Catherine A.; Medina-Lezama, Josefina; Corrales-Medina, Fernando; Bernabé-Ortiz, Antonio; Paz-Manrique, Roberto; Salinas-Najarro, Belissa; Khan, Zubair A.; Takahashi, Junichiro; Toshima, Gen; Zea-Diaz, Humberto; Postigo-MacDowall, Mauricio; Chirinos-Pacheco, Julio; Ibañez, Francisco; Chirinos, Diana A.; Saif, Hassam; Chirinos, Julio A.

2010-01-01

Objectives Carotid intima-media thickness (cIMT) is an independent predictor of cardiovascular risk. Furthermore, ethnicity and gender-specific normative data are required to assess cIMT, which are not available for Andean-Hispanics. In addition, data regarding correlates of subclinical atherosclerosis in ethnic population are needed. Methods We studied 1448 adults enrolled in a population-based study in Peru. cIMT and carotid plaque were measured with high-resolution ultrasonography. A healthy reference sample (n=472) with no cardiovascular disease, normal weight and normal metabolic parameters was selected to establish normative cIMT values. Correlates of abnormal cIMT and carotid plaque were assessed in the entire population. Results In the reference sample, 95th-percentile cIMT values were both age and gender-dependent. In stepwise regression, selected predictors of increasing cIMT were: older age, impaired fasting glucose, diabetes mellitus, higher systolic blood pressure, higher LDL-cholesterol, smoking and male gender. Predictors of carotid plaque included older age, male gender, higher systolic blood pressure, lower diastolic blood pressure and higher LDL-cholesterol. HDL-cholesterol and C-reactive protein were not associated with cIMT or carotid plaque. The lack of association with HDL-cholesterol was confirmed using high performance liquid chromatography. Conclusions We present ethnic-specific cutoffs for abnormal cIMT applicable to Andean-Hispanics and correlates of subclinical atherosclerosis in this population. Pending longitudinal studies, our data supports several risk associations seen in other populations and can be used to identify Andean-Hispanics at increased risk for atherosclerotic cardiovascular disease. The lack of association between HDL-C and cIMT or carotid plaque in this population requires further investigation. PMID:20510418

Carotid artery disease

MedlinePlus

Here's what you can do to help prevent carotid artery disease and stroke: Quit smoking. Follow a healthy, low-fat diet. Do not drink more than 1 to 2 alcoholic drinks a day. Do not use recreational drugs. ...

Plaque components affect wall stress in stented human carotid artery: A numerical study

NASA Astrophysics Data System (ADS)

Fan, Zhen-Min; Liu, Xiao; Du, Cheng-Fei; Sun, An-Qiang; Zhang, Nan; Fan, Zhan-Ming; Fan, Yu-Bo; Deng, Xiao-Yan

2016-12-01

Carotid artery stenting presents challenges of in-stent restenosis and late thrombosis, which are caused primarily by alterations in the mechanical environment of the artery after stent implantation. The present study constructed patient-specific carotid arterial bifurcation models with lipid pools and calcified components based on magnetic resonance imaging. We numerically analyzed the effects of multicomponent plaques on the distributions of von Mises stresses (VMSs) in the patient-specific models after stenting. The results showed that when a stent was deployed, the large soft lipid pool in atherosclerotic plaques cushioned the host artery and reduced the stress within the arterial wall; however, this resulted in a sharp increase of VMS in the fibrous cap. When compared with the lipid pool, the presence of the calcified components led to slightly increased stresses on the luminal surface. However, when a calcification was located close to the luminal surface of the host artery and the stenosis, the local VMS was elevated. Overall, compared with calcified components, large lipid pools severely damaged the host artery after stenting. Furthermore, damage due to the calcified component may depend on location.

A novel treatment for embolising carotid dissection

PubMed Central

Jaipersad, A.S.; Tiivas, C.; Walton, G.; Imray, C.H.E.

2011-01-01

INTRODUCTION A rare but significant cause for stroke is sub-intimal carotid dissection and this mechanism accounts for approximately 2.5% of all strokes.1 Dissection of the carotid artery is often caused by trauma to the face or neck.2 Under 45 years old, it is the second leading cause of stroke.3 Neurological symptoms can be lacking or subtle, therefore the condition may be overlooked but the pathological processed is believed to be attributed to thromboembolism.4 Microemboli in the middle cerebral artery, are known as a risk factor for ischaemic stroke following a transient ischaemic attack (TIA) and can be detected by transcranial Doppler examination (TCD).5 The established treatment regime is antiplatelet therapy, anticoagulation or both along with supportive therapy.6 Current evidence suggests managing microemboli in both crescendo TIA's and post carotid endarterectomy improves outcome.7 We have found the use of Tirofiban, a potent intravenous antiplatelet agent currently licensed for use in acute coronary syndrome, effective in the treatment of microemboli in this manner.7 CASE PRESENTATION We report a case of symptomatic carotid artery dissection post radical neck dissection, causing TCD detected microemboli and successfully treated with Tirofiban. CONCLUSION We believe further study into the use of Tirofiban in the treatment of microemboli after carotid dissection is indicated. PMID:22288033

PLACD-7T Study: Atherosclerotic Carotid Plaque Components Correlated with Cerebral Damage at 7 Tesla Magnetic Resonance Imaging.

PubMed

den Hartog, A G; Bovens, S M; Koning, W; Hendrikse, J; Pasterkamp, G; Moll, F L; de Borst, G J

2011-02-01

In patients with carotid artery stenosis histological plaque composition is associated with plaque stability and with presenting symptomatology. Preferentially, plaque vulnerability should be taken into account in pre-operative work-up of patients with severe carotid artery stenosis. However, currently no appropriate and conclusive (non-) invasive technique to differentiate between the high and low risk carotid artery plaque in vivo is available. We propose that 7 Tesla human high resolution MRI scanning will visualize carotid plaque characteristics more precisely and will enable correlation of these specific components with cerebral damage. The aim of the PlaCD-7T study is 1: to correlate 7T imaging with carotid plaque histology (gold standard); and 2: to correlate plaque characteristics with cerebral damage ((clinically silent) cerebral (micro) infarcts or bleeds) on 7 Tesla high resolution (HR) MRI. We propose a single center prospective study for either symptomatic or asymptomatic patients with haemodynamic significant (70%) stenosis of at least one of the carotid arteries. The Athero-Express (AE) biobank histological analysis will be derived according to standard protocol. Patients included in the AE and our prospective study will undergo a pre-operative 7 Tesla HR-MRI scan of both the head and neck area. We hypothesize that the 7 Tesla MRI scanner will allow early identification of high risk carotid plaques being associated with micro infarcted cerebral areas, and will thus be able to identify patients with a high risk of periprocedural stroke, by identification of surrogate measures of increased cardiovascular risk.

PLACD-7T Study: Atherosclerotic Carotid Plaque Components Correlated with Cerebral Damage at 7 Tesla Magnetic Resonance Imaging

PubMed Central

den Hartog, A.G; Bovens, S.M; Koning, W; Hendrikse, J; Pasterkamp, G; Moll, F.L; de Borst, G.J

2011-01-01

Introduction: In patients with carotid artery stenosis histological plaque composition is associated with plaque stability and with presenting symptomatology. Preferentially, plaque vulnerability should be taken into account in pre-operative work-up of patients with severe carotid artery stenosis. However, currently no appropriate and conclusive (non-) invasive technique to differentiate between the high and low risk carotid artery plaque in vivo is available. We propose that 7 Tesla human high resolution MRI scanning will visualize carotid plaque characteristics more precisely and will enable correlation of these specific components with cerebral damage. Study objective: The aim of the PlaCD-7T study is 1: to correlate 7T imaging with carotid plaque histology (gold standard); and 2: to correlate plaque characteristics with cerebral damage ((clinically silent) cerebral (micro) infarcts or bleeds) on 7 Tesla high resolution (HR) MRI. Design: We propose a single center prospective study for either symptomatic or asymptomatic patients with haemodynamic significant (70%) stenosis of at least one of the carotid arteries. The Athero-Express (AE) biobank histological analysis will be derived according to standard protocol. Patients included in the AE and our prospective study will undergo a pre-operative 7 Tesla HR-MRI scan of both the head and neck area. Discussion: We hypothesize that the 7 Tesla MRI scanner will allow early identification of high risk carotid plaques being associated with micro infarcted cerebral areas, and will thus be able to identify patients with a high risk of periprocedural stroke, by identification of surrogate measures of increased cardiovascular risk. PMID:22294972

The Short-Term Effect of Ketogenic Diet on Carotid Intima-Media Thickness and Elastic Properties of the Carotid Artery and the Aorta in Epileptic Children.

PubMed

Doksöz, Önder; Güzel, Orkide; Yılmaz, Ünsal; İşgüder, Rana; Çeleğen, Kübra; Meşe, Timur; Uysal, Utku

2015-10-01

The aim of this prospective study is to investigate the effect of a 6-month-long ketogenic diet on carotid intima-media thickness, carotid artery, and aortic vascular functions. Thirty-eight drug-resistant epileptic patients who were being treated with ketogenic diet were enrolled. Fasting total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, total cholesterol, and glucose concentrations were measured and echocardiography was performed in all patients before the beginning of ketogenic diet and at the sixth month of treatment. The body weight, height, body mass index, serum levels of triglyceride, total cholesterol, and low-density lipoprotein increased significantly at month 6 when compared to baseline values (P < .05). Carotid intima-media thickness, elastic properties of the aorta, and carotid artery did not change at the sixth month of therapy compared to baseline values. A 6-month-long ketogenic diet has no effect on carotid intima-media thickness and elastic properties of the carotid artery and the aorta. © The Author(s) 2015.

Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body

PubMed Central

Kumar, Prem; Prabhakar, Nanduri R.

2014-01-01

The discovery of the sensory nature of the carotid body dates back to the beginning of the 20th century. Following these seminal discoveries, research into carotid body mechanisms moved forward progressively through the 20th century, with many descriptions of the ultrastructure of the organ and stimulus-response measurements at the level of the whole organ. The later part of 20th century witnessed the first descriptions of the cellular responses and electrophysiology of isolated and cultured type I and type II cells, and there now exist a number of testable hypotheses of chemotransduction. The goal of this article is to provide a comprehensive review of current concepts on sensory transduction and transmission of the hypoxic stimulus at the carotid body with an emphasis on integrating cellular mechanisms with the whole organ responses and highlighting the gaps or discrepancies in our knowledge. It is increasingly evident that in addition to hypoxia, the carotid body responds to a wide variety of blood-borne stimuli, including reduced glucose and immune-related cytokines and we therefore also consider the evidence for a polymodal function of the carotid body and its implications. It is clear that the sensory function of the carotid body exhibits considerable plasticity in response to the chronic perturbations in environmental O2 that is associated with many physiological and pathological conditions. The mechanisms and consequences of carotid body plasticity in health and disease are discussed in the final sections of this article. PMID:23728973

Ten-year risk of stroke in patients with previous cerebral infarction and the impact of carotid surgery in the Asymptomatic Carotid Surgery Trial.

PubMed

Streifler, Jonathan Y; den Hartog, Anne G; Pan, Samuel; Pan, Hongchao; Bulbulia, Richard; Thomas, Dafydd J; Brown, Martin M; Halliday, Alison

2016-12-01

Silent brain infarcts are common in patients at increased risk of stroke and are associated with a poor prognosis. In patients with asymptomatic carotid stenosis, similar adverse associations were claimed, but the impact of previous infarction or symptoms on the beneficial effects of carotid endarterectomy is not clear. Our aim was to evaluate the impact of prior cerebral infarction in patients enrolled in the Asymptomatic Carotid Surgery Trial, a large trial with 10-year follow-up in which participants whose carotid stenosis had not caused symptoms for at least six months were randomly allocated either immediate or deferred carotid endarterectomy. The first Asymptomatic Carotid Surgery Trial included 3120 patients. Of these, 2333 patients with baseline brain imaging were identified and divided into two groups irrespective of treatment assignment, 1331 with evidence of previous cerebral infarction, defined as a history of ischemic stroke or transient ischemic attack > 6 months prior to randomization or radiological evidence of an asymptomatic infarct (group 1) and 1002 with normal imaging and no prior stroke or transient ischemic attack (group 2). Stroke and vascular deaths were compared during follow-up, and the impact of carotid endarterectomy was observed in both groups. Baseline characteristics of patients with and without baseline brain imaging were broadly similar. Of those included in the present report, male gender and hypertension were more common in group 1, while mean ipsilateral stenosis was slightly greater in group 2. At 10 years follow-up, stroke was more common among participants with cerebral infarction before randomization (absolute risk increase 5.8% (1.8-9.8), p = 0.004), and the risk of stroke and vascular death was also higher in this group (absolute risk increase 6.9% (1.9-12.0), p = 0.007). On multivariate analysis, prior cerebral infarction was associated with a greater risk of stroke (hazard ratio = 1.51, 95% confidence

Stent recanalization of carotid tonsillar loop dissection using the Enterprise vascular reconstruction device.

PubMed

Rahal, Jason P; Gao, Bulang; Safain, Mina G; Malek, Adel M

2014-07-01

Although advances in endovascular techniques have permitted reconstruction of intimal dissections and related pseudoaneurysms of the extracranial cervical internal carotid artery, highly tortuous tonsillar loop anatomic variants still pose an obstacle to conventional extracranial self-expanding carotid stents. During a 12 year period, nine of 48 cases with cervical carotid dissections were associated with a tonsillar loop. Five patients required endovascular treatment, which was performed using a microcatheter-based technique with the low-profile Enterprise vascular reconstruction device (Codman Neurovascular, Raynham, MA, USA). Technical, radiographic, and clinical outcomes were analyzed for each patient. Dissection etiology was spontaneous in three patients, iatrogenic in one, and traumatic in one. Four near-occlusive tonsillar loop dissections were successfully recanalized during the acute phase. Dissection-related stenosis improved from 90±22% to 31±13%, with tandem stents needed in three instances to seal the inflow zone. There were no procedure-related transient ischemic attacks (TIA), minor/major strokes, or deaths. Angiographic follow-up for a mean of 28.0±21.6 months showed all stents were patent, with average stenosis of 25.2±12.2%. Focal ovalization and kinking of the closed-cell design was noted at the sharpest curve in one patient. Clinical outcome (follow-up of 28.1±21.5 months) demonstrated overall improvement with no clinical worsening, new TIA, or stroke. Tonsillar loop-associated carotid dissections can be successfully and durably recanalized using the low-profile Enterprise stent with an excellent long-term patency rate and low procedural risk. The possibility of stent kinking and low radial force should be considered when planning reconstruction with this device. Copyright © 2014 Elsevier Ltd. All rights reserved.

Patient-specific simulation in carotid artery stenting.

PubMed

Willaert, Willem; Aggarwal, Rajesh; Bicknell, Colin; Hamady, Mo; Darzi, Ara; Vermassen, Frank; Cheshire, Nicholas

2010-12-01

Patient-specific virtual reality (VR) simulation is a technologic advancement that allows planning and practice of the carotid artery stenting (CAS) procedure before it is performed on the patient. The initial findings are reported, using this novel VR technique as a tool to optimize technical and nontechnical aspects of this complex endovascular procedure. In the angiography suite, the same interventional team performed the VR rehearsal and the actual CAS on the patient. All proceedings were recorded to allow for video analysis of team, technical, and nontechnical skills. Analysis of both procedures showed identical use of endovascular tools, similar access strategy, and a high degree of similarity between the angiography images. The total procedure time (24.04 vs 60.44 minutes), fluoroscopy time (11.19 vs 21.04 minutes), and cannulation of the common carotid artery (1.35 vs 9.34) took considerably longer in reality. An extensive questionnaire revealed that all team members found that the rehearsal increased the subjective sense of teamwork (4/5), communication (4/5), and patient safety (4/5). A VR procedure rehearsal is a practical and feasible preparatory tool for CAS and shows a high correlation with the real procedure. It has the potential to enhance the technical, nontechnical, and team performance. Further research is needed to evaluate if this technology can lead to improved outcomes for patients. Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Validation of a basic neurosonology laboratory for detecting cervical carotid artery stenosis.

PubMed

de la Cruz Cosme, C; Dawid Milner, M S; Ojeda Burgos, G; Gallardo Tur, A; Márquez Martínez, M; Segura, T

2017-03-24

Most of the cases of ischaemic stroke in our setting are of atherothrombotic origin. Detecting intracranial and cervical carotid artery stenosis in patients with ischaemic stroke is therefore essential. Ultrasonography has become the tool of choice for diagnosing carotid artery stenosis because it is both readily accessibility and reliable. However, use of this technique must be validated in each laboratory. The purpose of this study is to validate Doppler ultrasound in our laboratory as a means of detecting severe carotid artery stenosis. We conducted an observational descriptive study to evaluate diagnostic tests. The results from transcranial and cervical carotid Doppler ultrasound scans conducted by neurologists were compared to those from carotid duplex scans performed by radiologists in patients diagnosed with stroke. Arteriography was considered the gold standard (MR angiography, CT angiography, or conventional arteriography). Our sample included 228 patients. Transcranial and cervical carotid Doppler ultrasound showed a sensitivity of 95% and specificity of 100% for detection of carotid artery stenosis > 70%, whereas carotid duplex displayed a sensitivity of 87% and a specificity of 94%. Transcranial carotid Doppler ultrasound achieved a sensitivity of 78% and a specificity of 98% for detection of intracranial stenosis. Doppler ultrasound in our neurosonology laboratory was found to be a useful diagnostic tool for detecting cervical carotid artery stenosis and demonstrated superiority to carotid duplex despite the lack of B-mode. Furthermore, this technique was found to be useful for detecting intracranial stenosis. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Influence of Preoperative Risk Factors on Outcome After Carotid Endarterectomy

PubMed Central

Sternbergh, W. Charles; Money, Samuel R.

2003-01-01

As supported by level 1 multicenter randomized trial data, carotid endarterectomy (CEA) has a very low risk of perioperative morbidity and excellent durability, and provides significant long-term reductions of the risk of stroke. At Ochsner, our 1.1% risk of major stroke or death after CEA (n=366) is a demonstration of the safety of this procedure in experienced hands. This treatment modality continues to be the gold standard for most patients with carotid artery occlusive disease. Almost half of these patients treated with CEA were considered “high-risk” as defined by ineligibility for past or present randomized carotid trials. Importantly, these “high-risk” patients had outcomes that were not statistically different from “low-risk” trial-eligible patients. Thus, evidence-based decision-making does not support the routine use of investigational carotid stenting in “high-risk” trial-ineligible patients. However, carotid stenting is clearly a valuable alternative for selected patients. Our challenge is to precisely define which patients will most benefit from medical, surgical, or catheter-based therapy for carotid artery occlusive disease. PMID:22470252

Clinical utility of carotid duplex ultrasound prior to cardiac surgery.

PubMed

Lin, Judith C; Kabbani, Loay S; Peterson, Edward L; Masabni, Khalil; Morgan, Jeffrey A; Brooks, Sara; Wertella, Kathleen P; Paone, Gaetano

2016-03-01

Clinical utility and cost-effectiveness of carotid duplex examination prior to cardiac surgery have been questioned by the multidisciplinary committee creating the 2012 Appropriate Use Criteria for Peripheral Vascular Laboratory Testing. We report the clinical outcomes and postoperative neurologic symptoms in patients who underwent carotid duplex ultrasound prior to open heart surgery at a tertiary institution. Using the combined databases from our clinical vascular laboratory and the Society of Thoracic Surgery, a retrospective analysis of all patients who underwent carotid duplex ultrasound within 13 months prior to open heart surgery from March 2005 to March 2013 was performed. The outcomes between those who underwent carotid duplex scanning (group A) and those who did not (group B) were compared. Among 3233 patients in the cohort who underwent cardiac surgery, 515 (15.9%) patients underwent a carotid duplex ultrasound preoperatively, and 2718 patients did not (84.1%). Among the patients who underwent carotid screening vs no screening, there was no statistically significant difference in the risk factors of cerebrovascular disease (10.9% vs 12.7%; P = .26), prior stroke (8.2% vs 7.2%; P = .41), and prior transient ischemic attack (2.9% vs 3.3%; P = .24). For those undergoing isolated coronary artery bypass grafting (CABG), 306 (17.8%) of 1723 patients underwent preoperative carotid duplex ultrasound. Among patients who had carotid screening prior to CABG, the incidence of carotid disease was low: 249 (81.4%) had minimal or mild stenosis (<50%); 25 (8.2%) had unilateral moderate stenosis (50%-69%); 10 (3.3%) had bilateral moderate stenosis; 9 (2.9%) had unilateral severe stenosis (70%-99%); 5 (1.6%) had contralateral moderate stenosis; 2 (0.7%) had bilateral severe stenosis; 4 (1.3%) had unilateral occluded with contralateral less than 50% stenosis, 1 (0.3%) had unilateral occluded with contralateral (70%-99%) stenosis; and 1 had bilateral occluded carotid

Carotid artery protrusion and dehiscence in patients with acromegaly.

PubMed

Sasagawa, Yasuo; Tachibana, Osamu; Doai, Mariko; Hayashi, Yasuhiko; Tonami, Hisao; Iizuka, Hideaki; Nakada, Mitsutoshi

2016-10-01

Acromegaly is a systemic disease which causes multiple bony alterations. Some authors reported that acromegalic patients have risk factors for an intraoperative vascular injury due to the specific anatomical features of their sphenoid sinus. The objective of our study was to analyze the anatomic characteristics of sphenoid sinus in acromegalic patients compared with controls, by evaluation of computed tomography (CT) findings. We examined 45 acromegalic (acromegaly group) and 45 non-acromegalic patients (control group) with pituitary adenomas who were matched for sex, age, height, tumor size, and cavernous sinus invasion (Knosp grade). Preoperative CT of the pituitary region including the sphenoid sinus was used to evaluate the following anatomic characteristics: type of sphenoid sinus (sellar or pre-sellar/conchal); intrasphenoid septa (non/single or multiple); carotid artery protrusion; carotid artery dehiscence; intercarotid distance. Sixteen acromegalic patients (35.5 %) and 6 controls (13.3 %) had carotid artery protrusion. Additionally, 10 acromegalic patients (22.2 %) and 3 controls (6.6 %) had carotid artery dehiscence. Carotid artery protrusion and dehiscence were more frequent in the acromegaly group than in control group (p = 0.013 and 0.035, respectively). Other anatomic characteristics (type of sphenoid sinus, intrasphenoid septa, and intracarotid distance) showed no significant differences between acromegaly and control groups. Our study suggests that carotid artery protrusion and dehiscence occur more frequently among acromegalic patients, compared with non-acromegalic patients. It is important for surgeons to be aware of these anatomic variations to avoid vital complications, such as carotid injuries, during surgery.

Carotid artery intimal medial thickness and carotid artery plaques in hypertensive patients with non-arteritic anterior ischaemic optic neuropathy.

PubMed

Zhu, Wenhui; Chen, Tingting; Jin, Ling; Wang, Haoyu; Yao, Fengjuan; Wang, Congyao; Wang, Qi; Congdon, Nathan

2017-10-01

To assess the correlation of carotid artery intimal medial thickness (C-IMT) and carotid artery plaque score (CPS) of the common carotid artery with non-arteritic anterior ischemic optic neuropathy (NAION) in hypertensive patients. This case-control study recruited 192 subjects. Forty-eight patients had NAION with systemic hypertension, 46 had hypertension without visual complaints, and 98 were normal controls. C-IMT and common carotid arterial plaque were measured by high-resolution vascular ultrasonography. High-density lipoprotein (HDL) in patients with NAION (1.24 ± 0.31) was significantly lower than that of the Hypertensive group (1.39 ± 0.30, P = 0.034). The C-IMT in the affected side of patients with NAION (1.00 ± 0.23) was significantly increased compared to the unaffected side (0.83 ± 0.19, P < 0.001), the Hypertensive group (0.83 ± 0.17, P < 0.001), and the Normal group (0.69 ± 0.16, P < 0.001). The presence of carotid artery plaque was more frequent in the patients with NAION, compared to either the Hypertensive group (P = 0.001) or the Normal group (P < 0.001). By multiple regression analysis, lower high-density lipoprotein (HDL) (P = 0.009), thicker C-IMT (P = 0.002), CPS Grade = 1 (P = 0.028), and Grade = 2 (P = 0.005) were associated with increased NAION risk, when the NAION group compared with the Hypertensive group (OR > 1.0). Systolic blood pressure (P = 0.001), thicker C-IMT (P < 0.001), CPS Grade = 1 (P = 0.006), Grade = 2 (P = 0.002), and Grade = 3 (P = 0.015) were associated with increased NAION risk, when the NAION group compared with the Normal group (OR > 1.0). C-IMT and CPS were associated with NAION in hypertensive patients, suggesting that NAION might be associated with carotid artery atherosclerosis. This association may be due to similar pathological changes of the inner vascular walls in the carotid artery and the arteries supplying the optic nerve head.

[An integrated segmentation method for 3D ultrasound carotid artery].

PubMed

Yang, Xin; Wu, Huihui; Liu, Yang; Xu, Hongwei; Liang, Huageng; Cai, Wenjuan; Fang, Mengjie; Wang, Yujie

2013-07-01

An integrated segmentation method for 3D ultrasound carotid artery was proposed. 3D ultrasound image was sliced into transverse, coronal and sagittal 2D images on the carotid bifurcation point. Then, the three images were processed respectively, and the carotid artery contours and thickness were obtained finally. This paper tries to overcome the disadvantages of current computer aided diagnosis method, such as high computational complexity, easily introduced subjective errors et al. The proposed method could get the carotid artery overall information rapidly, accurately and completely. It could be transplanted into clinical usage for atherosclerosis diagnosis and prevention.

Real-Time Elastography Visualization and Histopathological Characterization of Rabbit Atherosclerotic Carotid Arteries.

PubMed

Wang, ZhenZhen; Liu, NaNa; Zhang, LiFeng; Li, XiaoYing; Han, XueSong; Peng, YanQing; Dang, MeiZheng; Sun, LiTao; Tian, JiaWei

2016-01-01

To evaluate the feasibility of non-invasive vascular real-time elastography imaging (RTE) in visualizing the composition of rabbit carotid atherosclerotic plaque as determined by histopathology, a rabbit model of accelerated carotid atherosclerosis was used. Thirty rabbits were randomly divided into two groups of 15 rabbits each. The first group was fed a cholesterol-rich diet and received balloon-induced injury the left common carotid artery endothelium, whereas the second group only received a cholesterol-rich diet. The rabbits were all examined in vivo with HITACHI non-invasive vascular real-time elastography (Hi-RTE) at baseline and 12 wk, and results from the elastography were compared with American Heart Association histologic classifications. Hi-RTE and the American Heart Association histologic classifications had good agreement, with weighted Cohen's kappa (95% confidence internal) of 0.785 (0.649-0.920). Strains of segmented plaques that were stained in different colors were statistically different (p < 0.0001). The sensitivity and specificity of elastograms for detecting a lipid core were 95.5% and 61.5%, respectively, and the area under the receiver operating characteristic curve was 0.789, with a 95% confidence interval of 0.679 to 0.876. This study is the first to indicate the feasibility of utilizing Hi-RTE in visualizing normal and atherosclerotic rabbit carotid arteries non-invasively. This affordable and reliable method can be widely applied in research of both animal and human peripheral artery atherosclerosis. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Extramedullary plasmacytoma in the carotid space: Expanding the differential diagnosis.

PubMed

Deshpande, Sneha Satish; Kane, Shubhada; Arya, Supreeta

2014-10-01

Plasma cell neoplasms have been classified into various types, with a range of clinical and radiological presentations. Extramedullary plasmacytoma (EMP) is a subset of plasma cell neoplasms which presents as an isolated non-osseous soft tissue mass. Though carotid space neoplasms are commonly encountered, EMP in the carotid space is rare and seldom considered in the initial differential diagnosis of a carotid space mass. These tumors can be treated by surgery or radiotherapy. On the other hand, the commonly encountered tumors in the carotid space are treated surgically. Also, it is mandatory to exclude multiple myeloma in the patients presenting with EMP. Hence, accurate and early diagnosis has therapeutic and prognostic implications. We report a rare case of EMP of the carotid space, describing the imaging features and the differential diagnoses with clues pointing to this rare entity.

The Surgical Challenge of Carotid Artery and Fallopian Canal Dehiscence in Chronic Ear Disease: A Pitfall for Endoscopic Approach

PubMed Central

Pauna, Henrique F.; Monsanto, Rafael C.; Schachern, Patricia A.; Costa, Sady S.; Kwon, Geeyoun; Paparella, Michael M.; Cureoglu, Sebahattin

2016-01-01

Objective Endoscopic procedures are becoming common in middle ear surgery. Inflammation due to chronic ear disease can cause bony erosion of the carotid artery and Fallopian canals, making them more vulnerable during surgery. The objective of this study was to determine whether or not chronic ear disease increases dehiscence of the carotid artery and Fallopian canals. Design Comparative human temporal bone study. Setting Otopathology laboratory. Participants We selected 78 temporal bones from 55 deceased donors with chronic otitis media or cholesteatoma, and then compared those 2 groups with a control group of 27 temporal bones from 19 deceased donors with no middle ear disease. Main outcome measures We analyzed the middle ear, carotid artery canal, and Fallopian canal, looking for signs of dehiscence of its bony coverage, using light microscopy. Results We found an increased incidence in dehiscence of the carotid artery and Fallopian canals in temporal bones with chronic middle ear disease. The size of the carotid artery canal dehiscence was larger in the middle ear diseased groups, and its bony coverage, when present, was also thinner compared to the control group. Dehiscence of the carotid artery canal was more frequently located closer to the promontory. The incidence of Fallopian canal dehiscence was significantly higher in temporal bones from donors older than 18 years with chronic middle ear disease. Conclusion The increased incidence of the carotid artery and Fallopian canal dehiscence in temporal bones with chronic middle ear disease elevates the risk of adverse events during middle ear surgery. Level of Evidence N/A. PMID:27455393

Short-Term Results of Carotid Endarterectomy and Stenting After the Introduction of Carotid Magnetic Resonance Imaging: A Single-Institution Retrospective Study.

PubMed

Fukumitsu, Ryu; Yoshida, Kazumichi; Kurosaki, Yoshitaka; Torihashi, Koichi; Sadamasa, Nobutake; Koyanagi, Masaomi; Narumi, Osamu; Sato, Tsukasa; Chin, Masaki; Handa, Akira; Yamagata, Sen; Miyamoto, Susumu

2017-05-01

Although carotid artery stenting (CAS) has been gaining popularity as an alternative to carotid endarterectomy (CEA), perioperative stroke rate following contemporary CAS remains significantly higher than stroke rate after CEA. The purpose of this study was to assess perioperative (within 30 days) therapeutic results in patients with carotid stenosis (CS) after introduction of preoperative carotid magnetic resonance imaging plaque evaluation in a single center performing both CEA and CAS. Based on prospectively collected data for patients with CS who were scheduled for carotid revascularization, retrospective analysis was conducted of 295 consecutive patients with CS. An intervention was selected after consideration of periprocedural risks for both CEA and CAS. Concerning risk factors for CAS, results of magnetic resonance imaging plaque evaluation were emphasized with a view toward reducing embolic complications. CAS was performed in 114 patients, and CEA was performed in 181 patients. Comparing baseline characteristics of the 295 patients, age, T1 signal intensity of plaque, symptomatic CS, urgent intervention, and diabetes mellitus differed significantly between CAS and CEA groups. Among patients who underwent CAS, new hyperintense lesions on diffusion-weighted imaging were confirmed in 47 patients. New hyperintense lesions on diffusion-weighted imaging were recognized in 21.4% of patients who underwent CEA (n = 39), significantly less frequent than in patients who underwent CAS. The overall short-term outcome of CEA and CAS is acceptable. Preoperative carotid magnetic resonance imaging evaluation of plaque might contribute to low rates of ischemic complications in CAS. Copyright © 2017 Elsevier Inc. All rights reserved.

Subclinical Carotid Atherosclerosis in Asymptomatic Subjects With Type 2 Diabetes Mellitus.

PubMed

Rubinat, Esther; Marsal, Josep Ramon; Vidal, Teresa; Cebrian, Cristina; Falguera, Mireia; Vilanova, Ma Belen; Betriu, Àngels; Fernández, Elvira; Franch, Josep; Mauricio, Dídac

2016-01-01

Subjects with type 2 diabetes mellitus are considered to be at high risk for cardiovascular disease. The identification of carotid atherosclerosis is a validated surrogate marker of cardiovascular disease. Nurses are key professionals in the improvement and intensification of cardiovascular preventive strategies. The aim is to study the presence of carotid atherosclerosis in a group of asymptomatic subjects with type 2 diabetes mellitus and no previous clinical cardiovascular disease. A total of 187 patients with type 2 diabetes mellitus and 187 age- and sex-matched subjects without type 2 diabetes mellitus were studied in this cross-sectional, observational, cohort study. Standard operational procedures were applied by the nursing team regarding physical examination and carotid ultrasound assessment. Common, bulb, and internal carotid arteries were explored by measuring intima-media thickness and identifying atherosclerotic plaques. Carotid intima-media thickness (c-IMT) and carotid plaque prevalence were significantly greater in diabetic subjects than in the control group. Carotid plaques and c-IMT were more frequent in men than in women and increased with increasing age. In the multivariate analysis, age, gender, waist circumference, systolic blood pressure, and hypercholesterolemia were positively associated with c-IMT, whereas age, gender, and weight were positively associated with carotid plaque. The current nurse-led study shows that subjects with type 2 diabetes mellitus have a high prevalence of subclinical atherosclerosis that is associated with cardiovascular risk factors.

Contrast-enhanced ultrasound imaging of intraplaque neovascularization and its correlation to plaque echogenicity in human carotid arteries atherosclerosis.

PubMed

Cattaneo, Mattia; Staub, Daniel; Porretta, Alessandra P; Gallino, Jeanne Marie; Santini, Paolo; Limoni, Costanzo; Wyttenbach, Rolf; Gallino, Augusto

2016-11-15

Currently the most widely accepted predictor of stroke risk in patients with carotid atherosclerosis is the degree of stenoses. Plaque echogenicity on ultrasound imaging (US) and intraplaque neovascularization (IPNV) are becoming recognized as factors of plaque vulnerability. Aim of the study was to investigate the correlation between the echogenicity of the carotid atherosclerosis by standard US and the degree of IPNV by contrast enhanced US (CEUS). We recruited 45 consecutive subjects with an asymptomatic ≥50% carotid artery stenoses. Carotid plaque echogenicity at standard US was visually graded according to Gray-Weale classification (GW) and measured by the grayscale median (GSM), a semi-automated measurement performed by Adobe Photoshop©. On CEUS imaging IPNV was graded by different point scales according to the visual appearance of contrast within the plaque as follows: CEUS_A (1=absent; 2=present); CEUS_B (increasing IPNV from 1 to 3); and CEUS_C (increasing IPNV from 0 to 3). The correlation between echogenicity by GW and IPNV grading was as follows: CEUS_B (-0.130 p .423), CEUS_C (-0.108, p .509), CEUS_A (0.021, p .897). The correlation between echogenicity by GSM measurement and IPNV was as follows: using a CEUS_A (-0.125, p .444), CEUS_C (-0.021, p .897) (0.005, p .977). No correlation was found statistically significant. Our results display that there is no significant correlation between plaque echogenicity and IPNV. The small sample number and the multifaceted pathophysiology of the atherosclerotic plaque may explain the absence of statistically significantly correlation. Curtailing vulnerability explanation to either IPNV or echolucency may be misleading. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Carotid-vertebrobasilar Anastomoses with Reference to Their Segmental Property.

PubMed

Namba, Katsunari

2017-06-15

The primitive carotid-vertebrobasilar anastomoses are primitive embryonic cerebral vessels that temporarily provide arterial supply from the internal carotid artery to the longitudinal neural artery, the future vertebrobasilar artery in the hindbrain. Four types known are the trigeminal, otic, hypoglossal, and proatlantal intersegmental arteries. The arteries are accompanied by their corresponding nerves and resemble an intersegmental pattern. These vessels exist in the very early period of cerebral arterial development and rapidly involute within a week. Occasionally, persistence of the carotid to vertebrobasilar anastomosis is discovered in the adult period, and is considered as the vestige of the corresponding primitive embryonic vessel. The embryonic development and the segmental property of the primitive carotid-vertebrobasilar anastomoses are discussed. This is followed by a brief description of the persisting anastomoses in adults.

Carotid artery stenting in the SPACE and EVA-3S trials: analysis and update.

PubMed

Mansour, M Ashraf

2008-03-01

Carotid artery stenting is an alternative to carotid endarterectomy. Although the stroke and mortality rates after stenting are low, it is yet to be proved that stenting is superior or equal to endarterectomy in low-risk symptomatic and asymptomatic patients. A summary of the results of 2 recent trials comparing carotid stenting with carotid endarterectomy, SPACE, and EVA-3S, is presented herein. Both trials failed to prove noninferiority of carotid stenting compared with carotid endarterectomy.

Age-Specific Sex Differences in Magnetic Resonance Imaging-Depicted Carotid Intraplaque Hemorrhage.

PubMed

Singh, Navneet; Moody, Alan R; Zhang, Bowen; Kaminski, Isabella; Kapur, Kush; Chiu, Stephanie; Tyrrell, Pascal N

2017-08-01

Stroke rates are higher in men compared with women in the fourth through seventh decades of life, and higher rates may result from differences in carotid intraplaque hemorrhage (IPH), an unstable atherosclerotic plaque component. We report age-specific sex differences in the presence of magnetic resonance imaging-depicted carotid IPH. Patients (n=1115) underwent magnetic resonance imaging for carotid IPH between 2005 and 2014. Low-grade carotid stenosis patients (n=906) without prior endarterectomy were eligible for this cross-sectional study. Of the 906 patients included (mean age±SD in years, 66.98±15.15), 63 (6.95%) had carotid IPH. In men and women, carotid IPH was present in 11.43% (48 of 420) and 3.09% (15 of 486), respectively ( P <0.0001). Multivariable logistic regression analysis confirmed greater odds of carotid IPH in men for all ages: 45 to 54 (odds ratio=45.45; 95% confidence interval, 3.43-500), 55 to 64 years (odds ratio=21.74; 95% confidence interval, 3.21-142.86), 65 to 74 years (odds ratio=10.42; 95% confidence interval, 2.91-37.04), and ≥75 years (odds ratio=5.00; 95% confidence interval, 2.31-10.75). Male sex modified the effect of age on the presence of carotid IPH (β=0.074; SE=0.036; P =0.0411). Men have greater age-specific odds of magnetic resonance imaging-depicted carotid IPH compared with women. With increasing age post-menopause, the odds of carotid IPH in women becomes closer to that of men. Delayed onset of carotid IPH in women, an unstable plaque component, may partly explain differential stroke rates between sexes, and further studies are warranted. © 2017 American Heart Association, Inc.

Improvement in Cerebral and Ocular Hemodynamics Early after Carotid Endarterectomy in Patients of Severe Carotid Artery Stenosis with or without Contralateral Carotid Occlusion.

PubMed

Wang, Jian; Wang, Weici; Jin, Bi; Zhang, Yanrong; Xu, Ping; Xiang, Feixiang; Zheng, Yi; Chen, Juan; Sheng, Shi; Ouyang, Chenxi; Li, Yiqing

2016-01-01

Purpose. To investigate the alternation in cerebral and ocular blood flow velocity (BFV) in patients of carotid stenosis (CS) with or without contralateral carotid occlusion (CO) early after carotid endarterectomy (CEA). Patients and Methods. Nineteen patients underwent CEA for ≥50% CS. Fourteen patients had the unilateral CS, and five patients had the ipsilateral CS and the contralateral CO. Transcranial Doppler (TCD) and Color Doppler Imaging (CDI) were performed before and early after CEA. Results. In patients with unilateral CS, significant improvements in BFV were observed in anterior cerebral artery (ACA) and middle cerebral artery (MCA) on the ipsilateral side after CEA. In patients of ipsilateral CS and contralateral CO, significant improvements in BFV were observed in the ACA and MCA not only on the ipsilateral side but also on the contralateral side postoperatively. The ipsilateral ophthalmic artery (OA) retrograde flows in two patients were recovered to anterograde direction following CEA. The BFV in short posterior ciliary artery (SPCA) of the ipsilateral side significantly increased postoperatively irrespective of the presence of contralateral CO. Conclusions. CEA improved cerebral anterior circulation hemodynamics especially in patients of unilateral CS and contralateral CO, normalized the OA reverse flow, and increased the blood perfusion of SPCA.

Multidisciplinary approach to carotid stenting.

