Origin Of Common Carotid Artery Research Articles

Intrinsic Pathway−Mediated Apoptosis in Elastase-Induced Aneurysms in Rabbits

The pathophysiology of saccular aneurysms is complex and multifactorial. The aim of the present study was to understand the mechanism of apoptosis in an elastase-induced aneurysm model in rabbits. Elastase-induced saccular aneurysms were created at the origin of the right common carotid artery in 20 rabbits. Aneurysm samples were harvested at 2 and 12 weeks after creation. Expression of apoptosis-associated proteins, including caspases and bcl-2 proteins, were assessed by Western blot analysis (n = 5 at both time points). Terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling (TUNEL) staining, which indicates the presence of apoptosis, was performed in tissue sections (n = 5 at both time points). The unoperated contralateral common carotid artery was used as a control. Expression of active caspase-3, the final executioner of apoptosis, and caspase-9, the mediator of the intrinsic mitochondrial pathway, was observed in aneurysms at 2 weeks, whereas the expression of activated caspase-8, the mediator of the extrinsic death receptor pathway, was absent at both time points. Expression of antiapoptotic proteins, Bcl-2 and phospho-Bad, was down-regulated in aneurysms compared with controls at 2 weeks. None of these proteins were differentially expressed at 12 weeks. These results were confirmed by the presence of TUNEL-positive cells in some aneurysms at the early time point. In this study of elastase-induced aneurysms in a rabbit model, activation of apoptosis is mediated predominantly by the Bcl-2-mediated intrinsic pathway through the activation of caspase-9.

Outcomes of angioplasty and stenting at the common carotid origin

Background Conventional treatment of stenosis at the common carotid artery origin has involved extra-anatomic bypass using an open cervical approach or median sternotomy. The goal of this study is to determine the procedural feasibility and safety of angioplasty and stenting at the common carotid origin as a less invasive alternative. Methods Between March 1996 and November 2005, a total of 248 carotid angioplasty and/or stenting procedures were performed at our institution. Of these, 8 procedures were performed in 7 patients for treatment of a stenosis or dissection located at the common carotid origin. There were 4 males and 3 females with a mean age of 58 (range, 22-77). Five patients presented with neurologic symptoms. The patients' medical records were retrospectively reviewed for imaging reports (cerebral angiography, computed tomography, or ultrasound) and available clinical follow-up. Brief telephone interviews with patients, immediate family, or care personnel were also used. Procedural and midterm complication rates were calculated. Results Of 8 procedures, 7 (87.5%) resulted in no residual stenosis. The procedural stroke rate was 0 (0%) of 8 procedures. The procedural TIA rate was 2 (25%) of 8 procedures. The mean follow-up was 31.7 months (range, 11.3-75.9 months). In 2 cases, follow-up was clinical only. In the remaining cases, there were clinical and imaging follow-up in the form of cerebral angiography (n = 3), CT angiography (n = 2), and ultrasound (n = 1). There was one recurrent TIA at 30 days and again at 3.1 months (1/8, 12.5%). There were no strokes (0/8, 0%) and there were no TIAs in patients who were initially asymptomatic on presentation. There was one death from an unrelated cause. Conclusion In this series, angioplasty and stenting were effective in relieving stenosis at the common carotid origin and have low rates of ischemic complications.

Horseshoe lung associated with left-lung hypoplasia, left pulmonary artery sling and bilateral agenesis of upper lobe bronchi

Horseshoe lung, a rare congenital anomaly, is almost always associated with unilateral (usually right-sided) lung hypoplasia, and, in most cases, in conjunction with the scimitar syndrome. We present an 8-month-old boy with horseshoe lung associated with left-lung hypoplasia, left pulmonary artery sling and bilateral agenesis of the upper lobe bronchi, diagnosed by multidetector CT (MDCT) imaging. The study also revealed an anomalous origin of the left vertebral artery as the last branch of the aortic arch, distal to the left subclavian artery, and an anomalous origin of the left common carotid artery from the brachiocephalic trunk. A hemivertebral anomaly of the seventh cervical vertebra was incidentally detected. MDCT with high-quality multiplanar and three-dimensional reconstructions is a noninvasive and rapid technique for detecting the complex combination of vascular, tracheobronchial and parenchymal anomalies, and any potential bone anomalies, in one imaging study.

