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1
Mangoush, Omar. "Anti-oxidant properties of the internal thoracic artery and radial artery." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436319.
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Mackenzie, Alison Jill. "Conduit artery structure and function in patients with coronary artery disease." Thesis, University of Glasgow, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402008.
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Krijne, Ruud. "Use of the internal mammary artery as a coronary artery bypass graft." Maastricht : Maastricht : Universitaire Pers Maastricht ; University Library, Maastricht University [Host], 1994. http://arno.unimaas.nl/show.cgi?fid=6957.
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Ruengsakulrach, Permyos. "Safety and efficacy of radial artery conduits for coronary artery bypass surgery /." Connect to thesis, 2001. http://eprints.unimelb.edu.au/archive/00000243.
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Eklöf, Hampus. "On Renal Artery Stenosis." Doctoral thesis, Uppsala University, Department of Oncology, Radiology and Clinical Immunology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5945.
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<p>Renal artery stenosis (RAS) is a potentially curable cause of hypertension and azotemia. Besides intra-arterial renal angiography there are several non-invasive techniques utilized to diagnose patients with suspicion of renal artery stenosis. Removing the stenosis by revascularization to restore unobstructed blood flow to the kidney is known to improve and even cure hypertension/azotemia, but is associated with a significant complication rate. </p><p>To visualize renal arteries with x-ray techniques a contrast medium must be used. In a randomized, prospective study the complications of two types of contrast media (CO<sub>2</sub> and ioxaglate) were compared. CO<sub>2</sub> was not associated with acute nephropathy, but induced nausea and had lower attenuation differences compared to Ioxaglate. Acute nephropathy was related to the ioxaglate dose and the risk was evident even at very low doses if the patients were azotemic with creatinine clearance <40 ml/min. </p><p>Evaluating patients for clinically relevant renal artery stenosis can be done utilizing several non-invasive techniques. MRA was retrospectively evaluated and shown to be accurate in detecting hemodynamically significant RAS. In a prospective study of 58 patients, evaluated with four methods for renal artery stenosis, it was shown that MRA and CTA were significantly better than ultrasonography and captopril renography in detecting hemodynamically significant RAS. The standard of reference was trans-stenotic pressure gradient measurement, defining a stenosis as significant at a gradient of ≥15 mmHg. The discrepancies were mainly found in the presence of borderline stenosis.</p><p>The outcome of percutaneous revascularization procedures showed a technical success rate of 95%, clinical benefit in 63% of treated patients, 30-day mortality 1.5% and major complication rate of 13%. The major complication rate for patients with baseline serum creatinine >300µmol/l was 32%. Our results compare favorably with published studies and guidelines.</p>
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Holt, Jim, and Gregg Mitchell. "Coronary Artery Disease KSA." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/6457.
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Kragsterman, Björn. "Carotid Artery Stenosis : Surgical Aspects." Doctoral thesis, Uppsala University, Department of Surgical Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6834.
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<p>Randomised controlled trials (RCT) have demonstrated a net benefit of carotid endarterectomy (CEA) in stroke prevention for patients with severe carotid artery stenosis as compared to best medical treatment. Results in routine clinical practice must not be inferior to those in the RCTs. The carotid arteries are clamped during CEA which may impair the cerebral perfusion. </p><p>The aim of this thesis was to assess population-based outcomes from CEA, investigate risk factors for perioperative complications/late mortality and to evaluate effects of carotid clamping during CEA. In the Swedish vascular registry 6182 CEAs were registered during 1994-2003. Data on all CEAs were retrieved, analysed and validated. In the validation process no death or disabling stroke was unreported. The perioperative stroke or death rate was 4.3% for those with symptomatic and 2.1% for asymptomatic stenosis (the latter decreasing over time). Risk factors for perioperative complications were age, indication, diabetes, cardiac disease and contralateral occlusion. Median survival time was 10.8 years for the symptomatic and 10.2 years for the asymptomatic group. </p><p>Tolerance to carotid clamping during CEA under general anaesthesia was evaluated in 62 patients measuring cerebral oximetry, transit time volume flowmetry and stump pressure. High internal carotid artery flow before clamping and low stump pressure was associated with decreased oxygenation after clamping suggesting shunt indication. </p><p>In 18 patients undergoing CEA, jugular bulb blood samples demonstrated significantly altered levels of marker for inflammatory activation (IL-6) and fibrinolytic activity (D-dimer and PAI-1) during carotid clamping as compared to radial artery levels. This indicates a cerebral ischaemia due to clamping although clinically well tolerated. </p><p>In conclusion, the perioperative outcome after CEA in Sweden compared well with the RCTs results. Tolerance to carotid clamping may be evaluated by combining stump pressure and volume flow measurements. Although clinically tolerated clamping may induce a cerebral ischaemic response.</p>
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Kragsterman, Björn. "Carotid artery stenosis : surgical aspects /." Uppsala : Acta Universitatis Upsaliensis : Univ.bibl. [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6834.