PubMed

Mak, C S; Chambers, B R; Clark, D J; Molan, M; Brooks, M; Roberts, N; Fell, G; Roberts, A K; New, G; Donnan, G A

2011-11-01

Stroke neurologists, vascular surgeons, interventional neuroradiologists and interventional cardiologists have embraced carotid angioplasty and stenting (CAS) because of potential advantages over carotid endarterectomy (CEA). At Austin Health, a multidisciplinary neuro-interventional group was formed to standardise indications and facilitate training. The aims of this study were to describe our organisational model and to determine whether 30-day complications and early outcomes were similar to those of major trials. A clinical protocol was developed to ensure optimal management. CAS was performed on patients with high medical risk for CEA, with technically difficult anatomy for CEA, or who were randomised to CAS in a trial. From October 2003 to May 2008, 47 patients (34 male, mean age 71.5) underwent CAS of 50 carotid arteries. Forty-three cases had ipsilateral carotid territory symptoms within the previous 12 months. The main indications for CAS were high risk for CEA (n= 17) and randomised to CAS (n= 21). Interventionists were proctored in 27 cases. The procedural success rate was 94% with two cases abandoned because of anatomical problems and one because of on-table angina. Hypotension requiring vasopressor therapy occurred in 12 cases (24%). The duration of follow up was one to 44 months (mean 6.8 months). The 30-day rate of peri-procedural stroke or death was 6% and the one-year rate of peri-procedural stroke or death or subsequent ipsilateral stroke was 10.6%. Restenosis occurred in 13% (all asymptomatic). A multidisciplinary approach is a useful strategy for initiating and sustaining a CAS programme. © 2011 The Authors. Internal Medicine Journal © 2011 Royal Australasian College of Physicians.

Carotid DSA based CFD simulation in assessing the patient with asymptomatic carotid stenosis: a preliminary study.

PubMed

Zhang, Dong; Xu, Pengcheng; Qiao, Hongyu; Liu, Xin; Luo, Liangping; Huang, Wenhua; Zhang, Heye; Shi, Changzheng

2018-03-12

Cerebrovascular events are frequently associated with hemodynamic disturbance caused by internal carotid artery (ICA) stenosis. It is challenging to determine the ischemia-related carotid stenosis during the intervention only using digital subtracted angiography (DSA). Inspired by the performance of well-established FFRct technique in hemodynamic assessment of significant coronary stenosis, we introduced a pressure-based carotid arterial functional assessment (CAFA) index generated from computational fluid dynamic (CFD) simulation in DSA data, and investigated its feasibility in the assessment of hemodynamic disturbance preliminarily using pressure-wired measurement and arterial spin labeling (ASL) MRI as references. The cerebral multi-delay multi-parametric ASL-MRI and carotid DSA including trans-stenotic pressure-wired measurement were implemented on a 65-year-old man with asymptomatic unilateral (left) ICA stenosis. A CFD simulation using simplified boundary condition was performed in DSA data to calculate the CAFA index. The cerebral blood flow (CBF) and arterial transit time (ATT) of ICA territories were acquired. CFD simulation showed good correlation (r = 0.839, P = 0.001) with slight systematic overestimation (mean difference - 0.007, standard deviation 0.017) compared with pressure-wired measurement. No significant difference was observed between them (P = 0.09). Though the narrowing degree of in the involved ICA was about 70%, the simulated and measured CAFA (0.942/0.937) revealed a functionally nonsignificant stenosis which was also verified by a compensatory final CBF (fronto-temporal/fronto-parietal region: 51.58/45.62 ml/100 g/min) and slightly prolonged ATT (1.23/1.4 s) in the involved territories, together with a normal left-right percentage difference (2.1-8.85%). The DSA based CFD simulation showed good consistence with invasive approach and could be used as a cost-saving and efficient way to study the relationship between

Does human cognition allow Human Factors (HF) certification of advanced aircrew systems?

NASA Technical Reports Server (NTRS)

Macleod, Iain S.; Taylor, Robert M.

1994-01-01

This paper has examined the requirements of HF specification and certification within advanced or complex aircrew systems. It suggests reasons for current inadequacies in the use of HF in the design process, giving some examples in support, and suggesting an avenue towards the improvement of the HF certification process. The importance of human cognition to the operation and performance of advanced aircrew systems has been stressed. Many of the shortfalls of advanced aircrew systems must be attributed to over automated designs that show little consideration on either the mental limits or the cognitive capabilities of the human system component. Traditional approaches to system design and HF certification are set within an over physicalistic foundation. Also, traditionally it was assumed that physicalistic system functions could be attributed to either the human or the machine on a one to one basis. Moreover, any problems associated with the parallel needs, or promoting human understanding alongside system operation and direction, were generally equated in reality by the natural flexibility and adaptability of human skills. The consideration of the human component of a complex system is seen as being primarily based on manifestations of human behavior to the almost total exclusion of any appreciation of unobservable human mental and cognitive processes. The argument of this paper is that the considered functionality of any complex human-machine system must contain functions that are purely human and purely cognitive. Human-machine system reliability ultimately depends on human reliability and dependability and, therefore, on the form and frequency of cognitive processes that have to be conducted to support system performance. The greater the demand placed by an advanced aircraft system on the human component's basic knowledge processes or cognition, rather than on skill, the more insiduous the effects the human may have on that system. This paper discusses one

Carotid Artery Disease

MedlinePlus

... brain (cerebrovascular disease). Like the heart, the brain’s cells need a constant supply of oxygen-rich blood. This blood supply is delivered to the brain by the 2 large carotid arteries in the front of your neck and by 2 smaller vertebral arteries at the back of your ...

AHA classification of coronary and carotid atherosclerotic plaques by grating-based phase-contrast computed tomography.

PubMed

Hetterich, Holger; Webber, Nicole; Willner, Marian; Herzen, Julia; Birnbacher, Lorenz; Hipp, Alexander; Marschner, Mathias; Auweter, Sigrid D; Habbel, Christopher; Schüller, Ulrich; Bamberg, Fabian; Ertl-Wagner, Birgit; Pfeiffer, Franz; Saam, Tobias

2016-09-01

To evaluate the potential of grating-based phase-contrast computed-tomography (gb-PCCT) to classify human carotid and coronary atherosclerotic plaques according to modified American Heart Association (AHA) criteria. Experiments were carried out at a laboratory-based set-up consisting of X-ray tube (40 kVp), grating-interferometer and detector. Eighteen human carotid and coronary artery specimens were examined. Histopathology served as the standard of reference. Vessel cross-sections were classified as AHA lesion type I/II, III, IV/V, VI, VII or VIII plaques by two independent reviewers blinded to histopathology. Conservative measurements of diagnostic accuracies for the detection and differentiation of plaque types were evaluated. A total of 127 corresponding gb-PCCT/histopathology sections were analyzed. Based on histopathology, lesion type I/II was present in 12 (9.5 %), III in 18 (14.2 %), IV/V in 38 (29.9 %), VI in 16 (12.6 %), VII in 34 (26.8 %) and VIII in 9 (7.0 %) cross-sections. Sensitivity, specificity and positive and negative predictive value were ≥0.88 for most analyzed plaque types with a good level of agreement (Cohen's kappa = 0.90). Overall, results were better in carotid (kappa = 0.97) than in coronary arteries (kappa = 0.85). Inter-observer agreement was high with kappa = 0.85, p < 0.0001. These results indicate that gb-PCCT can reliably classify atherosclerotic plaques according to modified AHA criteria with excellent agreement to histopathology. • Different atherosclerotic plaque types display distinct morphological features in phase-contrast CT. • Phase-contrast CT can detect and differentiate AHA plaque types. • Calcifications caused streak artefacts and reduced sensitivity in type VI lesions. • Overall agreement was higher in carotid than in coronary arteries.

The risk of carotid artery stenting compared with carotid endarterectomy is greatest in patients treated within 7 days of symptoms.

PubMed

Rantner, Barbara; Goebel, Georg; Bonati, Leo H; Ringleb, Peter A; Mas, Jean-Louis; Fraedrich, Gustav

2013-03-01

Among patients with symptomatic carotid artery stenosis, carotid artery stenting (CAS) is associated with a higher risk of periprocedural stroke or death than carotid endarterectomy (CEA). Uncertainty remains whether the balance of risk changes with time since the most recent ischemic event. We investigated the association of time between the qualifying ischemic event and treatment (0-7 days, 8-14 days, and >14 days) with the risk of stroke or death within 30 days after CAS or CEA in a pooled analysis of data from individual patients randomized in the Endarterectomy vs Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial, the Stent-Protected Angioplasty versus Carotid Endarterectomy (SPACE) trial, and the International Carotid Stenting Study (ICSS). Data were analyzed with a fixed-effect binomial regression model adjusted for source trial. Information on time of qualifying event was available for 2839 patients. In the first 30 days after intervention, any stroke or death occurred significantly more often in the CAS group (110/1434 [7.7%]) compared with the CEA group (54/1405 [3.8%]; crude risk ratio, 2.0; 95% confidence interval, 1.5-2.7). Patients undergoing CEA within the first 7 days of the qualifying event had the lowest periprocedural stroke or death rate (3/106 [2.8%]). Patients treated with CAS in the same period had a 9.4% risk of periprocedural stroke or death (13/138; risk ratio CAS vs CEA: 3.4; 95% confidence interval, 1.01-11.8; adjusted for age, sex, and type of qualifying event). Patients treated between 8 and 14 days showed a periprocedural stroke or death rate of 3.4% (7/208) and 8.1% (19/234), respectively, for CEA and CAS. The latest treatment group had 4% complications in the CEA group (44/1091) and 7.3% in the CAS group (78/1062). The increase in risk of CAS compared with CEA appears to be greatest in patients treated within 7 days of symptoms. Early surgery might remain most effective in stroke prevention in patients

On recent advances in human engineering.

PubMed

Anton, Roman

2016-01-01

Advances in embryology, genetics, and regenerative medicine regularly attract attention from scientists, scholars, journalists, and policymakers, yet implications of these advances may be broader than commonly supposed. Laboratories culturing human embryos, editing human genes, and creating human-animal chimeras have been working along lines that are now becoming intertwined. Embryogenic methods are weaving traditional in vivo and in vitro distinctions into a new "in vivitro" (in life in glass) fabric. These and other methods known to be in use or thought to be in development promise soon to bring society to startling choices and discomfiting predicaments, all in a global effort to supply reliably rejuvenating stem cells, to grow immunologically nonprovocative replacement organs, and to prevent, treat, cure, or even someday eradicate diseases having genetic or epigenetic mechanisms. With humanity's human-engineering era now begun, procedural prohibitions, funding restrictions, institutional controls, and transparency rules are proving ineffective, and business incentives are migrating into the most basic life-sciences inquiries, wherein lie huge biomedical potentials and bioethical risks. Rights, health, and heritage are coming into play with bioethical presumptions and formal protections urgently needing reassessment.

Carotid artery phantom designment and simulation using field II

NASA Astrophysics Data System (ADS)

Lin, Yuan; Yang, Xin; Ding, Mingyue

2013-10-01

Carotid atherosclerosis is the major cause of ischemic stroke, a leading cause of mortality and disability. Morphology and structure features of carotid plaques are the keys to identify plaques and monitoring the disease. Manually segmentation on the ultrasonic images to get the best-fitted actual size of the carotid plaques based on physicians personal experience, namely "gold standard", is a important step in the study of plaque size. However, it is difficult to qualitatively measure the segmentation error caused by the operator's subjective factors. In order to reduce the subjective factors, and the uncertainty factors of quantification, the experiments in this paper were carried out. In this study, we firstly designed a carotid artery phantom, and then use three different beam-forming algorithms of medical ultrasound to simulate the phantom. Finally obtained plaques areas were analyzed through manual segmentation on simulation images. We could (1) directly evaluate the different beam-forming algorithms for the ultrasound imaging simulation on the effect of carotid artery; (2) also analyze the sensitivity of detection on different size of plaques; (3) indirectly reflect the accuracy of the manual segmentation base on segmentation results the evaluation.

Carotid-Femoral Pulse Wave Velocity: Impact of Different Arterial Path Length Measurements

PubMed Central

Sugawara, Jun; Hayashi, Koichiro; Yokoi, Takashi; Tanaka, Hirofumi

2009-01-01

Background Carotid-femoral pulse wave velocity (PWV) is the most established index of arterial stiffness. Yet there is no consensus on the methodology in regard to the arterial path length measurements conducted on the body surface. Currently, it is not known to what extent the differences in the arterial path length measurements affect absolute PWV values. Methods Two hundred fifty apparently healthy adults (127 men and 123 women, 19-79 years) were studied. Carotid-femoral PWV was calculated using (1) the straight distance between carotid and femoral sites (PWVcar–fem), (2) the straight distance between suprasternal notch and femoral site minus carotid arterial length (PWV(ssn–fem)-(ssn–car)), (3) the straight distance between carotid and femoral sites minus carotid arterial length (PWV(car–fem)-(ssn–car)), and (4) the combined distance from carotid site to the umbilicus and from the umbilicus to femoral site minus carotid arterial length (PWV(ssn–umb–fem)-(ssn–car)). Results All the calculated PWV were significantly correlated with each other (r=0.966-0.995). PWV accounting for carotid arterial length were 16-31% lower than PWVcar–fem. PWVcar–fem value of 12 m/sec corresponded to 8.3 m/sec for PWV(ssn–fem)-(ssn–car), 10.0 m/sec for PWV(car–fem)-(ssn–car), and 8.9 m/sec for PWV(ssn–umb–fem)-(ssn–car). Conclusion Different body surface measurements used to estimate arterial path length would produce substantial variations in absolute PWV values. PMID:20396400

Carotid duplex ultrasound and transcranial Doppler findings in commercial divers and pilots.

PubMed

Dormanesh, Banafshe; Vosoughi, Kia; Akhoundi, Fahimeh H; Mehrpour, Masoud; Fereshtehnejad, Seyed-Mohammad; Esmaeili, Setareh; Sabet, Azin Shafiee

2016-12-01

The risky working environments of divers and pilots, and the possible role of extreme ambient pressure in carotid stenosis, make ischemic stroke an important occupational concern among these professionals. In this study, we aimed to evaluate the association of being exposed to hyperbaric or hypobaric conditions with carotid artery stenosis by comparing common carotid intima-media thickness (CCIMT) and blood flow velocities of cerebral arteries in divers and pilots using carotid duplex ultrasound (CDUS) and transcranial Doppler (TCD). CDUS and transtemporal TCD were performed in 29 divers, 36 pilots and 30 control participants. Medical history, blood pressure, lipid profile and blood sugar were recorded to control the previously well-known risk factors of atherosclerosis. Findings of the CDUS and TCD [including: CCIMT and blood flow velocities of internal carotid artery (ICA), common carotid artery (CCA), and middle cerebral artery (MCA)] of divers and pilots were compared with those of the control group using regression analysis models. Both right and left side CCIMT were significantly higher in divers (P < 0.05) and pilots (P < 0.05) in comparison with the control group. Carotid index [peak systolic velocity (PSV) of ICA/PSV of CCA) of divers and pilots were also higher than the control group. TCD findings were not significantly different between divers, pilots, and the control group. Increased CCIMT and carotid index in diver and pilot groups appear to be suggestive of accelerated atherosclerosis of carotid artery in these occupational groups.

Carotid body tumor imitator: An interesting case of Castleman's disease.

PubMed

Shakir, Hakeem J; Diletti, Sara M; Hart, Alexandra M; Meyers, Joshua E; Dumont, Travis M; Siddiqui, Adnan H

2015-01-01

There are very few reports in the literature of Castleman's disease affecting the carotid artery and a single previous report of a case of Castleman's disease of the neck originally mistaken as a carotid body tumor. We describe a rare case of Castleman's disease, manifesting with classic radiographic hallmarks of a carotid body tumor. The postoperative pathologic examination identified the resected mass as Castleman's lymphadenopathy. The management of this particular case is discussed, and the findings are highlighted. We present a unique case of a tumor initially and incorrectly diagnosed as a carotid body tumor. However, after comprehensive treatment with endovascular and surgical modalities and subsequent pathologic examination, the diagnosis of this rare entity was made.

Multicenter experience on eversion versus conventional carotid endarterectomy in symptomatic carotid artery stenosis: observations from the Stent-Protected Angioplasty Versus Carotid Endarterectomy (SPACE-1) trial.

PubMed

Demirel, Serdar; Attigah, Nicolas; Bruijnen, Hans; Ringleb, Peter; Eckstein, Hans-Henning; Fraedrich, Gustav; Böckler, Dittmar

2012-07-01

Carotid endarterectomy (CEA) is beneficial in patients with symptomatic carotid artery stenosis. However, randomized trials have not provided evidence concerning the optimal CEA technique, conventional or eversion. The outcome of 563 patients within the surgical randomization arm of the Stent-Protected Angioplasty versus Carotid Endarterectomy in Symptomatic Patients (SPACE-1) trial was analyzed by surgical technique subgroups: eversion endarterectomy versus conventional endarterectomy with patch angioplasty. The primary end point was ipsilateral stroke or death within 30 days after surgery. Secondary outcome events included perioperative adverse events and the 2-year risk of restenosis, stroke, and death. Both groups were similar in terms of demographic and other baseline clinical variables. Shunt frequency was higher in the conventional CEA group (65% versus 17%; P<0.0001). The risk of ipsilateral stroke or death within 30 days after surgery was significantly greater with eversion CEA (9% versus 3%; P=0.005). There were no statistically significant differences in the rate of perioperative secondary outcome events with the exception of a significantly higher risk of intraoperative ipsilateral stroke rate in the eversion CEA group (4% versus 0.3%; P=0.0035). The 2-year risk of ipsilateral stroke occurring after 30 days was significantly higher in the conventional CEA group (2.9% versus 0%; P=0.017). In patients with symptomatic carotid artery stenosis, conventional CEA appears to be associated with better periprocedural neurological outcome than eversion CEA. Eversion CEA, however, may be more effective for long-term prevention of ipsilateral stroke. These findings should be interpreted with caution noting the limitations of the post hoc, nonrandomized nature of the analysis.

Retained Subintimal Pellet in a Carotid Artery

PubMed Central

Manousi, Maria; Sarantitis, Ioannis; Diamantopoulos, Athanasios; Kakkos, Stavros K.; Lampropoulos, George; Tsolakis, Ioannis A.

2011-01-01

A shotgun pellet is depicted in the present image in a carotid artery under the intima, which remained intact without local complications for up to six months. There is lack of data regarding the natural history of such a carotid pellet, but the experience from the myocardium is that, in the absence of infection, completely embedded missiles are usually asymptomatic, tolerated well and may be left in place. PMID:21860728

The critical role of the external carotid artery in cerebral perfusion of patients with total occlusion of the internal carotid artery.

PubMed

Dalainas, I; Avgerinos, E D; Daskalopoulos, M E; Papapetrou, A; Papasideris, C P; Katsikas, V; Xiromeritis, K; Moulakakis, K; Gianakopoulos, T; Liapis, C D

2012-02-01

The ipsilateral external carotid artery (ECA) can potentially provide an important collateral pathway for cerebral blood flow in the presence of occlusion or severe stenosis of the internal carotid artery (ICA), recovering up to 15% of the middle cerebral arterial flow. The aim of the study is to elucidate the role of ECA in cerebral flow of patients with total ICA occlusion. Retrospective study of prospectively collected data of 139 patients with total ICA occlusions. The patients were divided to symptomatic and asymptomatic and were categorized in four subgroups according to the stenosis rates: A) ipsilateral ECA<70% and contralateral internal carotid artery stenosis <70%; B) ipsilateral ECA stenosis <70% and contralateral internal carotid artery stenosis ≥70%; C) ipsilateral ECA stenosis ≥70% and contralateral ICA stenosis <70%; D) ipsilateral ECA stenosis ≥70% and contralateral ICA stenosis ≥75%. Fifty eight (41.7%) patients were asymptomatic. The highest rate (48.2%) of asymptomatic patients was in Group A. Among patients with strokes, the highest rate belonged in groups C and D (44.4% and 50% respectively) where ipsilateral ECA stenosis was ≥70% irrespectively of the contralateral ICA patency. Ipsilateral external carotid artery stenosis ≥70% proved to be and independent risk factor for symptom presentation (P=0.013). The study reveals the significant role of ECA patency in cerebral flow in patients with ICA occlusion.

Old and New Techniques as a Safe Hybrid Approach for Carotid Tandem Lesions.

PubMed

Barillà, David; Massara, Mafalda; Alberti, Antonino; Volpe, Alberto; Cutrupi, Andrea; Versace, Paolo; Volpe, Pietro

2016-04-01

Carotid revascularization is performed to prevent stroke. Carotid tandem lesions represent a challenge for treatment, and a hybrid approach may result effective. A high-risk 65-year-old woman presented with a "tandem lesion" of left common and internal carotid artery. She was deemed unfit for "simple" standard carotid endarterectomy (CEA). A "single-step" safe hybrid procedure was scheduled for the patient. A "Cormier" carotid vein graft bypass with a retrograde stenting was performed under local anesthesia. The "safe hybrid procedure" for tandem lesions of the common and internal carotid artery is effective and suitable in high-risk patients in a high-volume centers. Copyright © 2016 Elsevier Inc. All rights reserved.

Peptidases of the peripheral chemoreceptors: biochemical, immunological, in vitro hydrolytic studies and electron microscopic analysis of neutral endopeptidase-like activity of the carotid body.

PubMed

Kumar, G K

1997-02-14

The purposes of the present study are to identify and characterize the major peptidase(s) that may be involved in the inactivation of neuropeptides in the mammalian carotid body. Measurements of a number of peptidase activities in the cell-free extract of the cat carotid body using specific substrates and inhibitors indicated that the previously identified neutral endopeptidase (NEP)-like activity [Kumar et al., Brain Res., 517 (1990) 341-343] is the major peptidase in the chemoreceptor tissue. The NEP-like activity of the carotid body was further characterized using a monoclonal antibody to human neutral endopeptidase, EC 3.4.24.11. Immune blot analysis indicated strong immunoreactivity toward the cat and calf carotid bodies but a weak cross-reactivity with the rabbit carotid body. Furthermore, western blot analysis of the cat carotid body extract revealed the presence of a major 97-kDa protein and a minor 200-kDa protein. The 97-kDa NEP form of the carotid body was comparable to EC 3.4.24.11 and was consistent with its reported molecular weight suggesting NEP-like activity of the carotid body is structurally similar to the neutral endopeptidase, EC 3.4.24.11. In order to assess whether NEP is the primary peptide degrading activity in the cat carotid body in vitro hydrolysis studies using substance P (SP) as a model peptide were performed. HPLC analysis showed that SP is hydrolyzed maximally at pH 7.0 by carotid body peptidases with the formation of SP(1-7) and SP(1-8) as stable intermediates. Inhibitors specific to NEP also inhibited the SP-hydrolyzing activity of the carotid body. Analyses of the cell-free extracts showed the occurrence of both NEP and SP-hydrolyzing activities in the rabbit and rat carotid bodies although at 2- and 4-fold lower levels respectively than that observed in the cat carotid body. Immunoelectron microscopy showed that NEP-specific immunoreactivity is associated with the intercellular region between the type I cells and cell clusters

Prevalence of calcified carotid artery on panoramic radiographs in postmenopausal women.

PubMed

Taheri, Jamileh Beigom; Moshfeghi, Mahkameh

2009-01-01

This study was designed to evaluate the prevalence of calcified carotid artery in 50 year-old and older postmenopausal dental outpatients for early diagnosis of individuals at risk of stroke. This is a descriptive study of 200 panoramic radiographs. These radiographs included post-menopausal women referring to the Department of Oral Medicine at Shahid Beheshti Faculty of Dentistry during 2006-2007. The x-ray machine, developer and film type were the same for all the radiographs. Statistical analysis included chi-square test and Fisher's exact test. We found 22 calcified carotid arteries. The left and right carotid arteries were involved in 7 and 9 cases, respec-tively. In 6 cases both carotid arteries were calcified. Four individuals had no vascular risk factor excluding age and others had at least one risk factor. We found significant statistical correlation between hypertension, past history of myocardial infarction, and hypercholesterolemia with calcified carotid artery on panoramic radiographs. Under the limitations of the present study, prevalence of calcified carotid arteries is 11.0 % in 50 year-old and older postmenopausal dental outpatients.

[Research progress of needles with knife-edge for carotid cardiac syndrome].

PubMed

Tan, Lingqiong; Zhao, Yanling

2015-04-01

According to topographic anatomy, pathogenesis and by retrieving, summarizing and analyzing literature regarding needle-knife and needles with knife-edge for carotid cardiac syndrome, it is found out that clinical misdiagnosis rate of carotid cardiac syndrome is considerably high. Needle-knife and needles with knife-edge could significantly improve the clinical symptoms of carotid cardiac syndrome, showing characteristic and advantage in treatment, but it is deficient in technique standard and efficacy criteria that should be united and authoritative. Researches regarding pathogenesis of carotid cardiac syndrome are not systematic. Clinical observation regarding long-term efficacy and relapse of needle-knife and needles with knife-edge treatment is rare. It is believed that the awareness on carotid cardiac syndrome should be increased to reduce misdiagnosis; scientific and standardized technique standard and efficacy criteria should be established; systematic and comprehensive researches regarding mechanism of needle-knife and needles with knife-edge for carotid cardiac syndrome should be launched; besides, clinical discussion regarding its long-term efficacy should start to provide a better clinical guideline.

Analysis of carotid lumen surface morphology using three-dimensional ultrasound imaging

NASA Astrophysics Data System (ADS)

Chiu, Bernard; Beletsky, Vadim; Spence, J. David; Parraga, Grace; Fenster, Aaron

2009-03-01

Carotid plaque surface irregularity and ulcerations play an important role in the risk of ischemic stroke. Ulcerated or fissured plaque, characterized by irregular surface morphology, exposes thrombogenic materials to the bloodstream, possibly leading to life- or brain-threatening thrombosis and embolization. Therefore, the quantification of plaque surface irregularity is important to identify high-risk plaques that would likely lead to vascular events. Although a number of studies have characterized plaque surface irregularity using subjective classification schemes with two or more categories, only a few have quantified surface irregularity using an objective and continuous quantity, such as Gaussian or mean curvature. In this work, our goal was to use both Gaussian and mean curvatures for identifying ulcers from 3D carotid ultrasound (US) images of human subjects. Before performing experiments using patient data, we verified the numerical accuracy of the surface curvature computation method using discrete spheres and tori with different sampling intervals. We also showed that three ulcers of the vascular phantom with 2 mm, 3 mm and 4 mm diameters were associated with high Gaussian and mean curvatures, and thus, were easily detected. Finally, we demonstrated the application of the proposed method for detecting ulcers on luminal surfaces, which were segmented from the 3D US images acquired for two human subjects.

Management of carotid Dacron patch infection: a case report using median sternotomy for proximal common carotid artery control and in situ polytetrafluoroethylene grafting.

PubMed

Illuminati, Giulio; Calio', Francesco G; D'Urso, Antonio; Ceccanei, Gianluca; Pacilè, Maria Antonietta

2009-01-01

We report on a 58-year-old male who presented with an enlarging cervical hematoma 3 months following carotid endarterectomy with Dacron patch repair, due to septic disruption of the Dacron patch secondary to presumed infection. The essential features of this case are the control of the proximal common carotid artery gained through a median sternotomy, because the patient was markedly obese with minimal thyromental distance, and the treatment consisting of in situ polytetrafluoroethylene bypass grafting, due to the absence of a suitable autogenous saphenous vein. Median sternotomy is rarely required in case of reintervention for septic false aneurysms and hematomas following carotid endarterectomy but should be considered whenever difficult control of the common carotid artery, when entering the previous cervicotomy, is anticipated. In situ polytetrafluoroethylene grafting can be considered if autogenous vein material is lacking.

Carotid Artery Stenting, Endarterectomy, or Medical Treatment Alone: The Debate Is Not Over

PubMed Central

Kassaian, Seyed Ebrahim; Goodarzynejad, Hamidreza

2011-01-01

The management of carotid artery stenosis reduces the risk of stroke and its related deaths. Management options include risk factor modification and medical therapy, carotid endarterectomy (CEA), and carotid artery stenting (CAS). Although several randomized controlled trials (RCTs), mostly conducted in late-1980s and mid-1990s, have proved CEA to be effective in the prevention of ipsilateral ischemic events in selected patients with carotid artery stenosis, aggressive risk factor modification and medical therapy with recently introduced antiplatelet agents, statins, and more effective antihypertensive medications may have reduced compelling indications for immediate surgery in asymptomatic populations. Also recently, due to improvements in percutaneous techniques and carotid stents, CAS has received wide attention as a potential alternative to CEA. Herein, we review the recent data on the management options of carotid artery stenosis and seek to identify the most appropriate treatment strategy in selected patients with carotid artery stenosis. PMID:23074598

Effect of Cervical Siphon of External and Internal Carotid Arteries.

PubMed

Singh, Rajani; Tubbs, Richard Shane

2017-10-01

Variant courses, configuration, and branching pattern of the external and internal carotid arteries, especially when curved in S-shape, are important for hemodynamic changes and clinical implications. Therefore, the aim of the study is to report abnormal cervical siphons observed in external and internal carotid arteries to explore clinical significance by review of literature and hemodynamic changes theoretically.The right common carotid artery bifurcated into external and internal carotid arteries at the level of the upper border of thyroid cartilage in a 70-year-old female cadaver. After bifurcation, the external carotid artery underwent severe tortuosity coursing through 5 bends at points A, B, C, D, and E from its origin to termination and 2 bends at A' and B' in internal carotid artery in the cervical region. The angles between inflow and out flow of the blood at the bends were measured and the change in velocity at each bend was computed for both arteries. Hemodynamic changes were calculated, compared and relevant clinical complications were theoretically correlated.The angles of 20°, 30°, 51°, 52°, 60°, and 28°, 48° were formed by 5 bends of external and 2 bends of internal carotid arteries, respectively. The curved courses of these arteries caused reduction in velocity/stasis, turbulence, and low shear stress. Such kinks might cause stroke, ischemia and mistaken for tumors and abscess in imagery leading to or otherwise producing iatrogenic repercussions. This study will be useful for anatomists, clinicians, and radiologists.

Markerless attenuation correction for carotid MRI surface receiver coils in combined PET/MR imaging

NASA Astrophysics Data System (ADS)

Eldib, Mootaz; Bini, Jason; Robson, Philip M.; Calcagno, Claudia; Faul, David D.; Tsoumpas, Charalampos; Fayad, Zahi A.

2015-06-01

The purpose of the study was to evaluate the effect of attenuation of MR coils on quantitative carotid PET/MR exams. Additionally, an automated attenuation correction method for flexible carotid MR coils was developed and evaluated. The attenuation of the carotid coil was measured by imaging a uniform water phantom injected with 37 MBq of 18F-FDG in a combined PET/MR scanner for 24 min with and without the coil. In the same session, an ultra-short echo time (UTE) image of the coil on top of the phantom was acquired. Using a combination of rigid and non-rigid registration, a CT-based attenuation map was registered to the UTE image of the coil for attenuation and scatter correction. After phantom validation, the effect of the carotid coil attenuation and the attenuation correction method were evaluated in five subjects. Phantom studies indicated that the overall loss of PET counts due to the coil was 6.3% with local region-of-interest (ROI) errors reaching up to 18.8%. Our registration method to correct for attenuation from the coil decreased the global error and local error (ROI) to 0.8% and 3.8%, respectively. The proposed registration method accurately captured the location and shape of the coil with a maximum spatial error of 2.6 mm. Quantitative analysis in human studies correlated with the phantom findings, but was dependent on the size of the ROI used in the analysis. MR coils result in significant error in PET quantification and thus attenuation correction is needed. The proposed strategy provides an operator-free method for attenuation and scatter correction for a flexible MRI carotid surface coil for routine clinical use.

A Prospective, Multicenter Study of a Novel Mesh-Covered Carotid Stent: The CGuard CARENET Trial (Carotid Embolic Protection Using MicroNet).

PubMed

Schofer, Joachim; Musiałek, Piotr; Bijuklic, Klaudija; Kolvenbach, Ralf; Trystula, Mariusz; Siudak, Zbigniew; Sievert, Horst

2015-08-17

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. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Technological advances for studying human behavior

NASA Technical Reports Server (NTRS)

Roske-Hofstrand, Renate J.

1990-01-01

Technological advances for studying human behavior are noted in viewgraph form. It is asserted that performance-aiding systems are proliferating without a fundamental understanding of how they would interact with the humans who must control them. Two views of automation research, the hardware view and the human-centered view, are listed. Other viewgraphs give information on vital elements for human-centered research, a continuum of the research process, available technologies, new technologies for persistent problems, a sample research infrastructure, the need for metrics, and examples of data-link technology.

Evidence overview: benefit of cerebral protection devices during carotid artery stenting.

PubMed

Vos, Jan A

2017-04-01

Embolic protection devices (EPDs) are often used during carotid angioplasty and stenting (CAS) to reduce procedural cerebral emboli. This manuscript seeks to present an overview of evidence on EPDs during CAS. There are three categories of EPDs: distal occlusion (DO-EPD), filter (F-EPD) and proximal occlusion (PO-EPD). DO and F-EPDs have the disadvantage that the device has to be advanced through the stenosis, without protection and that the device may damage the distal internal carotid artery (ICA). F-EPDs have the advantage of maintaining antegrade flow throughout the procedure. PO-EPDs occlude the ICA and external carotid artery (ECA) (blocking antegrade flow), but do not require manipulation of the stenosis before protection is established. All devices add to procedural time and costs. Many single-center series and meta-analyses have shown lower incidence of procedural complications and surrogate endpoints when EPDs are used. However, these series are hampered by a serious confounder: protected cases were generally performed later, when institutions had more experience and when newer stents, techniques etc. had become available. Two small randomized trials showed no difference between filter-protected and unprotected procedures in clinical outcome, but found significantly more surrogate endpoints (diffusion-weighted MRI lesions and transcranial Doppler detected micro-emboli) in the protected groups. Comparing between groups of EPDs, some studies slightly favored PO to F-EPDs, while others found no difference. All devices were associated with low numbers of clinical cerebral complications, but frequent surrogate signs of cerebral embolization. In conclusion, all currently available EPDs still result in some degree of cerebral embolization. No solid recommendation for a particular type of EPDs, if any, can be derived from literature.

Carotid baroreflex response following 30 days exposure to simulated microgravity

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Doerr, D. F.; Eckberg, D. L.; Fritsch, J. M.; Vernikos-Danellis, J.

1989-01-01

The mechanism of the carotid-baroreflex response to weightlessness was investigated in human subjects exposed to simulated microgravity (30 days of 6-day head-down bed rest followed by 5 days of recovery). Baroreceptor-cardiac reflex responses were elicited by a complex sequence of pressure changes delivered to a neck chamber device. The shape of the sigmoid baroreceptor-cardiac response curve was examined for alterations and the occurrence of resetting, as well as for a possible association of the impaired baroreflex function with hypotension during the postexposure orthostatic stress. It was found that the exposure to head-down bed rest caused a significant shift on the R-R interval axis, which paralleled reductions and elevations in baseline HR such that the baseline R-R (operational point) remained in the same position on the response curve. This shift in the location of the reflex relation indicates a significant resetting of the carotid baroreceptors, which may represent an appropriate adaptation which contributes to the maintenance of a constant resting arterial blood pressure before, during, and after bed rest, observed in these study.

Rationale and design of a multidisciplinary national real-world registry on carotid stenting: the Italian Registry for Carotid Stenting (RISC).

PubMed

Biasi, Giorgio M; Deleo, Gaetano; Froio, Alberto; Cremonesi, Alberto; Inglese, Luigi; Lavitrano, Marialuisa; Setacci, Carlo

2006-04-01

The Registro Italiano per lo Stenting Carotideo (RISC, Italian Registry for Carotid Stenting) has been organized by Italian specialists from different disciplines directly involved in the prevention of stroke due to carotid plaques through stenting of carotid lesions. The Registry has been endorsed by the national societies of 4 different specialties: vascular surgery, interventional cardiology, radiology, and neuroradiology. Each society contributed in the planning stage. The basis for the registry is to collect data on carotid stenting procedures performed by different specialists with different techniques in a "real-world" setting without the limitations of a randomized clinical trial. The Registry was funded to enroll at least 1200 patients over a minimum period of 36 months. The results will be analyzed using the intention-to-treat principle and are anticipated in late 2006. Primary endpoints of the registry are the 30-day combined death and stroke rate and the occurrence of restenosis and ipsilateral neurological deficit at 12 and 24 months. Considerable attention has been paid to the registry's quality control program to ensure scientific validation. An online database facilitates the collection of data with speed and accuracy.

Carotid Stenting for Restenosis after Endarterectomy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Counsell, Andrew, E-mail: mzysapc@doctors.org.uk; Ghosh, Jonathan, E-mail: jonathanghosh@mac.com; McCollum, Charles C. N., E-mail: charles.mccollum@manchester.ac.uk

2011-06-15

Introduction: Restenosis after carotid endarterectomy (CEA) has been described in 8-19% of patients, 14-23% of whom become symptomatic. This study analyzes our experience with carotid artery stenting (CAS) for post-CEA recurrent stenoses.MethodRetrospective database and case-note review. Results: Between January 2000 and September 2008, a total of 27 patients (15 symptomatic) with hemodynamically significant internal carotid artery post-CEA restenosis underwent CAS. Median stenosis of target vessels was 90% (range 75-95%). There was one periprocedural death (3.7%); no others occurred during the median 34-month follow-up (range 0.1-84 months). There was one late transient ischemic attack 12 months after CAS that was notmore » associated with in-stent restenosis. One 90% restenosis and one occlusion were detected during follow-up at 38 and 57 months after CAS. The remaining patients had no evidence of further restenosis and remained free from cerebrovascular symptoms. Conclusion: CAS offers a feasible option for the management of carefully selected patients with symptomatic and asymptomatic restenosis after CEA.« less

Association between Micronutrients Intake/Status and Carotid Intima Media Thickness: A Systematic Review.

PubMed

Hosseini, Banafshe; Saedisomeolia, Ahmad; Skilton, Michael R

2017-01-01

Carotid intima media thickness (IMT) is a noninvasive marker of the extent and severity of subclinical atherosclerosis. Micronutrient intake may affect atherosclerosis and play a major role in the development of cardiovascular diseases (CVDs). The primary aim of this review was to synthesize the evidence regarding the association between carotid IMT and selected micronutrients. The authors searched PubMed, Cochrane, and EMBASE databases from inception to June 2016 for selected micronutrients, CVD, carotid IMT, and antioxidants. Thirty-five original studies met the inclusion criteria and were reviewed following preferred reporting items for systematic review and meta-analysis guidelines. Although not all studies found consistent results, the weight of the evidence suggests that high intakes and/or circulatory levels of magnesium, as well as vitamin D and the vitamin B group, may be associated with lower carotid IMT or reduced progression of carotid IMT. The majority of studies did not find any significant association between vitamin E and C and carotid IMT. Less evidence was available for associations of retinol, zinc, and iron with carotid IMT. In general, the current evidence concerning micronutrient intake and carotid IMT is largely inconclusive. Pragmatic clinical trials are required to determine whether dietary or supplemental intake of specific micronutrients alters carotid IMT, which is a surrogate measure of cardiovascular risk. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Three-dimensional quantitative T1 and T2 mapping of the carotid artery: Sequence design and in vivo feasibility.

PubMed

Coolen, Bram F; Poot, Dirk H J; Liem, Madieke I; Smits, Loek P; Gao, Shan; Kotek, Gyula; Klein, Stefan; Nederveen, Aart J

2016-03-01

A novel three-dimensional (3D) T1 and T2 mapping protocol for the carotid artery is presented. A 3D black-blood imaging sequence was adapted allowing carotid T1 and T2 mapping using multiple flip angles and echo time (TE) preparation times. B1 mapping was performed to correct for spatially varying deviations from the nominal flip angle. The protocol was optimized using simulations and phantom experiments. In vivo scans were performed on six healthy volunteers in two sessions, and in a patient with advanced atherosclerosis. Compensation for patient motion was achieved by 3D registration of the inter/intrasession scans. Subsequently, T1 and T2 maps were obtained by maximum likelihood estimation. Simulations and phantom experiments showed that the bias in T1 and T2 estimation was < 10% within the range of physiological values. In vivo T1 and T2 values for carotid vessel wall were 844 ± 96 and 39 ± 5 ms, with good repeatability across scans. Patient data revealed altered T1 and T2 values in regions of atherosclerotic plaque. The 3D T1 and T2 mapping of the carotid artery is feasible using variable flip angle and variable TE preparation acquisitions. We foresee application of this technique for plaque characterization and monitoring plaque progression in atherosclerotic patients. © 2015 Wiley Periodicals, Inc.

Triglyceride glucose index and common carotid wall shear stress.