Combined surgical and endovascular approach to treat symptomatic in-stent occlusion of the left common carotid artery origin

Symptomatic occlusive lesions at the origins of the supra-aortic vessels pose challenges for treatment. Endovascular angioplasty and stent placement via the transfemoral approach is possible, but obtaining a stable position for the guide catheter via this approach is technically difficult. The authors describe the case of a 56-year-old man presenting with symptomatic occlusion of a previously placed stent at the origin of the left common carotid artery (CCA). An endovascular revascularization of the left CCA was planned. However, the absence of a lumen proximal to the stent prevented stable placement of a guide catheter via the transfemoral route. Consequently, the authors used a combined surgical and endovascular approach to gain access to the lesion. The left CCA was exposed surgically distal to the occlusion and clamped just proximal to its bifurcation to preserve flow from the external to the internal carotid artery (ICA) and to prevent embolism into the ICA. A wire was passed retrograde through the occlusive lesion and then was subsequently advanced proximally into the femoral sheath. This allowed transfemoral advancement of the appropriate endovascular devices to perform an angioplasty and placement of a stent. The patient remained neurologically stable, and postoperative studies showed improvement in cerebral perfusion. This case demonstrates the feasibility of distal-to-proximal stent delivery with a combined endovascular and surgical approach.

Neck Injury Is Critical to Elastase-Induced Aneurysm Model

We modified the elastase-induced aneurysm model by use of a simple surgical technique in rabbits. A temporary arcuated aneurysm clip was placed at the origin of the right common carotid artery (RCCA), ascertaining the inner edge of the clip blade on the juncture of the RCCA and right subclavian artery (RSCA), and the elastase-induced aneurysm procedure was undertaken. We found elastase and location of the temporary arcuated aneurysm clip are critical to the success of this aneurysm model.

Continuous selective bilateral antegrade cerebral perfusion through anomalous innominate artery for repair of root, ascending aortic and arch aneurysm – challenges, vagaries and opportunities of bovine arch variant anatomy and review of literature

We describe the repair of a root, ascending aortic and arch aneurysm in a 69-year-old man with a bioprosthetic Shelhigh conduit and cylinder, employing continuous bilateral antegrade cerebral perfusion through an anomalous innominate artery with a bovine arch variant anatomy. The origin of both the innominate artery and the left common carotid artery from a common stem from the arch in this bovine arch variant puts the whole cerebral circulation at risk, on one hand, yet provides an opportunity of continuous bilateral antegrade cerebral perfusion through the right brachial, right axillary, right subclavian or innominate artery, during arch reconstruction under lower body, deep hypothermic circulatory arrest. Safety and adequacy of selective cerebral perfusion through the right axillary artery in patients with normal arch vessel origin depends on an intact circle of Willis. In this bovine arch variant, both cerebral hemispheres can be perfused through the right brachial, right axillary, right subclavian or the innominate artery, independent of the integrity of the circle of Willis, because of the origin of the left common carotid artery from the innominate artery, except for the area supplied by the left vertebral artery. Although this is the first report of innominate artery perfusion for arch reconstruction for aneurysm in a bovine arch variant, we believe the method described has important implications for cerebral protection in light of the generally reported incidence of bovine arch from 13 to 35 percent.

Takayasu arteritis presenting as epileptic seizures: a case report and brief review of the literature

Neurological manifestations may complicate Takayasu arteritis (TA) but seizures are rare. A 40-year-old man with TA presented with recurrent episodes of epileptic seizures. Episodes consisted of a brief period of unresponsiveness followed by sudden falling, tonic stiffening and limb jerking. A postictal period with drowsiness, urine incontinence and a temporal loss of memory was also present. A carotid and intracranial duplex ultrasound revealed a reverse flow within the left vertebral artery indicating the presence of subclavian stealing syndrome while extracranial MRA suggested some stenosis at the origin of the left common carotid artery. The EEG was consistent with epilepsy. Neurological manifestations are secondary to ischemia caused by decreased blood flow in the involved carotid and vertebral arteries. Antiepileptic treatment proved effective and may be considered as a reasonable first approach. The stenotic lesions can be managed successfully with angioplasty but these procedures are associated with a high failure rate and may not be needed.