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Savage, Maria Theresa. "Conduit artery changes in uraemia." Thesis, Queen Mary, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391681.
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Kapur, Akhil. "Coronary artery revascularisation in diabetes." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504904.
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Menon, Ranjith Krishna. "Cervical artery dissection : current concepts." Thesis, St George's, University of London, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.706533.
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Cervical Artery Dissection: Current Concepts Cervical artery dissection is an important cause of ischemic stroke in the young, accounting for at least 30% of ischemic stroke in patients younger than 45 years. The knowledge on etiology, pathogenesis, preference of diagnostic imaging modality and treatment option on cervical artery dissection for the most part, is poorly understood. In my thesis I discuss the current available data on etiology, pathogenesis, clinical and radiological characteristics and treatment options in cervical artery dissection. In this thesis I performed a postal survey to understand the practice on patients with cervical artery dissection in the United Kingdom. Also to establish evidence based treatment in cervical artery dissection separate systematic reviews were performed to determine the safety and therapeutic effectiveness of medical treatment and interventional treatment in cervical artery dissection. The medical arm included studies comparing anticoagulants versus antiplatelets with following study end points of stroke and death. The results obtained from the survey were compared with a similar Canadian study and this showed prevalent ambiguity in the choice of best antirthrombotic treatment in cervical artery dissection. Also the results from the systematic review showed no difference in the efficacy or complications between antiplatelet and anticoagulant therapy. There were no prospective evidence based study establishing the role of thrombolytic treatment and stenting in cervical artery dissection. I also performed a retrospective study on patients diagnosed with cervical artery dissection at St Georges between January 1995 and August 2007. The aim of this study was to identify any radiological and/or clinical markers which may help predict future neurological events. The outcomes from this study were compared with data obtained from 3 other large published studies on cervical artery dissection. The occurrence and the association of pseudoaneurysms in cervical artery dissection were also studied. Cervical Artery Dissection in Stroke Study (CADISS) is a multicentre randomized, prospective feasibility study comparing antiplatelet treatment with anticoagulant treatment in patients with acute cervical artery dissection.
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Stancell-Smith, Gwendolyn Yvonne. "Women and Coronary Artery Disease." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3415.
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Heart disease, including coronary artery disease, affects approximately 42 million women in the United States. Many of those affected are not aware they have the condition. Contributing to the problem is the fact that women are more likely than men to be misdiagnosed and undertreated for heart disease. Morbidity and mortality are high in women affected by heart disease, making the problem important to address. The purpose of this project was to understand the coronary artery or heart disease risk and the treatment for the condition provided for 31 participants at a cardiology service in the Northeast U.S. The project question focused on understanding how coronary artery disease manifest in women and the gender differences in treatment for men and women. A descriptive case design was used by gathering data from patient risk profiles and treatments. Participants were males and females aged between 30 and 80. Qualitative data were obtained through cardiology staff interviews and existing literature. The data were subjected to a content analysis to identify emergent themes. Findings indicated that the women experienced different cardiac symptoms to men, and these differences translated to misdiagnosis and resulting treatment ineffectiveness. This project contributes to social change through raising awareness of the gender differences in heart disease presentation so that providers can recognize and treat the condition effectively.
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Gordon, Cheryl. "Screening for Peripheral Artery Disease." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/1780.