PubMed

Tripolino, Cesare; Irace, Concetta; Scavelli, Faustina B; de Franceschi, Maria S; Esposito, Teresa; Carallo, Claudio; Gnasso, Agostino

2014-02-01

Alterations in wall shear stress contribute to both clinical and subclinical atherosclerosis. Several conditions such as hypertension, diabetes, and obesity can impair shear stress, but the role of insulin resistance has never been investigated. The present study was designed to investigate whether insulin resistance assessed by TyG Index associates with wall shear stress in the common carotid artery. One hundred six individuals were enrolled. Blood pressure, lipids, glucose, and cigarette smoking were evaluated. TyG Index was calculated as log[fasting triglycerides × fasting glucose / 2]. Subjects underwent blood viscosity measurement and echo-Doppler evaluation of carotid arteries to calculate wall shear stress. The association between TyG Index and carotid wall shear stress was assessed by simple and multiple regression analyses. TyG Index was significantly and inversely associated with carotid wall shear stress both in simple (r = -0.44, P < 0.001) and multiple regression analyses accounting for age, sex, and major cardiovascular risk factors. The association was further confirmed after exclusion of subjects with diabetes, dyslipidemia, fasting blood glucose greater than 100 mg/dL, and triglycerides greater than 150 mg/dL. The present findings suggest that increasing insulin resistance, as assessed by TyG Index, associates with atherosclerosis-prone shear stress reduction in the common carotid artery.

The distribution of cholinesterases in the cat carotid body

PubMed Central

Biscoe, T. J.; Silver, Ann

1966-01-01

1. The distribution of acetyl- and butyrylcholinesterase in the carotid body of the cat has been examined histochemically. Studies were made on normal carotid bodies and on carotid bodies from cats in which certain nerves had been cut some time previously. The nerves sectioned were the sinus nerve, the post-ganglionic sympathetic branch of the superior cervical ganglion or the preganglionic cervical sympathetic trunk. 2. It was confirmed that more butyrylcholinesterase than acetylcholinesterase is present. Both enzymes are found in three sites: (i) as strands, (ii) as plexuses, (iii) inside a few cells. 3. The distribution is unaffected by cutting the sinus nerve or preganglionic cervical sympathetic nerves. Disorganization and depletion of the cholinesterases in the strands and plexuses occurs when the post-ganglionic branch of the superior cervical ganglion is cut. The cholinesterase in cells is unaffected. 4. In carotid bodies in which vessels were filled with red blood cells or in which the vascular bed was injected with carmine-gelatine, it was seen that strands and plexuses are associated with blood vessels, and with blood vessels and cells respectively. 5. It is suggested that a cholinergic pathway controlling carotid body blood vessels runs in the post-ganglionic cervical sympathetic. ImagesabcdefPlate 2abcdef PMID:5942823

The distribution of cholinesterases in the cat carotid body.

PubMed

Biscoe, T J; Silver, A

1966-03-01

1. The distribution of acetyl- and butyrylcholinesterase in the carotid body of the cat has been examined histochemically. Studies were made on normal carotid bodies and on carotid bodies from cats in which certain nerves had been cut some time previously. The nerves sectioned were the sinus nerve, the post-ganglionic sympathetic branch of the superior cervical ganglion or the preganglionic cervical sympathetic trunk.2. It was confirmed that more butyrylcholinesterase than acetylcholinesterase is present. Both enzymes are found in three sites: (i) as strands, (ii) as plexuses, (iii) inside a few cells.3. The distribution is unaffected by cutting the sinus nerve or preganglionic cervical sympathetic nerves. Disorganization and depletion of the cholinesterases in the strands and plexuses occurs when the post-ganglionic branch of the superior cervical ganglion is cut. The cholinesterase in cells is unaffected.4. In carotid bodies in which vessels were filled with red blood cells or in which the vascular bed was injected with carmine-gelatine, it was seen that strands and plexuses are associated with blood vessels, and with blood vessels and cells respectively.5. It is suggested that a cholinergic pathway controlling carotid body blood vessels runs in the post-ganglionic cervical sympathetic.

[Value of MR imaging and MR angiography in the differential diagnosis of carotid space tumour].

PubMed

Liu, Pei-fang; Li, Xin; Bao, Run-xian; Liu, Jing-zu; Ge, Zheng-jin

2004-04-01

To determine the imaging features of magnetic resonance imaging (MRI) and 2D time of flight (TOF) MR angiography (MRA) and study the value in the differential diagnosis and surgical planning for carotid space tumors. Twenty-six patients with suspected pulsatile carotid space mass were imaged by MRI and 2D TOF MRA from 1996 to 2003. Its characteristic findings were analyzed for lesion shape, margin, signal intensity, angle of common carotid bifurcation, and the relationship between the great vessels and carotid space mass. Of the 26 patients, 22 were verified histopathologically, including 15 carotid body tumors (1 patient had bilateral carotid body tumors), 4 carotid artery aneurysms, 3 schwannomas, and 1 metastatic carcinoma. The rest four patients had clinical pseudomasses proved by MRI and MRA as considerable dilated or tortuous carotid artery as compared with the contralateral one. Combined MRI and MRA assessment of carotid body tumors and carotid artery aneurysm yielded an accuracy of 100%. It was also revealed that the anatomy shown on the MRI and axial MRA source images was consistent with that found by surgery. MRI in combination with MRA is considered as non-invasive imaging technique for the evaluation of carotid space tumor showing superiority to other modalities in the differential diagnosis between vascular versus non-vascular tumours. This method may take the place of traumatic carotid angiography.

Lack of age-related increase in carotid artery wall viscosity in cardiorespiratory fit men

PubMed Central

Kawano, Hiroshi; Yamamoto, Kenta; Gando, Yuko; Tanimoto, Michiya; Murakami, Haruka; Ohmori, Yumi; Sanada, Kiyoshi; Tabata, Izumi; Higuchi, Mitsuru; Miyachi, Motohiko

2013-01-01

Objectives: Age-related arterial stiffening and reduction of arterial elasticity are attenuated in individuals with high levels of cardiorespiratory fitness. Viscosity is another mechanical characteristic of the arterial wall; however, the effects of age and cardiorespiratory fitness have not been determined. We examined the associations among age, cardiorespiratory fitness and carotid arterial wall viscosity. Methods: A total of 111 healthy men, aged 25–39 years (young) and 40–64 years (middle-aged), were divided into either cardiorespiratory fit or unfit groups on the basis of peak oxygen uptake. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the effective compliance, isobaric compliance and viscosity index. Results: In the middle-aged men, the viscosity index was larger in the unfit group than in the fit group (2533 vs. 2018 mmHg·s/mm, respectively: P < 0.05), but this was not the case in the young men. In addition, effective and isobaric compliance were increased, and viscosity index was increased with advancing age, but these parameters were unaffected by cardiorespiratory fitness level. Conclusion: These results suggest that the wall viscosity in the central artery is increased with advancing age and that the age-associated increase in wall viscosity may be attenuated in cardiorespiratory fit men. PMID:24029868

Lack of age-related increase in carotid artery wall viscosity in cardiorespiratory fit men.

PubMed

Kawano, Hiroshi; Yamamoto, Kenta; Gando, Yuko; Tanimoto, Michiya; Murakami, Haruka; Ohmori, Yumi; Sanada, Kiyoshi; Tabata, Izumi; Higuchi, Mitsuru; Miyachi, Motohiko

2013-12-01

Age-related arterial stiffening and reduction of arterial elasticity are attenuated in individuals with high levels of cardiorespiratory fitness. Viscosity is another mechanical characteristic of the arterial wall; however, the effects of age and cardiorespiratory fitness have not been determined. We examined the associations among age, cardiorespiratory fitness and carotid arterial wall viscosity. A total of 111 healthy men, aged 25-39 years (young) and 40-64 years (middle-aged), were divided into either cardiorespiratory fit or unfit groups on the basis of peak oxygen uptake. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the effective compliance, isobaric compliance and viscosity index. In the middle-aged men, the viscosity index was larger in the unfit group than in the fit group (2533 vs. 2018 mmHg·s/mm, respectively: P<0.05), but this was not the case in the young men. In addition, effective and isobaric compliance were increased, and viscosity index was increased with advancing age, but these parameters were unaffected by cardiorespiratory fitness level. These results suggest that the wall viscosity in the central artery is increased with advancing age and that the age-associated increase in wall viscosity may be attenuated in cardiorespiratory fit men.

Carotid angioplasty and stenting under protection. Techniques, results and limitations.

PubMed

Henry, M; Polydorou, A; Henry, I; Anagnostopoulou, I S; Polydorou, I A; Hugel, M

2006-10-01

A carotid stenosis is responsible for about 30% of strokes occurring. Carotid endarterectomy (CEA) is considered to be the gold standard treatment of a carotid stenosis. Carotid angioplasty and stenting (CAS) is emerging as a new alternative treatment for a carotid artery stenosis, but the risk of neurological complications and brain embolism remains the major drawback to this procedure. Therefore, in order to reduce the risks, we need: 1) good indications, good patient and lesion selection; 2) correct techniques; 3) brain protection devices (cerebral protection devices should be routinely used and are mandatory for any procedure); 4) 3 types of protection devices are available, but filters are the most commonly used (all protection devices have limitations and cannot prevent from all embolic events; however, neurological complications can be reduced by 60%); 5) a good choice of the stent and correct implantation (all stents are not equivalent and have different geometrical effects); 6) pharmacological adjuncts; 7) a good team. Recent studies have shown that CAS has superior short-term outcomes than CEA in high surgical risk patients, but there are enough reported data to conclude that CAS is also not inferior to CEA in low-risk patients. CAS under protection is the standard of care and is maybe becoming the gold standard treatment of a carotid stenosis at least in some subgroups of patients.

Are Carotid Stent Fractures Clinically Significant?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garcia-Toca, Manuel; Rodriguez, Heron E.; Naughton, Peter A.

2012-04-15

Purpose: Late stent fatigue is a known complication after carotid artery stenting (CAS) for cervical carotid occlusive disease. The purpose of this study was to determine the prevalence and clinical significance of carotid stent fractures. Materials and Methods: A single-center retrospective review of 253 carotid bifurcation lesions treated with CAS and mechanical embolic protection from April 2001 to December 2009 was performed. Stent integrity was analyzed by two independent observers using multiplanar cervical plain radiographs with fractures classified into the following types: type I = single strut fracture; type II = multiple strut fractures; type III = transverse fracture; andmore » type IV = transverse fracture with dislocation. Mean follow-up was 32 months. Results: Follow-up imaging was completed on 106 self-expanding nitinol stents (26 closed-cell and 80 open-cell stents). Eight fractures (7.5%) were detected (type I n = 1, type II n = 6, and type III n = 1). Seven fractures were found in open-cell stents (Precise n = 3, ViVEXX n = 2, and Acculink n = 2), and 1 fracture was found in a closed-cell stent (Xact n = 1) (p = 0.67). Only a previous history of external beam neck irradiation was associated with fractures (p = 0.048). No associated clinical sequelae were observed among the patients with fractures, and only 1 patient had an associated significant restenosis ({>=}80%) requiring reintervention. Conclusions: Late stent fatigue after CAS is an uncommon event and rarely clinically relevant. Although cell design does not appear to influence the occurrence of fractures, lesion characteristics may be associated risk factors.« less

Management of sizeable carotid body tumor: Case report and review of literature.

PubMed

Elsharawy, Mohamed A; Alsaif, Hind; Elsaid, Aymen; Kredees, Ali

2013-10-01

Carotid body tumor is a paraganglioma derived from the neural crest. It arises from the carotid body which acts as a vascular chemoreceptors and is usually located at the carotid bifurcation. Sizeable (Shamblin III, >5 cm size) tumors are large and typically encase the carotid artery requiring vessel resection and replacement. Management of such tumors carries a high risk of postoperative mortality and morbidity rates specially with regards to neurovascular complications. We report a case of sizeable tumor which was surgically removed with minimal complications.

Management of sizeable carotid body tumor: Case report and review of literature

PubMed Central

Elsharawy, Mohamed A; Alsaif, Hind; Elsaid, Aymen; Kredees, Ali

2013-01-01

Carotid body tumor is a paraganglioma derived from the neural crest. It arises from the carotid body which acts as a vascular chemoreceptors and is usually located at the carotid bifurcation. Sizeable (Shamblin III, >5 cm size) tumors are large and typically encase the carotid artery requiring vessel resection and replacement. Management of such tumors carries a high risk of postoperative mortality and morbidity rates specially with regards to neurovascular complications. We report a case of sizeable tumor which was surgically removed with minimal complications. PMID:24327970

Automated carotid artery intima layer regional segmentation.

PubMed

Meiburger, Kristen M; Molinari, Filippo; Acharya, U Rajendra; Saba, Luca; Rodrigues, Paulo; Liboni, William; Nicolaides, Andrew; Suri, Jasjit S

2011-07-07

Evaluation of the carotid artery wall is essential for the assessment of a patient's cardiovascular risk or for the diagnosis of cardiovascular pathologies. This paper presents a new, completely user-independent algorithm called carotid artery intima layer regional segmentation (CAILRS, a class of AtheroEdge™ systems), which automatically segments the intima layer of the far wall of the carotid ultrasound artery based on mean shift classification applied to the far wall. Further, the system extracts the lumen-intima and media-adventitia borders in the far wall of the carotid artery. Our new system is characterized and validated by comparing CAILRS borders with the manual tracings carried out by experts. The new technique is also benchmarked with a semi-automatic technique based on a first-order absolute moment edge operator (FOAM) and compared to our previous edge-based automated methods such as CALEX (Molinari et al 2010 J. Ultrasound Med. 29 399-418, 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CULEX (Delsanto et al 2007 IEEE Trans. Instrum. Meas. 56 1265-74, Molinari et al 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CALSFOAM (Molinari et al Int. Angiol. (at press)), and CAUDLES-EF (Molinari et al J. Digit. Imaging (at press)). Our multi-institutional database consisted of 300 longitudinal B-mode carotid images. In comparison to semi-automated FOAM, CAILRS showed the IMT bias of -0.035 ± 0.186 mm while FOAM showed -0.016 ± 0.258 mm. Our IMT was slightly underestimated with respect to the ground truth IMT, but showed uniform behavior over the entire database. CAILRS outperformed all the four previous automated methods. The system's figure of merit was 95.6%, which was lower than that of the semi-automated method (98%), but higher than that of the other automated techniques.

Automated carotid artery intima layer regional segmentation

NASA Astrophysics Data System (ADS)

Meiburger, Kristen M.; Molinari, Filippo; Rajendra Acharya, U.; Saba, Luca; Rodrigues, Paulo; Liboni, William; Nicolaides, Andrew; Suri, Jasjit S.

2011-07-01

Evaluation of the carotid artery wall is essential for the assessment of a patient's cardiovascular risk or for the diagnosis of cardiovascular pathologies. This paper presents a new, completely user-independent algorithm called carotid artery intima layer regional segmentation (CAILRS, a class of AtheroEdge™ systems), which automatically segments the intima layer of the far wall of the carotid ultrasound artery based on mean shift classification applied to the far wall. Further, the system extracts the lumen-intima and media-adventitia borders in the far wall of the carotid artery. Our new system is characterized and validated by comparing CAILRS borders with the manual tracings carried out by experts. The new technique is also benchmarked with a semi-automatic technique based on a first-order absolute moment edge operator (FOAM) and compared to our previous edge-based automated methods such as CALEX (Molinari et al 2010 J. Ultrasound Med. 29 399-418, 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CULEX (Delsanto et al 2007 IEEE Trans. Instrum. Meas. 56 1265-74, Molinari et al 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CALSFOAM (Molinari et al Int. Angiol. (at press)), and CAUDLES-EF (Molinari et al J. Digit. Imaging (at press)). Our multi-institutional database consisted of 300 longitudinal B-mode carotid images. In comparison to semi-automated FOAM, CAILRS showed the IMT bias of -0.035 ± 0.186 mm while FOAM showed -0.016 ± 0.258 mm. Our IMT was slightly underestimated with respect to the ground truth IMT, but showed uniform behavior over the entire database. CAILRS outperformed all the four previous automated methods. The system's figure of merit was 95.6%, which was lower than that of the semi-automated method (98%), but higher than that of the other automated techniques.

IL-17A influences essential functions of the monocyte/macrophage lineage and is involved in advanced murine and human atherosclerosis.

PubMed

Erbel, Christian; Akhavanpoor, Mohammadreza; Okuyucu, Deniz; Wangler, Susanne; Dietz, Alex; Zhao, Li; Stellos, Konstantinos; Little, Kristina M; Lasitschka, Felix; Doesch, Andreas; Hakimi, Maani; Dengler, Thomas J; Giese, Thomas; Blessing, Erwin; Katus, Hugo A; Gleissner, Christian A

2014-11-01

Atherosclerosis is a chronic inflammatory disease. Lesion progression is primarily mediated by cells of the monocyte/macrophage lineage. IL-17A is a proinflammatory cytokine, which modulates immune cell trafficking and is involved inflammation in (auto)immune and infectious diseases. But the role of IL-17A still remains controversial. In the current study, we investigated effects of IL-17A on advanced murine and human atherosclerosis, the common disease phenotype in clinical care. The 26-wk-old apolipoprotein E-deficient mice were fed a standard chow diet and treated either with IL-17A mAb (n = 15) or irrelevant Ig (n = 10) for 16 wk. Furthermore, essential mechanisms of IL-17A in atherogenesis were studied in vitro. Inhibition of IL-17A markedly prevented atherosclerotic lesion progression (p = 0.001) by reducing inflammatory burden and cellular infiltration (p = 0.01) and improved lesion stability (p = 0.01). In vitro experiments showed that IL-17A plays a role in chemoattractance, monocyte adhesion, and sensitization of APCs toward pathogen-derived TLR4 ligands. Also, IL-17A induced a unique transcriptome pattern in monocyte-derived macrophages distinct from known macrophage types. Stimulation of human carotid plaque tissue ex vivo with IL-17A induced a proinflammatory milieu and upregulation of molecules expressed by the IL-17A-induced macrophage subtype. In this study, we show that functional blockade of IL-17A prevents atherosclerotic lesion progression and induces plaque stabilization in advanced lesions in apolipoprotein E-deficient mice. The underlying mechanisms involve reduced inflammation and distinct effects of IL-17A on monocyte/macrophage lineage. In addition, translational experiments underline the relevance for the human system. Copyright © 2014 by The American Association of Immunologists, Inc.

IL-17A Influences Essential Functions of the Monocyte/Macrophage Lineage and Is Involved in Advanced Murine and Human Atherosclerosis

PubMed Central

Akhavanpoor, Mohammadreza; Okuyucu, Deniz; Wangler, Susanne; Dietz, Alex; Zhao, Li; Stellos, Konstantinos; Little, Kristina M.; Lasitschka, Felix; Doesch, Andreas; Hakimi, Maani; Dengler, Thomas J.; Giese, Thomas; Blessing, Erwin; Katus, Hugo A.; Gleissner, Christian A.

2014-01-01

Atherosclerosis is a chronic inflammatory disease. Lesion progression is primarily mediated by cells of the monocyte/macrophage lineage. IL-17A is a proinflammatory cytokine, which modulates immune cell trafficking and is involved inflammation in (auto)immune and infectious diseases. But the role of IL-17A still remains controversial. In the current study, we investigated effects of IL-17A on advanced murine and human atherosclerosis, the common disease phenotype in clinical care. The 26-wk-old apolipoprotein E–deficient mice were fed a standard chow diet and treated either with IL-17A mAb (n = 15) or irrelevant Ig (n = 10) for 16 wk. Furthermore, essential mechanisms of IL-17A in atherogenesis were studied in vitro. Inhibition of IL-17A markedly prevented atherosclerotic lesion progression (p = 0.001) by reducing inflammatory burden and cellular infiltration (p = 0.01) and improved lesion stability (p = 0.01). In vitro experiments showed that IL-17A plays a role in chemoattractance, monocyte adhesion, and sensitization of APCs toward pathogen-derived TLR4 ligands. Also, IL-17A induced a unique transcriptome pattern in monocyte-derived macrophages distinct from known macrophage types. Stimulation of human carotid plaque tissue ex vivo with IL-17A induced a proinflammatory milieu and upregulation of molecules expressed by the IL-17A–induced macrophage subtype. In this study, we show that functional blockade of IL-17A prevents atherosclerotic lesion progression and induces plaque stabilization in advanced lesions in apolipoprotein E–deficient mice. The underlying mechanisms involve reduced inflammation and distinct effects of IL-17A on monocyte/macrophage lineage. In addition, translational experiments underline the relevance for the human system. PMID:25261478

Extracranial carotid angioplasty and stenting. Initial results and short-term follow-up.

PubMed

Vozzi, C R; Rodriguez, A O; Paolantonio, D; Smith, J A; Wholey, M H

1997-01-01

Carotid percutaneous transluminal angioplasty, with or without stent implantation, is becoming another therapeutic option for carotid revascularization. To evaluate the feasibility and effectiveness of the technique, from October of 1995 to March of 1997, we performed 24 percutaneous transluminal angioplasty procedures in 22 patients with severe extracranial carotid artery stenosis. Three common carotid and 21 internal carotid arteries were treated, and 19 procedures included stent implantation using nonarticulated PALMAZ stents (P154 and P204). Twelve patients were asymptomatic and 10 patients were symptomatic; 2 of the symptomatic patients had complete obstruction of the internal carotid artery that was successfully recanalized. Technical and angiographic success was achieved in 23 of 24 procedures, with the carotid artery obstruction diminishing from 85.6% +/- 8.5% to 5.7% +/- 3.2% (P < 0.001). Average stenosis length was 12.5 +/- 3.1 mm, and mean time of carotid occlusion during balloon inflation was 11.5 +/- 2.5 seconds. Three patients experienced transitory seizures during the procedure prior to dilation, 1 patient had a minor stroke with complete recovery within 72 hours, and 1 patient had a major stroke and died 45 days after the procedure. Clinical follow-up was achieved in all patients (mean, 10.5 +/- 7.2 months) and angiographic follow-up in 16 patients (mean, 6.3 +/- 1.2 months). The results obtained in this initial experience provide adequate support to continue further evaluation of this new therapeutic strategy.

Increased tissue factor, MMP-8, and D-dimer expression in diabetic patients with unstable advanced carotid atherosclerosis.

PubMed

Krupinski, Jerzy; Turu, Marta M; Font, M Angels; Ahmed, Nesser; Sullivan, Matthew; Rubio, Francisco; Badimon, Lina; Slevin, Mark

2007-01-01

Advanced atherogenesis is characterized by the presence of markers of enhanced prothrombotic capacity, attenuated fibrinolysis, and by clinical conditions associated with defective coagulation. Diabetes may be associated with enhanced lesion instability and atherosclerotic plaque rupture. Plaques obtained from 206 patients undergoing carotid endarterectomy were divided into diabetic (type 2) and nondiabetic and analyzed by Western blotting and immunohistochemistry to detect tissue factor (TF), metalloproteinases (MMP)-2, -8, -9, and fibrin/fibrinogen related antigens, and in situ zymography to detect MMP activity. Plasma samples were quantified for TF procoagulant activity, C-reactive protein, fibrinogen and D-dimer. Diabetic and symptomatic patients with hypoechogenic plaques had increased plasma TF activity and D-dimer, compared with those with hyperechogenic plaques (p = 0.03, p = 0.007, respectively). Diabetic, symptomatic patients had higher plasma D-dimer levels than asymptomatic patients (p = 0.03). There was a significant correlation between intramural TF levels and D-dimer in diabetic patients with symptomatic disease (p = 0.001, r2 = 0.4). In diabetic patients, plasma fibrinogen levels were higher in patients with hypoechogenic plaques (p = 0.007). Diabetic patients with ulcerated plaques had higher plasma D-dimer and MMP-8 levels than those with fibrous plaques (p = 0.02, p = 0.01, respectively). This data suggests that currently available circulating markers may be clinically useful to select diabetic patients at higher risk of atherothrombosis. Increased procoagulant activity in diabetic patients may be linked to increased mural remodeling.

Relationship between the Direction of Ophthalmic Artery Blood Flow and Ocular Microcirculation before and after Carotid Artery Stenting.

PubMed

Ishii, Masashi; Hayashi, Morito; Yagi, Fumihiko; Sato, Kenichiro; Tomita, Goji; Iwabuchi, Satoshi

2016-01-01

When internal carotid artery stenosis is accompanied by ocular ischemic syndrome, intervention is recommended to prevent irreversible visual loss. In this study, we used laser speckle flowgraphy to measure the ocular microcirculation in the optic nerve head before and after carotid artery stenting (CAS) of 40 advanced internal carotid stenosis lesions from 37 patients. The aim was to investigate the relationship between ocular microcirculation and the direction of ophthalmic artery blood flow obtained by angiography. We found that there was a significant increase in blood flow after CAS ( P = 0.003). Peak systolic velocity as an indicator of the rate of stenosis was also significantly higher in the group with retrograde/undetected flow of the ophthalmic artery than in the group with antegrade flow ( P = 0.002). In all cases where retrograde flow of the ophthalmic artery was observed before stenting, the flow changed to antegrade after stenting. Through the use of laser speckle flowgraphy, this study found that CAS can improve ocular microcirculation. Furthermore, while patients displaying retrograde flow of the ophthalmic artery before stenting have a poor prognosis, CAS corrected the flow to antegrade, suggesting that visual loss can be prevented by improving the ocular microcirculation.

Carotid-cardiac baroreflex influence on forearm vascular resistance during low level LBNP

NASA Technical Reports Server (NTRS)

Ludwig, David

1990-01-01

Twelve healthy males were tested at low levels of lower body negative pressure (LBNP) with and without artificial stimulation of the carotid-cardiac baroreceptors. The carotid-cardiac baroreceptors were stimulated by applying a pressure of 10 mmHg to the carotid artery via a pressurized neck chamber. During the procedure, forearm blood flow (FBF) and forearm vascular resistance (FVR) were measured using a Whitney mercury silastic strain gauge technique. FBF decreased while FVR increased with increased intensity of LBNP. Both FBF and FVR were unaffected by carotid-cardiac baroreceptor stimulation.

Low concentrations of folate, not hyperhomocysteinemia, are associated with carotid intima-media thickness.

PubMed

Durga, Jane; Bots, Michiel L; Schouten, Evert G; Kok, Frans J; Verhoef, Petra

2005-04-01

We examined whether total homocysteine, B vitamins and the 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C-->T polymorphism are related to common carotid intima-media thickness, a marker of atherosclerosis, and carotid distension, a marker of arterial stiffness. We used cross-sectional data from 819 individuals aged 50-70 years. B-mode ultrasound of the distal common carotid arteries was performed to determine maximum carotid intima-media thickness, mean carotid intima-media thickness and distension. Carotid intima-media thickness and distension did not differ across homocysteine, serum folate, vitamin B(6) and vitamin B(12) quartiles or between MTHFR C677T genotype. Erythrocyte folate was independently associated with maximum carotid intima-media thickness (mean difference first versus third quartile, 0.03 mm, 95% CI 0.004-0.06 mm; first versus fourth quartile, 0.03 mm, 95% CI -0.002 to 0.06 mm). Further adjustment for homocysteine did not affect this association. Folate deficient subjects had greater maximum carotid intima-media thickness than those with high-normal folate concentrations (serum folate: mean difference 0.05 mm, 95% CI 0.01-0.08 mm; erythrocyte folate: mean difference 0.04 mm, 95% CI -0.03 to 0.11 mm). Low folate concentrations, independent of hyperhomocysteinemia, may promote atherogenesis. Our findings confirm the null association of homocysteine with carotid intima-media thickness observed in other population-based studies, suggesting that hyperhomocysteinemia does not perpetuate atherosclerosis or arterial stiffness.

Linear and Nonlinear Viscoelastic Modeling of Aorta and Carotid Pressure-Area Dynamics under in vivo and ex vivo Conditions

PubMed Central

Valdez-Jasso, Daniela; Bia, Daniel; Zócalo, Yanina; Armentano, Ricardo L.; Haider, Mansoor A.; Olufsen, Mette S.

2013-01-01

A better understanding of the biomechanical properties of the arterial wall provides important insight into arterial vascular biology under normal (healthy) and pathological conditions. This insight has potential to improve tracking of disease progression and to aid in vascular graft design and implementation. In this study, we use linear and nonlinear viscoelastic models to predict biomechanical properties of the thoracic descending aorta and the carotid artery under ex vivo and in vivo conditions in ovine and human arteries. Models analyzed include a four-parameter (linear) Kelvin viscoelastic model and two five-parameter nonlinear viscoelastic models (an arctangent and a sigmoid model) that relate changes in arterial blood pressure to the vessel cross-sectional area (via estimation of vessel strain). These models were developed using the framework of Quasilinear Viscoelasticity (QLV) theory and were validated using measurements from the thoracic descending aorta and the carotid artery obtained from human and ovine arteries. In vivo measurements were obtained from ten ovine aortas and ten human carotid arteries. Ex vivo measurements (from both locations) were made in eleven male Merino sheep. Biomechanical properties were obtained through constrained estimation of model parameters. To further investigate the parameter estimates we computed standard errors and confidence intervals and we used analysis of variance to compare results within and between groups. Overall, our results indicate that optimal model selection depends on the arterial type. Results showed that for the thoracic descending aorta (under both experimental conditions) the best predictions were obtained with the nonlinear sigmoid model, while under healthy physiological pressure loading the carotid arteries nonlinear stiffening with increasing pressure is negligible, and consequently, the linear (Kelvin) viscoelastic model better describes the pressure-area dynamics in this vessel. Results

A simple technique to achieve bloodless excision of carotid body tumors.

PubMed

Spinelli, Francesco; Massara, Mafalda; La Spada, Michele; Stilo, Francesco; Barillà, David; De Caridi, Giovanni

2014-05-01

We describe a technique for Shamblin II-III carotid body tumor (CBT) resection to reduce bleeding and neurologic complications during surgery. The technique was based on the fact that CBTs are supplied almost exclusively from the external carotid artery. Therefore, we carefully isolated the origin of the external carotid artery and its distal branches outside the tumor and temporarily clamped all of these vessels after heparin administration. This allowed a safe and bloodless resection as the tumor was dissected from the internal carotid artery in the usual subadventitial plane. The internal carotid artery was never clamped, and respect of peripheral nerves was warranted in the clean and bloodless field. From 2007 to 2010, we treated 11 patients with a CBT: six had a Shamblin II and five had a Shamblin III lesion. Neither perioperative neurologic events nor recurrences occurred after a mean follow-up of 42 months. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Hybrid treatment of common carotid artery occlusion with ring-stripper endarterectomy plus stenting.

PubMed

Pintér, László; Cagiannos, Catherine; Bakoyiannis, Chris N; Kolvenbach, Ralf

2007-07-01

Symptomatic occlusion of the common carotid artery with preserved circulation in the internal carotid artery is an uncommon occurrence. We describe a hybrid technique whereby a patient was treated with eversion carotid bifurcation endarterectomy, fluoroscopically guided retrograde ring-stripper common carotid endarterectomy, and stenting of residual stenosis in the disobliterated artery. Successful recanalization was achieved without adverse anatomic or neurologic sequelae. The patient remains asymptomatic with a radiographically patent reconstruction at 1 year. This combination of endovascular and open surgery enables the surgeon to address long occlusions of the common carotid arteries with control of the distal and proximal endarterectomy margins and obviates the need for general anesthesia or sternotomy.

Radical resection of a Shamblin type III carotid body tumour without cerebro-neurological deficit: Improved technique with preoperative embolization and carotid stenting.

PubMed

Ong, H S; Fan, X D; Ji, T

2014-12-01

The surgical resection of a large unfavourable Shamblin type III carotid body tumour (CBT) can be very challenging technically, with many potential significant complications. Preoperative embolization aids in shrinking the lesion, reducing intraoperative blood loss, and improving visualization of the surgical field. Preoperative internal carotid artery (ICA) stenting aids in reinforcing the arterial wall, thereby providing a better dissection plane. A woman presented to our institution with a large right-sided CBT. Failure of the preoperative temporary balloon occlusion (TBO) test emphasized the importance of intraoperative preservation of the ipsilateral ICA. A combination of both preoperative embolization and carotid stenting allowed a less hazardous radical resection of the CBT. An almost bloodless surgical field permitted meticulous dissection, hence reducing the risk of intraoperative vascular and nerve injury. Embolization and carotid stenting prior to surgical resection should be considered in cases with bilateral CBT or a skull base orientated high CBT, and for those with intracranial extension and patients who have failed the TBO test. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Three-dimensional power Doppler sonography in screening for carotid artery disease.

PubMed

Keberle, M; Jenett, M; Beissert, M; Jahns, R; Haerten, R; Hahn, D

2000-01-01

Color Doppler sonography has gained considerable recognition as a noninvasive method to detect carotid artery disease and to assess the degree of carotid artery stenosis. However, results are highly operator-dependent and cannot be presented as survey images. The purpose of this study was to evaluate real-time 3-dimensional (3D) power Doppler sonography as a method for screening for atherosclerosis in the carotid arteries. We prospectively screened 75 patients for carotid artery disease using both conventional color Doppler sonography and 3D power Doppler sonography, and the results from the 2 modalities were compared. A total of 150 common carotid arteries, 150 internal carotid arteries, and 150 external carotid arteries were examined utilizing a 7.5-MHz linear-array transducer combined with tissue harmonic imaging. Color Doppler sonography detected 297 normal or atherosclerotic arteries without stenosis, 57 arteries with mild (1-49%) stenosis, 41 with moderate (50-69%) stenosis, 32 with severe (70-99%) stenosis, and 9 with occlusions. The degree of stenosis determined by color Doppler sonography correlated with that determined by 3D power Doppler sonography (r = 0.982-0.998). Moreover, there was a good correlation between the measurements for both the length of the lesion and its distance from the bulb as determined by the 3D volume surveys and by color Doppler sonography (r = 0.986). The interobserver variability rate was 3.7% +/- 0.5%. Generally, the acquisition and reconstruction of the 3D data took less than 5 minutes. 3D power Doppler sonography is easy to perform and is an accurate method in screening for atherosclerotic lesions of the carotid arteries. Moreover, it provides excellent 3D volume surveys that may be helpful in the planning of surgical treatment. Copyright 2000 John Wiley & Sons, Inc.

Habitual fish intake and clinically silent carotid atherosclerosis

PubMed Central

2014-01-01

Background Fish consumption is recommended as part of a healthy diet. However, there is a paucity of data concerning the relation between fish consumption and carotid atherosclerosis. We investigated the association between habitual fish consumption and asymptomatic carotid atherosclerosis, defined as the presence of plaques and/or increased intima-media thickness (≥ 0.90 mm), in non-diabetic participants. Methods Nine hundred-sixty-one (range of age: 18–89 yrs; 37.1% males) adult participants without clinically known atherosclerotic disease were randomly recruited among the customers of a shopping mall in Palermo, Italy, and cross-sectionally investigated. Each participant answered a food frequency questionnaire and underwent high-resolution ultrasonographic evaluation of both carotid arteries. Routine laboratory blood measurements were obtained in a subsample of 507 participants. Results Based on habitual fish consumption, participants were divided into three groups: non-consumers or consumers of less than 1 serving a week (24.0%), consumers of 1 serving a week (38.8%), and consumers of ≥ 2 servings a week (37.2%). Age-adjusted prevalence of carotid atherosclerosis (presence of plaques or intima media thickness ≥ 0.9 mm) was higher in the low fish consumption group (13.3%, 12.1% and 6.6%, respectively; P = 0.003). Multivariate analysis evidenced that carotid atherosclerosis was significantly associated with age (OR = 1.12; 95% CI = 1.09-1.14), hypertension on pharmacologic treatment (OR = 1.81; 95% CI = 1.16-2.82), and pulse pressure (OR = 1.03; 95% CI = 1.01-1.04), while consuming ≥2 servings of fish weekly was protective compared with the condition of consumption of <1 serving of fish weekly (OR = 0.46; 95% CI = 0.26-0.80). Conclusions High habitual fish consumption seems to be associated with less carotid atherosclerosis, though adequate interventional trials are necessary to confirm the role of fish

Habitual fish intake and clinically silent carotid atherosclerosis.

PubMed

Buscemi, Silvio; Nicolucci, Antonio; Lucisano, Giuseppe; Galvano, Fabio; Grosso, Giuseppe; Belmonte, Serena; Sprini, Delia; Migliaccio, Silvia; Cianferotti, Luisella; Brandi, Maria Luisa; Rini, Giovam Battista

2014-01-09

Fish consumption is recommended as part of a healthy diet. However, there is a paucity of data concerning the relation between fish consumption and carotid atherosclerosis. We investigated the association between habitual fish consumption and asymptomatic carotid atherosclerosis, defined as the presence of plaques and/or increased intima-media thickness (≥ 0.90 mm), in non-diabetic participants. Nine hundred-sixty-one (range of age: 18-89 yrs; 37.1% males) adult participants without clinically known atherosclerotic disease were randomly recruited among the customers of a shopping mall in Palermo, Italy, and cross-sectionally investigated. Each participant answered a food frequency questionnaire and underwent high-resolution ultrasonographic evaluation of both carotid arteries. Routine laboratory blood measurements were obtained in a subsample of 507 participants. Based on habitual fish consumption, participants were divided into three groups: non-consumers or consumers of less than 1 serving a week (24.0%), consumers of 1 serving a week (38.8%), and consumers of ≥ 2 servings a week (37.2%). Age-adjusted prevalence of carotid atherosclerosis (presence of plaques or intima media thickness ≥ 0.9 mm) was higher in the low fish consumption group (13.3%, 12.1% and 6.6%, respectively; P = 0.003). Multivariate analysis evidenced that carotid atherosclerosis was significantly associated with age (OR = 1.12; 95% CI = 1.09-1.14), hypertension on pharmacologic treatment (OR = 1.81; 95% CI = 1.16-2.82), and pulse pressure (OR = 1.03; 95% CI = 1.01-1.04), while consuming ≥2 servings of fish weekly was protective compared with the condition of consumption of <1 serving of fish weekly (OR = 0.46; 95% CI = 0.26-0.80). High habitual fish consumption seems to be associated with less carotid atherosclerosis, though adequate interventional trials are necessary to confirm the role of fish consumption in prevention of cardiovascular

In the carotid body, galanin is a signal for neurogenesis in young, and for neurodegeneration in the old and in drug-addicted subjects

PubMed Central

Mazzatenta, Andrea; Marconi, Guya D.; Zara, Susi; Cataldi, Amelia; Porzionato, Andrea; Di Giulio, Camillo

2014-01-01

The carotid body is a highly specialized chemoreceptive structure for the detection of and reaction to hypoxia, through induction of an increase in hypoxia inducible factor. As tissue hypoxia increases with aging and can have dramatic effects in respiratory depression induced by drug addiction, we investigated the carotid body in young and old healthy subjects in comparison with drug-addicted subjects, including the expression of the neurotransmitter galanin. Galanin expression was recently reported for neuronal-like cells of the human carotid body, and it is implicated in several functions in neurons. In particular, this includes the regulation of differentiation of neural stem cells, and participation in the development and plasticity of the nervous system. Using immunohistochemistry detection, we demonstrate that galanin expression in the human carotid body in healthy older subjects and drug-addicted subjects is significantly reduced in comparison with healthy young subjects. This demonstrates not only the effects of normal aging and senescence, but also in the drug-addicted subjects, this appears to be due to a disorganization of the chemo-sensory region. With both aging and drug addiction, this results in a physiological reduction in neuronal-like cells, coupled with interlobular and intralobular increases in connective tissue fibers. Consequently, in both aging and drug addiction, this reduction of neuronal-like cells and the regeneration suggest that the carotid body is losing its sensory capabilities, with the transmission of chemoreceptive signals dramatically and vitally reduced. The level of galanin expression would thus provide a signal for neurogenesis in young subjects, and for neurodegeneration in older and drug-addicted subjects. PMID:25400591

Standard duplex criteria overestimate the degree of stenosis after eversion carotid endarterectomy.

PubMed

Benzing, Travis; Wilhoit, Cameron; Wright, Sharee; McCann, P Aaron; Lessner, Susan; Brothers, Thomas E

2015-06-01

The eversion technique for carotid endarterectomy (eCEA) offers an alternative to longitudinal arteriotomy and patch closure (pCEA) for open carotid revascularization. In some reports, eCEA has been associated with a higher rate of >50% restenosis of the internal carotid when it is defined as peak systolic velocity (PSV) >125 cm/s by duplex imaging. Because the conformation of the carotid bifurcation may differ after eCEA compared with native carotid arteries, it was hypothesized that standard duplex criteria might not accurately reflect the presence of restenosis after eCEA. In a case-control study, the outcomes of all patients undergoing carotid endarterectomy by one surgeon during the last 10 years were analyzed retrospectively, with a primary end point of PSV >125 cm/s. Duplex flow velocities were compared with luminal diameter measurements for any carotid computed tomography arteriography or magnetic resonance angiography study obtained within 2 months of duplex imaging, with the degree of stenosis calculated by the methodology used in the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (ECST) as well as cross-sectional area (CSA) reduction. Simulations were generated and analyzed by computational model simulations of the eCEA and pCEA arteries. Eversion and longitudinal arteriotomy with patch techniques were used in 118 and 177 carotid arteries, respectively. Duplex follow-up was available in 90 eCEA arteries at a median of 16 (range, 2-136) months and in 150 pCEA arteries at a median of 41 (range, 3-115) months postoperatively. PSV >125 cm/s was present at some time during follow-up in 31% of eCEA and pCEA carotid arteries, each, and in the most recent duplex examination in 7% after eCEA and 21% after pCEA (P = .003), with no eCEA and two pCEA arteries occluding completely during follow-up (P = .29). In 19 carotid arteries with PSV >125 cm/s after angle correction (median, 160 cm/s; interquartile range

Reference values of one-point carotid stiffness parameters determined by carotid echo-tracking and brachial pulse pressure in a large population of healthy subjects.