Anatomical variations of the carotid arteries in adult Kenyans

To describe the topography and anatomical variations of the carotid arteries among Kenyans. A descriptive cross-sectional study. Department of Human Anatomy, University of Nairobi. Eighty carotid arteries of forty cadavers were dissected. The bifurcation of the commonest carotid artery was high (above the reference points) in 63.8% of vessels and the external carotid was antero-lateral to the internal carotid artery in 30% of the vessels. A linguo-facial trunk was the most common variation of the external carotid artery. The origin of the right common carotid artery was high and low in 10% and 2.6% of vessels respectively. The carotid arteries show important variability and thus emphasise caution for clinicians during surgical procedures in the neck.

Left common carotid artery arising from the brachiocephalic trunk: a case report

An abnormal origin of the left common carotid artery from the initial portion of the brachiocephalic trunk was found in the superior mediastinum in a 81-year-old Caucasian male cadaver during dissection practice. We report on the exact morphology of that variant that is appeared in an incidence of 0,2% in the literature. We discuss the relative literature and pay attention on the significance of such a variation for clinicians in its recognition and protection.

Gene Expression Profiling of Experimental Saccular Aneurysms Using Deoxyribonucleic Acid Microarrays: Fig 1.

The molecular characteristics of the pathophysiology of saccular aneurysms remain poorly understood. The purpose of the current study was to investigate the expression of various groups of genes at different stages of aneurysm age in elastase-induced saccular aneurysms in rabbits through the use of deoxyribonucleic acid (DNA) microarrays. A microarray consisting of genes related to cell adhesion, apoptosis, cell signaling, growth, inflammation, vascular remodeling, and oxidative stress was constructed by using rabbit nucleotide sequences. Elastase-induced saccular aneurysms were created at the origin of the right common carotid artery (CCA) in 12 rabbits. Two weeks (n=6) and 12 weeks (n=6) after aneurysm creation, ribonucleic acid (RNA) was isolated from the aneurysm and the control unoperated left CCA and was used for microarray experiments. Real-time polymerase chain reaction (RT-PCR) was performed for validation of microarray results. Of 209 genes, 157 (75%) at 2 weeks and 88 (42%) at 12 weeks demonstrated statistically significant differential expression between aneurysm tissue and the control left CCA tissue (P < .05). Multiple genes implicated in vessel wall remodeling were found to be elevated at 2 weeks and at 12 weeks. Expression of cell adhesion molecules and antioxidant enzymes was down-regulated at 2 weeks but was not significantly different from that of controls at 12 weeks. Most transcription factors, inflammatory genes, and structural genes showed underexpression at both time points. The expression profiles of selected genes were confirmed by RT-PCR. Multiple genes in diverse pathways have been differentially expressed in the rabbit aneurysm model.