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Peripheral artery disease (PAD) affects 8 to 10 million Americans, and the incidence of PAD is expected to increase as the population ages. A high percentage of the PAD is undiagnosed prior to the onset of a serious cardiovascular event; therefore, the inability to screen and diagnose for PAD in the early stages could hinder efforts to decrease adverse consequences of cardiovascular disease. Individuals with PAD have a 3 to 5 times increased risk of cardiovascular disease (CVD) mortality when compared to people without PAD. Guided by the Stetler model, the purpose of this project was to evaluate the relationship between level of PAD, as measured by skin perfusion pressure, and HbA1c using secondary data obtained from charts of patients within the clinic setting. Data included patient gender, age, degree of PAD, and HbA1c. A Pearson's correlation investigated the relationship between the patients' HbA1c and level of PAD. There was a significant relationship between HbA1c and LT PAD (r = .21, p =.009). There was no relation in RT PAD (r =.01, n = 149, p = .90). There was a significant relationship between HbA1c and age (r = .34, p = .00). Ultimately, the goal of this study was to improve PAD recognition, encourage early intervention, and facilitate effective preventive methods. Critical limb ischemia might be delayed or prevented if it is
identified earlier by screening methodologies. Early identification and treatment of PAD can improve the quality of life and care for individuals suffering with PAD.
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Dichtel, Laura Elisabeth. "Percutaneous Renal Artery Revascularization in Patients with Atherosclerotic Renal Artery Stenosis and Chronic Kidney Disease." Yale University, 2009. http://ymtdl.med.yale.edu/theses/available/etd-03062009-004834/.
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The impact of percutaneous renal artery angioplasty and stenting (PTRAS) for treatment of atherosclerotic renal artery stenosis (ARAS) is not fully understood, especially in patients with chronic kidney disease (CKD). We performed a retrospective cohort study of patients with significant ARAS and moderate to severe chronic kidney disease (estimated GFR 15-60 ml/min/1.73m2) who were treated medically or with PTRAS. The primary endpoint of this study was change in renal function over the first year after treatment. Secondary endpoints included hemodynamic outcomes, antihypertensive medication doses, end stage renal disease (ESRD), and death. We reviewed all patients with a diagnosis of significant ARAS and impaired GFR treated between 1997-2007 in the Veterans Affairs Connecticut Healthcare System (VACHS). A total of 118 patients met inclusion criteria (71 medical treatment, 47 PTRAS), with an average follow-up of 34 months. The students t-test was used to compare baseline characteristics, as well as renal and hemodynamic endpoints between the two treatment groups. The cohort had a mean age of 73 ± 9 years and average baseline GFR of 37.2 ± 14.9 ml/min/1.73m2. Demographic, clinical and laboratory characteristics at baseline were similar between the two groups, with the exception of higher diastolic blood pressure in the stent group at baseline (75 versus 70 mmHg, p=0.028). No statistically significant difference was found between the two treatment groups for any renal endpoints. After a steady decline in GFR in both the medical treatment and stent groups during the 12 months preceding diagnosis (-4.2 versus -4.0 ml/min/1.73m2, p=0.911), GFR stabilized in both groups over the year following diagnosis (decline in GFR of -1.6 versus -1.4 ml/min/1.73m2, p=0.938). Multivariate models did not reveal an association between treatment modality and percent change in GFR during follow-up. No difference was found in blood pressure outcomes at 12 months between the medical and stent groups. Antihypertensive therapy, measured in defined daily doses (DDDs), was significantly higher in the medical treatment group at 12 months (4.5 versus 3.5 DDDs, p=0.048), but lost significance thereafter. In addition, the number of deaths was significantly higher in the stented group on univariate analysis, although this did not remain significant on multivariable Cox analysis. No difference was found between treatment groups in the development of ESRD. These data suggest that, among patients with ARAS and CKD, medical therapy and renal artery stenting are comparable in stabilizing renal function.
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Mussa, Mohamedshafi Yakub. "The radial artery as a coronary artery bypass graft : studies to reduce peri-operative vasospasm." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611084.