PubMed

Vriz, Olga; Aboyans, Victor; Minisini, Rosalba; Magne, Julien; Bertin, Nicole; Pirisi, Mario; Bossone, Eduardo

2017-07-01

Arterial stiffness can predict cardiovascular events, and the aim of this study was to produce age- and sex-specific reference values for echo-tracking carotid stiffness in healthy subjects. A total of 900 subjects (500 males, mean age 45.8±19 years) were enrolled. Common carotid artery stiffness and compliance, using a high-definition echo-tracking ultrasound system, were evaluated. To compare stiffness parameters across the different age groups, individual scores were transformed into T-scores, indicating how many standard deviation (s.d.) units an individual's score was above or below the mean that was observed in the group including same-sex individuals aged 36 to 44 years. Carotid stiffness was similar among genders, except compliance, which was lower in women (P<0.0001). These characteristics were also maintained when the studied population was divided into seven age groups. Stiffness parameters increased significantly with age, but the opposite occurred for compliance. The T-score was found to increase significantly across all age groups, with a steeper increase in stiffness around the age of 60 years in women. For each T-score s.d., the corresponding carotid absolute values for arterial stiffness and compliance were obtained. In a multivariate model, carotid stiffness parameters were constantly and independently associated with age, mean arterial pressure, pulse pressure, heart rate and body mass index. Our study provides a normogram of carotid arterial stiffness and compliance indices obtained with the echo-tracking method in a large population of healthy subjects stratified by gender and age that can be used in clinical practice.

Relationship between adult height and body weight and risk of carotid atherosclerosis assessed in terms of carotid intima-media thickness: The Nagasaki Islands study

PubMed Central

2013-01-01

Background Previous studies have reported an inverse association between height and risk of cardiovascular disease. However, evidence is limited for the association between risk of atherosclerosis and height. Further, although the association between atherosclerosis and body mass index (BMI) is reportedly positive, there have been no reports of studies on associations between height and atherosclerosis in relation to BMI. Methods We conducted a cross-sectional study of Japanese men aged 30 to 89 years undergoing general health check-ups. Results Of the 1,337 men, 312 were diagnosed with carotid atherosclerosis (carotid intima-media thickness (CIMT) ≥ 1.1 mm), but no significant association was found between height and carotid atherosclerosis for the entire study group. Stratification by BMI status of those analytical findings disclosed a significant inverse association between height and carotid atherosclerosis among overweight (BMI ≥ 25 kg/m2) but not among non-overweight (BMI < 25 kg/m2) men. The classical cardiovascular risk factors-adjusted odds ratio (OR) and 95% confidence interval (CI) of carotid atherosclerosis for an increment of one SD (standard deviation) in height (6.70 cm) were 0.71 (0.54 to 0.94) for overweight (BMI ≥ 25 kg/m2) and 1.05 (0.87 to 1.27) for non-overweight (BMI < 25 kg/m2) men. Conclusion Independent from classical cardiovascular risk factors, height was found to be inversely associated with carotid atherosclerosis for overweight but not for non-overweight men. PMID:24180493

Carotid intima media thickness and plaques can predict the occurrence of ischemic cerebrovascular events.

PubMed

Prati, Patrizio; Tosetto, Alberto; Vanuzzo, Diego; Bader, Giovanni; Casaroli, Marco; Canciani, Luigi; Castellani, Sergio; Touboul, Pierre-Jean

2008-09-01

The clinical usefulness of noninvasive measurement of carotid intima media thickness and plaque visualization in the general population is still uncertain. We evaluated the age-specific incidence rates of cerebrovascular events in a cohort of 1348 subjects randomly taken from the census list of San Daniele Township and followed for a mean period of 12.7 years. The association among common carotid intima media thickness, measured at baseline, arterial risk factors, and incidence of ischemic cerebrovascular events was modeled using Poisson regression. The predictive ability of common carotid intima media thickness over arterial risk factors (summarized in the Framingham Stroke Risk Score) was evaluated by receiver operating characteristic curve analysis. During the follow-up, 115 subjects developed nonfatal ischemic stroke, transient ischemic attack, or vascular death, which were the predefined study end points. After adjustment for age and sex, hypertension, diabetes, common carotid intima media thickness above 1 mm, and carotid plaques were all independent risk factors for development of vascular events. Inclusion of carotid findings (presence of common carotid intima media thickness above 1 mm or carotid plaques) resulted in a predictive power higher than Framingham Stroke Risk Score alone only on for those subjects with a Framingham Stroke Risk Score over 20%. Although common carotid intima media thickness and presence of carotid plaques are known to be risk factors for the development of vascular events and to be independent from the conventional risk factors summarized in the Framingham Stroke Risk Score, their contribution to individual risk prediction is limited. Further studies will be required to address the role of carotid ultrasonography in the primary prevention of high-risk subjects.

Risk Factors For Stroke, Myocardial Infarction, or Death Following Carotid Endarterectomy: Results From the International Carotid Stenting Study.

PubMed

Doig, D; Turner, E L; Dobson, J; Featherstone, R L; de Borst, G J; Stansby, G; Beard, J D; Engelter, S T; Richards, T; Brown, M M

2015-12-01

Carotid endarterectomy (CEA) is standard treatment for symptomatic carotid artery stenosis but carries a risk of stroke, myocardial infarction (MI), or death. This study investigated risk factors for these procedural complications occurring within 30 days of endarterectomy in the International Carotid Stenting Study (ICSS). Patients with recently symptomatic carotid stenosis >50% were randomly allocated to endarterectomy or stenting. Analysis is reported of patients in ICSS assigned to endarterectomy and limited to those in whom CEA was initiated. The occurrence of stroke, MI, or death within 30 days of the procedure was reported by investigators and adjudicated. Demographic and technical risk factors for these complications were analysed sequentially in a binomial regression analysis and subsequently in a multivariable model. Eight-hundred and twenty-one patients were included in the analysis. The risk of stroke, MI, or death within 30 days of CEA was 4.0%. The risk was higher in female patients (risk ratio [RR] 1.98, 95% CI 1.02-3.87, p = .05) and with increasing baseline diastolic blood pressure (dBP) (RR 1.30 per +10 mmHg, 95% CI 1.02-1.66, p = .04). Mean baseline dBP, obtained at the time of randomization in the trial, was 78 mmHg (SD 13 mmHg). In a multivariable model, only dBP remained a significant predictor. The risk was not related to the type of surgical reconstruction, anaesthetic technique, or perioperative medication regimen. Patients undergoing CEA stayed a median of 4 days before discharge, and 21.2% of events occurred on or after the day of discharge. Increasing diastolic blood pressure was the only independent risk factor for stroke, MI, or death following CEA. Cautious attention to blood pressure control following symptoms attributable to carotid stenosis could reduce the risks associated with subsequent CEA. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Perspective: carotid stenting and the history of disruptive technology in vascular surgery.

PubMed

Veith, Frank J

2008-06-01

This article defines disruptive technology and discusses such technologies in Vascular Surgery. It considers the question: Is carotid artery stenting (CAS) a disruptive technology? Although CAS will impact positively on the treatment of carotid bifurcation disease, it will probably never displace carotid endarterectomy in the majority of patients. The precise role of CAS remains to be determined.

Evaluation of the carotid artery stenosis based on minimization of mechanical energy loss of the blood flow.

PubMed

Sia, Sheau Fung; Zhao, Xihai; Li, Rui; Zhang, Yu; Chong, Winston; He, Le; Chen, Yu

2016-11-01

Internal carotid artery stenosis requires an accurate risk assessment for the prevention of stroke. Although the internal carotid artery area stenosis ratio at the common carotid artery bifurcation can be used as one of the diagnostic methods of internal carotid artery stenosis, the accuracy of results would still depend on the measurement techniques. The purpose of this study is to propose a novel method to estimate the effect of internal carotid artery stenosis on the blood flow based on the concept of minimization of energy loss. Eight internal carotid arteries from different medical centers were diagnosed as stenosed internal carotid arteries, as plaques were found at different locations on the vessel. A computational fluid dynamics solver was developed based on an open-source code (OpenFOAM) to test the flow ratio and energy loss of those stenosed internal carotid arteries. For comparison, a healthy internal carotid artery and an idealized internal carotid artery model have also been tested and compared with stenosed internal carotid artery in terms of flow ratio and energy loss. We found that at a given common carotid artery bifurcation, there must be a certain flow distribution in the internal carotid artery and external carotid artery, for which the total energy loss at the bifurcation is at a minimum; for a given common carotid artery flow rate, an irregular shaped plaque at the bifurcation constantly resulted in a large value of minimization of energy loss. Thus, minimization of energy loss can be used as an indicator for the estimation of internal carotid artery stenosis.

Factors Influencing Decision Making for Carotid Endarterectomy versus Stenting in the Very Elderly

PubMed Central

Heo, Sung Hyuk; Bushnell, Cheryl D.

2017-01-01

As the population ages worldwide, the number of elderly patients with carotid stenosis is also increasing. There have been many large clinical trials comparing carotid endarterectomy (CAE) versus stenting, but the inclusion criteria (i.e., symptomatic or asymptomatic), stenting methods (i.e., protection device), and primary end point (i.e., the definition of myocardial infarction and follow-up period) were different between trials. Therefore, the interpretation of those results is difficult and requires attention. When it comes to age, the patients older than 80 years were excluded or stratified to a high risk group in previous landmark trials. However, a recent guideline recommended that endarterectomy may be associated with lower stroke risk compared with carotid artery stenting in patients older than 70 years with symptomatic carotid disease. The annual risk of stroke in individuals with asymptomatic carotid stenosis is about 1–3% but the risk is about 4–12% with symptomatic stenosis without carotid intervention. Although the outcome of CAE is better than that of carotid stenting in patients older than 70 years, the perioperative risk is higher in older patients. Therefore, it is important to classify high risk patients and consider underlying disability and life expectancy of very elderly patients before deciding whether to undergo a carotid intervention. In addition, we should also consider that the stroke rate with intensive medical treatment is unknown and is currently being investigated in randomized controlled trials. Intensive medical treatment includes high intensity statins, diabetes and blood pressure control, and aggressive antiplatelet treatment. The aim of this review is to report the factors that may be responsible for the variability in the treatment of carotid stenosis, particularly in the elderly population. This will allow the readers to integrate the current available evidence to individualize the treatment of carotid stenosis in

Systematic Review of Guidelines for the Management of Asymptomatic and Symptomatic Carotid Stenosis.

PubMed

Abbott, Anne L; Paraskevas, Kosmas I; Kakkos, Stavros K; Golledge, Jonathan; Eckstein, Hans-Henning; Diaz-Sandoval, Larry J; Cao, Longxing; Fu, Qiang; Wijeratne, Tissa; Leung, Thomas W; Montero-Baker, Miguel; Lee, Byung-Chul; Pircher, Sabine; Bosch, Marije; Dennekamp, Martine; Ringleb, Peter

2015-11-01

We systematically compared and appraised contemporary guidelines on management of asymptomatic and symptomatic carotid artery stenosis. We systematically searched for guideline recommendations on carotid endarterectomy (CEA) or carotid angioplasty/stenting (CAS) published in any language between January 1, 2008, and January 28, 2015. Only the latest guideline per writing group was selected. Each guideline was analyzed independently by 2 to 6 authors to determine clinical scenarios covered, recommendations given, and scientific evidence used. Thirty-four eligible guidelines were identified from 23 different regions/countries in 6 languages. Of 28 guidelines with asymptomatic carotid artery stenosis procedural recommendations, 24 (86%) endorsed CEA (recommended it should or may be provided) for ≈50% to 99% average-surgical-risk asymptomatic carotid artery stenosis, 17 (61%) endorsed CAS, 8 (29%) opposed CAS, and 1 (4%) endorsed medical treatment alone. For asymptomatic carotid artery stenosis patients considered high-CEA-risk because of comorbidities, vascular anatomy, or undefined reasons, CAS was endorsed in 13 guidelines (46%). Thirty-one of 33 guidelines (94%) with symptomatic carotid artery stenosis procedural recommendations endorsed CEA for patients with ≈50% to 99% average-CEA-risk symptomatic carotid artery stenosis, 19 (58%) endorsed CAS and 9 (27%) opposed CAS. For high-CEA-risk symptomatic carotid artery stenosis because of comorbidities, vascular anatomy, or undefined reasons, CAS was endorsed in 27 guidelines (82%). Guideline procedural recommendations were based only on results of trials in which patients were randomized 12 to 34 years ago, rarely reflected medical treatment improvements and often understated potential CAS hazards. Qualifying terminology summarizing recommendations or evidence lacked standardization, impeding guideline interpretation, and comparison. This systematic review has identified many opportunities to modernize and

Effect of white-matter lesions on the risk of periprocedural stroke after carotid artery stenting versus endarterectomy in the International Carotid Stenting Study (ICSS): a prespecified analysis of data from a randomised trial

PubMed Central

Ederle, Jörg; Davagnanam, Indran; van der Worp, H Bart; Venables, Graham S; Lyrer, Philippe A; Featherstone, Roland L; Brown, Martin M; Jäger, H Rolf

2013-01-01

Summary Background Findings from randomised trials have shown a higher early risk of stroke after carotid artery stenting than after carotid endarterectomy. We assessed whether white-matter lesions affect the perioperative risk of stroke in patients treated with carotid artery stenting versus carotid endarterectomy. Methods Patients with symptomatic carotid artery stenosis included in the International Carotid Stenting Study (ICSS) were randomly allocated to receive carotid artery stenting or carotid endarterectomy. Copies of baseline brain imaging were analysed by two investigators, who were masked to treatment, for the severity of white-matter lesions using the age-related white-matter changes (ARWMC) score. Randomisation was done with a computer-generated sequence (1:1). Patients were divided into two groups using the median ARWMC. We analysed the risk of stroke within 30 days of revascularisation using a per-protocol analysis. ICSS is registered with controlled-trials.com, number ISRCTN 25337470. Findings 1036 patients (536 randomly allocated to carotid artery stenting, 500 to carotid endarterectomy) had baseline imaging available. Median ARWMC score was 7, and patients were dichotomised into those with a score of 7 or more and those with a score of less than 7. In patients treated with carotid artery stenting, those with an ARWMC score of 7 or more had an increased risk of stroke compared with those with a score of less than 7 (HR for any stroke 2·76, 95% CI 1·17–6·51; p=0·021; HR for non-disabling stroke 3·00, 1·10–8·36; p=0·031), but we did not see a similar association in patients treated with carotid endarterectomy (HR for any stroke 1·18, 0·40–3·55; p=0·76; HR for disabling or fatal stroke 1·41, 0·38–5·26; p=0·607). Carotid artery stenting was associated with a higher risk of stroke compared with carotid endarterectomy in patients with an ARWMC score of 7 or more (HR for any stroke 2·98, 1·29–6·93; p=0·011; HR for non

Effect of white-matter lesions on the risk of periprocedural stroke after carotid artery stenting versus endarterectomy in the International Carotid Stenting Study (ICSS): a prespecified analysis of data from a randomised trial.

PubMed

Ederle, Jörg; Davagnanam, Indran; van der Worp, H Bart; Venables, Graham S; Lyrer, Philippe A; Featherstone, Roland L; Brown, Martin M; Jäger, H Rolf

2013-09-01

Findings from randomised trials have shown a higher early risk of stroke after carotid artery stenting than after carotid endarterectomy. We assessed whether white-matter lesions affect the perioperative risk of stroke in patients treated with carotid artery stenting versus carotid endarterectomy. Patients with symptomatic carotid artery stenosis included in the International Carotid Stenting Study (ICSS) were randomly allocated to receive carotid artery stenting or carotid endarterectomy. Copies of baseline brain imaging were analysed by two investigators, who were masked to treatment, for the severity of white-matter lesions using the age-related white-matter changes (ARWMC) score. Randomisation was done with a computer-generated sequence (1:1). Patients were divided into two groups using the median ARWMC. We analysed the risk of stroke within 30 days of revascularisation using a per-protocol analysis. ICSS is registered with controlled-trials.com, number ISRCTN 25337470. 1036 patients (536 randomly allocated to carotid artery stenting, 500 to carotid endarterectomy) had baseline imaging available. Median ARWMC score was 7, and patients were dichotomised into those with a score of 7 or more and those with a score of less than 7. In patients treated with carotid artery stenting, those with an ARWMC score of 7 or more had an increased risk of stroke compared with those with a score of less than 7 (HR for any stroke 2·76, 95% CI 1·17-6·51; p=0·021; HR for non-disabling stroke 3·00, 1·10-8·36; p=0·031), but we did not see a similar association in patients treated with carotid endarterectomy (HR for any stroke 1·18, 0·40-3·55; p=0·76; HR for disabling or fatal stroke 1·41, 0·38-5·26; p=0·607). Carotid artery stenting was associated with a higher risk of stroke compared with carotid endarterectomy in patients with an ARWMC score of 7 or more (HR for any stroke 2·98, 1·29-6·93; p=0·011; HR for non-disabling stroke 6·34, 1·45-27·71; p=0·014), but

The prevalence of carotid artery stenosis in patients undergoing aortic reconstruction.

PubMed

Cahan, M A; Killewich, L A; Kolodner, L; Powell, C C; Metz, M; Sawyer, R; Lilly, M P; Benjamin, M E; Flinn, W R

1999-09-01

Coronary artery disease occurs frequently in patients undergoing aortic reconstruction, and it has been presumed that internal carotid artery occlusive disease is also common. This has led to the practice of screening for and repairing significant carotid lesions in asymptomatic patients prior to aortic reconstruction. The purpose of this study was to determine the true prevalence of internal carotid artery disease in these patients. The records of 240 patients who underwent duplex ultrasound screening for carotid artery disease prior to aortic reconstruction were reviewed. Surgery was performed for aortic aneurysm (AA) or aorto-iliac occlusive disease (AO). The prevalence of hyperlipidemia and coronary artery disease was similar between the two groups, but tobacco use, hypertension, and diabetes mellitus differed. Internal carotid artery stenosis > or = 50% occurred in 26.7% of the total group (64 of 240 cases). Stenosis > or = 50% was more common in the AO group (40 of 101 cases, 39.6%) than the AA group (24 of 139 cases, 17.3%, P = 0.0001). Severe disease (70% to 99%) was also more common in the AO group than the AA group (9.9% versus 3.6%, P = 0.0464). Internal carotid artery disease occurs commonly in patients undergoing aortic reconstruction, and screening is worthwhile. Significant disease is more common in patients with aorto-iliac occlusive disease than in those with aortic aneurysm, although atherosclerotic risk factors occur with varying frequency in the two groups. These findings suggest that additional factors may contribute to the higher prevalence of internal carotid artery stenosis in aorto-iliac occlusive disease.

Biological Antioxidant Potential Negatively Correlates With Carotid Artery Intima-Media Thickness.

PubMed

Yagi, Hideki; Sumino, Hiroyuki; Yoshida, Kensuke; Aoki, Tomoyuki; Tsunekawa, Katsuhiko; Araki, Osamu; Kimura, Takao; Nara, Makoto; Nakajima, Katsuyuki; Murakami, Masami

2016-01-01

Oxidative stress is a crucial factor in the pathogenesis and development of cardiovascular disease. Recently, simplified methods for the detection of reactive oxygen species (ROS) using the derivatives of reactive oxygen metabolites (d-ROMs) test as an index of ROS products and the biological antioxidant potential (BAP) test as an index of antioxidant potential have been utilized. These methods are easy to perform, quick, inexpensive since they use small equipment, and provide reliable results compared with established oxidative stress and antioxidant markers. Because oxidative stress has been shown to represent the balance of production of ROS and antioxidant capacity, it is more appropriate to evaluate ROS and antioxidant capacity simultaneously. However, no study has examined the associations among d-ROMs, BAP values, and carotid artery intima-media thickness (IMT) concurrently. Therefore, we studied the associations among d-ROMs, BAP values, and the carotid artery IMT. Carotid artery IMT, blood pressure (BP), fasting circulating d-ROMs, BAP, glucose metabolism, lipid, and C-reactive protein levels were measured in 95 subjects (age: 49.5 ± 13.8 years; men: 41; women: 54), including 42 healthy subjects and 53 patients with hypertension, dyslipidemia, and diabetes mellitus who were not on medication. The results of multiple regression analysis revealed that dependent carotid artery IMT determinants remained significantly associated with age, systolic BP, total cholesterol, and BAP, whereas dependent BAP determinants remained significantly associated with body mass index and carotid artery IMT. BAP was strongly correlated with carotid artery IMT in our cohort. Our results suggest that BAP may be a useful risk marker for carotid atherosclerosis.

Current understanding of chronic total occlusion of the internal carotid artery

PubMed Central

Xu, Baofeng; Li, Chao; Guo, Yunbao; Xu, Kan; Yang, Yi; Yu, Jinlu

2018-01-01

At present, there is limited understanding of chronic total occlusion (CTO) of the internal carotid artery (ICA). Therefore, the present report collected related cases from PubMed and reviewed the literature. Cerebral vessels may form collateral circulation immediately or gradually following CTO of the ICA. The natural history of CTO of the ICA includes a variety of outcomes, all of which are biased toward a non-benign progressive process and are characterized by insufficient cerebral perfusion, embolus detachment and cognitive dysfunction. The majority of cases of CTO of the ICA require treatment. In early studies, the results of external-ICA bypass were unsatisfactory, while recanalization is now considered the only viable option. The current treatment indications mainly depend on the degree of injury to the cerebrovascular reserve and the extent to which the oxygen extraction fraction is increased. The length, height and duration of ICA occlusion are also relevant, though more frequently, the condition depends on multiple factors. Endovascular interventional recanalization, carotid endarterectomy (CEA) and hybrid surgery may be conducted in a select group of patients. As novel materials are developed, the success rate of simple recanalization may gradually increase; however, hybrid surgery may be more representative of the current trend, as advanced CEA can remove carotid atherosclerosis plaques, thus reducing the technological demands of the subsequent interventional recanalization. There are many complications that may result from recanalization following CTO of the ICA, including hyperperfusion and technical errors; therefore, the operation must be conducted carefully. If the recanalization is successful, it typically results in a stable improvement of patient condition in the long term. However, despite these conclusions, more studies are required in the future to further improve current understanding of CTO of the ICA. PMID:29435269

The usefulness of carotid sinus massage in different patient groups.

PubMed

Kumar, Narasimhan Pradeep; Thomas, Alan; Mudd, Paul; Morris, Robert O; Masud, Tahir

2003-11-01

to determine the positive yield of carotid sinus massage in different patient groups: unexplained syncope, falls, dizziness and controls. observational study. teaching hospital. we studied consecutive patients over the age of 60 years referred to the 'falls clinic' with a history of unexplained syncope, unexplained falls and unexplained dizziness. We also studied asymptomatic control subjects recruited from a general practice register aged 60 years and over. All patients and control subjects underwent a full clinical assessment (comprehensive history and detailed clinical examination including supine and erect blood pressure measurements) and 12-lead electrocardiography. We performed carotid sinus massage in the supine position for 5 seconds separately on both sides followed by repeating the procedure in the upright positions using a motorised tilt table. Heart rate and blood pressure were recorded using a cardiac monitor and digital plethysmography respectively. The test was considered positive if carotid sinus massage produced asystole with more than a 3 second pause (cardioinhibitory type of carotid sinus syndrome), or a fall in systolic blood pressure of more than 50 mmHg in the absence of significant cardioinhibition (vasodepressor type of carotid sinus syndrome) or where there was evidence of both vasodepressor and cardio-inhibition as above (mixed type). we studied 44 asymptomatic control subjects and 221 symptomatic patients (130 with unexplained syncope, 41 with unexplained falls and 50 with unexplained dizziness). In the overall symptomatic patient group, the positive yield (any type of carotid sinus syndrome) was 17.6% (95% CI = 12.7-22.5). The positive yield in men (26.3% (95% CI = 16.4-36.2)) was twice that in women (13.1% (95% CI = 7.6-18.6)) (P = 0.014). Overall any type of carotid sinus syndrome was present in 22.3% (n = 29) of the syncope group, 17.1% (n = 7) in the unexplained fallers group and 6% (n = 3) in the dizziness group. We also found that

Optimal MR Plaque Imaging for Cervical Carotid Artery Stenosis in Predicting the Development of Microembolic Signals during Exposure of Carotid Arteries in Endarterectomy: Comparison of 4 T1-Weighted Imaging Techniques.

PubMed

Sato, Y; Ogasawara, K; Narumi, S; Sasaki, M; Saito, A; Tsushima, E; Namba, T; Kobayashi, M; Yoshida, K; Terayama, Y; Ogawa, A

2016-06-01

Preoperative identification of plaque vulnerability may allow improved risk stratification for patients considered for carotid endarterectomy. The present study aimed to determine which plaque imaging technique, cardiac-gated black-blood fast spin-echo, magnetization-prepared rapid acquisition of gradient echo, source image of 3D time-of-flight MR angiography, or noncardiac-gated spin-echo, most accurately predicts development of microembolic signals during exposure of carotid arteries in carotid endarterectomy. Eighty patients with ICA stenosis (≥70%) underwent the 4 sequences of preoperative MR plaque imaging of the affected carotid bifurcation and then carotid endarterectomy under transcranial Doppler monitoring of microembolic signals in the ipsilateral middle cerebral artery. The contrast ratio of the carotid plaque was calculated by dividing plaque signal intensity by sternocleidomastoid muscle signal intensity. Microembolic signals during exposure of carotid arteries were detected in 23 patients (29%), 3 of whom developed new neurologic deficits postoperatively. Those deficits remained at 24 hours after surgery in only 1 patient. The area under the receiver operating characteristic curve to discriminate between the presence and absence of microembolic signals during exposure of the carotid arteries was significantly greater with nongated spin-echo than with black-blood fast spin-echo (difference between areas, 0.258; P < .0001), MPRAGE (difference between areas, 0.106; P = .0023), or source image of 3D time-of-flight MR angiography (difference between areas, 0.128; P = .0010). Negative binomial regression showed that in the 23 patients with microembolic signals, the contrast ratio was associated with the number of microembolic signals only in nongated spin-echo (risk ratio, 1.36; 95% confidence interval, 1.01-1.97; P < .001). Nongated spin-echo may predict the development of microembolic signals during exposure of the carotid arteries in carotid

Cerebral misery perfusion due to carotid occlusive disease

PubMed Central

Maddula, Mohana; Sprigg, Nikola; Bath, Philip M; Munshi, Sunil

2017-01-01

Purpose Cerebral misery perfusion (CMP) is a condition where cerebral autoregulatory capacity is exhausted, and cerebral blood supply in insufficient to meet metabolic demand. We present an educational review of this important condition, which has a range of clinical manifestations. Method A non-systematic review of published literature was undertaken on CMP and major cerebral artery occlusive disease, using Pubmed and Sciencedirect. Findings Patients with CMP may present with strokes in watershed territories, collapses and transient ischaemic attacks or episodic movements associated with an orthostatic component. While positron emission tomography is the gold standard investigation for misery perfusion, advanced MRI is being increasingly used as an alternative investigation modality. The presence of CMP increases the risk of strokes. In addition to the devastating effect of stroke, there is accumulating evidence of impaired cognition and quality of life with carotid occlusive disease (COD) and misery perfusion. The evidence for revascularisation in the setting of complete carotid occlusion is weak. Medical management constitutes careful blood pressure management while addressing other vascular risk factors. Discussion The evidence for the management of patients with COD and CMP is discussed, together with recommendations based on our local experience. In this review, we focus on misery perfusion due to COD. Conclusion Patients with CMP and COD may present with a wide-ranging clinical phenotype and therefore to many specialties. Early identification of patients with misery perfusion may allow appropriate management and focus on strategies to maintain or improve cerebral blood flow, while avoiding potentially harmful treatment. PMID:28959496

Overexpression of hypoxia/inflammatory markers in atherosclerotic carotid plaques.

PubMed

Luque, Ana; Turu, Marta; Juan-Babot, Oriol; Cardona, Pere; Font, Angels; Carvajal, Ana; Slevin, Mark; Iborra, Elena; Rubio, Francisco; Badimon, Lina; Krupinski, Jerzy

2008-05-01

Hypoxia, angiogenesis and inflammation leads to plaque progression and remodelling and may significantly contribute towards plaque rupture and subsequent cerebrovascular events. Our aim was to study, markers of hypoxia and inflammation previously identified by microarray analysis, in atherosclerotic carotid arteries with low to moderate stenosis. We hoped to describe different cellular populations expressing the studied markers. The location of selected inflammatory molecules obtained as vascular transplants from organ donors were analysed by immunohistochemistry with monoclonal and polyclonal antibodies. Paraffin-embedded sections were cut and probed with antibodies recognizing active B and T-lymphocytes (CD30), hypoxia-inducible factor-1alpha, endoglin (CD105), Interleukin-6 and C-reactive protein. We observed a notable overexpression of HIF-1alpha in inflammatory and hypoxic areas of carotid arteries in all types of lesions from type II-V taken from the patients with carotid stenosis less than 50%. This suggests that HIF-1alpha may have a putative role in atherosclerosis progression and angiogenesis. Dynamic changes in the non-occluding plaques may explain some of the clinical events in patients with low to moderate carotid stenosis.

Impact of Hypertriglyceridemia on Carotid Stenosis Progression under Normal Low-Density Lipoprotein Cholesterol Levels.

PubMed

Kitagami, Masayuki; Yasuda, Ryuta; Toma, Naoki; Shiba, Masato; Nampei, Mai; Yamamoto, Yoko; Nakatsuka, Yoshinari; Sakaida, Hiroshi; Suzuki, Hidenori

2017-08-01

Dyslipidemia is a well-known risk factor for carotid stenosis progression, but triglycerides have attracted little attention. The aim of this study was to assess if serum triglycerides affect progression of carotid stenosis in patients with well-controlled low-density lipoprotein cholesterol (LDL-C) levels. This is a retrospective study in a single hospital consisting of 71 Japanese patients with internal carotid artery stenosis greater than or equal to 50% and normal serum LDL-C levels who underwent angiographic examination with or without the resultant carotid artery stenting or endarterectomy from 2007 to 2011, and were subsequently followed up for 4 years. Clinical factors including fasting serum triglyceride values were compared between the progression (≥10% increase in degree of carotid stenosis on ultrasonography) and the nonprogression groups. During 4 years, 15 patients (21.1%) had carotid stenosis progression on either side. Cox regression analysis demonstrated that symptomatic cases (hazard ratio [HR], 4.327; P = .019), coexisting intracranial arteriosclerotic stenosis (HR, 5.341; P = .005), and hypertriglyceridemia (HR, 6.228; P = .011) were associated with subsequent progression of carotid stenosis. Kaplan-Meier plots demonstrated that the progression-free survival rate was significantly higher in patients without hypertriglyceridemia and intracranial arteriosclerotic stenosis at baseline. Among patients with moderate to severe carotid stenosis and well-controlled LDL-C, hypertriglyceridemia was an important risk factor for progression of carotid stenosis irrespective of surgical treatments. It would be worthwhile to test if triglyceride-lowering medications suppress carotid stenosis progression. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Carotid intima-media thickness: ultrasound measurement, prognostic value and role in clinical practice.

PubMed

Nair, Satheesh Balakrishnan; Malik, Rayaz; Khattar, Rajdeep S

2012-12-01

Ultrasound measurement of carotid intima-media thickness (IMT) has become a valuable tool for detecting and monitoring progression of atherosclerosis and recently published recommendations provide guidance for proper standardisation of these measurements. Important determinants of carotid IMT include age, gender, systolic blood pressure, diabetes mellitus and serum cholesterol levels. Many studies have shown carotid IMT to correlate with the severity of coronary atherosclerosis assessed by CT coronary calcification scores, coronary angiography and intravascular ultrasound. Consistent with its correlation with cardiovascular risk factors and coronary artery disease, a meta-analysis of large observational studies has shown carotid IMT to be a strong predictor of future cardiovascular events. Moreover, in patients with established coronary artery disease a reduction in carotid IMT has been shown to translate into a reduction in future cardiovascular events. Consensus statements now also recommend carotid IMT measurements to further refine the prognostic assessment of patients traditionally considered to be at an intermediate risk of cardiovascular disease.

Anatomical characteristics of the styloid process in internal carotid artery dissection: Case-control study.

PubMed

Amorim, José M; Pereira, Daniela; Rodrigues, Marta G; Beato-Coelho, José; Lopes, Margarida; Cunha, André; Figueiredo, Sofia; Mendes-Pinto, Mafalda; Ferreira, Carla; Sargento-Freitas, João; Castro, Sérgio; Pinho, João

2018-06-01

Introduction Pathophysiology of cervical artery dissection is complex and poorly understood. In addition to well-known causative and predisposing factors, including major trauma and monogenic connective tissue disorders, morphological characteristics of the styloid process have been recently recognized as a possible risk factor for cervical internal carotid artery dissection. Aims To study the association of the anatomical characteristics of styloid process with internal carotid artery dissection. Methods Retrospective, multicenter, case-control study of patients with internal carotid artery dissection and age- and sex-matched controls. Consecutive patients with internal carotid artery dissection and controls with ischemic stroke or transient ischemic attack of any etiology excluding internal carotid artery dissection, who had performed computed tomography angiography, diagnosed between January 2010 and September 2016. Two independent observers measured styloid process length and styloid process distance to internal carotid artery. Results Sixty-two patients with internal carotid artery dissection and 70 controls were included. Interobserver agreement was good for styloid process length and styloid process-internal carotid artery distance (interclass correlation coefficient = 0.89 and 0.76, respectively). Styloid process ipsilateral to dissection was longer than left and right styloid process in controls (35.8 ± 14.4 mm versus 30.4 ± 8.9 mm and 30.3 ± 8.2 mm, p = 0.011 and p = 0.008, respectively). Styloid process-internal carotid artery distance ipsilateral to dissection was shorter than left and right distance in controls (6.3 ± 1.9 mm versus 7.2 ± 2.1 mm and 7.0 ± 2.3 mm, p = 0.003 and p = 0.026, respectively). Internal carotid artery dissection was associated with styloid process length (odds ratio = 1.04 mm -1 , 95% confidence interval = 1.01-1.08, p = 0.015) and styloid process

Aortic Baroreceptors Display Higher Mechanosensitivity than Carotid Baroreceptors.

PubMed

Lau, Eva On-Chai; Lo, Chun-Yin; Yao, Yifei; Mak, Arthur Fuk-Tat; Jiang, Liwen; Huang, Yu; Yao, Xiaoqiang

2016-01-01

Arterial baroreceptors are mechanical sensors that detect blood pressure changes. It has long been suggested that the two arterial baroreceptors, aortic and carotid baroreceptors, have different pressure sensitivities. However, there is no consensus as to which of the arterial baroreceptors are more sensitive to changes in blood pressure. In the present study, we employed independent methods to compare the pressure sensitivity of the two arterial baroreceptors. Firstly, pressure-activated action potential firing was measured by whole-cell current clamp with a high-speed pressure clamp system in primary cultured baroreceptor neurons. The results show that aortic depressor neurons possessed a higher percentage of mechano-sensitive neurons. Furthermore, aortic baroreceptor neurons show a lower pressure threshold than that of carotid baroreceptor neurons. Secondly, uniaxial stretching of baroreceptor neurons, that mimics the forces exerted on blood vessels, elicited a larger increase in intracellular Ca(2+) rise in aortic baroreceptor neurons than in carotid baroreceptor neurons. Thirdly, the pressure-induced action potential firing in the aortic depressor nerve recorded in vivo was also higher. The present study therefore provides for a basic physiological understanding on the pressure sensitivity of the two baroreceptor neurons and suggests that aortic baroreceptors have a higher pressure sensitivity than carotid baroreceptors.

Quantification of carotid atherosclerotic plaque components using feature space analysis and magnetic resonance imaging.

PubMed

Karmonik, Christof; Basto, Pamela; Morrisett, Joel D

2006-01-01

Atherosclerosis is one of the main causes of cardiovascular disease, accounting for more than one third of all deaths in the United States, there is a growing need to develop non-invasive techniques to assess the severity of atherosclerotic plaque burden. Recent research has suggested that not the size of the atherosclerotic plaque but rather its composition is indicative for plaque rupture as the underlying event of stroke and acute coronary syndrome. With its excellent soft-tissue contrast, magnetic resonance imaging (MRI) is a favored modality for examining plaque composition. In an ex-vivo study, aimed to show the feasibility of quantifying the components of carotid atherosclerotic plaques in-vivo, we acquired multi-contrast MRI images of 13 freshly excised endarterectomy tissues with commercially available MRI sequences and a human surface coil. Feature space analysis (FSA) was utilized in four representative tissues to determine the total relative abundance of calcific, lipidic, fibrotic, thrombotic and normal components as well as in consecutive 2 mm sections across the carotid bifurcation in each tissue. Excellent qualitative agreement between the FSA results and the results obtained from histological methods was observed. This study demonstrates the feasibility of combining MRI with FSA to quantify carotid atherosclerotic plaques in-vivo.

Carotid Artery Ultrasonographic Assessment in Patients from the Fremantle Diabetes Study Phase II with Carotid Bruits Detected by Electronic Auscultation

PubMed Central

Knapp, Arthur; Cetrullo, Violetta; Sillars, Brett A.; Lenzo, Nat; Davis, Wendy A.

2014-01-01

Abstract Background: Electronic auscultation appears superior to acoustic auscultation for identifying hemodynamic abnormalities. The aim of this study was to determine whether carotid bruits detected by electronic stethoscope in patients with diabetes are associated with stenoses and increased carotid intima-medial thickness (CIMT). Subjects and Methods: Fifty Fremantle Diabetes Study patients (mean±SD age, 73.7±10.0 years; 38.0% males) with a bruit found by electronic auscultation and 50 age- and sex-matched patients with normal carotid sounds were studied. The degree of stenosis and CIMT were assessed from duplex ultrasonography. Results: Patients with a bruit were more likely to have stenosis of ≥50% and CIMT of >1.0 mm than those without (odds ratios [95% confidence intervals]=14.0 [1.8–106.5] and 5.3 [1.8–15.3], respectively; both P=0.001). For the six patients with stenosis of ≥70%, five had a bruit, and one (with a known total occlusion) did not (odds ratio=5.0 [0.6–42.8]; P=0.22). The sensitivity and specificity of carotid bruit for stenoses of ≥50% were 88% and 58%, respectively; respective values for stenoses of ≥70% were 83% and 52%. The equivalent negative predictive values were 96% and 98%, and positive predictive values were 30% and 10%, respectively. Conclusions: Electronic recording of carotid sounds for later interpretation is convenient and reliable. Most patients with stenoses had an overlying bruit. Most bruits were false positives, but ultrasonography is justified to document extent of disease; CIMT measurement will identify increased vascular risk in most of these patients. The absence of a bruit was rarely a false-negative finding, suggesting that these patients can usually be reassured that they do not have hemodynamically important stenosis. PMID:24988112

Carotid artery ultrasonographic assessment in patients from the Fremantle Diabetes Study Phase II with carotid bruits detected by electronic auscultation.

PubMed

Knapp, Arthur; Cetrullo, Violetta; Sillars, Brett A; Lenzo, Nat; Davis, Wendy A; Davis, Timothy M E

2014-09-01

Electronic auscultation appears superior to acoustic auscultation for identifying hemodynamic abnormalities. The aim of this study was to determine whether carotid bruits detected by electronic stethoscope in patients with diabetes are associated with stenoses and increased carotid intima-medial thickness (CIMT). Fifty Fremantle Diabetes Study patients (mean±SD age, 73.7±10.0 years; 38.0% males) with a bruit found by electronic auscultation and 50 age- and sex-matched patients with normal carotid sounds were studied. The degree of stenosis and CIMT were assessed from duplex ultrasonography. Patients with a bruit were more likely to have stenosis of ≥50% and CIMT of >1.0 mm than those without (odds ratios [95% confidence intervals]=14.0 [1.8-106.5] and 5.3 [1.8-15.3], respectively; both P=0.001). For the six patients with stenosis of ≥70%, five had a bruit, and one (with a known total occlusion) did not (odds ratio=5.0 [0.6-42.8]; P=0.22). The sensitivity and specificity of carotid bruit for stenoses of ≥50% were 88% and 58%, respectively; respective values for stenoses of ≥70% were 83% and 52%. The equivalent negative predictive values were 96% and 98%, and positive predictive values were 30% and 10%, respectively. Electronic recording of carotid sounds for later interpretation is convenient and reliable. Most patients with stenoses had an overlying bruit. Most bruits were false positives, but ultrasonography is justified to document extent of disease; CIMT measurement will identify increased vascular risk in most of these patients. The absence of a bruit was rarely a false-negative finding, suggesting that these patients can usually be reassured that they do not have hemodynamically important stenosis.