A 32‐year‐old nursing student with hoarseness and dysphagia to solids

A 32‐year‐old nursing student with hoarseness and dysphagia to solids

Endovascular Stent Grafts for Large Thoracic Aneurysms After Coarctation Repair

Aneurysm formation is a complication not infrequently seen after repair of aortic coarctation and some may enlarge over time. Conventional management of large thoracic aneurysms after aortic coarctation repair has been akin to the surgical treatment of nonspecific aneurysms; however, hypothermic circulatory arrest has been more frequently required because of reoperations. We describe the treatment of a series of patients with large aneurysms using novel endovascular techniques. The database of patients undergoing thoracic endograft placement was reviewed to identify those with thoracic aneurysms after aortic coarctation repair. Clinical, operative, and radiographic data were assessed. Follow-up imaging included spiral computed tomography (CT) scans immediately after deployment, at 6 months, and yearly thereafter. Of 9 patients that were identified, 7 presented for elective repair and 2 were emergencies. The aneurysms measured 4.7 to 7.3 cm in diameter on spiral CT scans. Seven patients underwent carotid to subclavian bypass and subclavian ligation. Endografts were placed abutting the origin of the left common carotid artery. Seven patients were treated with Zenith endografts (Cook, Inc, Bloomington, IN), and 2 with TAG devices (W.L. Gore & Associates, Flagstaff, AZ). Left common carotid angioplasty and stenting was performed in 4 patients. No major complications occurred. A mean follow-up of 24 months (range, 6.4 to 48 months) demonstrated no late endoleaks, ruptures, conversions, or migration. Placement of endovascular stent grafts is a less invasive approach for patients with thoracic aneurysm after aortic coarctation repair, provided there is no residual coarctation or arch hypoplasia. The potential to diminish the magnitude of the surgical procedure and consequences of aortic exposure in a reoperative field is promising and mandates further investigation.

Stent-Graft Treatment of Late Stenosis of the Left Common Carotid Artery Following Thoracic Graft Placement

We report the case of a patient with subtotal occlusion of the origin of the left common carotid artery (CCA) following thoracic graft placement. Retrograde endovascular placement of a stent-graft by minimal cervical access was undertaken to repair the occlusive lesion of the left CCA and prevent future complications of endoluminal thoracic reconstruction. The retrograde endovascular repair of CCA lesions, as other authors have already suggested, may be the treatment of choice in "high-surgical-risk" patients. In these cases where the ostium of supra-aortic trunks is compromised following thoracic aorta stent-graft migration, endoluminal placement of a stent-graft in the CCA can guarantee both maintenance of carotid flow and thoracic stent-graft fixation.

Usefulness of Catheter Angiography in the Evaluation of Common Carotid Artery Origin Occlusion

Currently, catheter angiography is seldom used to evaluate occlusive cervical carotid disease after stroke. Despite the use of a variety of noninvasive tests, only cerebral angiography could document both carotid bifurcation patency and anterograde flow of the internal carotid artery intracranially in two patients with common carotid artery origin occlusion. These findings significantly influenced each patient's treatment. Common carotid artery origin occlusion represents one potential indication for catheter angiography.

Endovascular repair of descending thoracic aortic aneurysm: preliminary experience

To report an initial experience with the endovascular repair of descending thoracic aortic aneurysm (DTAA). Endoprostheses were placed into 41 patients with DTAA between January 2001 and July 2007 which were retrospectively analyzed. The preliminary right-left carotid and left carotid-subclavian bypass was performed in 4 cases in which the distances from the proximal aneurysm to the origin of the left common carotid artery were no longer than 15 mm. EVAR was conducted 1 week after the bypass or immediately. All stent grafts were deployed in proper position. There were two deaths (4.9%) during perioperative period, resulting from multiorgan failure and acute cardiac infarction, respectively. Eighteen endoleaks occurred immediately after EVAR (43.9%), four disappeared after balloon dilatation. There were two acute renal insufficiencies (4.9%), one requiring hemodialysis for more than 30 days. Follow-up, which ranged from 1 to 60 months [median, (18.6 +/- 4.2) months] was carried out in 26 patients (63.4%). Type-I endoleak and type-III endoleak were detected in two patients in 4 years and 2 years after EVAR, might because of migration, and were corrected using another stent-graft each. Two patients died of other diseases during follow-up. Complete thrombosis of the thoracic aneurysm sac with no late migration or endoleaks was revealed on CT at 3 months postoperatively in the remaining patients. The decrease in maximal aneurysm diameter was 0-22 mm [median, (8.3 +/- 4.5) mm] and the prosthetic vascular grafts in four patients with preliminary carotid subclavian bypass surgery were patent during the follow-up period. The treatment of descending thoracic aortic aneurysm with an endovascular approach is feasible with less trauma, quick recovery and less complications. It may offer the best means of therapy for high risk patients.