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Starkhammar, Johansson Carin. "Periodontitis and coronary artery disease : Studies on the association between periodontitis and coronary artery disease." Doctoral thesis, Linköpings universitet, Kardiologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-86213.
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Periodontitis and coronary artery disease (CAD) are highly prevalent in Sweden’s population; both diseases have complicated pathogeneses and clinical manifestations due to immune-system triggered inflammation. Research in recent years reported that inflammation is a significant active participant in many chronic diseases. The literature described a CAD-periodontitis association, but underlying mechanisms are not fully understood. It is important to acquire knowledge about how periodontitis might influence CAD, which is one of the major causes of illness and death in western countries. Because periodontitis can be treated, this knowledge, when complemented with more knowledge about the CAD-periodontitis association, could lead to CAD prevention. The overall aim of studies reported in this thesis were to investigate the CAD-periodontitis association, and specifically, to: (i) compare periodontal conditions in patients with CAD and subjects without a history of CAD; (ii) study whether or not periodontal status influences outcomes in known CAD over an 8-year period; (iii) study whether or not concentrations and biological activity of hepatocyte growth factor (HGF) in serum from patients with severe CAD are different – depending on whether or not the subjects had periodontitis; and (iv) study concentrations and biological activity of hepatocyte growth factor in serum, saliva, and gingival crevicular fluid in healthy subjects with or without periodontitis. Here is a brief summary: In study I, 161 patients with CAD and 162 controls were compared regarding periodontal disease prevalence and severity. CAD patients had significant coronary stenosis and underwent percutaneous coronary intervention (PCI) or coronary artery by-pass grafts (CABG). Healthy controls were recruited from Sweden’s population database. Twenty-five per cent of the CAD patients had severe periodontitis, compared to 8% of the controls. In a multiple logistic regression analysis (controlled for age and smoking), severe periodontitis indicated an odds ratio of 5.74 (2.07–15.90) for CAD. Study II: Periodontal status was re-examined in 126 CAD patients and 121 controls from the initial sample after 8 years. Periodontal status at baseline was analysed and related to CAD endpoints (i.e., myocardial infarction, new PCI or CABG or death due to CAD) recorded from patients’ medical records and from the death index maintained by the National Board of Health and Welfare. The difference in periodontitis prevalence and severity between the two groups remained unchanged during the 8-year follow up. No significant differences were found regarding CAD endpoints during follow-up in relation to baseline periodontal status in the CAD-patient group. In study III, higher HGF serum concentrations (p<0.001) were found in CAD patients, compared to healthy blood donors, which reflects chronic inflammation. In CAD patients without periodontitis, HGF concentrations increased significantly 24 hours after PCI – in parallel with increased HGF biological activity. In CAD patients with periodontitis, only small fluctuations were seen in HGF values, i.e., concentration and biological activity. HGF biological activity was temporarily elevated after PCI but only in patients without periodontitis. Thus chronic inflammation related to periodontitis might reduce HGF biological activity. In study IV, HGF concentration and biological activity in saliva, in gingival crevicular fluid (GCF), and serum were compared between 30 generally healthy subjects with severe untreated periodontitis and 30 healthy subjects without periodontitis. Compared to periodontally healthy controls, periodontal patients showed higher HGF concentrations in saliva p<0.001, gingival crevicular fluid p<0.0001, and in serum p<0.001. HGF biological activity (measured as the binding affinity to its HSPG and c-MET receptors) was significantly reduced in saliva (p<0.0001) and GCF samples (p<0.0001 for HSPG and p<0.01 for c-MET) from periodontitis patients. The only significant difference in serum samples was an increases in c-MET binding three minutes after subgingival debridement in periodontitis patients (p<0.05), which might reflect that patients had active bursts of periodontitis. In conclusion, CAD patients more often showed severe periodontitis but there were no differences in CAD endpoints during the eight-year follow-up in relation to baseline periodontal status. Periodontitis seems to influence HGF concentration and biological activity in CAD patients, but studies on factors that cause lower HGF biological activity are necessary – to find out if periodontal treatment influences HGF biological activity. Healthy periodontitis patients had higher HGF concentrations locally and systemically, but biological activity was reduced. This might indicate that periodontitis can influence wound healing and tissue repair in other body parts.<br><p>The ISBN 987‐91‐7519‐748‐7 is incorrect. Correct ISBN is 978‐91‐7519‐748‐7.</p>
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Boue, Jenna E. "Sex Differences in Thrombosis with Canine Basilar Artery and Murine Middle Cerebral Artery Thromboembolic Stroke Models." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587048703654416.