An Hybrid 2-Stage Technique to Treat a Post-Traumatic Internal Carotid-Jugular Fistula.

PubMed

Massara, Mafalda; Barillà, David; De Caridi, Giovanni; Serra, Raffaele; Volpe, Alberto; Cutrupi, Andrea; Alberti, Antonino; Volpe, Pietro

2017-01-01

Penetrating wounds of the neck involving the carotid arteries can lead to 2 possible and important late sequelae: pseudoaneurysm formation and arteriovenous fistula (AVF), if an artery and the adjacent jugular vein are simultaneously lacerated. Traumatic AVF of the neck are rare complications and if untreated may cause congestive heart failure, cerebral ischemia, thromboembolism, or even rupture complications. Current treatment options for carotid-jugular AVF include operative repair, detachable balloon, coiling, or stenting. We present a hybrid 2-stage technique to treat an internal carotid-jugular vein fistula in a young woman, based first on carotid stenting to reduce the bleeding and reestablish an adequate cerebral perfusion, followed by stent removal and safe vessels surgical reconstruction through carotid-to-carotid bypass and vein repair. Copyright © 2016 Elsevier Inc. All rights reserved.

MRI-based biomechanical parameters for carotid artery plaque vulnerability assessment.

PubMed

Speelman, Lambert; Teng, Zhongzhao; Nederveen, Aart J; van der Lugt, Aad; Gillard, Jonathan H

2016-03-01

Carotid atherosclerotic plaques are a major cause of ischaemic stroke. The biomechanical environment to which the arterial wall and plaque is subjected to plays an important role in the initiation, progression and rupture of carotid plaques. MRI is frequently used to characterize the morphology of a carotid plaque, but new developments in MRI enable more functional assessment of carotid plaques. In this review, MRI based biomechanical parameters are evaluated on their current status, clinical applicability, and future developments. Blood flow related biomechanical parameters, including endothelial wall shear stress and oscillatory shear index, have been shown to be related to plaque formation. Deriving these parameters directly from MRI flow measurements is feasible and has great potential for future carotid plaque development prediction. Blood pressure induced stresses in a plaque may exceed the tissue strength, potentially leading to plaque rupture. Multi-contrast MRI based stress calculations in combination with tissue strength assessment based on MRI inflammation imaging may provide a plaque stress-strength balance that can be used to assess the plaque rupture risk potential. Direct plaque strain analysis based on dynamic MRI is already able to identify local plaque displacement during the cardiac cycle. However, clinical evidence linking MRI strain to plaque vulnerability is still lacking. MRI based biomechanical parameters may lead to improved assessment of carotid plaque development and rupture risk. However, better MRI systems and faster sequences are required to improve the spatial and temporal resolution, as well as increase the image contrast and signal-to-noise ratio.

Extensive Mobile Thrombus of the Internal Carotid Discovered After Intravenous Thrombolysis

PubMed Central

Fugate, Jennifer E.; Hocker, Sara E.

2016-01-01

This case report describes a rare presentation of ischemic stroke secondary to an extensive internal carotid artery thrombus, subsequent therapeutic dilemma, and clinical management. A 58-year-old man was administered intravenous (IV) thrombolysis for right middle cerebral artery territory ischemic stroke symptoms. A computed tomography angiogram of the head and neck following thrombolysis showed a longitudinally extensive internal carotid artery thrombus originating at the region of high-grade calcific stenosis. Mechanical embolectomy was deferred because of risk of clot dislodgement and mild neurological symptoms. Recumbency and hemodynamic augmentation were used acutely to support cerebral perfusion. Anticoagulation was started 24 hours after thrombolysis. Carotid endarterectomy was completed successfully within 1 week of presentation. Clinical outcome was satisfactory with discharge modified Rankin Scale score 0. A longitudinally extensive carotid artery thrombus poses a risk of dislodgement and hemispheric stroke. Optimal management in these cases is not known with certainty. In our case, IV thrombolysis, hemodynamic augmentation, delayed anticoagulation, and carotid endarterectomy resulted in a favorable clinical outcome. PMID:28400904

Modified Eversion Carotid Endarterectomy (mECEA): Analysis of Clinical and Financial Outcomes.

PubMed

Musicant, Scott E; Guzzetta, Vincent J; Terramani, Thomas T; Greenwood, Kristina L; Chiodo, Wendy C; Heaney, Karen M; Berthiaume, Shelley J

2017-07-01

Several carotid endarterectomy techniques have been described, including conventional carotid endarterectomy (CCEA) performed with patch repair and eversion carotid endarterectomy (ECEA) performed with transection of the internal carotid artery. We describe our simplified technique of modified eversion carotid endarterectomy (mECEA) with longitudinal arteriotomy limited to the carotid bulb, without transection of the internal carotid artery and present our analysis of its safety, efficacy, and cost effectiveness. A retrospective review of all carotid endarterectomies performed by 3 vascular surgeons over a 3-year period was completed. About 197 mECEA were performed during the study period. Follow-up data were obtained on 77.7% of patients. A comparison was made with the contemporary literature with respect to outcomes for both CCEA and ECEA. Between January 2012 and December 2014, a total of 197 mECEA were performed. The perioperative stroke and death rates for those undergoing mECEA was 0.5% and 0.5%, respectively. Late stroke and death rates were 3.0% and 5.1%, respectively. Perioperative rate of myocardial infarction was 1.0%. Early restenosis rates of >70% occurred in 1.4%, whereas late restenosis of >70% occurred in 2.7%. Mean operating time for those undergoing mECEA was 57.9 min. Average costs savings for mECEA compared to CCEA were $5,835. This simplified technique has comparable outcomes to those described in the contemporary literature for both CCEA and ECEA with respect to postoperative neurologic events as well as restenosis rates. In our institution, the short mean operative times with mECEA has led to reduced resource utilization. Copyright © 2017 Elsevier Inc. All rights reserved.

DNS of flow in stenosed carotid artery

NASA Astrophysics Data System (ADS)

Grinberg, Leopold; Yakhot, Alexander; Karniadakis, George

2006-11-01

Direct numerical simulation (DNS) of a three-dimensional flow through a stenosed carotid artery has been performed. Onset of turbulence downstream of the occlusion has been observed. The developing turbulence is characterized by an alternating spatio-temporal transitional regime. The transition to turbulence occurs during the systolic phase approximately five throat-diameters downstream of the throat, while laminarization occurs during the diastolic phase. Transition in space is first enhanced and subsequently decays downstream. The wall shear stress increases in the stenosed internal carotid artery due to the vessel occlusion and as the result of turbulence.

Predictors of Perioperative Stroke/Death after Carotid Artery Stenting: A Review Article

PubMed Central

AbuRahma, Ali F.

2018-01-01

Carotid artery stenting (CAS) has been recommended as an alternative treatment to carotid endarterectomy for patients with significant carotid stenosis. Only a few studies have analyzed clinical/anatomical and technical variables that affect perioperative outcomes of CAS. Following a comprehensive Medline search, it was reported that clinical factors, including age of >80 years, chronic renal failure, diabetes mellitus, symptomatic indications, and procedures performed within 2 weeks of transient ischemic attack symptoms, are associated with high perioperative stroke and death rates. They also highlighted that angiographic variables, e.g., ulcerated and calcified plaques, left carotid intervention, >90% stenosis, >10-mm target lesion length, ostial involvement, type III aortic arch, and >60°-angulated internal carotid and common carotid arteries, are predictors of increased stroke rates. Technical factors associated with increased perioperative risk of stroke include percutaneous transluminal angioplasty (PTA) without embolic protection devices, PTA before stent placement, and the use of multiple stents. This review describes the most widely quoted data in defining various predictors of perioperative stroke and death after CAS. (This is a review article based on the invited lecture of the 45th Annual Meeting of Japanese Society for Vascular Surgery.) PMID:29682104

Will mesh-covered stents help reduce stroke associated with carotid stent angioplasty?

PubMed

Richards, Carly N; Schneider, Peter A

2017-03-01

Carotid stent angioplasty (CAS) has been shown to protect patient from future stroke long-term efficacy similar to carotid endarterectomy (CEA). The risk of minor stroke in the perioperative period is higher than with CEA and not related to cerebral protection during the CAS procedure since a significant portion of the neurologic events occur between 1 and 30 days following stent deployment. This observation suggests mechanisms integral to the stent itself may be pertinent such as plaque embolization thru the stent struts may occur. It appears that this embolic risk can be reduced by use of specific carotid stent designs that include a mesh covering to minimize the open struts areas and thus embolization through the carotid stent. Improvements in stent design that eliminate post-procedural debris embolization will expand the application of CAS for severe internal carotid artery atherosclerotic stenosis. Copyright © 2017. Published by Elsevier Inc.

Intraoperative Hypoglossal Nerve Mapping During Carotid Endarterectomy: Technical Note.

PubMed

Kojima, Atsuhiro; Saga, Isako; Ishikawa, Mami

2018-05-01

Hypoglossal nerve deficit is a possible complication caused by carotid endarterectomy (CEA). The accidental injury of the hypoglossal nerve during surgery is one of the major reasons for permanent hypoglossal nerve palsy. In this study, we investigated the usefulness of intraoperative mapping of the hypoglossal nerve to identify this nerve during CEA. Five consecutive patients who underwent CEA for the treatment of symptomatic or asymptomatic carotid artery stenosis were studied. A hand-held probe was used to detect the hypoglossal nerve in the operative field, and the tongue motor evoked potentials (MEPs) were recorded. The tongue MEPs were obtained in all the patients. The invisible hypoglossal nerve was successfully identified without any difficulty when the internal carotid artery was exposed. Intraoperative mapping was particularly useful for identifying the hypoglossal nerve when the hypoglossal nerve passed beneath the posterior belly of the digastric muscle. In 1 of 2 cases, MEP was also elicited when the ansa cervicalis was stimulated, although the resulting amplitude was much smaller than that obtained by direct stimulation of the hypoglossal nerve. Postoperatively, none of the patients presented with hypoglossal nerve palsy. Intraoperative hypoglossal nerve mapping enabled us to locate the invisible hypoglossal nerve during the exposure of the internal carotid artery accurately without retracting the posterior belly of the digastric muscle and other tissues in the vicinity of the internal carotid artery. Copyright © 2018 Elsevier Inc. All rights reserved.

Outcome of Carotid Artery Stenting for Radiation-Induced Stenosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dorresteijn, Lucille, E-mail: L.Dorresteijn@mst.n; Vogels, Oscar; Leeuw, Frank-Erik de

2010-08-01

Purpose: Patients who have been irradiated at the neck have an increased risk of symptomatic stenosis of the carotid artery during follow-up. Carotid angioplasty and stenting (CAS) can be a preferable alternative treatment to carotid endarterectomy, which is associated with increased operative risks in these patients. Methods and Materials: We performed a prospective cohort study of 24 previously irradiated patients who underwent CAS for symptomatic carotid stenosis. We assessed periprocedural and nonprocedural events including transient ischemic attack (TIA), nondisabling stroke, disabling stoke, and death. Patency rates were evaluated on duplex ultrasound scans. Restenosis was defined as a stenosis of >50%more » at the stent location. Results: Periprocedural TIA rate was 8%, and periprocedural stroke (nondisabling) occurred in 4% of patients. After a mean follow-up of 3.3 years (range, 0.3-11.0 years), only one ipsilateral incident event (TIA) had occurred (4%). In 12% of patients, a contralateral incident event was present: one TIA (4%) and two strokes (12%, two disabling strokes). Restenosis was apparent in 17%, 33%, and 42% at 3, 12, and 24 months, respectively, although none of the patients with restenosed vessels became symptomatic. The length of the irradiation to CAS interval proved the only significant risk factor for restenosis. Conclusions: The results of CAS for radiation-induced carotid stenosis are favorable in terms of recurrence of cerebrovascular events at the CAS site.« less

Advanced Solid State Lighting for Human Evaluation Project

NASA Technical Reports Server (NTRS)

Zeitlin, Nancy; Holbert, Eirik

2015-01-01

Lighting intensity and color have a significant impact on human circadian rhythms. Advanced solid state lighting was developed for the Advanced Exploration System (AES) Deep Space Habitat(DSH) concept demonstrator. The latest generation of assemblies using the latest commercially available LED lights were designed for use in the Bigelow Aerospace Environmental Control and Life Support System (ECLSS) simulator and the University of Hawaii's Hawaii Space Exploration Analog and Simulation (Hi-SEAS) habitat. Agreements with both these organizations will allow the government to receive feedback on the lights and lighting algorithms from long term human interaction.

Polymorphism rs2073618 of the osteoprotegerin gene as a potential marker of subclinical carotid atherosclerosis in Caucasians with type 2 diabetes mellitus.

PubMed

Pleskovič, Aleš; Ramuš, Sara Mankoč; Pražnikar, Zala Jenko; Šantl Letonja, Marija; Cokan Vujkovac, Andreja; Gazdikova, Katarina; Caprnda, Martin; Gaspar, Ludovit; Kruzliak, Peter; Petrovič, Daniel

2017-08-01

The OPG/RANKL/RANK (osteoprotegerin/receptor-activator of nuclear factor κB ligand/receptor-activator of nuclear factor κB) axis has been recently linked to the development of atherosclerosis and plaque destabilization. We have investigated whether polymorphism rs2073618 of the OPG gene is associated with subclinical markers of carotid atherosclerosis in subjects with type 2 diabetes mellitus (T2DM). 595 subjects with T2DM were enrolled in the cross-sectional study. Subclinical markers of carotid atherosclerosis (carotid intima media thickness, plaque thickness, and plaques presence) were assessed with ultrasound at the time of recruitment. Genotyping for rs2073618 (a missense variant located in exon I of the OPG gene) was performed, and OPG serum levels were determined by ELISA. Compared to the GG genotype, the CC genotype of the rs2073618 polymorphism had a significantly increased risk for the presence of carotid plaque (OR = 2.54, 95 % CI = 1.22-5.28, p = 0.01). No statistically significant difference could be detected (p = 0.68) upon comparing median values of serum OPG levels among studied genotype groups in subjects with T2DM. Multivariable linear regression analyses in T2DM subjects demonstrated that GC and CC genotypes (p = 0.03 and p = 0.003), together with statin therapy (p = 0.009), were independent predictors of the number of carotid segments with plaques. Despite the fact that OPG rs2073618 genotypes failed to predict the serum OPG levels as there was no statistical difference among compared genotypes, our results demonstrate that the rs2073618 polymorphism could be a possible genetic marker for the prediction of increased risk for carotid plaque burden as a measure of advanced subclinical atherosclerosis in T2DM subjects.

Learning-based automated segmentation of the carotid artery vessel wall in dual-sequence MRI using subdivision surface fitting.

PubMed

Gao, Shan; van 't Klooster, Ronald; Kitslaar, Pieter H; Coolen, Bram F; van den Berg, Alexandra M; Smits, Loek P; Shahzad, Rahil; Shamonin, Denis P; de Koning, Patrick J H; Nederveen, Aart J; van der Geest, Rob J

2017-10-01

The quantification of vessel wall morphology and plaque burden requires vessel segmentation, which is generally performed by manual delineations. The purpose of our work is to develop and evaluate a new 3D model-based approach for carotid artery wall segmentation from dual-sequence MRI. The proposed method segments the lumen and outer wall surfaces including the bifurcation region by fitting a subdivision surface constructed hierarchical-tree model to the image data. In particular, a hybrid segmentation which combines deformable model fitting with boundary classification was applied to extract the lumen surface. The 3D model ensures the correct shape and topology of the carotid artery, while the boundary classification uses combined image information of 3D TOF-MRA and 3D BB-MRI to promote accurate delineation of the lumen boundaries. The proposed algorithm was validated on 25 subjects (48 arteries) including both healthy volunteers and atherosclerotic patients with 30% to 70% carotid stenosis. For both lumen and outer wall border detection, our result shows good agreement between manually and automatically determined contours, with contour-to-contour distance less than 1 pixel as well as Dice overlap greater than 0.87 at all different carotid artery sections. The presented 3D segmentation technique has demonstrated the capability of providing vessel wall delineation for 3D carotid MRI data with high accuracy and limited user interaction. This brings benefits to large-scale patient studies for assessing the effect of pharmacological treatment of atherosclerosis by reducing image analysis time and bias between human observers. © 2017 American Association of Physicists in Medicine.

Evaluating endothelial function of the common carotid artery: an in vivo human model.

PubMed

Mazzucco, S; Bifari, F; Trombetta, M; Guidi, G C; Mazzi, M; Anzola, G P; Rizzuto, N; Bonadonna, R

2009-03-01

Flow mediated dilation (FMD) of peripheral conduit arteries is a well-established tool to evaluate endothelial function. The aims of this study are to apply the FMD model to cerebral circulation by using acetazolamide (ACZ)-induced intracranial vasodilation as a stimulus to increase common carotid artery (CCA) diameter in response to a local increase of blood flow velocity (BFV). In 15 healthy subjects, CCA end-diastolic diameter and BFV, middle cerebral artery (MCA) BFV and mean arterial blood pressure (MBP) were measured at basal conditions, after an intravenous bolus of 1g ACZ, and after placebo (saline) sublingual administration at the 15th and 20th minute. In a separate session, the same parameters were evaluated after placebo (saline) infusion instead of ACZ and after 10 microg/m(2) bs and 300 microg of glyceryl trinitrate (GTN), administered sublingually, at the 15th and 20th minute, respectively. After ACZ bolus, there was a 35% maximal MCA mean BFV increment (14th minute), together with a 22% increase of mean CCA end-diastolic BFV and a CCA diameter increment of 3.9% at the 3rd minute (p=0.024). There were no MBP significant variations up to the 15th minute (p=0.35). After GTN administration, there was a significant increment in CCA diameter (p<0.00001). ACZ causes a detectable CCA dilation in healthy individuals concomitantly with an increase in BFV. Upon demonstration that this phenomenon is endothelium dependent, this experimental model might become a valuable tool to assess endothelial function in the carotid artery.

In vivo repeatability of the pulse wave inverse problem in human carotid arteries.

PubMed

McGarry, Matthew; Nauleau, Pierre; Apostolakis, Iason; Konofagou, Elisa

2017-11-07

Accurate arterial stiffness measurement would improve diagnosis and monitoring for many diseases. Atherosclerotic plaques and aneurysms are expected to involve focal changes in vessel wall properties; therefore, a method to image the stiffness variation would be a valuable clinical tool. The pulse wave inverse problem (PWIP) fits unknown parameters from a computational model of arterial pulse wave propagation to ultrasound-based measurements of vessel wall displacements by minimizing the difference between the model and measured displacements. The PWIP has been validated in phantoms, and this study presents the first in vivo demonstration. The common carotid arteries of five healthy volunteers were imaged five times in a single session with repositioning of the probe and subject between each scan. The 1D finite difference computational model used in the PWIP spanned from the start of the transducer to the carotid bifurcation, where a resistance outlet boundary condition was applied to approximately model the downstream reflection of the pulse wave. Unknown parameters that were estimated by the PWIP included a 10-segment linear piecewise compliance distribution and 16 discrete cosine transformation coefficients for each of the inlet boundary conditions. Input data was selected to include pulse waves resulting from the primary pulse and dicrotic notch. The recovered compliance maps indicate that the compliance increases close to the bifurcation, and the variability of the average pulse wave velocity estimated through the PWIP is on the order of 11%, which is similar to that of the conventional processing technique which tracks the wavefront arrival time (13%). Copyright © 2017 Elsevier Ltd. All rights reserved.

Carotid Plaque Morphology in Asymptomatic Patients with and without Metabolic Syndrome.

PubMed

Cury, Marcus Vinícius Martins; Presti, Calógero; Bonadiman, Suellen Stevam Timotheo; Casella, Ivan Benaduce; Benabou, Joseph Elias; da Silva, Erasmo Simão; de Luccia, Nelson; Puech-Leão, Pedro

2017-02-01

The aim of this study was to determine the impact of metabolic syndrome (MetS) on the morphology of carotid plaques, as evaluated using duplex ultrasound (DUS) with computer-assisted analysis. In this cross-sectional observational study, we analyzed 148 carotid artery plaques in asymptomatic patients. Data were obtained via clinical and laboratory examinations, and DUS was performed by a single operator. All plaques were scanned in a longitudinal fashion, and the best segment was selected, recorded, and evaluated using dedicated software. The main software-based analyses included gray-scale median (GSM) measurements and carotid plaque morphology histograms. MetS was identified in 51.8% of patients. Comparisons of patients with MetS and patients without MetS indicated that the former patients used more classes of antihypertensive drugs (2.49 vs. 1.93; P = 0.004) and were treated with statins for a longer period (71.08 vs. 49.17 months; P = 0.003). Most patients of both types exhibited moderate carotid artery stenosis ranging from 50% to 69% (n = 62; 37.3%), and MetS was not associated with an increased prevalence of severe carotid artery stenosis. The mean GSM was greater in the MetS group than in the non-MetS group (74.18 vs. 61.63; P = 0.012). The histogram analysis revealed that there were lower quantities of blood and fat (2.91 vs. 3.88; P = 0.006; 10.21 vs. 15.08; P = 0.004, respectively) and more fibrous tissue (19.93 vs. 14.55; P = 0.015) in the carotid plaques of patients with MetS than in the carotid plaques of patients without MetS. The present study demonstrated that MetS did not affect the stenosis grade or did it lead to unstable carotid plaques. Copyright © 2016 Elsevier Inc. All rights reserved.

Differential effects of estradiol on carotid artery inflammation when administered early versus late after surgical menopause.

PubMed

Sophonsritsuk, Areepan; Appt, Susan E; Clarkson, Thomas B; Shively, Carol A; Espeland, Mark A; Register, Thomas C

2013-05-01

The aim of this study was to determine the effects of estrogen therapy (ET) on carotid artery inflammation when initiated early and late relative to surgical menopause. Female cynomolgus macaques consuming atherogenic diets were ovariectomized and randomized to control or oral estradiol (E2; human equivalent dose of 1 mg/d micronized E2) initiated at 1 month (early menopause, n = 24) or 54 months (late menopause, n = 40) after ovariectomy. The treatment period was 8 months. Carotid artery expression of the markers of monocyte/macrophages (CD68 and CD163), dendritic cells (CD83), natural killer cells (neural cell adhesion molecule-1), and interferon-γ was significantly lower in E2-treated animals in the early menopause group but not in the late menopause group (P < 0.05). In contrast, carotid artery transcripts for T-cell markers (CD3, CD4, CD8, and CD25), interleukin-10, type I collagen, monocyte chemoattractant protein-1, matrix metalloproteinase-9, and tumor necrosis factor-α were lower in E2-treated monkeys regardless of menopausal stage (P < 0.05). ET initiated soon after menopause inhibits macrophage accumulation in the carotid artery, an effect that is not observed when E2 is administered after several years of estrogen deficiency. No evidence for pro-inflammatory effects of late ET is observed. The results provide support for the timing hypothesis of postmenopausal ET with implications for the interpretation of outcomes in the Women's Health Initiative.

Direct carotid cavernous fistula after submucous resection of the nasal septum.

PubMed

Bizri, A R; al-Ajam, M; Zaytoun, G; al-Kutoubi, A

2000-01-01

A carotid cavernous fistula (CCF) is an abnormal arteriovenous anastomosis between the carotid artery and the cavernous sinus. Etiologies of this condition reported in the literature so far include facial trauma, rupture of an intracavernous aneurysm of the carotid artery, Ehler-Danlos syndrome and fibromuscular dysplasia of the cerebral arteries. Such fistulae were reported as complications of rhinoplasty, transsphenoidal surgery, embolization of cavernous sinus meningioma, and rhinocerebral mucormycosis. CCF may also occur spontaneously in children or as a congenital malformation. However, to our knowledge, submucous resection of the nasal septum has not been reported before to cause direct carotid-cavernous fistula. CT and angiographic findings are presented and a review of the literature for reported causes of CCF is made as well as a brief discussion of the possible pathophysiology.

Interaction of semicircular canal stimulation with carotid baroreceptor reflex control of heart rate

NASA Technical Reports Server (NTRS)

Convertino, V. A.

1998-01-01

The carotid-cardiac baroreflex contributes to the prediction of orthostatic tolerance; experimental attenuation of the reflex response leads to orthostatic hypotension in humans and animals. Anecdotal observations indicate that rotational head movements about the vertical axis of the body can also induce orthostatic bradycardia and hypotension through increased parasympathetic activity. We therefore measured the chronotropic response to carotid baroreceptor stimulation in 12 men during varying conditions of vestibulo-oculomotor stimulation to test the hypothesis that stimulation of the semicircular canals associated with head movements in the yaw plane inhibits cardioacceleration through a vagally mediated baroreflex. Carotid-cardiac baroreflex response was assessed by plotting R-R intervals (ms) at each of 8 neck pressure steps with their respective carotid distending pressures (mmHg). Calculated baroreflex gain (maximal slope of the stimulus-response relationship) was measured under 4 experimental conditions: 1) sinusoidal whole-body yaw rotation of the subject in the dark without visual fixation (combined vestibular-oculomotor stimulation); 2) yaw oscillation of the subject while tracking a small head-fixed light moving with the subject (vestibular stimulation without eye movements); 3) subject stationary while fixating on a small light oscillating in yaw at the same frequency, peak acceleration, and velocity as the chair (eye movements without vestibular stimulation); and 4) subject stationary in the dark (no eye or head motion). Head motion alone and with eye movement reduced baseline baroreflex responsiveness to the same stimulus by 30%. Inhibition of cardioacceleration during rotational head movements may have significant impact on functional performance in aerospace environments, particularly in high-performance aircraft pilots during high angular acceleration in aerial combat maneuvers or in astronauts upon return from spaceflight who already have

Non-rigid registration for fusion of carotid vascular ultrasound and MRI volumetric datasets

NASA Astrophysics Data System (ADS)

Chan, R. C.; Sokka, S.; Hinton, D.; Houser, S.; Manzke, R.; Hanekamp, A.; Reddy, V. Y.; Kaazempur-Mofrad, M. R.; Rasche, V.

2006-03-01

In carotid plaque imaging, MRI provides exquisite soft-tissue characterization, but lacks the temporal resolution for tissue strain imaging that real-time 3D ultrasound (3DUS) can provide. On the other hand, real-time 3DUS currently lacks the spatial resolution of carotid MRI. Non-rigid alignment of ultrasound and MRI data is essential for integrating complementary morphology and biomechanical information for carotid vascular assessment. We assessed non-rigid registration for fusion of 3DUS and MRI carotid data based on deformable models which are warped to maximize voxel similarity. We performed validation in vitro using isolated carotid artery imaging. These samples were subjected to soft-tissue deformations during 3DUS and were imaged in a static configuration with standard MR carotid pulse sequences. Registration of the source ultrasound sequences to the target MR volume was performed and the mean absolute distance between fiducials within the ultrasound and MR datasets was measured to determine inter-modality alignment quality. Our results indicate that registration errors on the order of 1mm are possible in vitro despite the low-resolution of current generation 3DUS transducers. Registration performance should be further improved with the use of higher frequency 3DUS prototypes and efforts are underway to test those probes for in vivo 3DUS carotid imaging.

Magnetic resonance imaging and three-dimensional ultrasound of carotid atherosclerosis: mapping regional differences.

PubMed

Krasinski, Adam; Chiu, Bernard; Fenster, Aaron; Parraga, Grace

2009-04-01

To evaluate differences in carotid atherosclerosis measured using magnetic resonance imaging (MRI) and three-dimensional ultrasound (3DUS). Ten subject volunteers underwent carotid 3DUS and MRI (multislice black blood fast spin echo, T1-weighted contrast, double inversion recovery, 0.5 mm in-plane resolution, 2 mm slice, 3.0 T) within 1 hour. 3DUS and MR images were manually segmented by two observers providing vessel wall and lumen contours for quantification of vessel wall volume (VWV) and generation of carotid thickness maps. MRI VWV (1040 +/- 210 mm(3)) and 3DUS VWV (540 +/- 110 mm(3)) were significantly different (P < 0.0001). When normalized for the estimated adventitia volume, mean MRI VWV decreased 240 +/- 50 mm(3) and was significantly different from 3DUS VWV (P < 0.001). Two-dimensional carotid maps showed qualitative evidence of regional differences in the plaque and vessel wall thickness between MR and 3DUS in all subjects. Power Doppler US confirmed that heterogeneity in the common carotid artery in all patients resulted from apparent flow disturbances, not atherosclerotic plaque. MRI and 3DUS VWV were significantly different and carotid maps showed homogeneous thickness differences and heterogeneity in specific regions of interest identified as MR flow artifacts in the common carotid artery.

Advancing Free Flight Through Human Factors: Workshop Report

DOT National Transportation Integrated Search

1995-08-01

This report describes the results of the Advancing Free Flight Through Human : Factors technical workshop held on June 20 and 21, 1995. The purpose of this : technical workshop was to begin the process of identifying and solving human : factors issue...

Huge Free-Floating Thrombus in the Internal Carotid Artery.

PubMed

Tanriverdi, Uygur; Kizilkilic, Osman; Ince, Birsen

2017-12-01

Free-floating thrombus in the carotid artery is extremely rare. A 70-year-old male patient with pre-existing Crohn's disease admitted to our clinic with recurrent transient ischemic attacks. Angiography showed a huge thrombus in internal carotid artery. He responded to anticoagulation treatment and delayed endovascular intervention. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Cerebral embolization in asymptomatic versus symptomatic patients after carotid stenting.

PubMed

Tulip, Hans H; Rosero, Eric B; Higuera, Adriana J; Ilarraza, Adriana; Valentine, R James; Timaran, Carlos H

2012-12-01

Previous studies have investigated the development of new ischemic brain lesions on diffusion-weighted magnetic resonance imaging (DW-MRI) after carotid artery stenting (CAS). The rate of ischemic brain injury after CAS for asymptomatic stenosis has not been extensively studied but is presumed to be less likely than in symptomatic patients. This study assessed the occurrence of cerebral embolization after CAS for asymptomatic vs symptomatic carotid stenosis. During an 18-month period, 40 patients undergoing CAS under filter embolic protection were prospectively evaluated. Transcranial Doppler (TCD) during CAS and preprocedural and 24-hour postprocedural DW-MRI were used to assess cerebral embolization. Univariate and nonparametric analyses were used to compare differences in cerebral embolization after CAS in asymptomatic and symptomatic patients. CAS was performed for 23 asymptomatic (58%) and 17 symptomatic (42%) carotid stenoses. The median microembolic counts detected by TCD were 285 (interquartile range [IQR], 182-376) for asymptomatic and 313 (IQR, 170-426) for symptomatic carotid stenosis (P=.6). DW-MRI was available for assessment in 20 asymptomatic and 14 symptomatic patients. New acute cerebral emboli detected with DW-MRI occurred in 10 asymptomatic (50%) and 7 symptomatic patients (50%) undergoing CAS (P=.9). The ipsilateral and total median number of DW-MRI lesions between groups were not statistically significantly different at, respectively, 1 (IQR, 0-2.5) and 1.5 (IQR, 0-3) for asymptomatic vs 0.5 (IQR, 0-2) and 0.5 (IQR, 0-3) for symptomatic carotid stenosis (P>.5). One asymptomatic patient sustained a minor stroke after CAS. No new neurologic events occurred in symptomatic patients. The 30-day stroke-death rate was 2.5% in this series. Cerebral embolization, as detected by TCD and DW-MRI, occurs with a similar frequency after CAS for asymptomatic and symptomatic carotid stenosis. Because postprocedural ischemic brain injury occurs in approximately

Evaluation of cerebral function after carotid endarterectomy.

PubMed

Uclés, P; Almárcegui, C; Lorente, S; Romero, F; Marco, M

1997-05-01

Neuroimaging methods have failed to disclose correlation between degree of cerebral atrophy and blood flow in carotid artery stenosis patients. Moreover, intellectual improvement after carotid endarterectomy does not correlate fully with neuroimaging data in such patients. We performed brain electrical activity mapping and psychological testing before and 4 weeks after operation in 28 patients with symptomatic, high-grade, carotid stenosis. Postoperatively, electroencephalographic (EEG) mean frequency and absolute theta power improved significantly (p < 0.01). Mean frequency increased >1 Hz in most areas while power decreased dramatically, mainly because of resolution of high-voltage foci in 8 patients. Differences were conspicuous in both frontal lobes irrespective of the operated side, which suggests changes in perfusion affecting the whole brain. This is a positive effect of endarterectomy. Mini-Mental test and Set Test for verbal fluency had a positive correlation with the qEEG changes. Quantitative EEG as a measure of cerebral function has disclosed discriminative improvement in the early postoperative period. Our results support the thesis of improvement subsequent to endarterectomy.

Internal Carotid Artery Web as the Cause of Recurrent Cryptogenic Ischemic Stroke.

PubMed

Antigüedad-Muñoz, Jon; de la Riva, Patricia; Arenaza Choperena, Gorka; Muñoz Lopetegi, Amaia; Andrés Marín, Naiara; Fernández-Eulate, Gorka; Moreno Valladares, Manuel; Martínez Zabaleta, Maite

2018-05-01

Carotid artery web is considered an exceptional cause of recurrent ischemic strokes in the affected arterial territory. The underlying pathology proposed for this entity is an atypical fibromuscular dysplasia. We present the case of a 43-year-old woman with no cardiovascular risk factors who had experienced 2 cryptogenic ischemic strokes in the same arterial territory within an 11-month period. Although all diagnostic tests initially yielded normal results, detailed analysis of the computed tomography angiography images revealed a carotid web; catheter angiography subsequently confirmed the diagnosis. Carotid surgery was performed, since which time the patient has remained completely asymptomatic. The histological finding of intimal hyperplasia is consistent with previously reported cases of carotid artery web. Carotid artery web is an infrequent cause of stroke, and this diagnosis requires a high level of suspicion plus a detailed analysis of vascular imaging studies. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Simplified ultrasound protocol for the exclusion of clinically significant carotid artery stenosis.

PubMed

Högberg, Dominika; Dellagrammaticas, Demosthenes; Kragsterman, Björn; Björck, Martin; Wanhainen, Anders

2016-08-01

To evaluate a simplified ultrasound protocol for the exclusion of clinically significant carotid artery stenosis for screening purposes. A total of 9,493 carotid arteries in 4,748 persons underwent carotid ultrasound examination. Most subjects were 65-year-old men attending screening for abdominal aortic aneurysm. The presence of a stenosis on B-mode and/or a mosaic pattern in post-stenotic areas on colour Doppler and maximum peak systolic velocity (PSV) in the internal carotid artery (ICA) were recorded. A carotid stenosis was defined as The North American Symptomatic Carotid Endarterectomy Trial (NASCET) >20% and a significant stenosis as NASCET >50%. The kappa (κ) statistic was used to assess agreement between methods. Sensitivity, specificity, positive predictive (PPV), and negative predictive (NPV) values were calculated for the greyscale/mosaic method compared to conventional assessment by means of PSV measurement. An ICA stenosis was found in 121 (1.3%) arteries; 82 (0.9%) were graded 20%-49%, 16 (0.2%) were 50%-69%, and 23 (0.2%) were 70%-99%. Eighteen (0.2%) arteries were occluded. Overall, the greyscale/mosaic protocol showed a moderate agreement with ICA PSV measurements for the detection of carotid artery stenosis, κ = 0.455. The sensitivity, specificity, PPV, and NPV for detection of >20% ICA stenosis were 91% (95% CI 0.84-0.95), 97% (0.97-0.98), 31% (0.26-0.36), and 97% (0.97-0.97), respectively. The corresponding figures for >50% stenosis were 90% (0.83-0.95), 97% (0.97-0.98), 11% (0.08-0.15), and 100% (0.99-1.00). Compared with PSV measurements, the simplified greyscale/mosaic protocol had a high negative predictive value for detection of >50% carotid stenosis, suggesting that it may be suitable as a screening method to exclude significant disease.

Urinary Sodium and Potassium Excretion and Carotid Atherosclerosis in Chinese Men and Women

PubMed Central

Dai, Xiao-Wei; Wang, Cheng; Xu, Ying; Guan, Ke; Su, Yi-Xiang; Chen, Yu-Ming

2016-01-01

Limited studies have examined the association between sodium (Na) and potassium (K) levels and the risk of atherosclerosis. This study examined whether higher Na and Na/K levels and low K levels were independent risk factors for atherosclerosis. This community-based cross-sectional study included 3290 subjects (1067 men and 2223 women) 40 to 75 years of age in Guangzhou, China, between 2011 and 2013. Urinary excretion of Na and K were measured from the first morning void, and creatinine-adjusted values were used. The intima-media thickness (IMT) of the carotid common artery and the carotid bifurcation was measured with high-resolution B-mode ultrasonography. Dietary K and Na intake and other covariates were obtained by face-to-face interviews. A significant positive association was seen between urinary Na excretion and carotid atherosclerosis after adjustment for age, sex, and other lifestyle covariates. The odds ratios (OR) and 95% confidence interval (CI) of the highest (vs. lowest) quartile of urinary Na were 1.32 (1.04–1.66) for carotid plaques, 1.48 (1.18–1.87) for increased common carotid artery IMT, and 1.55 (1.23–1.96) for increased carotid bifurcation IMT (all p-trend < 0.01). A similar positive association was observed between urinary Na/K levels and carotid plaque and increased IMT, and between dietary Na intake and increased bifurcation IMT. Regarding potassium data, we only found a significantly lower presence of carotid plaque (OR 0.72, 95% CI 0.57–0.91) for quartile 2 (vs. 1) of urinary K. Our findings suggest that higher levels of urinary excretion Na and Na/K are significantly associated with greater presence of carotid atherosclerosis in Chinese adults. PMID:27706075

Dose optimization of contrast-enhanced carotid MR angiography.

PubMed

Unterweger, M; Froehlich, J M; Kubik-Huch, R A; Seifert, B; Birrer, M; Huber, T; Otto, R

2005-09-01

The purpose of this work was to compare the diagnostic performance of a single-contrast or a double-contrast dose of carotid contrast-enhanced MR angiography (MRA). One-hundred nineteen patients (mean age 65+/-14.4 years) underwent carotid contrast-enhanced MRA with a standardized protocol (repetition time/echo 3.73 ms/1.38 ms, flip-angle 25 degrees, acquisition-time 19 s, voxel size 1.2 x 1.2 x 0.9 mm3) on a 1.5-T scanner (Sonata, Siemens-Medical-Systems) using a neck phased-array coil. Contrast agent was administered intravenously at a rate of 3.0 ml/s, either as a single dose (n=57; 0.1 mmol/kg body weight) or as a double dose (n=62; 0.2 mmol/kg body weight) of meglumine gadoterate (0.5 M/l), followed by 30 ml saline. Qualitative image analysis was performed on maximum intensity projections using a five-point scale. Signal intensities were measured at three different vascular levels on both sides to assess the contrast-to-noise ratios (CNRs). Image quality was rated as good or excellent in all cases. A double dose did not influence the efficacy of carotid enhancement (CNR single dose 69.12+/-19.8; CNR double dose 70.01+/-20.7; p = 0.81) compared with a single dose. In both dose groups the mean CNRs were inversely related to bodyweight, despite adjusted contrast volumes (p=0.0005). Double-dose contrast-enhanced carotid MRA is not superior to single-dose MRA, as overall diagnostic performance and quantitative contrast enhancement are equal. Being more cost-efficient, a single-dose administration of contrast agent is recommended for MRA of the carotid arteries.

Blood flow changes after unilateral carotid artery ligation monitored by optical coherence tomography

NASA Astrophysics Data System (ADS)

Ma, Yushu; Liang, Chengbo; Suo, Yanyan; Zhao, Yuqian; Wang, Yi; Xu, Tao; Wang, Ruikang; Ma, Zhenhe

2016-03-01

Unilateral carotid artery ligation which could induce adaptive improvement is a classic model that has been widely used to study pathology of ischemic disease. In those studies, blood flow is an important parameter to characterize the ischemia. Optical coherence tomography (OCT) is a powerful imaging modality which can provide depth resolved images in biological tissue with high spatial and temporal resolution. SPF rats was anesthetized with isoflurane and divided into two groups. In first group, bilateral carotid artery was surgically exposed, and then left carotid artery was ligated. Blood flow changes of the contralateral carotid artery was monitored using high speed spectral domain optical coherence tomography, including the absolute flow velocity and the flow volume. In the other group, skull window was opened at the ipsilateral cerebral cortex of ligation and blood supply of small artery was measured before and after the ligation. The measured results demonstrate the blood supply compensation process after unilateral carotid artery ligation. With the superiority of high resolution, OCT is an effective technology in monitoring results of carotid artery after ligation.