The influence of hemodynamic forces on biomarkers in the walls of elastase-induced aneurysms in rabbits

Biological and biophysical factors have been shown to play an important role in the initiation, progression, and rupture of intracranial aneurysms. The purpose of this study was to evaluate the association between hemodynamic forces and markers of vascular remodeling in elastase-induced saccular aneurysms in rabbits. Elastase-induced aneurysms were created at the origin of the right common carotid artery in rabbits. Hemodynamic parameters were estimated using computational fluid dynamic simulations based on 3-D-reconstructed models of the vasculature. Expression of matrix metalloproteinases (MMPs), their inhibitors (TIMPs) and markers of vascular remodeling were measured in different spatial regions within the aneurysms. Altered expression of biological markers relative to controls was correlated with the locations of subnormal time-averaged wall shear stress (WSS) but not with the magnitude of pressure. In the aneurysms, WSS was low and expression of biological markers was significantly altered in a time-dependent fashion. At 2 weeks, an upregulation of active-MMP-2, downregulation of TIMP-1 and TIMP-2, and intact endothelium were found in aneurysm cavities. However, by 12 weeks, endothelial cells were absent or scattered, and levels of pro- and active-MMP-2 were not different from those in control arteries, but pro-MMP-9 and both TIMPs were upregulated. These results reveal a strong, spatially localized correlation between diminished WSS and differential expression of biological markers of vascular remodeling in elastase-induced saccular aneurysms. The ability of the wall to function and maintain a healthy endothelium in a low shear environment appears to be significantly impaired by chronic exposure to low WSS.

Molecular Indices of Apoptosis Activation in Elastase-Induced Aneurysms After Embolization With Platinum Coils

Even though endovascular coils have been widely used for the treatment of intracranial aneurysms, the cellular and molecular responses of aneurysms to the coils after embolization remain poorly understood. The aim of the present study was to understand the mechanism of apoptosis in aneurysms embolized with platinum coils in the rabbit model of elastase-induced aneurysms. Elastase-induced saccular aneurysms were created at the origin of the right common carotid artery in 30 rabbits. Aneurysms were allowed to mature for 8 weeks, after which 20 aneurysms were embolized with platinum coils by endovascular means. After 2 (n=10) and 4 (n=10) weeks of implantation, aneurysm samples harboring coils were harvested for apoptotic studies. The remaining 10 uncoiled aneurysms were used as controls; additional controls included the left common carotid artery, which had not undergone any surgical procedure. Control samples were harvested at 12 weeks after aneurysm creation. Expression of procaspases-3, -8, and -9 was elevated in coiled aneurysms embolized with platinum coils at both time points when compared with uncoiled aneurysms and the left common carotid artery. Cleaved caspases-3, -8, and -9 were found to be expressed only at 4 weeks after embolization. Cells within the aneurysm cavity were terminal dUTP nick end-labeling-positive at 4 weeks only. These apoptotic cells were identified as smooth muscle actin-positive cells. Expression of tumor necrosis-alpha was high in coiled aneurysms when compared with controls. There was no significant difference in the expression of Fas ligand among groups. Decreased expression of antiapoptotic proteins Bcl-2 and phospho-Bad, as well as increased expression of proapoptotic proteins Bax and Bid, was observed in coiled aneurysms at both time points. Activation of apoptosis in aneurysms after embolization with platinum coils is induced by both tumor necrosis factor-alpha-mediated extrinsic and Bcl-2-mediated intrinsic pathways.

Prenatal Multicystic Encephalomalacia Due to Anomaly of the Aortic Arch

Multicystic encephalomalacia (ME) usually results from severe hypoxic-ischemic brain damage occurring during the late third trimester of gestation and birth. We report on a case of congenital ME due to a congenital anomaly of the aortic origin of brachiocephalic vessels resulting in subclavian steal syndrome. A 5-day-old term neonate presented with microcephaly and overlapping cranial sutures. Both arms were developed normally. Magnetic resonance imaging of the brain showed extensive bilateral supratentorial ME. Color duplex sonography of the aortic arch and the intracranial and extracranial vessels revealed a stenosis at the origin of the left common carotid artery and atresia of the origin of the left subclavian artery resulting in left-sided subclavian steal syndrome and retrograde perfusion of the basilar artery. Total cerebral blood flow volume was reduced to 22 mL/min. Severely reduced cerebral blood flow volume resulted from left carotid artery stenosis and atresia of the origin of the left subclavian artery with consecutive subclavian steal. Infratentorial brain structures and the left arm remained intact, but supratentorial brain structures were severely affected with ME.