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Järhult, Susann J. "Hyperemic Brachial Artery Blood Flow Velocity." Doctoral thesis, Uppsala universitet, Medicin, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-132918.
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This thesis aims to evaluate the blood flow velocity in the Brachial artery during reactive hyperemia. Primarily to appraise the information it might contain regarding cardiovascular function and cardiovascular risk. Ultrasonographic doppler measurements of the Brachial artery were made on the 1016 men and women aged 70 included in the prospective investigation of the vasculature in Uppsala seniors (PIVUS) study. Analysis of the blood flow velocity in the forearm was made in comparison to established methods of estimating endothelial function, clinical markers of cardiovascular risk, the Framingham risk score and global atherosclerosis determined by whole body magnetic resonance angiography. Systolic blood flow velocity was positively related to cardiovascular risk whereas the diastolic velocity was inversely correlated. However, the systolic to diastolic blood flow velocity (SDFV) ratio was more closely associated with cardiovascular risk than its components apart. Ultrasonographic markers of Carotid atherosclerosis were related to the SDFV ratio. Concentric left ventricular remodeling and left ventricular mass index were also associated with the SDFV ratio, but not to its numerator or denominator separately. A similar pattern was found when assessing SDFV ratio in relation to global atherosclerosis, as well as to established markers of arterial compliance and vasodilation. In conclusion, during reactive hyperemia of the Brachial artery, the systolic to diastolic blood flow velocity ratio appears to contain information of additional value than its components separately, independently of established cardiovascular risk factors. Possibly, the SDFV ratio could offer a promising means to estimate cardiovascular risk in aging populations.<br>PIVUS
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Boyd, C. S. "Radiological evaluation of renal artery stenosis." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426973.
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Baskerville, P. A. "The permeability of the artery wall." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376876.
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Hull, James H. K. "Large artery haemodynamics in cystic fibrosis." Thesis, Kingston University, 2010. http://eprints.kingston.ac.uk/20343/.
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Cystic Fibrosis (CF) is the most common lethal autosomal recessive condition and affects approximately 1/2500 Caucasian newborns in the United Kingdom and 70,000 individuals worldwide. The gene defect classically leads to a phenotype comprising significant respiratory I and gastrointestinal manifestations, however is recognised to have multisystem consequences. Over the past 70 years there has been considerable progress in the understanding and treatment of CF such that it has moved from a poorly understood condition, almost universally fatal in infancy, to a complex multisystem disorder now affecting as many adults as children. This 'evolution' of the disease presents new challenges for clinicians and has increased focus on its extra-pulmonary components. In the general population cardiovascular disease is the leading cause of morbidity and mortality and it is now recognised that progressive changes in the structure and function of the large arterial system are a key determinant of this association. Furthermore these changes lead to alterations in large artery haemodynamics which have immediate physiological relevance for myocardial work and oxygen demand but also perfusion of the distal organs. Modern techniques permit large artery haemodynamics to be evaluated simply and effectively using the non-invasive technique of applanation tonometry with pulse wave analysis. The overall aim of this thesis was to use this technique to provide an evaluation of large artery haemodynamics in a cohort of adult patients with CF. The experimental work in this thesis includes a study assessing the validity of the haemodynamic techniques used in this thesis (study A) and three studies evaluating large artery haemodynamics in patients with CF; at rest (study I), in response to exercise (study II) and finally following a therapeutic intervention (study III).
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Ahmed, Nabeel. "Platelet reactivity in coronary artery disease." Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.530480.
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Omar, Sami Ali Abdelhafees. "Inorganic nitrite and conduit artery function." Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/inorganic-nitrite-and-conduit-artery-function(9ebf6714-6e7e-4b0d-bb4c-c060011164d7).html.