Ultrasound Common Carotid Artery Segmentation Based on Active Shape Model

PubMed Central

Yang, Xin; Jin, Jiaoying; Xu, Mengling; Wu, Huihui; He, Wanji; Yuchi, Ming; Ding, Mingyue

2013-01-01

Carotid atherosclerosis is a major reason of stroke, a leading cause of death and disability. In this paper, a segmentation method based on Active Shape Model (ASM) is developed and evaluated to outline common carotid artery (CCA) for carotid atherosclerosis computer-aided evaluation and diagnosis. The proposed method is used to segment both media-adventitia-boundary (MAB) and lumen-intima-boundary (LIB) on transverse views slices from three-dimensional ultrasound (3D US) images. The data set consists of sixty-eight, 17 × 2 × 2, 3D US volume data acquired from the left and right carotid arteries of seventeen patients (eight treated with 80 mg atorvastatin and nine with placebo), who had carotid stenosis of 60% or more, at baseline and after three months of treatment. Manually outlined boundaries by expert are adopted as the ground truth for evaluation. For the MAB and LIB segmentations, respectively, the algorithm yielded Dice Similarity Coefficient (DSC) of 94.4% ± 3.2% and 92.8% ± 3.3%, mean absolute distances (MAD) of 0.26 ± 0.18 mm and 0.33 ± 0.21 mm, and maximum absolute distances (MAXD) of 0.75 ± 0.46 mm and 0.84 ± 0.39 mm. It took 4.3 ± 0.5 mins to segment single 3D US images, while it took 11.7 ± 1.2 mins for manual segmentation. The method would promote the translation of carotid 3D US to clinical care for the monitoring of the atherosclerotic disease progression and regression. PMID:23533535

“Protected” Wallstenting of Atheromatous Stenoses at the Carotid Bifurcation

PubMed Central

Théron, J.G.; Guimaraens, L.J.; Casasco, A.E.; Courtheoux, P.G.; Beaujeux, R.L.; Rufenacht, D.A.; Coskun, O.; Sola, M.T.; Constans, J.-M.; Martin, J.-B.

2003-01-01

Summary Atheromatous stenoses at the carotid bifurcation were treated by angioplasty and Wallstenting with cerebral protection obtained in most cases by temporary occlusion of the internal carotid artery. 287 carotid stenoses were treated in 233 patients. The stenosis was symptomatic in 79% of cases. All patients presented either a stenosis of >70% with significant impairment of the cerebral circulation (281 cases) or a symptomatic ulcerated plaque (six cases). A self-mounted protection system was used in 177 cases, the Percusurge Guardwire protection device in 98 cases an EPI filter in 12 cases. There was a contralateral internal carotid occlusion in 13% of cases. A combined stenting (vertebral, siphon, subclavian) was performed in 14% of cases. A Rolling membrane Wallstent was used in 84 patients, a first generation Easy Wallstent in 38 cases, a “Carotid” Easy Wallstent 35 in 55 cases and monorail 14 in 110 cases. Full opening of the stenosis was obtained in 98% of patients with correction of the arterial curve and improvement of the cerebral vascular supply. There were 0.7% cases with transient symptomatic neurological complications and 2% with permanent sequelae mainly related to avoidable inadequacy in flushing or to the insufficient radial force of the first generation Easy Wallstent. There were no per and one post-procedural cardiac complication (0.6%) in the s165 cases performed with the “Carotid” Easy Wallstent. Follow-up angiograms showed O.7% of restenoses. Still in evolution, endovascular treatment of atheromatous stenoses at the carotid bifurcation with cerebral protection and stenting is a promising alternative technique to surgery. The association of Carotid Easy Wallstent 14 monorail and Percusurge Guardwire appears to be currently satisfactory. PMID:20591262

Carotid Plaque Lipid Content and Fibrous Cap Status Predict Systemic CV Outcomes: The MRI Substudy in AIM-HIGH.

PubMed

Sun, Jie; Zhao, Xue-Qiao; Balu, Niranjan; Neradilek, Moni B; Isquith, Daniel A; Yamada, Kiyofumi; Cantón, Gádor; Crouse, John R; Anderson, Todd J; Huston, John; O'Brien, Kevin; Hippe, Daniel S; Polissar, Nayak L; Yuan, Chun; Hatsukami, Thomas S

2017-03-01

The aim of this study was to investigate whether and what carotid plaque characteristics predict systemic cardiovascular outcomes in patients with clinically established atherosclerotic disease. Advancements in atherosclerosis imaging have allowed assessment of various plaque characteristics, some of which are more directly linked to the pathogenesis of acute cardiovascular events compared to plaque burden. As part of the event-driven clinical trial AIM-HIGH (Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides: Impact on Global Health Outcomes), subjects with clinically established atherosclerotic disease underwent multicontrast carotid magnetic resonance imaging (MRI) to detect plaque tissue composition and high-risk features. Prospective associations between MRI measurements and the AIM-HIGH primary endpoint (fatal and nonfatal myocardial infarction, ischemic stroke, hospitalization for acute coronary syndrome, and symptom-driven revascularization) were analyzed using Cox proportional hazards survival models. Of the 232 subjects recruited, 214 (92.2%) with diagnostic image quality constituted the study population (82% male, mean age 61 ± 9 years, 94% statin use). During median follow-up of 35.1 months, 18 subjects (8.4%) reached the AIM-HIGH endpoint. High lipid content (hazard ratio [HR] per 1 SD increase in percent lipid core volume: 1.57; p = 0.002) and thin/ruptured fibrous cap (HR: 4.31; p = 0.003) in carotid plaques were strongly associated with the AIM-HIGH endpoint. Intraplaque hemorrhage had a low prevalence (8%) and was marginally associated with the AIM-HIGH endpoint (HR: 3.00; p = 0.053). High calcification content (HR per 1 SD increase in percent calcification volume: 0.66; p = 0.20), plaque burden metrics, and clinical risk factors were not significantly associated with the AIM-HIGH endpoint. The associations between carotid plaque characteristics and the AIM-HIGH endpoint changed little after adjusting for

Physical and computational fluid dynamics models for the hemodynamics of the artiodactyl carotid rete.

PubMed

O'Brien, Haley D; Bourke, Jason

2015-12-07

In the mammalian order Artiodactyla, the majority of arterial blood entering the intracranial cavity is supplied by a large arterial meshwork called the carotid rete. This vascular structure functionally replaces the internal carotid artery. Extensive experimentation has demonstrated that the artiodactyl carotid rete drives one of the most effective selective brain cooling mechanisms among terrestrial vertebrates. Less well understood is the impact that the unique morphology of the carotid rete may have on the hemodynamics of blood flow to the cerebrum. It has been hypothesized that, relative to the tubular internal carotid arteries of most other vertebrates, the highly convoluted morphology of the carotid rete may increase resistance to flow during extreme changes in cerebral blood pressure, essentially protecting the brain by acting as a resistor. We test this hypothesis by employing simple and complex physical models to a 3D surface rendering of the carotid rete of the domestic goat, Capra hircus. First, we modeled the potential for increased resistance across the carotid rete using an electrical circuit analog. The extensive branching of the rete equates to a parallel circuit that is bound in series by single tubular arteries, both upstream and downstream. This method calculated a near-zero increase in resistance across the rete. Because basic equations do not incorporate drag, shear-stress, and turbulence, we used computational fluid dynamics to simulate the impact of these computationally intensive factors on resistance. Ultimately, both simple and complex models demonstrated negligible changes in resistance and blood pressure across the arterial meshwork. We further tested the resistive potential of the carotid rete by simulating blood pressures known to occur in giraffes. Based on these models, we found resistance (and blood pressure mitigation as a whole) to be an unlikely function for the artiodactyl carotid rete. Copyright © 2015 Elsevier Ltd. All

Association between triglyceride/HDL cholesterol ratio and carotid atherosclerosis in postmenopausal middle-aged women.

PubMed

Masson, Walter; Siniawski, Daniel; Lobo, Martín; Molinero, Graciela; Huerín, Melina

2016-01-01

The triglyceride/HDL cholesterol ratio, as a surrogate marker of insulin resistance, may be associated to presence of subclinical carotid atherosclerosis in postmenopausal women. The aim of this study was to explore this association. Women (last menstrual period≥2 years) in primary prevention up to 65 years of age were recruited. Association between the triglyceride/HDL cholesterol (HDL-C) ratio and presence of carotid plaque, assessed by ultrasonography, was analyzed. ROC analysis was performed, determining the precision of this ratio to detect carotid plaque. A total of 332 women (age 57±5 years) were recruited. Triglyceride/HDL-C ratio was 2.35±1.6. Prevalence of carotid plaque was 29%. Women with carotid plaque had higher triglyceride/HDL-C ratios (3.33±1.96 vs. 2.1±1.2, P<.001) than women with no carotid plaque. A positive relationship was seen between quintiles of this ratio and prevalence of carotid plaque (p<.001). Regardless of other risk factors, women with higher triglyceride/HDL-C ratios were more likely to have carotid plaque (odds ratio 1.47, 95% confidence interval 1.20-1.79, P<.001). The area under the curve of the triglyceride/HDL-C ratio to detect carotid plaque was .71 (95% confidence interval .65 to .76), and the optimal cut-off point was 2.04. In postmenopausal women in primary prevention, insulin resistance, estimated from the triglyceride/HDL-C ratio, was independently associated to a greater probability of carotid plaque. A value of such ratio greater than 2 may be used for assessing cardiovascular risk in this particular group of women. Copyright © 2016 SEEN. Publicado por Elsevier España, S.L.U. All rights reserved.

Retrograde Suction Decompression with an Inahara Carotid Shunt for Clipping a Large Distal Internal Carotid Artery Aneurysm.

PubMed

Park, Yong Sook; Nam, Taek Kyun

2017-03-01

We describe a technique to clip a large internal carotid artery (ICA) aneurysm via a retrograde suction decompression (RSD). A large aneurysm in the right distal ICA involving the bifurcation region measuring 1.2×1.1×0.7 cm with posterior projection was managed with assisted RSD technique. The anterior choroidal artery emerged from the side wall of the aneurysm. An Inahara shunt was inserted into the ICA with neck dissection, and RSD was applied after completely clipping the aneurysm. RSD with an Inahara carotid shunt is useful for complete visualization of the aneurysm, including its surrounding structures, and for proximal control of the parent vessels, subsequently achieving satisfactory clip placement.

A uni-extension study on the ultimate material strength and extreme extensibility of atherosclerotic tissue in human carotid plaques.

PubMed

Teng, Zhongzhao; Feng, Jiaxuan; Zhang, Yongxue; Sutcliffe, Michael P F; Huang, Yuan; Brown, Adam J; Jing, Zaiping; Lu, Qingsheng; Gillard, Jonathan H

2015-11-05

Atherosclerotic plaque rupture occurs when mechanical loading exceeds its material strength. Mechanical analysis has been shown to be complementary to the morphology and composition for assessing vulnerability. However, strength and stretch thresholds for mechanics-based assessment are currently lacking. This study aims to quantify the ultimate material strength and extreme extensibility of atherosclerotic components from human carotid plaques. Tissue strips of fibrous cap, media, lipid core and intraplaque hemorrhage/thrombus were obtained from 21 carotid endarterectomy samples of symptomatic patients. Uni-extension test with tissue strips was performed until they broke or slid. The Cauchy stress and stretch ratio at the peak loading of strips broken about 2mm away from the clamp were used to characterize their ultimate strength and extensibility. Results obtained indicated that ultimate strength of fibrous cap and media were 158.3 [72.1, 259.3] kPa (Median [Inter quartile range]) and 247.6 [169.0, 419.9] kPa, respectively; those of lipid and intraplaque hemorrhage/thrombus were 68.8 [48.5, 86.6] kPa and 83.0 [52.1, 124.9] kPa, respectively. The extensibility of each tissue type were: fibrous cap - 1.18 [1.10, 1.27]; media - 1.21 [1.17, 1.32]; lipid - 1.25 [1.11, 1.30] and intraplaque hemorrhage/thrombus - 1.20 [1.17, 1.44]. Overall, the strength of fibrous cap and media were comparable and so were lipid and intraplaque hemorrhage/thrombus. Both fibrous cap and media were significantly stronger than either lipid or intraplaque hemorrhage/thrombus. All atherosclerotic components had similar extensibility. Moreover, fibrous cap strength in the proximal region (closer to the heart) was lower than that of the distal. These results are helpful in understanding the material behavior of atherosclerotic plaques. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

A Correlational Study on Cerebral Microbleeds and Carotid Atherosclerosis in Patients with Ischemic Stroke.

PubMed

Zhao, Fang-Fang; Gao, Hao-Yuan; Gao, Yuan; Zhao, Zhuan; Li, Juan; Ning, Fang-Bo; Zhang, Xin-Na; Wang, Zhi-Gao; Yu, Ai-Ling; Guo, Yan-Yong; Sun, Bao-Liang

2018-05-11

This study aimed to investigate the correlation between cerebral microbleeds and carotid atherosclerosis in patients with ischemic stroke. Patients with ischemic stroke treated in a hospital in China from 2016 to 2017 were enrolled in the study. Based on the results from susceptibility-weighted imaging, the patients were divided into cerebral microbleed and noncerebral microbleed groups. The degree of carotid atherosclerosis was assessed with carotid intima-media thickness (CIMB) and Crouse score of carotid plaque. The details of patients' demographic information, cerebrovascular disease-related risk factors, carotid atherosclerosis indices, cerebral microbleed distribution, and grading were recorded, compared, and analyzed. Logistic regression analysis of the 198 patients showed that CIMB and Crouse score were significantly correlated with the occurrence of cerebral microbleeds. The CIMB thickening group (P = .03) and the plaque group (P = .01) were more susceptible to cerebral microbleeds. In the distribution of cerebral microbleed sites, Crouse scores were the highest in the mixed group and showed a statistically significant difference (P < .01). As the degree of carotid atherosclerosis increased, the average number of cerebral microbleeds also increased (P < .01). The receiver operating characteristic curve analysis of the carotid atherosclerosis indices showed a statistically significant difference. The CIMB value combined with the Crouse score was the best indicator (P < .01). In patients with ischemic stroke, cerebral microbleeds are closely related to carotid atherosclerosis. Active control of carotid atherosclerosis is important to prevent cerebral microbleeds in patients with ischemic stroke. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Advances and perspectives in in vitro human gut fermentation modeling.

PubMed

Payne, Amanda N; Zihler, Annina; Chassard, Christophe; Lacroix, Christophe

2012-01-01

The gut microbiota is a highly specialized organ containing host-specific assemblages of microbes whereby metabolic activity directly impacts human health and disease. In vitro gut fermentation models present an unmatched opportunity of performing studies frequently challenged in humans and animals owing to ethical concerns. Multidisciplinary systems biology analyses supported by '-omics' platforms remain widely neglected in the field of in vitro gut fermentation modeling but are key to advancing the significance of these models. Model-driven experimentation using a combination of in vitro gut fermentation and in vitro human cell models represent an advanced approach in identifying complex host-microbe interactions and niches central to gut fermentation processes. The aim of this review is to highlight the advances and challenges exhibited by in vitro human gut fermentation modeling. Copyright © 2011 Elsevier Ltd. All rights reserved.

Factors affecting cardiovascular and cerebrovascular complications of carotid artery stenting in Northern Michigan: A retrospective study.

PubMed

Mammo, Dalia F; Cheng, Chin-I; Ragina, Neli P; Alani, Firas

This study seeks to identify factors associated with periprocedural complications of carotid artery stenting (CAS) to best understand CAS complication rates and optimize patient outcomes. Periprocedural complications include major adverse cardiovascular and cerebrovascular events (MACCE) that include myocardial infarction (MI), stroke, or death. We retrospectively analyzed 181 patients from Northern Michigan who underwent CAS. Rates of stroke, MI, and death occurring within 30days post-procedure were examined. Associations of open vs. closed cell stent type, demographics, comorbidities, and symptomatic carotid stenosis were compared to determine significance. All patients had three NIH Stroke Scale (NIHSS) exams: at baseline, 24h post-procedure, and at the one-month visit. Cardiac enzymes were measured twice in all patients, within 24h post-procedure. All patients were treated with dual anti-platelet therapy for at least 6months post-procedure. Three patients (1.66%) experienced a major complication within one-month post-procedure. These complications included one MI (0.55%), one stroke (0.55%), and one death (0.55%). The following variable factors were not associated with the occurrence of MACCE complications within 30days post-procedure: stent design (open vs. closed cell) (p=1.000), age ≥80 (p=0.559), smoking history (p=0.569), hypertension (p=1.000), diabetes (p=1.000), and symptomatic carotid stenosis (p=0.254). Age of 80years old or above, symptomatic carotid stenosis, open-cell stent design, and history of diabetes, smoking, or hypertension were not found to have an association with MACCE within 1month after CAS. Future studies using a greater sample size will be beneficial to better assess periprocedural complication risks of CAS, while also considering the effect of operator experience and technological advancements on decreasing periprocedural complication rates. Copyright © 2017 Elsevier Inc. All rights reserved.

DIRECT NUMERICAL SIMULATION OF TRANSITIONAL FLOW IN A STENOSED CAROTID BIFURCATION

PubMed Central

Lee, Seung E.; Lee, Sang-Wook; Fischer, Paul F.; Bassiouny, Hisham S.; Loth, Francis

2008-01-01

The blood flow dynamics of a stenosed, subject-specific, carotid bifurcation were numerically simulated using the spectral element method. Pulsatile inlet conditions were based on in vivo color Doppler ultrasound measurements of blood velocity. The results demonstrated the transitional or weakly turbulent state of the blood flow, which featured rapid velocity and pressure fluctuations in the post-stenotic region of the internal carotid artery during systole and laminar flow during diastole. High-frequency vortex shedding was greatest downstream of the stenosis during the deceleration phase of systole. Velocity fluctuations had a frequency within the audible range of 100–300 Hz. Instantaneous wall shear stress within the stenosis was relatively high during systole (~25-45 Pa) compared to that in a healthy carotid. In addition, high spatial gradients of wall shear stress were present due to flow separation on the inner wall. Oscillatory flow reversal and low pressure were observed distal to the stenosis in the internal carotid artery. This study predicts the complex flow field, the turbulence levels and the distribution of the biomechanical stresses present in vivo within a stenosed carotid artery. PMID:18656199

Utility of intravascular ultrasound examination during carotid stenting.

PubMed

Joan, M Mellado; Moya, B Gómez; Agustí, F Pañella; Vidal, R García; Arjona, Y Abril; Alija, M P Fariñas; Paredero, V Martín

2009-01-01

Intravascular ultrasound (IVUS) examination may provide useful information during endovascular procedures. However, its actual clinical utility for carotid stenting remains unclear. We evaluated the usefulness of IVUS as a complementary tool during endovascular procedures in the carotid arteries and its impact on the modification of the therapeutic strategy. Between April 2006 and April 2007, 18 symptomatic patients (nine with transient ischemic attack, nine with stroke) underwent angioplasty and stenting of >70% stenosis of the internal carotid artery (ICA). Target lesions were identified with preoperative duplex scanning and further confirmed at angiography. Intraoperative IVUS examination was performed in all patients. Multilevel measurement of the artery as well as virtual histology images, before and after stenting, were obtained. The technique was 100% successful. There were no complications at the femoral puncture site and no neurological or other events. Compared with angiography, IVUS findings showed an average arterial diameter that was greater than 1.64+/-0.22mm. Based on virtual histology information, endovascular treatment was excluded in two patients and carotid endarterectomy was performed. Type or size of the stent was modified after IVUS examination in eight cases. IVUS examination provides complementary information to that obtained using conventional diagnostic procedures. It may be useful for characterizing the composition and measurement of the target lesion, choosing the type and size of the stent, and evaluating the results after the procedure.

History of carotid surgery: from ancient greeks to the modern era.

PubMed

Tallarita, Tiziano; Gerbino, Maurizio; Gurrieri, Carmelina; Lanzino, Giuseppe

2013-12-01

A relationship between decreased carotid arterial flow and apoplectic manifestations was already suspected by the ancient Greeks. Early attempts at carotid surgery, however, were limited to emergency arterial ligation in patients with neck trauma. Attempts to suture arterial stumps together to restore blood flow paved the way for Carrel's revolutionary idea of reconstructing the resected or injured arterial segment with an interposition vein graft. DeBakey and Eastcott were the first to perform carotid endarterectomy in North America and the United Kingdom, respectively. In 1959, DeBakey proposed a cooperative study to assess the effectiveness of carotid endarterectomy in the treatment and prevention of ischemic cerebrovascular disease. The study was officially designated the Joint Study of Extracranial Arterial Occlusion and represented the first trial in the United States in which large numbers of patients were randomly allocated to surgical or nonsurgical therapy.

External Carotid-Internal Jugular Fistula as a Late Complication After Carotid Endarterectomy: A Rare Case

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bakar, Bulent, E-mail: bulentbanrs@yahoo.com; Cekirge, Saruhan; Tekkok, Ismail Hakki

2011-02-15

A 66-year-old man presented with mild amnesia, progressive fatigue, ataxia, visual hallucinations, and debility. His past medical history included right-sided carotid endarterectomy performed elsewhere 6 years previously. Cranial magnetic resonance imaging showed left parieto-occipital arteriovenous malformation-like tortous vessels, venous congestion, and ischemic areas. Cerebral angiography showed right-sided compound external carotid artery-internal jugular vein (IJV) fistula, and distal occlusion of the right IJV. Transvenous embolization via contralateral IJV was performed, and the fistula, together with fistulous portion of the distal IJV, was sealed using coils. Two years later, patient is well with normal neurologic examination findings. The presence of an arteriovenousmore » communication after vascular surgery is a serious complication with potential long-term effects and therefore should be diagnosed and treated as promptly as possible.« less

Automated landmarking and geometric characterization of the carotid siphon.

PubMed

Bogunović, Hrvoje; Pozo, José María; Cárdenes, Rubén; Villa-Uriol, María Cruz; Blanc, Raphaël; Piotin, Michel; Frangi, Alejandro F

2012-05-01

The geometry of the carotid siphon has a large variability between subjects, which has prompted its study as a potential geometric risk factor for the onset of vascular pathologies on and off the internal carotid artery (ICA). In this work, we present a methodology for an objective and extensive geometric characterization of carotid siphon parameterized by a set of anatomical landmarks. We introduce a complete and automated characterization pipeline. Starting from the segmentation of vasculature from angiographic image and its centerline extraction, we first identify ICA by characterizing vessel tree bifurcations and training a support vector machine classifier to detect ICA terminal bifurcation. On ICA centerline curve, we detect anatomical landmarks of carotid siphon by modeling it as a sequence of four bends and selecting their centers and interfaces between them. Bends are detected from the trajectory of the curvature vector expressed in the parallel transport frame of the curve. Finally, using the detected landmarks, we characterize the geometry in two complementary ways. First, with a set of local and global geometric features, known to affect hemodynamics. Second, using large deformation diffeomorphic metric curve mapping (LDDMCM) to quantify pairwise shape similarity. We processed 96 images acquired with 3D rotational angiography. ICA identification had a cross-validation success rate of 99%. Automated landmarking was validated by computing limits of agreement with the reference taken to be the locations of the manually placed landmarks averaged across multiple observers. For all but one landmark, either the bias was not statistically significant or the variability was within 50% of the inter-observer one. The subsequently computed values of geometric features and LDDMCM were commensurate to the ones obtained with manual landmarking. The characterization based on pair-wise LDDMCM proved better in classifying the carotid siphon shape classes than the one

Plaque echodensity and textural features are associated with histologic carotid plaque instability.

PubMed

Doonan, Robert J; Gorgui, Jessica; Veinot, Jean P; Lai, Chi; Kyriacou, Efthyvoulos; Corriveau, Marc M; Steinmetz, Oren K; Daskalopoulou, Stella S

2016-09-01

Carotid plaque echodensity and texture features predict cerebrovascular symptomatology. Our purpose was to determine the association of echodensity and textural features obtained from a digital image analysis (DIA) program with histologic features of plaque instability as well as to identify the specific morphologic characteristics of unstable plaques. Patients scheduled to undergo carotid endarterectomy were recruited and underwent carotid ultrasound imaging. DIA was performed to extract echodensity and textural features using Plaque Texture Analysis software (LifeQ Medical Ltd, Nicosia, Cyprus). Carotid plaque surgical specimens were obtained and analyzed histologically. Principal component analysis (PCA) was performed to reduce imaging variables. Logistic regression models were used to determine if PCA variables and individual imaging variables predicted histologic features of plaque instability. Image analysis data from 160 patients were analyzed. Individual imaging features of plaque echolucency and homogeneity were associated with a more unstable plaque phenotype on histology. These results were independent of age, sex, and degree of carotid stenosis. PCA reduced 39 individual imaging variables to five PCA variables. PCA1 and PCA2 were significantly associated with overall plaque instability on histology (both P = .02), whereas PCA3 did not achieve statistical significance (P = .07). DIA features of carotid plaques are associated with histologic plaque instability as assessed by multiple histologic features. Importantly, unstable plaques on histology appear more echolucent and homogeneous on ultrasound imaging. These results are independent of stenosis, suggesting that image analysis may have a role in refining the selection of patients who undergo carotid endarterectomy. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Two Automated Techniques for Carotid Lumen Diameter Measurement: Regional versus Boundary Approaches.

PubMed

Araki, Tadashi; Kumar, P Krishna; Suri, Harman S; Ikeda, Nobutaka; Gupta, Ajay; Saba, Luca; Rajan, Jeny; Lavra, Francesco; Sharma, Aditya M; Shafique, Shoaib; Nicolaides, Andrew; Laird, John R; Suri, Jasjit S

2016-07-01

The degree of stenosis in the carotid artery can be predicted using automated carotid lumen diameter (LD) measured from B-mode ultrasound images. Systolic velocity-based methods for measurement of LD are subjective. With the advancement of high resolution imaging, image-based methods have started to emerge. However, they require robust image analysis for accurate LD measurement. This paper presents two different algorithms for automated segmentation of the lumen borders in carotid ultrasound images. Both algorithms are modeled as a two stage process. Stage one consists of a global-based model using scale-space framework for the extraction of the region of interest. This stage is common to both algorithms. Stage two is modeled using a local-based strategy that extracts the lumen interfaces. At this stage, the algorithm-1 is modeled as a region-based strategy using a classification framework, whereas the algorithm-2 is modeled as a boundary-based approach that uses the level set framework. Two sets of databases (DB), Japan DB (JDB) (202 patients, 404 images) and Hong Kong DB (HKDB) (50 patients, 300 images) were used in this study. Two trained neuroradiologists performed manual LD tracings. The mean automated LD measured was 6.35 ± 0.95 mm for JDB and 6.20 ± 1.35 mm for HKDB. The precision-of-merit was: 97.4 % and 98.0 % w.r.t to two manual tracings for JDB and 99.7 % and 97.9 % w.r.t to two manual tracings for HKDB. Statistical tests such as ANOVA, Chi-Squared, T-test, and Mann-Whitney test were conducted to show the stability and reliability of the automated techniques.

Resection of recurrent neck cancer with carotid artery replacement.

PubMed

Illuminati, Giulio; Schneider, Fabrice; Minni, Antonio; Calio, Francesco G; Pizzardi, Giulia; Ricco, Jean-Baptiste

2016-05-01

The management of patients with recurrent neck cancer invading the carotid artery is controversial. The purpose of this study was to evaluate overall survival rate, primary patency of vascular reconstructions, and quality-adjusted life-years (QALYs) after en bloc resection of the carotid artery and tumor with in-line polytetrafluoroethylene (PTFE) carotid grafting, followed by radiotherapy. From 2000 to 2014, 31 consecutive patients with recurrent neck cancer invading the carotid artery underwent en bloc resection and simultaneous carotid artery reconstruction with a PTFE graft, which was associated in 18 cases with a myocutaneous flap. The primary tumor was a squamous cell carcinoma of the larynx in 17 patients and of the hypopharynx in 7, an undifferentiated carcinoma of unknown origin in 4, and an anaplastic carcinoma of the thyroid in 3. All of the patients underwent postoperative radiotherapy (50-70 Gy), and 10 of them also underwent chemotherapy (doxorubicin and cisplatin). None of the patients died or sustained a stroke during the first 30 days after the index procedure. Postoperative morbidity consisted of 6 transitory dysphagias, 3 vocal cord palsies, 2 wound dehiscences, 1 transitory mandibular claudication, and 1 partial myocutaneous flap necrosis. No graft infection occurred during follow-up. Fifteen patients (48%) died from metastatic cancer during a mean follow-up of 45.4 months (range, 8-175 months). None of the patients showed evidence of local recurrence, stroke, or thrombosis of the carotid reconstruction. The 5-year survival rate was 49 ± 10%. The overall number of QALYs was 3.12 (95% confidence interval, 1.87-4.37) with a significant difference between patients without metastasis at the time of redo surgery (n = 26; QALYs, 3.74) and those with metastasis (n = 5; QALYs, 0.56; P = .005). QALYs were also significantly improved in patients with cancer of the larynx (n = 17; QALYs, 4.69) compared to patients presenting with other types of

Sedentary behaviour patterns and carotid intima-media thickness in Spanish healthy adult population.

PubMed

García-Hermoso, Antonio; Martínez-Vizcaíno, Vicente; Recio-Rodríguez, José Ignacio; Sánchez-López, Mairena; Gómez-Marcos, Manuel Ángel; García-Ortiz, Luis

2015-04-01

The aim of this study was to analyze the association between sedentary behaviour, as assessed by an accelerometer, and mean carotid intima-media thickness (IMT). The study included 263 healthy subjects belonging to the EVIDENT study (59.3% women). Carotid IMT was measured by carotid ultrasonography. Sedentary behaviour was measured objectively over 7 days using ActiGraph accelerometers. Thresholds of 10 consecutive minutes were used to establish sedentary bouts, and assess the number (n/day), and length ≥10 min (min/day). Total sedentary time and sedentary time in bouts ≥10 min was higher in participants with a larger mean carotid IMT (>P75). Otherwise, this sedentary time in bouts ≥10 min parameter was weakly associated with augmented carotid IMT injury in the logistic regression model. Total sedentary time and sedentary time in bouts ≥10 min, as assessed by accelerometer, was positively but weakly associated with carotid IMT. Equally, this sedentary time in bouts ≥10 min was associated with carotid injury, but disappears after adjusting for potential confounders. These findings support that reducing sedentary time and increasing breaks in bouts of sedentary time might represent a useful additional strategy in the cardiovascular disease prevention. Clinical Trials.gov Identifier: NCT01083082. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Carotid plaque-thickness and common carotid IMT show additive value in cardiovascular risk prediction and reclassification.

PubMed

Amato, Mauro; Veglia, Fabrizio; de Faire, Ulf; Giral, Philippe; Rauramaa, Rainer; Smit, Andries J; Kurl, Sudhir; Ravani, Alessio; Frigerio, Beatrice; Sansaro, Daniela; Bonomi, Alice; Tedesco, Calogero C; Castelnuovo, Samuela; Mannarino, Elmo; Humphries, Steve E; Hamsten, Anders; Tremoli, Elena; Baldassarre, Damiano

2017-08-01

Carotid plaque size and the mean common carotid intima-media thickness measured in plaque-free areas (PF CC-IMT mean ) have been identified as predictors of vascular events (VEs), but their complementarity in risk prediction and stratification is still unresolved. The aim of this study was to evaluate the independence of carotid plaque thickness and PF CC-IMT mean in cardiovascular risk prediction and risk stratification. The IMPROVE-study is a European cohort (n = 3703), where the thickness of the largest plaque detected in the whole carotid tree was indexed as cIMT max . PF CC-IMT mean was also assessed. Hazard Ratios (HR) comparing the top quartiles of cIMT max and PF CC-IMT mean versus their respective 1-3 quartiles were calculated using Cox regression. After a 36.2-month follow-up, there were 215 VEs (125 coronary, 73 cerebral and 17 peripheral). Both cIMT max and PF CC-IMT mean were mutually independent predictors of combined-VEs, after adjustment for center, age, sex, risk factors and pharmacological treatment [HR (95% CI) = 1.98 (1.47, 2.67) and 1.68 (1.23, 2.29), respectively]. Both variables were independent predictors of cerebrovascular events (ischemic stroke, transient ischemic attack), while only cIMT max was an independent predictor of coronary events (myocardial infarction, sudden cardiac death, angina pectoris, angioplasty, coronary bypass grafting). In reclassification analyses, PF CC-IMT mean significantly adds to a model including both Framingham Risk Factors and cIMT max (Integrated Discrimination Improvement; IDI = 0.009; p = 0.0001) and vice-versa (IDI = 0.02; p < 0.0001). cIMT max and PF CC-IMT mean are independent predictors of VEs, and as such, they should be used as additive rather than alternative variables in models for cardiovascular risk prediction and reclassification. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Mycotic Pseudoaneurysm of Internal Carotid Artery Secondary to Lemierre's Syndrome, How to Do It.

PubMed

Benedetto, Filippo; Barillà, David; Pipitò, Narayana; Derone, Graziana; Cutrupi, Andrea; Barillà, Chiara

2017-10-01

We report the case of a patient with internal carotid artery (ICA) mycotic pseudoaneurysm secondary to Lemierre's syndrome, urgently treated. A 75-year-old man presented to E.R. with a left swelling lesion of the neck and complaining left visions lost since that morning, fever, hypotension, and dyspnea. Since 15 days before developing symptoms, he had sore throat and odynophagia treated with a broad coverage of antibiotic therapy for presumed streptococcal pharyngitis. Preoperative computed tomography angiography images revealed a circular lesion, involving the common carotid artery, carotid bulb, and the proximal part of the internal and external carotid arteries. A pseudoaneurysm of the ICA was detected, and the jugular vein was compressed. A Cormier carotid vein graft bypass was performed. Lemierre's syndrome is a rare syndrome, but it is rarer the carotid artery pseudoaneurysm secondary to Lemierre's syndrome. Surgical treatment is safe and durable in patients with severe infection involving the neck. Copyright © 2017 Elsevier Inc. All rights reserved.

Consciousness in humans and non-human animals: recent advances and future directions

PubMed Central

Boly, Melanie; Seth, Anil K.; Wilke, Melanie; Ingmundson, Paul; Baars, Bernard; Laureys, Steven; Edelman, David B.; Tsuchiya, Naotsugu

2013-01-01

This joint article reflects the authors' personal views regarding noteworthy advances in the neuroscience of consciousness in the last 10 years, and suggests what we feel may be promising future directions. It is based on a small conference at the Samoset Resort in Rockport, Maine, USA, in July of 2012, organized by the Mind Science Foundation of San Antonio, Texas. Here, we summarize recent advances in our understanding of subjectivity in humans and other animals, including empirical, applied, technical, and conceptual insights. These include the evidence for the importance of fronto-parietal connectivity and of “top-down” processes, both of which enable information to travel across distant cortical areas effectively, as well as numerous dissociations between consciousness and cognitive functions, such as attention, in humans. In addition, we describe the development of mental imagery paradigms, which made it possible to identify covert awareness in non-responsive subjects. Non-human animal consciousness research has also witnessed substantial advances on the specific role of cortical areas and higher order thalamus for consciousness, thanks to important technological enhancements. In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states. Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence. Along with reviewing these findings, each author suggests future avenues for research in their field of investigation. PMID:24198791

The carotid body in Sudden Infant Death Syndrome.

PubMed

Porzionato, Andrea; Macchi, Veronica; Stecco, Carla; De Caro, Raffaele

2013-01-01

The aim of the present study is to provide a review of cytochemical, clinical and experimental data indicating disruption of perinatal carotid body maturation as one of the possible mechanisms underlying SIDS pathogenesis. SIDS victims have been reported to show alterations in respiratory regulation which may partly be ascribed to peripheral arterial chemoreceptors. Carotid body findings in SIDS victims, although not entirely confirmed by other authors, have included reductions in glomic tissue volume and cytoplamic granules of type I cells, changes in cytological composition (higher percentages of progenitor and type II cells) and increases in dopamine and noradrenaline contents. Prematurity and environmental factors, such as exposure to tobacco smoke, substances of abuse, hyperoxia and continuous or intermittent hypoxia, increase the risk of SIDS and are known to affect carotid body functional and structural maturation adversely, supporting a role for peripheral arterial chemoreceptors in SIDS. Copyright © 2012 Elsevier B.V. All rights reserved.

Carotid-cavernous fistula after functional endoscopic sinus surgery.

PubMed

Karaman, Emin; Isildak, Huseyin; Haciyev, Yusuf; Kaytaz, Asim; Enver, Ozgun

2009-03-01

Carotid-cavernous fistulas (CCFs) are anomalous communications between the carotid arterial system and the venous cavernous sinus. They can arise because of spontaneous or trauma causes. Most caroticocavernous fistulas are of spontaneous origin and unknown etiology. Spontaneous CCF may also be associated with cavernous sinus pathology such as arteriosclerotic changes of the arterial wall, fibromuscular dysplasia, or Ehler-Danlos syndrome. Traumatic CCFs may occur after either blunt or penetrating head trauma. Their clinical presentation is related to their size and to the type of venous drainage, which can lead to a variety of symptoms, such as visual loss, proptosis, bruit, chemosis, cranial nerve impairment, intracranial hemorrhage (rare), and so on. Treatment by endovascular transarterial embolization with electrolytically detachable coils is a very effective method for CCF with good outcomes. Carotid-cavernous fistulas have been rarely reported after craniofacial surgery and are uncommon pathologies in otolaryngology practice. In this study, we report a 40-year-old woman with CCF secondary to blunt trauma of functional endoscopic sinus surgery.

Relationship between increased carotid artery stiffness and idiopathic subjective tinnitus.

PubMed

Bayraktar, C; Taşolar, S

2017-05-01

Tinnitus is defined as perception of sound with no external stimulus, and can separate into pulsatile and non-pulsatile types. Arterial stiffness is a parameter that can predict the cardiovascular event and associated with incidence of stroke. It has been shown that increased arterial stiffness may lead to microvascular damage in brain. Our aim was to assess the arterial stiffness of the carotid system in the development and severity of idiopathic subjective tinnitus. Forty subjective tinnitus patients and 40 age- and sex-matched controls were enrolled in the study. The parameters obtained from the participants included pure tone hearing (dB), serum lipid profile (mg/dl), fasting glucose (mg/dl), blood pressure (mmHg), and body mass index (BMI, kg/m 2 ). The common carotid artery (CCA) stiffness index, Young's elastic modulus (YEM), common carotid intima-media thickness (CIMT), peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI), pulsatility index (PI), vessel diameter, mean velocity (MV), and volume flow (VF) were measured in both the right and left common carotid arteries in both groups. The CCA stiffness index, YEM measurements, right CIMT, and left PI were found to be significantly higher in the patients than those in the control group (p < 0.05). With regard to the severity of the tinnitus and the patient characteristics, there was a significant positive correlation with the CCA stiffness index, YEM measurements, left CIMT, and neutrophil-to-lymphocyte ratio (NLR). However, only the right and left CCA stiffness parameters were found to be statistically significant in the multivariate analysis as independent predictors of a moderate to high degree of tinnitus. The increased stiffness index of the common carotid arteries was significantly associated with the formation and severity of tinnitus. Therefore, an assessment of the carotideal system may be helpful in these patients.

Chronic Interactions Between Carotid Baroreceptors and Chemoreceptors in Obesity Hypertension.

PubMed

Lohmeier, Thomas E; Iliescu, Radu; Tudorancea, Ionut; Cazan, Radu; Cates, Adam W; Georgakopoulos, Dimitrios; Irwin, Eric D

2016-07-01

Carotid bodies play a critical role in protecting against hypoxemia, and their activation increases sympathetic activity, arterial pressure, and ventilation, responses opposed by acute stimulation of the baroreflex. Although chemoreceptor hypersensitivity is associated with sympathetically mediated hypertension, the mechanisms involved and their significance in the pathogenesis of hypertension remain unclear. We investigated the chronic interactions of these reflexes in dogs with sympathetically mediated, obesity-induced hypertension based on the hypothesis that hypoxemia and tonic activation of carotid chemoreceptors may be associated with obesity. After 5 weeks on a high-fat diet, the animals experienced a 35% to 40% weight gain and increases in arterial pressure from 106±3 to 123±3 mm Hg and respiratory rate from 8±1 to 12±1 breaths/min along with hypoxemia (arterial partial pressure of oxygen=81±3 mm Hg) but eucapnia. During 7 days of carotid baroreflex activation by electric stimulation of the carotid sinus, tachypnea was attenuated, and hypertension was abolished before these variables returned to prestimulation values during a recovery period. After subsequent denervation of the carotid sinus region, respiratory rate decreased transiently in association with further sustained reductions in arterial partial pressure of oxygen (to 65±2 mm Hg) and substantial hypercapnia. Moreover, the severity of hypertension was attenuated from 125±2 to 116±3 mm Hg (45%-50% reduction). These findings suggest that hypoxemia may account for sustained stimulation of peripheral chemoreceptors in obesity and that this activation leads to compensatory increases in ventilation and central sympathetic outflow that contributes to neurogenically mediated hypertension. Furthermore, the excitatory effects of chemoreceptor hyperactivity are abolished by chronic activation of the carotid baroreflex. © 2016 American Heart Association, Inc.