The impact of increasing age on anatomic factors affecting carotid angioplasty and stenting

Current evaluations of carotid artery angioplasty and stenting (CAS) have suggested equivalency compared with carotid endarterectomy (CEA). However, the incidence of stroke and death with CAS may be higher in elderly patients. We assessed the anatomic characteristics of patients undergoing CAS and compared them based on age older or younger than 80 years. The impact of age on the incidence of postoperative complications was also determined. From February 2003 to August 2005, 135 CAS procedures were performed in 133 patients. Digital subtraction angiograms for each patient were evaluated by two independent observers blinded to patient identifiers. Anatomic characteristics that impact the performance of CAS were assessed as either favorable or unfavorable. These included aortic arch elongation, arch calcification, arch vessel origin stenosis, common and internal carotid artery tortuosity, and treated lesion stenosis, calcification, and length. Postoperative events were defined as myocardial infarction, stroke, and death. Fisher's exact test and chi(2) tests were used to determine statistical significance (P < .05). Of the 133 patients treated, 87 (65%) were men and 46 (35%) were women; and 37 (28%) were >or=80 years of age. The cohort >or=80 years old had an increased incidence of unfavorable arch elongation (P = .008), arch calcification (P = .003), common carotid or innominate artery origin stenosis (P = .006), common carotid artery tortuosity (P = .0009), internal carotid artery tortuosity (P = .019), and treated lesion stenosis (P = .007). No significant difference was found for treated lesion calcification or length. Perioperative cerebral vascular accidents occurred in four patients (3.0%, 3 with no residual deficit, 1 with residual deficit), myocardial infarction in three (2.2%), and one patient (0.8%) died secondary to a hemorrhagic stroke. The combined stroke, myocardial infarction, and death rate for the entire population was 3.7%. The rate was significantly increased in patients aged >or=80 years old (10.8%) compared with those aged <80 years old (1%, P = .012). Elderly patients, defined as those aged >80 years, have a higher incidence of anatomy that increases the technical difficulty of performing CAS. This increase in unfavorable anatomy may be associated with complications during CAS. Although the small number of perioperative events does not allow for determination of a direct relationship with specific anatomic characteristics, the presence of unfavorable anatomy does warrant serious consideration during evaluation for CAS in elderly patients.

A Percutaneous Technique for Preservation of Arch Branch Patency During Thoracic Endovascular Aortic Repair (TEVAR):Retrograde Catheterization and Stenting

To report a percutaneous endovascular technique to deal with stent-graft encroachment and coverage (partial or total) of the origin of the left common carotid artery (CCA) or the left subclavian artery during thoracic endovascular aortic repair. Percutaneous retrograde puncture of the left CCA was accomplished with guidewire advancement into the ascending aorta and insertion of a 6-F sheath. Balloon angioplasty and deployment of a stent across the origin of the left CCA successfully recanalized the vessel and restored normal antegrade flow and pressure. It was reasoned that the stent would maintain vessel patency by focally displacing the endograft device, preventing partial or total coverage (and obstruction) of the arch branch origin. This technique has been used successfully in 8 patients, 6 involving the left CCA and 2 the left subclavian artery. Two of the patients were lost to follow-up after 6 and 12 months. The other 6 patients have been followed from 10 to 32 months; the stented vessels have remained patent in all. While the "interposition" of a bare metal stent between a thoracic endograft and the aortic wall is theoretically unappealing and potentially detrimental, as the direct interaction between the devices might undermine the integrity of one or both, we have not seen such problems in this limited clinical experience.