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Background: Inorganic nitrite, a metabolite of endogenously produced nitric oxide (NO) from NO synthases, provides the largest endocrine source of directly bioavailable NO. The conversion of nitrite to NO occurs mainly through enzymatic reduction, which is particularly favoured under hypoxia. Thus, current evidence shows that nitrite dilates small resistance arterioles where conditions of hypoxia predominate. Although organic nitrates/nitrites also mediate their principal effects via NO, they are not hypoxia dependent; hence, they selectively dilate muscular conduit arteries, lowering central blood pressures. Inorganic nitrite would be expected to lack such effects. Methods and Results: The effects of local and systemic administration of sodium nitrite on the radial artery (RA) a muscular conduit artery, forearm resistance vessels (forearm blood flow) and systemic haemodynamics in healthy male volunteers (n=43) were examined. Intra-brachial sodium nitrite (8.7 μmol/min) increased RA diameter by 28.3% (95% CI 20.3 to 36.2). Nitrite (0.087-87 μmol/min) displayed similar selectivity as glyceryl trinitrate (0.003-1 μg/min) for conduit arteries, compared to resistance arterioles. Nitrite dose-dependently increased local cGMP production from the dose of 2.6 μmol/min, by 1.1 pmol/min/100ml tissue (95% CI 0.5 to 1.8). Vasodilatation of the RA by nitrite was enhanced by administration of acetazolamide (oral or i.a.) and oral raloxifene (P=0.0248, P < 0.0001 and P=0.0006, respectively) but was inhibited under hypoxia (P < 0.0001) and hyperoxia (P=0.0006) compared to normoxia. Systemic intravenous administration of sodium nitrite (8.7 μmol/ min) dilated the RA by 10.7% (95% CI 6.8 to 14.7) and reduced central systolic BP by 11.6 mmHg (95% CI of difference 2.4 to 20.7), augmentation index and pulse wave velocity, without changing peripheral BP. Conclusions: Nitrite is a normoxia-dependent selective conduit artery dilator. The mechanism is via cGMP, and the effect is enhanced by acetazolamide and raloxifene. The selective central blood pressure-lowering effects of nitrite have therapeutic potential to reduce cardiovascular events.
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Al, Maskari Raya. "Large artery stiffness : genes and pathways." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277874.
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Aortic stiffness underlies systolic hypertension, promotes heart failure and is associated with increased cardiovascular morbidity and mortality. It is regarded as a primary driver of left ventricular hypertrophy and aortic aneurysms and is linked to the pathogenesis of cognitive impairment, stroke and renal failure. Like most cardiovascular traits, aortic stiffness is a complex trait and is moderately heritable, yet the precise molecular mechanisms that underpin the stiffening process remain poorly defined. This study aimed to employ multiple approaches to further identify the genetic basis of aortic stiffness in a large repository of human donor aortas that had undergone ex vivo pulse wave velocity (PWV) phenotyping. The first part of this work sought to investigate the molecular basis of Loeys-Dietz type 4 syndrome in a pedigree with multiple cases of aortic aneurysms and dissections. A missense variant p.(Arg320Cys) was identified in a highly evolutionary conserved region of TGFB2. There was striking upregulation of TGFB1, TGFB2 and pSMAD2/3 on imunocytochemical straining and western blotting of the aortic tissue from the index case confirming the functional importance of the variant. This case highlighted the striking paradox of predicted loss-of-function mutations in TGFB2 causing enhanced TGFβ signalling in this emerging familial aortopathy and underscored the significance of TGFβ signalling in aortic extracellular matrix biology. The second part of this work attempted to characterise the biological basis for the susceptibility locus identified in the most recent genome wide analysis of carotid-femoral PWV. While the locus lies within the 14q32.2 gene desert, it contains regulatory elements, with the transcriptional regulator B-cell CLL/lymphoma 11B (BCL11B) and non-coding RNA DB129663 representing potential targets for these enhancers. The association of five lead SNPs from the genome-wide association studies (GWAS) meta-analysis was examined for ex vivo aortic stiffness and BCL11B and DB129663 aortic mRNA expression. Three of the five SNPs associated significantly with PWV and showed allele-specific differences in BCL11B mRNA. The risk alleles associated with lower BCL11B suggesting a protective role for BCL11B. Despite the strong association, BCL11B protein was not detected in the human aorta; however, qPCR for CD markers showed that BCL11B transcript correlated strongly with markers for activated lymphocytes. In