Infectious arteritis of the internal carotid artery complicating retropharyngeal abscess.

PubMed

Lisan, Q; Tran, H; Verillaud, B; Herman, P

2016-02-01

Retropharyngeal abscess is a well-known entity in children, but can also occur in adults. The two main vascular complications are vascular compression and pseudoaneurysm, while infectious arteritis of the internal carotid artery is exceptional. The authors describe a case of a retropharyngeal abscess in an adult woman complicated by infectious arteritis of the internal carotid artery. This rare complication was treated by endovascular occlusion of the internal carotid artery and incision and drainage of the abscess in combination with antibiotic and anticoagulant therapy. The patient did not present any neurological sequelae and follow-up MRI did not reveal any signs of vascular or neurological complications. This case highlights the importance of thorough examination of imaging performed in the context of deep neck space abscess to detect signs of vascular involvement. Treatment must be aggressive in view of the life-threatening risk of arterial rupture or septic embolism. This is the first reported case of infectious arteritis involving the internal carotid artery complicating retropharyngeal abscess. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

A historical prospective cohort study of carotid artery stenosis after radiotherapy for head and neck malignancies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Paul D.; Foote, Robert L.; McLaughlin, Mark P.

2005-12-01

Purpose: To determine carotid artery stenosis incidence after radiotherapy for head-and-neck neoplasms. Methods and Materials: This historical prospective cohort study comprised 44 head-and-neck cancer survivors who received unilateral neck radiotherapy between 1974 and 1999. They underwent bilateral carotid duplex ultrasonography to detect carotid artery stenosis. Results: The incidence of significant carotid stenosis (8 of 44 [18%]) in the irradiated neck was higher than that in the contralateral unirradiated neck (3 of 44 [7%]), although this difference was not statistically significant (p = 0.13). The rate of significant carotid stenosis events increased as the time after radiotherapy increased. The risk ofmore » ipsilateral carotid artery stenosis was higher in patients who had undergone a neck dissection vs. those who had not. Patients with significant ipsilateral stenosis also tended to be older than those without significant stenosis. No other patient or treatment variables correlated with risk of carotid artery stenosis. Conclusions: For long-term survivors after neck dissection and irradiation, especially those who are symptomatic, ultrasonographic carotid artery screening should be considered.« less

[Carotid Stenting in France after the EVA 3S and SPACE publications].

PubMed

Beyssen, B; Rousseau, H; Bracard, S; Sapoval, M; Gaux, J-C

2007-01-01

Angioplasty of stenoses of the carotid bifurcation is a revascularization procedure that is used successfully in many patients. With more than 10 years of experience now, the feasibility of carotid stenting has been demonstrated. Its distribution is highly variable depending on the country, with a mean penetration rate in Europe of 15% of the number of carotid revascularizations. However, the complication rate is highly variable from one series to another and depends on the type of patient treated and the operator's learning curve. The results of the first two randomized studies comparing endarterectomy and carotid stenting, EVA 3S in France and SPACE in Germany, have just been published. The conclusions of these studies only relate to symptomatic patients, who make up a small proportion of revascularized patients. At 30 days, the French study concluded that surgery was better, and the German study showed no advantage to stenting. The analysis of these results compared to other publications should make it possible to best define the current indications for carotid stenting.

Evidence for a carotid body homolog in the lizard Tupinambis merianae.

PubMed

Reichert, Michelle N; Brink, Deidre L; Milsom, William K

2015-01-15

The homolog to the mammalian carotid body has not yet been identified in lizards. Observational studies and evolutionary history provide indirect evidence for the existence of a chemoreceptor population at the first major bifurcation of the common carotid artery in lizards, but a chemoreceptive role for this area has not yet been definitively demonstrated. We explored this possibility by measuring changes in cardiorespiratory variables in response to focal arterial injections of the hypoxia mimic sodium cyanide (NaCN) into the carotid artery of 12 unanesthetized specimens of Tupinambis merianae. These injections elicited increases in heart rate (f(H); 101±35% increase) and respiratory rate (f(R); 620±119% increase), but not mean arterial blood pressure (MAP). These responses were eliminated by vagal denervation. Similar responses were elicited by injections of the neurotransmitters acetylcholine (ACh) and serotonin (5-HT) but not norepinephrine. Heart rate and respiratory rate increases in response to NaCN could be blocked or reduced by antagonists to ACh (atropine) and/or 5-HT (methysergide). Finally, using immunohistochemistry, we demonstrate the presence of putative chemoreceptive cells immunopositive for the cholinergic cell marker vesicular ACh transporter (VAChT) and 5-HT on internal lattice-like structures at the carotid bifurcation. These results provide evidence in lizards for the existence of dispersed chemoreceptor cells at the first carotid bifurcation in the central cardiovascular area that have similar properties to known carotid body homologs, adding to the picture of chemoreceptor evolution in vertebrates. © 2015. Published by The Company of Biologists Ltd.

Role of substance P in neutral endopeptidase modulation of hypoxic response of the carotid body.

PubMed

Kumar, G K; Yu, R K; Overholt, J L; Prabhakar, N R

2000-01-01

Carotid body expresses neutral endopeptidase (NEP)-like enzyme activity and phosphoramidon, an inhibitor of NEP augments sensory response of the carotid body to hypoxia (Kumar et al., 1990). NEP hydrolyzes substance P (SP) and methionine enkephalin (Met-ENK) in the nervous system. In the present study, we determined whether NEP hydrolyzes Met-ENK and SP in the carotid body and whether these peptides contribute to the phosphoramidon-induced potentiation of the sensory response to hypoxia. Experiments were performed on carotid bodies excised from anaesthetized adult cats. HPLC analysis showed that both SP and Met-ENK were hydrolyzed by the carotid body. Phosphoramidon (400 microM) markedly inhibited SP (approximately 90%) but had only marginal effect on Met-ENK hydrolysis (approximately 15%). Sensory responses of the carotid body in vitro to hypoxia (pO2, 68 +/- 6 mmHg) and SP (10 nmoles) were potentiated by phosphoramidon by approximately 80% and approximately 275% respectively (p < 0.01). SP-receptor antagonist abolished phosphoramidon-induced potentiation of the sensory response to hypoxia as well as to SP. These results demonstrate that SP is a preferred substrate for NEP in the carotid body and SP plays a major role in the potentiation of the hypoxic response of the carotid body by phosphoramidon.

Polymorphisms of apolipoprotein E and angiotensin-converting enzyme genes and carotid atherosclerosis in heavy drinkers.

PubMed

Bednarska-Makaruk, Małgorzata; Rodo, Maria; Markuszewski, Cezary; Rozenfeld, Anna; Swiderska, Malgorzata; Habrat, Bogusław; Wehr, Hanna

2005-01-01

To investigate the influence of apolipoprotein E (APOE) and angiotensin-converting enzyme (ACE) gene polymorphisms on carotid artery atherosclerosis in alcoholism. Polymorphism of both genes was identified by DNA analysis in 130 male alcohol-dependent patients. Intima-media thickness (IMT) was measured ultrasonographically. Multivariate regression analysis showed that of all the known risk factors the greatest impact on carotid atherosclerosis in alcoholics was exerted by age, hypertension, LDL cholesterol and fasting plasma glucose levels. Subjects carrying the APO E epsilon4 allele were more liable to develop atherosclerotic changes in carotid arteries compared with subjects with the epsilon3/3 genotype, which showed statistical significance in patients under 50 years of age. No association was shown between ACE I/D polymorphism and carotid atherosclerosis. APO E polymorphism can increase the risk of carotid atherosclerosis development in an alcoholic subject. The association of the APO E epsilon4 allele with carotid atherosclerosis was significant in younger patients. Since the elevated carotid IMT is considered to be a good marker of increased risk of generalized atherosclerosis the consequences could involve both cardiac and cerebrovascular events.

Association between Carotid Artery Stenosis and Cognitive Impairment in Stroke Patients: A Cross-Sectional Study

PubMed Central

Zhu, Runxiu; Yan, Zhongrui; Zheng, Shouhuan; Wang, Jingwei; Huo, Jia; Liu, Yunlin; Li, Xin; Ji, Yong

2016-01-01

To investigate potential associations between carotid artery stenosis and cognitive impairment among patients with acute ischemic stroke and to provide important clinical implications. We measured the degree of carotid artery stenosis and recorded the Mini-Mental State Examination score (MMSE) at admission in 3116 acute ischemic stroke patients. The association between carotid stenosis and cognitive impairment assessed by MMSE was tested using multivariate regression analysis. Other clinical variables of interest were also studied. After adjusting for age, gender, education level, marriage, alcohol use, tobacco use, physical activity, hypertension, diabetes, hypercholesterolemia, atrial fibrillation, myocardial infarction and NIHSS (National Institutes of Health Stroke Scale) score, we found that participants with high-grade stenosis of the carotid artery had a higher likelihood of cognitive impairment compared to those without carotid artery stenosis (OR = 1.49, 95%CI: 1.05–2.11, p<0.001). Left common carotid artery stenosis was associated with cognitive impairment in the univariate analysis, although this effect did not persist after adjustment for the NIHSS score. Cognitive impairment was associated with high-grade stenosis of the right carotid artery. PMID:26751070

Carotid stenosis assessment with multi-detector CT angiography: comparison between manual and automatic segmentation methods.

PubMed

Zhu, Chengcheng; Patterson, Andrew J; Thomas, Owen M; Sadat, Umar; Graves, Martin J; Gillard, Jonathan H

2013-04-01

Luminal stenosis is used for selecting the optimal management strategy for patients with carotid artery disease. The aim of this study is to evaluate the reproducibility of carotid stenosis quantification using manual and automated segmentation methods using submillimeter through-plane resolution Multi-Detector CT angiography (MDCTA). 35 patients having carotid artery disease with >30 % luminal stenosis as identified by carotid duplex imaging underwent contrast enhanced MDCTA. Two experienced CT readers quantified carotid stenosis from axial source images, reconstructed maximum intensity projection (MIP) and 3D-carotid geometry which was automatically segmented by an open-source toolkit (Vascular Modelling Toolkit, VMTK) using NASCET criteria. Good agreement among the measurement using axial images, MIP and automatic segmentation was observed. Automatic segmentation methods show better inter-observer agreement between the readers (intra-class correlation coefficient (ICC): 0.99 for diameter stenosis measurement) than manual measurement of axial (ICC = 0.82) and MIP (ICC = 0.86) images. Carotid stenosis quantification using an automatic segmentation method has higher reproducibility compared with manual methods.

Evaluation of carotid stenosis with axial high-resolution black-blood MR imaging.

PubMed

U-King-Im, Jean M; Trivedi, Rikin A; Sala, Evis; Graves, Martin J; Gaskarth, Mathew; Higgins, Nicholas J; Cross, Justin C; Hollingworth, William; Coulden, Richard A; Kirkpatrick, Peter J; Antoun, Nagui M; Gillard, Jonathan H

2004-07-01

High-resolution axial black-blood MR imaging (BB MRI) has been shown to be able to characterise carotid plaque morphology. The aim of this study was to explore the accuracy of this technique in quantifying the severity of carotid stenosis. A prospective study of 54 patients with symptomatic carotid disease was conducted, comparing BB MRI to the gold standard, conventional digital subtraction X-ray angiography (DSA). The BB MRI sequence was a fast-spin echo acquisition (TE = 42 ms, ETL = 24, field of view = 100 x 100 mm, slice thickness = 3.0 mm) at 1.5 T using a custom-built phased-array coil. Linear measurements of luminal and outer carotid wall diameter were made directly from the axial BB MRI slices by three independent blinded readers and stenosis was calculated according to European Carotid Surgery Trial (ECST) criteria. There was good agreement between BB MRI and DSA (intraclass correlation = 0.83). Inter-observer agreement was good (average kappa = 0.77). BB MRI was accurate for detection of severe stenosis (> or = 80%) with sensitivity and specificity of 87 and 81%, respectively. Eight cases of "DSA-defined" moderate stenosis were overestimated as severe by BB MRI and this may be related to non-circular lumens. Axial imaging with BB MRI could potentially be used to provide useful information about severity of carotid stenosis. Copyright 2004 Springer-Verlag

There is no benefit to universal carotid artery duplex screening before a major cardiac surgical procedure.

PubMed

Adams, Brian C; Clark, Ross M; Paap, Christina; Goff, James M

2014-01-01

Perioperative stroke is a devastating complication after cardiac surgery. In an attempt to minimize this complication, many cardiac surgeons routinely preoperatively order carotid artery duplex scans to assess for significant carotid stenosis. We hypothesize that the routine screening of preoperative cardiac surgery patients with carotid artery duplex scans detects few patients who would benefit from carotid intervention or that a significant carotid stenosis reliably predicts stroke risk after cardiac surgery. A retrospective review identified 1,499 patients who underwent cardiac surgical procedures between July 1999 and September 2010. Data collected included patient demographics, comorbidities, history of previous stroke, preoperative carotid artery duplex scan results, location of postoperative stroke, and details of carotid endarterectomy (CEA) procedures before, in conjunction with, or after cardiac surgery. Statistical methods included univariate analysis and Fisher's exact test. Twenty-six perioperative strokes were identified (1.7%). In the 21 postoperative stroke patients for whom there is complete carotid artery duplex scan data, 3 patients had a hemodynamically significant lesion (>70%) and 1 patient underwent unilateral carotid CEA for bilateral disease. Postoperative strokes occurred in the anterior cerebral circulation (69.2%), posterior cerebral circulation (15.4%), or both (15.4%). Patient comorbidities, preoperative carotid artery duplex scan screening velocities, or types of cardiac surgical procedure were not predictive for stroke. Thirteen patients (0.86%) underwent CEA before, in conjunction with, or after cardiac surgery. Two of these patients had symptomatic disease, 1 of whom underwent CEA before and the other after his cardiac surgery. Of the 11 asymptomatic patients, 2 underwent CEA before, 3 concurrently, and 6 after cardiac surgery. Left main disease (≥50% stenosis), previous stroke, and peripheral vascular disease were found to be

Effects of droperidol on activity of carotid body chemoreceptors in cat.

PubMed Central

Aminoff, M J; Jaffe, R A; Sampson, S R; Vidruk, E H

1978-01-01

1 The effect of droperidol on the spontaneous activity of carotid body chemoreceptors and on their response to various stimuli was studied in 21 anaesthetized, paralyzed and artificially ventilated cats. Carotid body blood flow was controlled with a perfusion pump, and drugs were injected into the perfusion circuit. 2 In low doses, droperidol transiently increased the rate of spontaneous chemoreceptor activity, but in higher doses it depressed chemoreceptor activity after an initial stimulation. 3 Droperidol reduced or abolished the normal increase in chemoreceptor activity produced by stagnant asphyxia. This effect did not depend solely on the ability of droperidol to suppress spontaneously occurring impulses. Chemoreceptor responses to sodium cyanide, and to dopamine were also inhibited. 4 Dopamine antagonists other than droperidol were also studied for their effect on chemocreceptor activity. Chlorpromazine depressed spontaneous chemoreceptor activity and also reduced the chemoreceptor responses to sodium cyanide and dopamine, as did pimozide. The effects of these dopamine antagonists were much briefer and less marked than those of droperiodol. 5 Although the influence that we have shown droperidol to have on peripheral chemoreceptor activity has an uncertain basis, it may have important implications in human and veterinary medicine. PMID:667417

Cerebral hematocrit decreases with hemodynamic compromise in carotid artery occlusion: a PET study.

PubMed

Yamauchi, H; Fukuyama, H; Nagahama, Y; Katsumi, Y; Okazawa, H

1998-01-01

This study investigated whether in patients with internal carotid artery occlusion the regional cerebral hematocrit correlates with cerebral hemodynamics or metabolic state and, if so, how the regional cerebral hematocrit changes in the hemodynamically compromised region. We used positron emission tomography to study seven patients with unilateral internal carotid artery occlusion and no cortical infarction in the chronic stage. The distributions of red blood cell and plasma volumes were assessed using oxygen-15-labeled carbon monoxide and copper-62-labeled human serum albumin-dithiosemicarbazone tracers, respectively. The calculated hematocrit value was compared with the hemodynamic and metabolic parameters measured with the oxygen-15 steady-state technique. In the cerebral cortex, the value of the cerebral hematocrit varied but was correlated with the hemodynamic and metabolic status. Stepwise regression analysis revealed that the large vessel hematocrit, the cerebral metabolic rate of oxygen, and the cerebral blood flow or the oxygen extraction fraction accounted for a significant proportion of variance of the cerebral hematocrit. The oxygen extraction fraction and the cerebral metabolic rate of oxygen negatively correlated with the cerebral hematocrit, whereas the cerebral blood flow correlated positively: patients with reduced blood supply relative to metabolic demand (decreased blood flow with increased oxygen extraction fraction) showed low hematocrit values. In carotid artery occlusion in the chronic stage, regional cerebral hematocrit may vary according to cerebral hemodynamics and metabolic status. Regional cerebral hematocrit may decrease with hemodynamic compromise unless oxygen metabolism concomitantly decreases.

Prevalence of extracranial carotid artery aneurysms in patients with an intracranial aneurysm.

PubMed

Pourier, V E C; van Laarhoven, C J H C M; Vergouwen, M D I; Rinkel, G J E; de Borst, Gert J

2017-01-01

Aneurysms in various arterial beds have common risk- and genetic factors. Data on the correlation of extracranial carotid artery aneurysms (ECAA) with aneurysms in other vascular territories are lacking. We aimed to investigate the prevalence of ECAA in patients with an intracranial aneurysm (IA). We used prospectively collected databases of consecutive patients registered at the University Medical Center Utrecht with an unruptured intracranial aneurysm (UIA) or aneurysmal Subarachnoid hemorrhage (SAH). The medical files of patients included in both databases were screened for availability of radiological reports, imaging of the brain and of the cervical carotid arteries. All available radiological images were then reviewed primarily for the presence of an ECAA and secondarily for an extradural/cavernous carotid or vertebral artery aneurysm. An ECAA was defined as a fusiform dilation ≥150% of the normal internal or common carotid artery or a saccular distention of any size. We screened 4465 patient records (SAH database n = 3416, UIA database n = 1049), of which 2931 had radiological images of the carotid arteries available. An ECAA was identified in 12/638 patients (1.9%; 95% CI 1.1-3.3) with completely imaged carotid arteries and in 15/2293 patients (0.7%; 95% CI 0.4-1.1) with partially depicted carotid arteries. Seven out of 27 patients had an additional extradural (cavernous or vertebral artery) aneurysm. This comprehensive study suggests a prevalence for ECAA of approximately 2% of patients with an IA. The rarity of the disease makes screening unnecessary so far. Future registry studies should study the factors associated with IA and ECAA to estimate the prevalence of ECAA in these young patients more accurately.

Intima-Media Thickness in the Carotid and Femoral Arteries for Detection of Arteriosclerosis in Human Immunodeficiency Virus-Positive Individuals.

PubMed

Godoi, Emmanuelle Tenório Albuquerque Madruga; Brandt, Carlos Teixeira; Lacerda, Heloisa Ramos; Godoi, Jocelene Tenório Albuquerque Madruga; Oliveira, Dinaldo Cavalcanti de; Costa, Gabriela Farias Araujo Sousa; Santos Junior, Gerson Gomes Dos; Leite, Kaliene Maria Estevão; Godoi, Juannicelle Tenório Albuquerque Madruga; Vasconcelos, Adriana Ferraz de

2017-01-01

The prevalence of atherosclerosis is higher in HIV-positive people, who also experience it earlier than the general population. To assess and compare the prevalence of atherosclerosis evaluated by the intima-media thickness of carotid and femoral arteries, and by the ankle-brachial pressure index (ABPI) in HIV patients treated or not treated with protease inhibitors (PIs) and controls. Eighty HIV+ subjects (40 using PIs and 40 not using PIs) and 65 controls were included in the study. Atherosclerosis was diagnosed by (carotid and femoral) ITM measurement and ABPI. Classical risk factors for atherosclerosis and HIV were compared between the groups by statistical tests. A p ≤ 0.05 was considered significant. An IMT > P75 or the presence of plaque was higher in the HIV+ than in the control group (37.5% vs 19%, p = 0.04). Comparative analysis showed a significant difference (p=0.014) in carotid IMT between HIV+ with PIs (0.71 ± 0.28 mm), without PIs 0.63 ± 0.11 mm and, and controls (0.59 ± 0.11 mm). There was no significant difference in femoral IMT between the groups or in ABPI between HIV+ subjects and controls. However, a significant difference (p=0.015) was found between HIV+ patients not treated with PIs (1.17 [1.08 - 1.23]), and controls 1.08 [1.07 - 1.17]). In HIV patients, atherosclerosis is more prevalent and seems to occur earlier with particular characteristics compared with HIV-negative subjects.

Optimizing protocols for risk prediction in asymptomatic carotid stenosis using embolic signal detection: the Asymptomatic Carotid Emboli Study.

PubMed

King, Alice; Shipley, Martin; Markus, Hugh

2011-10-01

Improved methods are required to identify patients with asymptomatic carotid stenosis at high risk for stroke. The Asymptomatic Carotid Emboli Study recently showed embolic signals (ES) detected by transcranial Doppler on 2 recordings that lasted 1-hour independently predict 2-year stroke risk. ES detection is time-consuming, and whether similar predictive information could be obtained from simpler recording protocols is unknown. In a predefined secondary analysis of Asymptomatic Carotid Emboli Study, we looked at the temporal variation of ES. We determined the predictive yield associated with different recording protocols and with the use of a higher threshold to indicate increased risk (≥2 ES). To compare the different recording protocols, sensitivity and specificity analyses were performed using analysis of receiver-operator characteristic curves. Of 477 patients, 467 had baseline recordings adequate for analysis; 77 of these had ES on 1 or both of the 2 recordings. ES status on the 2 recordings was significantly associated (P<0.0001), but there was poor agreement between ES positivity on the 2 recordings (κ=0.266). For the primary outcome of ipsilateral stroke or transient ischemic attack, the use of 2 baseline recordings lasting 1 hour had greater predictive accuracy than either the first baseline recording alone (P=0.0005), a single 30-minute (P<0.0001) recording, or 2 recordings lasting 30 minutes (P<0.0001). For the outcome of ipsilateral stroke alone, two recordings lasting 1 hour had greater predictive accuracy when compared to all other recording protocols (all P<0.0001). Our analysis demonstrates the relative predictive yield of different recording protocols that can be used in application of the technique in clinical practice. Two baseline recordings lasting 1 hour as used in Asymptomatic Carotid Emboli Study gave the best risk prediction.

Double balloon protection during carotid artery stenting for vulnerable carotid stenosis reduces the incidence of new brain lesions.

PubMed

Nakazaki, Masahito; Nonaka, Tadashi; Takahashi, Akira; Yonemasu, Yasuyuki; Nomura, Tatsufumi; Onda, Toshiyuki; Honda, Osamu; Hashimoto, Yuji; Ohnishi, Hirofumi; Sasaki, Masanori; Daibo, Masahiko; Honmou, Osamu

2016-07-01

The use of distal filter protection alone is associated with a high risk of ischemic complications when vulnerable carotid stenosis is treated by carotid artery stenting (CAS). Double balloon protection, a combination of distal balloon protection and proximal balloon occlusion, can be utilized. We assessed the outcome and complications of the double balloon protection method for vulnerable carotid stenosis. Among 130 patients who underwent CAS from 2009 to 2014, we enrolled the following patients: those whose target lesion was vulnerable as evaluated by MRI, i.e., a signal ratio of plaque to posterior cervical muscle on T1-weighted images before CAS of ≥1.5, and those who underwent diffusion-weighted imaging (DWI) studies within 48 h after the procedure. Ninety patients were enrolled. We investigated DWI findings of the double balloon protection group compared with those of the simple distal balloon protection and distal filter protection groups. Sixty-four patients (71 %) underwent double balloon protection, 15 patients (17 %) simple distal balloon protection, and 11 patients (12 %) distal filter protection. Symptomatic embolic complications and new lesions on DWI after CAS were significantly less common in patients undergoing double balloon protection compared to distal balloon protection or distal filter protection (0 % vs. 20 %, 9 %, P < 0.01, and 30 % vs. 67 %, 82 %, P < 0.01, respectively). Logistic regression analysis also identified the odds ratio of double balloon protection for new lesions on DWI after CAS of 0.23 (95 % confidence interval: 0.07-0.70, P < 0.01) compared to simple distal protections. In the patients who underwent CAS for vulnerable carotid stenosis, double balloon protection was an independent significant factor associated with a reduction in the risk of new lesions on DWI after the procedure compared to conventional distal protections.

Carotid body size measured by computed tomographic angiography in individuals born prematurely.

PubMed

Bates, Melissa L; Welch, Brian T; Randall, Jess T; Petersen-Jones, Humphrey G; Limberg, Jacqueline K

2018-05-24

We tested the hypothesis that the carotid bodies would be smaller in individuals born prematurely or exposed to perinatal oxygen therapy when compared individuals born full term that did not receive oxygen therapy. A retrospective chart review was conducted on patients who underwent head/neck computed tomography angiography (CTA) at the Mayo Clinic between 10 and 40 years of age (n = 2503). Patients were identified as premature ( < 38 weeks) or receiving perinatal oxygen therapy by physician completion or billing codes (n = 16 premature and n = 7 receiving oxygen). Widest axial measurements of the carotid body images captured during the CTA were performed. Carotid body visualization was possible in 43% of patients and 52% of age, sex, and body mass index (BMI)-matched controls but only 17% of juvenile preterm subjects (p = 0.07). Of the carotid bodies that could be visualized, widest axial measurements of the carotid bodies in individuals born prematurely (n = 7, 34 ± 4 weeks gestation, birth weight: 2460 ± 454 g; average size: 2.5 ± 0.2 cm) or individuals exposed to perinatal oxygen therapy (n = 3, 38 ± 2 weeks gestation, Average size: 2.2 ± 0.1 cm) were not different when compared to controls (2.3 ± 0.2 cm and 2.3 ± 0.2 cm, respectively, p > 0.05). Carotid body size, as measured using CTA, is not smaller in adults born prematurely or exposed to perinatal oxygen therapy when compared to sex, age, and BMI-matched controls. However, carotid body visualization was lower in juvenile premature patients. The decreased ability to visualize the carotid bodies in these individuals may be a result of their prematurity. Copyright © 2018. Published by Elsevier B.V.

COMPLETENESS OF CIRCLE OF WILLIS IN ASYMPTOMATIC AND SYMPTOMATIC EXTRACRANIAL CAROTID DISEASE.

PubMed

Manojlovic, Vladimir; Popovic, Vlandan; Nikoloc, Dragan; Milosevic, Dorde; Pasternak, Janko; Budakov, Nebojsa

2016-11-01

This research has been aimed at determining whether incomplete Circle of Willis in patients with significant extracranial carotid stenosis is associated with a higher incidence of neurological symptomatology and/or ischemnic cerebral lesions. The research was conducted as a prospective study which comprised 211 patients who underwent surgical treatment of extracranial carotid disease at the Department of Vascular Surgery in Novi Sad and 102 patients in the control group. Each patient underwent preoperative magnetic resonance imaging and magnetic resonance angiography with visualization of cerebral parenchyma. extracranial and intracranial cerebral circulation. Assessment of Circle of Willis morphology was performed by 3D time-of-fight magnetic resonance angiogram sequence analysis. The patients were divided into two groups: group I - the patients with'complete Circle of Willis and group II - the patients with incomplete Circle of Willis i.e. with the disruption of anterior and/ or ipsilateral posterior circulation - regarding the side of signif icant carotid stenosis. Out of 211 patients who -were operated during a two-year period, 133 had the complete Circle of Willis. while 78 patients had the incomplete Circle of Willis. Out of 111 patients with symptomatic carotid disease or silent cerebral infarction, 52.5% (58) had the complete Circle of' Willis and 47.5% (53) had the incomplete Circle of Willis. It was shown to be statistically different (P = 0.0146) in relation with the asymptomatic group of patients (100), where the frequency of the complete Circle of Willis was 75% (75) while the insufficiency of anterior or ipsilateral posterior collateral ization was found in 25% (25). In the control group there were significantly fewer cases of developed collateral flow and the complete Circle of Willis (41%) compared to the operated patients with extracranial carotid stenosis (63%) (P= 0.0003). Incompleteness of Circle of Willis is associated with more frequent

Early improvement in carotid plaque echogenicity by acarbose in patients with acute coronary syndromes.

PubMed

Hirano, Mitsumasa; Nakamura, Takamitsu; Obata, Jyun-ei; Fujioka, Daisuke; Saito, Yukio; Kawabata, Ken-ichi; Watanabe, Kazuhiro; Watanabe, Yosuke; Kugiyama, Kiyotaka

2012-01-01

The resolution of hyperglycemia is associated with suppression of in-hospital cardiac complications in patients with acute coronary syndromes (ACS). This study evaluated carotid artery plaque echolucency using ultrasound in patients with ACS and type 2 diabetes mellitus (DM) to determine whether acarbose, an α-glucosidase inhibitor, may rapidly stabilize unstable atherosclerotic plaques. ACS patients with type 2 DM and carotid plaques (n=44) were randomly assigned to treatment with acarbose (150 or 300 mg/day, n=22) or a control group (no acarbose, n=22). Acarbose treatment was initiated within 5 days after the onset of ACS. Unstable carotid plaques were assessed by measuring plaque echolucency using carotid ultrasound with integrated backscatter (IBS) before, and at 2 weeks, 1 and 6 months after the initiation of treatment. An increase in the IBS value reflected an increase in carotid plaque echogenicity. As results, the IBS value of echolucent carotid plaques showed a significant increase at 1 month and a further increase at 6 months after treatment in the acarbose group, but there was minimal change in the control group. The increase in IBS values was significantly correlated with a decrease in C-reactive protein levels. Acarbose rapidly improved carotid plaque echolucency within 1 month of therapy in patients with ACS and type 2 DM.

Three-dimensional ultrasound-based texture analysis of the effect of atorvastatin on carotid atherosclerosis

NASA Astrophysics Data System (ADS)

Awad, Joseph; Krasinski, Adam; Spence, David; Parraga, Grace; Fenster, Aaron

2010-03-01

Carotid atherosclerosis is the major cause of ischemic stroke, a leading cause of death and disability. This is driving the development of image analysis methods to quantitatively evaluate local arterial effects of potential treatments of carotid disease. Here we investigate the use of novel texture analysis tools to detect potential changes in the carotid arteries after statin therapy. Three-dimensional (3D) carotid ultrasound images were acquired from the left and right carotid arteries of 35 subjects (16 treated with 80 mg atorvastatin and 19 treated with placebo) at baseline and after 3 months of treatment. Two-hundred and seventy texture features were extracted from 3D ultrasound carotid artery images. These images previously had their vessel walls (VW) manually segmented. Highly ranked individual texture features were selected and compared to the VW volume (VWV) change using 3 measures: distance between classes, Wilcoxon rank sum test, and accuracy of the classifiers. Six classifiers were used. Using texture feature (L7R7) increases the average accuracy and area under the ROC curve to 74.4% and 0.72 respectively compared to 57.2% and 0.61 using VWV change. Thus, the results demonstrate that texture features are more sensitive in detecting drug effects on the carotid vessel wall than VWV change.

Carotid artery wall shear stress is independently correlated with renal function in the elderly.

PubMed

Guo, Yuqi; Wei, Fang; Wang, Juan; Zhao, Yingxin; Sun, Shangwen; Zhang, Hua; Liu, Zhendong

2018-01-12

Hemodynamic has increasingly been regarded as an important factor of renal function. However, the relationship between carotid artery wall shear stress (WSS) and renal function is not clarified. To investigate the relationship between carotid WSS and renal function, we recruited 761 older subjects aged 60 years and over from community-dwelling in the Shandong area, China. Carotid WSS, endothelial function, and estimated glomerular filtration rate (eGFR) were assessed in all subjects. Subjects were grouped by the interquartile of the carotid artery mean WSS. We found that the eGFRs derived from serum creatinine and/or cystatin C using three CKD-EPI equations were significantly higher and albumin/creatinine ratio was lower in the higher interquartile groups than in the lower interquartile groups ( P <0.05). The mean WSS was independently correlated with eGFRs even after adjustment for confounders. Similar findings were found between carotid artery peak WSS and eGFRs and albumin/creatinine ratio. In addition, we found that endothelial function was strongly related to carotid WSS and renal function after adjustment for confounders. In conclusion, there is an independent correlation of carotid WSS with renal function in the elderly. The local rheologic forces may play an important role in renal function changing. The correlation may be mediated by regulation of endothelial function.

Prevalence of Use of Human Milk in US Advanced Care Neonatal Units

PubMed Central

Scanlon, Kelley S.

2013-01-01

BACKGROUND AND OBJECTIVE: The American Academy of Pediatrics recommends all preterm infants receive human milk. The objective of this study was to describe the use of human milk in advanced care neonatal units of US maternity hospitals. METHODS: We used Centers for Disease Control and Prevention’s national Maternity Practices in Infant Nutrition and Care survey from 2007, 2009, and 2011 to analyze 2 questions to describe the prevalence of US advanced care (special/level 2 or intensive/level 3) neonatal units routinely providing human milk to infants, and the use of any donor milk in these units. RESULTS: In 2011, 30.8% of maternity hospitals reported that most infants (≥90%) were routinely provided human milk in advanced care units, compared with 26.7% in 2009 and 21.2% in 2007 (trend P < .001). States in the Northwest and Northeast had a higher prevalence of hospitals routinely providing human milk to ≥90% of infants in advanced care units. In 2011, 22.0% of maternity hospitals providing advanced care used banked donor milk, compared with 14.4% in 2009 and 11.5% in 2007 (trend P < .001). Most of this increase occurred in intensive care units (25.1% 2007 vs 45.2% 2011; trend P < .001). There was substantial geographic variation in the prevalence of advanced care units using donor milk; generally the prevalence was higher in the West and in states with a milk bank in the state or a neighboring state. CONCLUSIONS: The use of human milk in US advanced care neonatal units is increasing; however, only one-third of these units are routinely providing human milk to most infants. PMID:23669517

Arterial function of carotid and brachial arteries in postmenopausal vegetarians.

PubMed

Su, Ta-Chen; Torng, Pao-Ling; Jeng, Jiann-Shing; Chen, Ming-Fong; Liau, Chiau-Suong

2011-01-01

Vegetarianism is associated with a lower risk of cardiovascular disease. However, studies of arterial function in vegetarians are limited. This study investigated arterial function in vegetarianism by comparing 49 healthy postmenopausal vegetarians with 41 age-matched omnivores. The arterial function of the common carotid artery was assessed by carotid duplex, while the pulse dynamics method was used to measure brachial artery distensibility (BAD), compliance (BAC), and resistance (BAR). Fasting blood levels of glucose, lipids, lipoprotein (a), high-sensitivity C-reactive protein, homocysteine, and vitamin B12 were also measured. Vegetarians had significantly lower serum cholesterol, high-density and low-density lipoprotein, and glucose compared with omnivores. They also had lower vitamin B12 but higher homocysteine levels. Serum levels of lipoprotein (a) and high-sensitivity C-reactive protein were no different between the two groups. There were no significant differences in carotid beta stiffness index, BAC, and BAD between the two groups even after adjustment for associated covariates. However, BAR was significantly lower in vegetarians than in omnivores. Multiple linear regression analysis revealed that age and pulse pressure were two important determinants of carotid beta stiffness index and BAD. Vegetarianism is not associated with better arterial elasticity. Apparently healthy postmenopausal vegetarians are not significantly better in terms of carotid beta stiffness index, BAC, and BAD, but have significantly decreased BAR than omnivores. Prevention of vitamin B12 deficiency might be beneficial for cardiovascular health in vegetarians.

[Effects of carotid endarterectomy on cognitive function in patients with carotid stenosis].

PubMed

Wang, Qi; Zhang, Ming; Huang, Dian; Zhou, Yu; Qiao, Tong

2014-08-01

To investigate the theraputic effects of carotid endarterectomy (CEA) on cognitive function in patients with carotid stenosis (CAS) and congnitive impairment. CEA was performed on 38 patients with CAS from December 2011 to July 2013. There were 26 male and 12 female patients, with an average age of (70 ± 7) years. Patients was underwent neuropsychological examinations (NPEs) including Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) at 1 week before and 6 weeks after treatment. Cerebral perfusion was assessed with MR perfusion-weighted imaging and diffusion-weighted inmaging at 1 week before and 6 weeks after treatment. All of the 38 patients completed NPEs and MRI at baseline and 6 weeks after CEA. After therapy, the parameters and the extents of abnormal perfusion was improved, including the decrease of time to peak (29 ± 9 vs. 23 ± 4), relative mean transit time (22 ± 8 vs. 14 ± 6), arrive time (21 ± 8 vs. 15 ± 4) and relative cerebral blood volume (11.6 ± 3.5 vs. 7.5 ± 3.2) (t = 1.31 to 5.24, all P < 0.05). Significant improvement in MoCA (20.4 ± 1.5 vs. 22.0 ± 1.6, t = -4.25, P = 0.000) but MMSE (26.16 ± 1.35 vs. 26.47 ± 1.52, t = -0.96, P = 0.341) was observed. CEA significantly improved the assessment of visuospacial/constructive abilities (2.4 ± 0.9 vs. 2.8 ± 0.7), naming (2.0 ± 0.7 vs. 2.3 ± 0.6), abstraction (1.2 ± 0.7 vs. 1.6 ± 0.6) and attention (2.3 ± 0.6 vs. 2.6 ± 0.5) (t = 0.015 to 0.029, P = 0.015). CEA can improve the cognitive function of patients with carotid stenosis as well as the cerebral perfusion of patients and has therapeutic effects on vascular mild cognitive impairment.

Usefulness of automatic measurement of contrast flow intensity: an innovative tool in contrast-enhanced ultrasound imaging of atherosclerotic carotid plaque neovascularization. A pilot study.

PubMed

Lisowska, A; Knapp, M; Tycinska, A; Sawicki, R; Kralisz, P; Lisowski, P; Sobkowicz, B; Musial, W I

2014-02-01

Contrast-enhanced ultrasound imaging of the carotid arteries (CECU) permits direct, real-time visualization of neovascularization in atherosclerotic plaques and is a confirmed predictor of unstable atheromatous lesions. The aim of the study was the assessment of a new, automatically measured index of intensity in quantitative estimation of the contrast flow through the carotid plaque (till now assessed only visually). Forty-four patients (mean age 70.4±11.4) with ultrasound diagnosed significant stenosis of internal carotid artery (ICA), after cerebrovascular or cardiovascular events, qualified for carotid artery stenting (CAS) were examined. The carotid ultrasound examinations with contrast agent Sonovue were performed. Visually in 22 patients (50%) contrast flow through the atherosclerotic plaques was found. In 17 patients (38.6%) massive, calcified atherosclerotic plaques were present. Patients with preserved contrast flow through the plaque more frequently had a history of cerebral stroke (P=0.04). Massive calcifications of atherosclerotic plaques correlated with a previous MI (P=0.03) and the degree of advancement of coronary artery disease (P=0.04), but not with a previous cerebral stroke. Contrast flow through the atherosclerotic plaque positively correlated with values of the index of intensity (r=0.69, P<0.00001). In patients with preserved contrast flow the mean value of the index of intensity was 22.24±3.55 dB as compared with 12.37±7.67 dB - a value present in patients without preserved contrast flow. No significant relation for the degree of calcifications and the value of the index of intensity was found. The assessment of the index of intensity is a novel, simple and automatic method to estimate the degree of contrast flow through the carotid plaque. The values of the index of intensity correlate with the contrast flow through the atherosclerotic plaque, but not with its calcification.

Association of CD147 genetic polymorphisms with carotid atherosclerotic plaques in a Han Chinese population with cerebral infarction.

PubMed

Ni, Tongtian; Chen, Min; Yang, Kang; Shao, Jianwei; Fu, Yi; Zhou, Weijun

2017-08-01

Given the important role of CD147 in the development of atherosclerosis, we speculated that CD147 genetic polymorphisms might influence the formation of carotid atherosclerotic plaques. The study was to investigate the association between CD147 gene polymorphisms and susceptibility to carotid atherosclerotic plaques in individuals with cerebral infarction (CI). Eight SNPs in the regulatory and coding regions of the CD147 gene were examined using polymerase chain reaction-ligase detection reaction (PCR-LDR) in DNA samples from 732 Chinese patients with CI, divided into a carotid plaque group (n=475) and a non-carotid plaque group (n=257). Significant differences were found in the genotypes and allele frequencies of the rs4919862 SNP between the carotid plaque and non-carotid plaque groups of CI patients (P<0.05), while the frequencies of the C allele and the CC genotype in the non-carotid plaque group were significantly lower than those in the carotid plaque group, and the frequencies of the T allele in the non-carotid plaque group were significantly higher than those in the carotid plaque group (P<0.05). In addition, there was strong linkage disequilibrium among the rs4919862, rs8637 and rs8259 sites. In a haplotype analysis, the occurrence rate of the haplotype GATGCAGC was 2.095 times higher in the carotid plaque group than in the non-carotid plaque group (P<0.05). These results showed that the rs4919862 SNP of CD147 was closely associated with carotid atherosclerotic plaques formation. Thus, polymorphisms of the CD147 gene may be related to the tendency for carotid atherosclerotic plaques. Copyright © 2017 Elsevier Ltd. All rights reserved.

Functional magnetic resonance imaging to determine hemispheric language dominance prior to carotid endarterectomy.

PubMed

Smits, M; Wieberdink, R G; Bakker, S L M; Dippel, D W J

2011-04-01

We describe a left-handed patient with transient aphasia and bilateral carotid stenosis. Computed tomography (CT) arteriography showed a 90% stenosis of the right and 30% stenosis of the left internal carotid artery. Head CT and magnetic resonance imaging (MRI) of the brain showed no recent ischemic changes. As only the symptomatic side would require surgical intervention, and because hemispheric dominance for language in left-handed patients may be either left or right sided, a preoperative assessment of hemispheric dominance was required. We used functional MRI to determine hemispheric dominance for language and hence to establish the indication for carotid endarterectomy surgery. Functional MRI demonstrated right hemispheric dominance for language and right-sided carotid endarterectomy was performed. We propose that the clinical use of functional MRI as a noninvasive imaging technique for the assessment of hemispheric language dominance may be extended to the assessment of hemispheric language dominance prior to carotid endarterectomy. Copyright © 2010 by the American Society of Neuroimaging.

Early outcomes of carotid artery stenting.

PubMed

Akar Bayram, N; Bozkurt, E; Ayhan, H; Gürkaş, E; Orhan, G; Ak, F; Bilen, E; Sari, C; Akçay, M; Durmaz, T; Keles, T

2012-03-01

Ischemic cerebrovascular events are the most common reason for patients to be bedridden and the third most common reason for death. Many studies in recent years have demonstrated that carotid artery stenting (CAS) may be an alternative to carotid endarterectomy (CEA). In this study, we aimed to report early outcomes of patients who were treated with CAS in our clinic and discuss practicability, advantages and safety of CAS. Eighty patients who underwent CAS between December 2009 and May 2011 were eligible. The mean age was 65 years (range, 49 - 89 years). Of the study group, 73.75% were males and 26.25% were female. The percentage of asymptomatic patients was 11.7%, and the remaining patients were symptomatic. A distal embolic protection device (Angioguard®) was used in 22% of the patients whereas, in the other patients (78%), a proximal blockage system (Mo.MA®) was used. Self-expandable hybrid stents were implanted in all patients and post-dilatation was performed after implantation. None of the patients suffered from stroke, myocardial infarction or death due to CAS during their hospital stay. The mean follow-up period was 10 months (range 2 - 18 months) after discharge. None of the patients had died or had a stroke, a transient ischemic attack (TIA), or a myocardial infarction during the follow-up period. Re-stenosis was not observed in the follow-up carotid Doppler ultrasonography; flow rates were within normal limits. No major complication was observed during the early follow-up period in patients who underwent CAS in our clinic. Only 2 (2.5%) patients showed transient numbness and weakness and these did not lead to morbidity. In the management guide of extracranial carotid and vertebral artery diseases, CAS, in the light of recent studies, is recommended as an alternative to CEA in recommendations for revascularization. One of the important issues emphasized in this guide is the experience of centers. Very low complication rates after CAS suggested that

Noninvasive characterization of carotid plaque strain.

PubMed

Khan, Amir A; Sikdar, Siddhartha; Hatsukami, Thomas; Cebral, Juan; Jones, Michael; Huston, John; Howard, George; Lal, Brajesh K

2017-06-01

Current risk stratification of internal carotid artery plaques based on diameter-reducing percentage stenosis may be unreliable because ischemic stroke results from plaque disruption with atheroembolization. Biomechanical forces acting on the plaque may render it vulnerable to rupture. The feasibility of ultrasound-based quantification of plaque displacement and strain induced by hemodynamic forces and their relationship to high-risk plaques have not been determined. We studied the feasibility and reliability of carotid plaque strain measurement from clinical B-mode ultrasound images and the relationship of strain to high-risk plaque morphology. We analyzed carotid ultrasound B-mode cine loops obtained in patients with asymptomatic ≥50% stenosis during routine clinical scanning. Optical flow methods were used to quantify plaque motion and shear strain during the cardiac cycle. The magnitude (maximum absolute shear strain rate [MASSR]) and variability (entropy of shear strain rate [ESSR] and variance of shear strain rate [VSSR]) of strain were combined into a composite shear strain index (SSI), which was assessed for interscan repeatability and correlated with plaque echolucency. Nineteen patients (mean age, 70 years) constituting 36 plaques underwent imaging; 37% of patients (n = 7) showed high strain (SSI ≥0.5; MASSR, 2.2; ESSR, 39.7; VSSR, 0.03) in their plaques; the remaining clustered into a low-strain group (SSI <0.5; MASSR, 0.58; ESSR, 21.2; VSSR, 0.002). The area of echolucent morphology was greater in high-strain plaques vs low-strain plaques (28% vs 17%; P = .018). Strain measurements showed low variability on Bland-Altman plots with cluster assignment agreement of 76% on repeated scanning. Two patients developed a stroke during 2 years of follow-up; both demonstrated high SSI (≥0.5) at baseline. Carotid plaque strain is reliably computed from routine B-mode imaging using clinical ultrasound machines. High plaque strain correlates with known

[Clinical and pathological significance of carotid siphon calcification observed on bone condition of brain CT].

PubMed

Matsumoto, Hideyuki; Hamaguchi, Hirotoshi; Nakayama, Takahiro; Oda, Tetsuya; Ikagawa, Takashi; Imafuku, Ichiro

2008-02-01

On plain brain computed tomography (CT), it is difficult to evaluate stenosis of internal carotid artery (ICA) because ICA is surrounded by structures, even though we can observe calcification of carotid siphon in some patients by using bone condition. However the pathologic significance has not been well known. We studied the pathologic significance of carotid siphon calcification observed on bone condition of brain CT. A total of 112 patients who were diagnosed or suspected as cerebrovascular diseases were registered. We classified the calcification into four levels (none, mild, moderate, severe) based on the degree of calcification. Then we compared it with the degree of stenosis of carotid siphon seen on brain magnetic resonance angiography (MRA) and with max intima-medial thickness (IMT) from common carotid artery (CCA) to ICA on carotid ultrasonography. The mean +/- standard deviation of max IMT to none, mild, moderate and severe in the degree of calcification were 1.03 +/- 0.64 (0.4-2.8), 1.65 +/- 0.83 (0.5-4.1), 2.03 +/- 0.83 (0.8-4.1) and 2.81 +/- 1.15 (0.7-6.5) mm, respectively. The calcification on brain CT significantly correlated with the degree of stenosis on brain MRA and with max IMT on carotid ultrasonography. The calcification of carotid siphon on bone condition of brain CT correlated with stenosis of the same portion and atherosclerosis of CCA bifurcation. Recently, on DICOM viewer, clinicians can convert plain condition into bone condition on brain CT due to popularization of PACS. We should pay attention to calcification of carotid siphon in patients with ischemic cerebrovascular diseases because we can estimate the atherosclerosis of both carotid siphon and CCA bifurcation easily and immediately.

Involvement of substance P in neutral endopeptidase modulation of carotid body sensory responses to hypoxia.

PubMed

Kumar, G K; Kou, Y R; Overholt, J L; Prabhakar, N R

2000-01-01

Previously, we showed that carotid bodies express neutral endopeptidase (NEP)-like enzyme activity and that phosphoramidon, a potent inhibitor of NEP, potentiates the chemosensory response of the carotid body to hypoxia in vivo. NEP has been shown to hydrolyze methionine enkephalin (Met-Enk) and substance P (SP) in neuronal tissues. The purpose of the present study is to determine whether NEP hydrolyzes Met-Enk and SP in the carotid body and if so whether these peptides contribute to phosphoramidon-induced potentiation of the sensory response to hypoxia. Experiments were performed on carotid bodies excised from anesthetized adult cats (n = 72 carotid bodies). The hydrolysis of Met-Enk and SP was analyzed by HPLC. The results showed that both SP and Met-Enk were hydrolyzed by the carotid body, but the rate of Met-Enk hydrolysis was approximately fourfold higher than that of SP. Phosphoramidon (400 microM) markedly inhibited SP hydrolysis ( approximately 90%) but had only a marginal effect on Met-Enk hydrolysis ( approximately 15% inhibition). Hypoxia (PO(2), 68 +/- 6 Torr) as well as exogenous administration of SP (10 and 20 nmol) increased the sensory discharge of the carotid body in vitro. Sensory responses to hypoxia and SP (10 nmol) were potentiated by approximately 80 and approximately 275%, respectively (P < 0.01), in the presence of phosphoramidon. SP-receptor antagonists Spantide (peptidyl) and CP-96345 (nonpeptidyl) either abolished or markedly attenuated the phosphoramidon-induced potentiation of the sensory response of the carotid body to hypoxia as well as to SP. These results demonstrate that SP is a preferred substrate for NEP in the carotid body and that SP is involved in the potentiation of the hypoxic response of the carotid body by phosphoramidon.

CT findings of descending necrotising mediastinitis via the carotid space ('Lincoln Highway').

PubMed

Kono, T; Kohno, A; Kuwashima, S; Iimura, F; Fujioka, M; Miyata, R; Mizusawa, Y; Kagawa, F; Kaneko, S; Yoshino, Y; Misawa, M; Ito, M; Otsuka, M; Seki, I

2001-02-01

A 3-year-old girl with fever and neck swelling showed widening of the superior mediastinum on chest radiographs. Contrast-enhanced CT of the neck revealed ill-defined low-attenuation areas with a thick, enhanced rim adjacent to the hypertrophied palatine tonsil. The abscess extended inferiorly within the carotid sheath between the carotid artery and the internal jugular vein into the anterior mediastinum. The carotid space is considered an important conduit of descending necrotising mediastinitis and is called the 'Lincoln Highway' as previously suggested.

Development of a preoperative simulation technique for carotid endarterectomy in patients with contrast contraindications.

PubMed

Nomura, Shunsuke; Hayashi, Motohiro; Ishikawa, Tatsuya; Yamaguchi, Koji; Kawamata, Takakazu

2018-05-19

Vascular and osteological parameters, such as the heights of the carotid bifurcation and distal end of the plaque, are important preoperative considerations for patients undergoing carotid stenosis procedures such as carotid endarterectomy. However, for patients with contrast contraindications such as allergies or nephropathies, three-dimensional computed tomography angiography (3D-CTA) is unavailable, and preoperative evaluation remains challenging. In the present study, we aimed to develop a preoperative simulation for use in patients with contrast-contraindicated carotid stenosis. Images from non-contrast neck CT and magnetic resonance imaging obtained without the Leksell stereotactic frame were uploaded to GammaPlan. Following delineation of various structures, we performed preoperative simulations to determine the relationships between vascular and osteological structures. We applied this technique in 10 patients with carotid stenosis to verify the accuracy of the simulation. In all patients, the GammaPlan simulation successfully visualized the heights of the carotid bifurcation and distal end of the plaque without the use of contrast medium. Furthermore, information regarding the location of internal arterial structures, such as calcifications and unstable plaques, could be incorporated into GammaPlan images. Thereafter, we verified simulation accuracy by comparing the simulation results with 3D-CTA and operative findings. Simulations created using GammaPlan can be used to obtain accurate vascular and osteological information regarding the heights of the carotid bifurcation and distal end of the plaque, without the use of contrast medium. The reconstruction of delineated structures using this technique may be effective for preoperative evaluation in patients with contrast-contraindicated carotid stenosis. Copyright © 2018 Elsevier Inc. All rights reserved.

The 10-year Trend of Periprocedural Complication Following Carotid Artery Stenting; Single Center Experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Jeong-Ho; Kang, Jihoon; Yeo, Min-Ju

PurposeCarotid endarterectomy and stenting are used to treat carotid stenosis, with the volume of carotid artery procedures increasing over the past decade. We investigated the 10-year trend of periprocedural complications with an increasing procedure volume of carotid stenting at a single tertiary hospital.MethodsWe collected 416 consecutive cases (384 patients) of carotid artery stenting performed for either symptomatic (231 cases, 55.5 %) or asymptomatic (185 cases, 44.5 %) internal carotid artery stenosis at a single center. Periprocedural complication was defined as any stroke, myocardial infarction, or death. Procedure-related outcome included any dissection, hemodynamic event, or periprocedural complication.ResultsThe mean age was 68.8 years (82.8 % males;more » range of 20–89 years); 23.9 % were older than 75 years. Before the procedure, 99.3 and 56.0 % of patients received antiplatelet and lipid-lowering medication, respectively. The overall periprocedural complication rate was 3.6 % (1.6 and 5.2 % in the asymptomatic and symptomatic group, respectively). The composite outcome of any stroke or death was 3.4 %. Periprocedural complication and procedure-related outcome showed a decremental trend with increasing procedure volume, and this trend remained after adjusting for confounders.ConclusionsOur study suggests that carotid stenting at an experienced center might reduce the periprocedural complications. Our periprocedural complication rate of carotid artery stenting may be comparable to, or somewhat lower than, that reported in other clinical trials.« less

Thirty-Day Outcome Following Carotid Artery Stenting: A 10-Year Experience from a Single Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karkos, Christos D., E-mail: ckarkos@hotmail.com; Karamanos, Dimitrios G.; Papazoglou, Konstantinos O.

2010-02-15

We aimed to present our experience with carotid angioplasty and stenting (CAS) and to document how the technique evolved over the last decade (1997-2007). A retrospective study of 333 patients (259 men; median age, 69 years) who underwent 336 CAS procedures. Of these, 118 (35%) patients were symptomatic and 164 (49%) lesions involved the left carotid bifurcation. The first 163 patients received a balloon-expandable stent, whereas the remaining 173 received a self-expandable one. Cerebral protection devices were used in the last 84 (25%) procedures. Access was via the femoral artery in all but six cases, in which direct puncture ofmore » the common carotid was necessary. The left common carotid originated from the innominate artery in 18 cases (5%). Conversion to open endarterectomy was necessary in two patients due to inability to remove the filter. Perioperative neurological events included stroke in 6 patients (1.8%), transient ischemic attack in 15 (4.5%), and hyperperfusion syndrome in 10 (3.0%). Three patients died during the first 30 days. As a result, the mortality and the combined stroke/death rate were 0.9 and 2.4%, respectively, with no differences between symptomatic and asymptomatic patients. Bradycardia was noted in 48 patients (14%), and hypotension in 45 (13%). Univariate analysis identified hypertension (P = 0.03), hyperlipidemia (P = 0.02), and current or ex-smoking (P = 0.02) as significant risk factors for death/stroke. On multivariate analysis using logistic regression, only hyperlipidemia [odds ratio (OR), 53.90; 95% confidence interval (CI), 4.19-693.47; P = 0.002] and current or ex-smoking (OR, 63.84; 95% CI,: 4.80-848.68; P = 0.001) remained statistically significant. In conclusion, CAS can be performed safely and effectively, with acceptable mortality, stroke/death, and cardiovascular complication rates. Although technological advances (stent design, cerebral protection devices), perioperative pharmacological management, and increasing

Calcium Phosphate Product Is Associated with Subclinical Carotid Atherosclerosis in Type 2 Diabetes

PubMed Central

Ramírez-Morros, Anna; Granado-Casas, Minerva; Martinez-Alonso, Montserrat; Real, Jordi; Castelblanco, Esmeralda; Esquerda, Aureli; Cao, Gonzalo; Alonso, Núria

2017-01-01

Aims To assess whether circulating 25-hydroxyvitamin D3 (25OHD) and mineral metabolism-related factors (serum phosphate, calcium, and parathormone) are associated with subclinical carotid atherosclerosis (SCA), defined as the presence of carotid atherosclerotic plaques (main study outcome), in patients with type 2 diabetes mellitus (T2DM) without kidney disease or previous cardiovascular disease. Methods We undertook a post hoc analysis of a cross-sectional study in adults with T2DM in whom we evaluated SCA. A total of 303 subjects with T2DM were included. Clinical variables and carotid ultrasound imaging were obtained. Results We found no association of 25OHD with the presence of SCA. However, calcium phosphate (CaP; mg2/dL2) product was positively associated with the presence of carotid plaques (ORadj = 1.078; 95% CI: 1.017–1.142). An inverse association was observed between higher levels of 25OHD (≥30 ng/mL versus <20 ng/mL concentrations) and common carotid intima-media thickness (cIMT; mm) (βadj ± SE = −0.055 ± 0.024). We conclude that the CaP product is independently associated with the presence of established subclinical carotid atherosclerosis in patients with T2DM. PMID:28840128

Advancing Humanities Studies at Community, Technical, and Junior Colleges.

ERIC Educational Resources Information Center

Eisenberg, Diane U.; And Others

The American Association of Community and Junior Colleges' (AACJC's) two-year Advancing the Humanities Project (AHP) has assisted selected community colleges in promoting the humanities on their campuses. Parts I and II of this report on the AHP present statements by Dale Parnell and Judith Jeffrey Howard about the AACJC's humanities initiatives…

Ex Vivo and in Silico Study of Human Common Carotid Arteries Pressure Response in Physiological and Inverted State

NASA Astrophysics Data System (ADS)

Piechna, A.; Cieślicki, K.; Lombarski, L.; Ciszek, B.

2015-02-01

Arterial walls are a multilayer structures with nonlinear material characteristics. Furthermore, residual stresses exist in unloaded state (zero-pressure condition) and they affect arterial behavior. To investigate these phenomena a number of theoretical and numerical studies were performed, however no experimental validation was proposed and realized yet. We cannot get rid of residual stresses without damaging the arterial segment. In this paper we propose a novel experiment to validate a numerical model of artery with residual stresses. The inspiration for our study originates from experiments made by Dobrin on dogs' arteries (1999). We applied the idea of turning the artery inside out. After such an operation the sequence of layer is reversed and the residual stresses are re-ordered. We performed several pressure-inflation tests on human Common Carotid Arteries (CCA) in normal and inverted configurations. The nonlinear responses of arterial behavior were obtained and compared to the numerical model. Computer simulations were carried out using the commercial software which applied the finite element method (FEM). Then, these results were discussed.

Pathology of Human Coronary and Carotid Artery Atherosclerosis and Vascular Calcification in Diabetes Mellitus.

PubMed

Yahagi, Kazuyuki; Kolodgie, Frank D; Lutter, Christoph; Mori, Hiroyoshi; Romero, Maria E; Finn, Aloke V; Virmani, Renu

2017-02-01

The continuing increase in the prevalence of diabetes mellitus in the general population is predicted to result in a higher incidence of cardiovascular disease. Although the mechanisms of diabetes mellitus-associated progression of atherosclerosis are not fully understood, at clinical and pathological levels, there is an appreciation of increased disease burden and higher levels of arterial calcification in these subjects. Plaques within the coronary arteries of patients with diabetes mellitus generally exhibit larger necrotic cores and significantly greater inflammation consisting mainly of macrophages and T lymphocytes relative to patients without diabetes mellitus. Moreover, there is a higher incidence of healed plaque ruptures and positive remodeling in hearts from subjects with type 1 diabetes mellitus and type 2 diabetes mellitus, suggesting a more active atherogenic process. Lesion calcification in the coronary, carotid, and other arterial beds is also more extensive. Although the role of coronary artery calcification in identifying cardiovascular disease and predicting its outcome is undeniable, our understanding of how key hormonal and physiological alterations associated with diabetes mellitus such as insulin resistance and hyperglycemia influence the process of vascular calcification continues to grow. Important drivers of atherosclerotic calcification in diabetes mellitus include oxidative stress, endothelial dysfunction, alterations in mineral metabolism, increased inflammatory cytokine production, and release of osteoprogenitor cells from the marrow into the circulation. Our review will focus on the pathophysiology of type 1 diabetes mellitus- and type 2 diabetes mellitus-associated vascular disease with particular focus on coronary and carotid atherosclerotic calcification. © 2016 American Heart Association, Inc.

Effects of stress reduction on carotid atherosclerosis in hypertensive African Americans.

PubMed

Castillo-Richmond, A; Schneider, R H; Alexander, C N; Cook, R; Myers, H; Nidich, S; Haney, C; Rainforth, M; Salerno, J

2000-03-01

African Americans suffer disproportionately higher cardiovascular disease mortality rates than do whites. Psychosocial stress influences the development and progression of atherosclerosis. Carotid intima-media thickness (IMT) is a valid surrogate measure for coronary atherosclerosis, is a predictor of coronary outcomes and stroke, and is associated with psychosocial stress factors. Stress reduction with the Transcendental Meditation (TM) program decreases coronary heart disease risk factors and cardiovascular mortality in African Americans. B-mode ultrasound is useful for the noninvasive evaluation of carotid atherosclerosis. This randomized controlled clinical trial evaluated the effects of the TM program on carotid IMT in hypertensive African American men and women, aged >20 years, over a 6- to 9-month period. From the initially enrolled 138 volunteers, 60 subjects completed pretest and posttest carotid IMT data. The assigned interventions were either the TM program or a health education group. By use of B-mode ultrasound, mean maximum IMT from 6 carotid segments was used to determine pretest and posttest IMT values. Regression analysis and ANCOVA were performed. Age and pretest IMT were found to be predictors of posttest IMT values and were used as covariates. The TM group showed a significant decrease of -0.098 mm (95% CI -0. 198 to 0.003 mm) compared with an increase of 0.054 mm (95% CI -0.05 to 0.158 mm) in the control group (P=0.038, 2-tailed). Stress reduction with the TM program is associated with reduced carotid atherosclerosis compared with health education in hypertensive African Americans. Further research with this stress-reduction technique is warranted to confirm these preliminary findings.

Baroreflex activation therapy lowers arterial pressure without apparent stimulation of the carotid bodies.

PubMed

Alnima, Teba; Goedhart, Emilie J B M; Seelen, Randy; van der Grinten, Chris P M; de Leeuw, Peter W; Kroon, Abraham A

2015-06-01

Carotid baroreflex activation therapy produces a sustained fall in blood pressure in patients with resistant hypertension. Because the activation electrodes are implanted at the level of the carotid sinus, it is conceivable that the nearby located carotid body chemoreceptors are stimulated as well. Physiological stimulation of the carotid chemoreceptors not only stimulates respiration but also increases sympathetic activity, which may counteract the effects of baroreflex activation. The aim of this exploratory study is to investigate whether there is concomitant carotid chemoreflex activation during baroreflex activation therapy. Fifteen participants with the Rheos system were included in this single-center study. At arrival at the clinic, the device was switched off for 2 hours while patients were at rest. Subsequently, the device was switched on at 6 electric settings of high and low frequencies and amplitudes. Respiration and blood pressure measurements were performed during all device activation settings. Multilevel statistical models were adjusted for age, sex, body mass index, antihypertensive therapeutic index, sleep apnea, coronary artery disease, systolic blood pressure, and heart rate. There was no change in end-tidal carbon dioxide, partial pressure of carbon dioxide, breath duration, and breathing frequency during any of the electric settings with the device. Nevertheless, mean arterial pressure showed a highly significant decrease during electric activation (P<0.001). Carotid baroreflex activation therapy using the Rheos system did not stimulate respiration at several electric device activation energies, which suggests that there is no appreciable coactivation of carotid body chemoreceptors during device therapy. © 2015 American Heart Association, Inc.

Internal Carotid Artery Dissection in Brazilian Jiu-Jitsu.

PubMed

Demartini, Zeferino; Rodrigues Freire, Maxweyd; Lages, Roberto Oliver; Francisco, Alexandre Novicki; Nanni, Felipe; Maranha Gatto, Luana A; Koppe, Gelson Luis

2017-06-01

Carotid artery dissection is a significant cause of stroke in young patients. It may be asymptomatic and go undiagnosed, or minimal transient manifestations may follow, commanding a higher index of suspicion than ordinarily exists to avoid misdiagnosis. Reported herein is a 27-year-old man who suffered extracranial internal carotid artery dissection while practicing a Brazilian Jiu-Jitsu submission maneuver. The patient's condition suddenly deteriorated one week later due to distal embolization and stroke. Despite endovascular treatment, with stenting of the cervical carotid artery, neurologic deficits remained. Of note, the objective in martial arts, which is to kill or incapacitate, has yet to be fully tempered in transitioning to sport. Brazilian Jiu-jitsu, a relatively new and fast-growing form of martial art, places emphasis on submission maneuvers. Related injuries are not common knowledge and are poorly described in the literature. This account is intended to shed light on the risk of this discipline. Through education and improved supervision, vascular injuries of this nature and the potentially lethal or disabling consequences may thus be prevented in young athletes.

Internal Carotid Artery Dissection in Brazilian Jiu-Jitsu

PubMed Central

Rodrigues Freire, Maxweyd; Lages, Roberto Oliver; Francisco, Alexandre Novicki; Nanni, Felipe; Maranha Gatto, Luana A.; Koppe, Gelson Luis

2017-01-01

Carotid artery dissection is a significant cause of stroke in young patients. It may be asymptomatic and go undiagnosed, or minimal transient manifestations may follow, commanding a higher index of suspicion than ordinarily exists to avoid misdiagnosis. Reported herein is a 27-year-old man who suffered extracranial internal carotid artery dissection while practicing a Brazilian Jiu-Jitsu submission maneuver. The patient's condition suddenly deteriorated one week later due to distal embolization and stroke. Despite endovascular treatment, with stenting of the cervical carotid artery, neurologic deficits remained. Of note, the objective in martial arts, which is to kill or incapacitate, has yet to be fully tempered in transitioning to sport. Brazilian Jiu-jitsu, a relatively new and fast-growing form of martial art, places emphasis on submission maneuvers. Related injuries are not common knowledge and are poorly described in the literature. This account is intended to shed light on the risk of this discipline. Through education and improved supervision, vascular injuries of this nature and the potentially lethal or disabling consequences may thus be prevented in young athletes. PMID:29152471

Intracarotid abciximab injection to abort impending ischemic stroke during carotid angioplasty.

PubMed

Ho, D S; Wang, Y; Chui, M; Wang, Y; Ho, S L; Cheung, R T

2001-01-01

Abciximab, a platelet glycoprotein IIb/IIIa receptor antagonist, prevents ischemic complications during percutaneous transluminal coronary angioplasty and was recently shown to open occluded vessels in patients with acute myocardial infarction when used alone or in combination with other thrombolytic agents. In an animal model of arterial thrombosis, abciximab was found to be safe and effective for the prevention of carotid artery thrombosis. However, the safety and efficacy of abciximab in the treatment of acute ischemic cerebrovascular events is unknown at present. We describe 3 patients who experienced ischemic cerebrovascular events with symptoms involving the middle cerebral artery territory while undergoing percutaneous angioplasty and stenting to their internal carotid arteries. Abciximab was administered to each patient within 10 min of symptom onset as a bolus (0.25 mg/kg) into the ipsilateral common carotid artery followed by continuous intravenous infusion (9 microg/min) for 12 h. All patients' symptoms resolved completely (by 25 min, 40 min and 5 h, respectively) with no further neurological complications. Our preliminary observation suggests that abciximab may improve neurological outcome following middle cerebral artery ischemic events associated with carotid angioplasty and stenting. Large prospective studies are warranted to establish the safety and efficacy of abciximab in acute ischemic stroke, either as a primary treatment modality or an adjunct to carotid angioplasty and stenting. Copyright 2001 S. Karger AG, Basel.

Transcatheter Closure of a Chronic Iatrogenic Arteriovenous Fistula Between the Carotid Artery and the Brachiocephalic Vein with an Amplatzer Duct Occluder in Combination with a Carotid Stent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stasek, Josef, E-mail: stasek@fnhk.c; Lojik, Miroslav; Bis, Josef

2009-05-15

We report an original method of transcatheter closure of an arteriovenous fistula using the combination of an Amplatzer PDA occluder and a carotid stent. The fistula was between the left carotid artery and the brachiocephalic vein. The patient had significant left-to-right shunt and was highly symptomatic. Due to the large orifice and pseudoaneurysmatic enlargement of the fistula, we had to use a large Amplatzer PDA occluder and the protruding part of the PDA device disk had to be covered with a carotid stent. The fistula was completely closed. The patient stopped having symptoms and, 2 years after the procedure, themore » effect persists.« less

Carotid intima-media thickness in young survivors of childhood cancer.

PubMed

Krawczuk-Rybak, Maryna; Tomczuk-Ostapczuk, Monika; Panasiuk, Anna; Goscik, Elzbieta

2017-02-01

Radiotherapy (RT) and some chemotherapy regimens are known risk factors predisposing to the development of premature arterial disease. Vascular ultrasound measurement of carotid intima-media thickness (IMT) is a non-invasive technique, useful to detect early subclinical symptoms of atherosclerosis that can appear in the paediatric population. We analysed the influence of chemotherapy and moderate doses of head or neck irradiation in childhood cancer survivors on the possibility of premature carotid artery disease. Ultrasound measurements of the intima-media thickness (IMT) in the common carotid artery (CCA), bulb and internal carotid artery (ICA) were performed in 74 young cancer survivors and in 48 age- and sex-matched controls. In the whole study group, we observed higher IMT in all positions as compared with the control, except for comparable thickness in the CCA (bilaterally). We failed to find any differences in IMT between irradiated and non-irradiated females. In irradiated males, all IMT measurements on the right side were higher than in non-irradiated patients. There was no effect of body mass index, blood pressure, serum cholesterol, triglycerides, fibrinogen and thyroid hormones on IMT. In the irradiated group, a positive correlation was observed between IMT in the right bulb and the post-radiation time. Anticancer treatment during childhood, especially including irradiation to the mediastinum, head or neck, affects the IMT, particularly in males. This suggests a possible role of irradiation in the premature development of carotid artery disease. © 2016 The Royal Australian and New Zealand College of Radiologists.

Carotid Artery Stenting Trials: Conduct, Results, Critique, and Current Recommendations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macdonald, Sumaira, E-mail: sumaira.macdonald@nuth.nhs.uk

2012-02-15

The carotid stenting trialists have demonstrated persistence and determination in comparing an evolving technique, carotid artery stenting (CAS), against a mature and exacting standard for carotid revascularisation, carotid endarterectomy (CEA). This review focuses on their endeavours. A total of 12 1-on-1 randomised trials comparing CAS and CEA have been reported; 6 of these can be considered major, and 5 of these reflect (in part) current CAS standards of practice and form the basis of this review. At least 18 meta-analyses seeking to compare CAS and CEA exist. These are limited by the quality and heterogeneity of the data informing themmore » (e.g., five trials were stopped prematurely such that they collectively failed to reach recruitment target by >4000 patients). The Carotid Stenting Trialists' Collaboration Publication represents a prespecified meta-analysis of European trials that were sufficiently similar to allow valid conclusions to be drawn; these trials and conclusions will be explored. When the rate of myocardial infarction (MI) is rigorously assessed, CAS and CEA are equivalent for the composite end point of stroke/death and MI, with more minor strokes for CAS and more MIs for CEA. These outcomes have a discrepant impact on quality of life and subsequent mortality. The all-stroke death outcomes for patients <70 years old are equivalent, with more minor strokes occurring in the elderly during CAS than CEA. There are significantly more severe haematomas and cranial nerve injuries after CEA. The influence of experience on outcome cannot be underestimated.« less

Staged curative treatment of a complex direct carotid-cavernous fistula with a large arterial defect and an 'oversized' internal carotid artery.

PubMed

Bender, Matthew T; Lin, Li-Mei; Coon, Alexander L; Colby, Geoffrey P

2017-06-14

This is a case of a high-flow, post-traumatic direct carotid-cavernous fistula with a widened arterial defect and a large-diameter internal carotid artery (ICA). The unique aspect of this case is the oversized ICA, >8mm in diameter, which is both a pathological and a therapeutic challenge, given the lack of available neuroendovascular devices for full vessel reconstruction. We present a planned two-stage embolisation paradigm for definitive treatment. Transarterial coil embolisation is performed as the first stage to disconnect the fistula and normalise flow in the ICA. A 3-month recovery period is then allowed for reduction in carotid diameter. Repair of the large vessel defect and pseudoaneurysm is performed as a second stage in a delayed fashion with a flow-diverting device. Follow-up angiography at 6 months demonstrates obliteration of the fistula and curative ICA reconstruction to a diameter <5mm. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A Framework for Human Performance Criteria for Advanced Reactor Operational Concepts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacques V Hugo; David I Gertman; Jeffrey C Joe

2014-08-01

This report supports the determination of new Operational Concept models needed in support of the operational design of new reactors. The objective of this research is to establish the technical bases for human performance and human performance criteria frameworks, models, and guidance for operational concepts for advanced reactor designs. The report includes a discussion of operating principles for advanced reactors, the human performance issues and requirements for human performance based upon work domain analysis and current regulatory requirements, and a description of general human performance criteria. The major findings and key observations to date are that there is some operatingmore » experience that informs operational concepts for baseline designs for SFR and HGTRs, with the Experimental Breeder Reactor-II (EBR-II) as a best-case predecessor design. This report summarizes the theoretical and operational foundations for the development of a framework and model for human performance criteria that will influence the development of future Operational Concepts. The report also highlights issues associated with advanced reactor design and clarifies and codifies the identified aspects of technology and operating scenarios.« less

Swirling flow in a model of the carotid artery: Numerical and experimental study

NASA Astrophysics Data System (ADS)

Kotmakova, Anna A.; Gataulin, Yakov A.; Yukhnev, Andrey D.

2018-05-01

The present contribution is aimed at numerical and experimental study of inlet swirling flow in a model of the carotid artery. Flow visualization is performed both with the ultrasound color Doppler imaging mode and with CFD data postprocessing of swirling flows in a carotid artery model. Special attention is paid to obtaining data for the secondary motion in the internal carotid artery. Principal errors of the measurement technique developed are estimated using the results of flow calculations.

Surgical dissection of the internal carotid artery under flow control by proximal vessel clamping reduces embolic infarcts during carotid endarterectomy.

PubMed

Yoshida, Kazumichi; Kurosaki, Yoshitaka; Funaki, Takeshi; Kikuchi, Takayuki; Ishii, Akira; Takahashi, Jun C; Takagi, Yasushi; Yamagata, Sen; Miyamoto, Susumu

2014-01-01

To evaluate the efficacy of flow control of the internal carotid artery (ICA) by the clamping of the common carotid artery, external carotid artery, and superior thyroid artery during surgical ICA dissection to reduce ischemic complications after carotid endarterectomy (CEA). Sixty-seven patients (59 men; age, 70.5 ± 6.2 years) who underwent CEA by the same surgeon were retrospectively studied. Both conventional CEA (n = 29) and flow-control CEA (n = 38) were performed with the patient under general anesthesia and with the use of somatosensory-evoked potential and near-infrared spectroscopy monitoring as a guide for selective shunting. The number of new postoperative infarcts was assessed with preoperative and postoperative diffusion-weighted images (DWIs) obtained within 3 days of surgery. In addition to surgical technique, the effects of the following factors on new infarcts also were examined: age, side of ICA stenosis, high-grade stenosis, symptoms, and application of shunting. New postoperative DWI lesions were observed in 7 of 67 patients (10.4%), and none of them was symptomatic. With respect to operative technique, the incidence rate of DWI spots was significantly lower in the flow-control group (2.6%) than in the conventional group (20.7%), odds ratio: 0.069; 95% confidence interval: 0.006-0.779; P = 0.031). On multiple logistic regression analysis, age, side of ICA stenosis, high-grade stenosis, symptoms, and the use of internal shunting did not have significant effects on new postoperative DWI lesions, whereas technique did have an effect. The proximal flow-control technique for CEA helps avoid embolic complications during surgical ICA dissection. Copyright © 2014 Elsevier Inc. All rights reserved.

Gasotransmitter Regulation of Ion Channels: A Key Step in O2 Sensing By the Carotid Body

PubMed Central

Prabhakar, Nanduri R.

2014-01-01

Carotid bodies detect hypoxia in arterial blood, translating this stimulus into physiological responses via the CNS. It is long established that ion channels are critical to this process. More recent evidence indicates that gasotransmitters exert powerful influences on O2 sensing by the carotid body. Here, we review current understanding of hypoxia-dependent production of gasotransmitters, how they regulate ion channels in the carotid body, and how this impacts carotid body function. PMID:24382871

Absence of the right common carotid artery: a rare case without separate origins of the internal and external carotid arteries.

PubMed

Quinones, Gretchen; Srinivasan, Ashok

Absence of the common carotid artery (CCA) is a rare anomaly. In the few cases described in the literature, it has been typically associated with separate origins of the internal carotid artery (ICA) and external carotid artery (ECA) Fife (1921), Boyd (1934), Rossiti and Raininko (2001), Cerase et al. (2009), Drazin et al. (2010), Yim et al. (2009), Monaco et al. (2009), Jerius et al. (1995), Dahn et al. (1999), Cakirer et al. (2002), Choi et al. (2015), Bryan et al. (1978), Horowitz et al. (2003), Roberts and Gerald (1978), Rajeshwari (2013), Purkayastha et al. (2006), Maybody et al. (2003), Wood et al. (2011) . To the best of our knowledge, absence of the CCA without separate origins of the ECA and ICA has only been described five times before, one of them in conjunction with a persistent proatlantal intersegmental artery (PIA) Cao et al. (2011) and four with agenesis of the ICA Kobayashi et al. (2013), Kunishio et al. (1987), Chen et al. (2008), Xie et al. (2010) . We present a case of a previously undescribed variation of this rare vascular anomaly. Copyright © 2017 Elsevier Inc. All rights reserved.

Tumor Necrosis Factor-α Regulates Triggering Receptor Expressed on Myeloid Cells-1-dependent Matrix Metalloproteinases in the Carotid Plaques of Symptomatic Patients with Carotid Stenosis

PubMed Central

Rao, Velidi H.; Rai, Vikrant; Stoupa, Samantha; Subramanian, Saravanan; Agrawal, Devendra K

2016-01-01

Objective To determine the relationship between increased triggering receptor expressed on myeloid cells (TREM)-1 and plaque stability in atherosclerotic carotid stenosis. Methods The mRNA transcripts and protein for TREM-1, MMP-1, MMP-9, collagen type I (COL1A1) and collagen type III (COL3A1) were analyzed by qPCR and immunofluorescence in both tissues and VSMCs isolated from atherosclerotic carotid plaques of symptomatic and asymptomatic patients with carotid stenosis. Results The TREM-1, MMP-1 and MMP-9 mRNA transcripts were significantly increased (TREM-1, p<0.01; MMP-1, p<0.01 and MMP-9, p<0.001) while COL1A1 and COL3A1 mRNA transcripts were decreased (p<0.001) in VSMCs isolated from carotid plaques of symptomatic (S) than asymptomatic (AS) patients. Stimulation of cells with TNF-α further increased the mRNA transcripts of TREM-1, MMPs, COL1A1 and COL3A1. Modulation of TREM-1 by treatment with TREM-1 decoy receptor rTREM-1/Fc, and either TREM-1 antibodies or TREM-1 siRNA attenuated the TNF-α induced expression of MMP-1 and MMP-9 (p<0.01) and COL1A1 and COL3A1 (p<0.01) in S compared to AS VSMCs isolated from carotid plaques. Inhibition of NF-kB (BAY 11-7085), JNK (SP600125) and PI3K (LY294002) signaling pathways decreased the expression of TREM-1 (p<0.01), MMP-1 (p<0.001) and MMP-9 (p<0.01) in TNF-α treated VSMCs isolated from S carotid plaques compared to AS patients. Conclusion Increased expression of TREM-1 in S compared to AS patients involving MMP-1 and MMP-9 suggest a potential role of TREM-1 in plaque destabilization. Selective blockade of TREM-1 may contribute to the development of new therapies and promising targets for stabilizing vulnerable atherosclerotic plaques. PMID:27017522

Mining data from CFD simulation for aneurysm and carotid bifurcation models.

PubMed

Miloš, Radović; Dejan, Petrović; Nenad, Filipović

2011-01-01

Arterial geometry variability is present both within and across individuals. To analyze the influence of geometric parameters, blood density, dynamic viscosity and blood velocity on wall shear stress (WSS) distribution in the human carotid artery bifurcation and aneurysm, the computer simulations were run to generate the data pertaining to this phenomenon. In our work we evaluate two prediction models for modeling these relationships: neural network model and k-nearest neighbor model. The results revealed that both models have high prediction ability for this prediction task. The achieved results represent progress in assessment of stroke risk for a given patient data in real time.

Interaction of central venous pressure, intramuscular pressure, and carotid baroreflex function