contrast, DB129663 transcripts were detected in 55% of the samples, and of the five SNPs only one showed allele-specific differences in aortic DB129663 transcripts. No significant differences were observed in PWV between samples expressing or lack- ing DB129663, and therefore the implication of this lncRNA in aortic stiffness remains elusive. The BCL11B transcript detected in the human aorta may reflect lymphocyte infiltration, suggesting that immune mechanisms contribute to the observed association with PWV. For the final part of this work genetic associations with aortic stiffness were explored in a candidate gene-based study utilising tagging SNPs to effectively capture the genetic information from linkage disequilibrium blocks. Association analyses were performed in young, healthy ENIGMA study par- ticipants selected for high and low PWV values then validated in the remaining ENIGMA cohorts. The association of four lead SNPs was then examined for ex vivo aortic stiffness in human donor aortas. The tissue expression of these SNPs and their encoded proteins was also explored. Neither the aggrecan nor the fibulin-1 SNPs showed significant associations with ex vivo PWV in the donor aortas. The exonic aggrecan tagSNP rs2882676 displayed differential transcript abundance between homozygous allele carriers but this did not translate at the protein level. Both aggrecan and fibulin-1 were found in the aortic wall, but with marked differences in the distribution and glycosylation of aggrecan, reflecting loss of chondroitin-sulphate binding domains. These differences were age-dependent but the striking finding was the acceleration of this process in stiff versus elastic young aortas. These findings suggest that aggrecan and fibulin-1 have critical roles in determining the biomechanics of the aorta and their modification with age could underpin age-related aortic stiffening.
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Zhang, Dong Ping. "Coronary artery segmentation and motion modelling." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/6367.
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Conventional coronary artery bypass surgery requires invasive sternotomy and the use of a cardiopulmonary bypass, which leads to long recovery period and has high infectious potential. Totally endoscopic coronary artery bypass (TECAB) surgery based on image guided robotic surgical approaches have been developed to allow the clinicians to conduct the bypass surgery off-pump with only three pin holes incisions in the chest cavity, through which two robotic arms and one stereo endoscopic camera are inserted. However, the restricted field of view of the stereo endoscopic images leads to possible vessel misidentification and coronary artery mis-localization. This results in 20-30% conversion rates from TECAB surgery to the conventional approach. We have constructed patient-specific 3D + time coronary artery and left ventricle motion models from preoperative 4D Computed Tomography Angiography (CTA) scans. Through temporally and spatially aligning this model with the intraoperative endoscopic views of the patient's beating heart, this work assists the surgeon to identify and locate the correct coronaries during the TECAB precedures. Thus this work has the prospect of reducing the conversion rate from TECAB to conventional coronary bypass procedures. This thesis mainly focus on designing segmentation and motion tracking methods of the coronary arteries in order to build pre-operative patient-specific motion models. Various vessel centreline extraction and lumen segmentation algorithms are presented, including intensity based approaches, geometric model matching method and morphology-based method. A probabilistic atlas of the coronary arteries is formed from a group of subjects to facilitate the vascular segmentation and registration procedures. Non-rigid registration framework based on a free-form deformation model and multi-level multi-channel large deformation diffeomorphic metric mapping are proposed to track the coronary motion. The methods are applied to 4D CTA images acquired from various groups of patients and quantitatively evaluated.
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Carlson, Erik James. "Vertebral artery elongation during whiplash trauma." [New Haven, Conn. : s.n.], 2008. http://ymtdl.med.yale.edu/theses/available/etd-11212008-114040/.
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Dick, Gregory M. "Coronary artery reactivity in diabetes mellitus." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9809664.
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CHO, Jin-Gun. "Snoring-induced carotid artery endothelial dysfunction." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/10001.
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Heavy snoring has recently been identified as a risk factor for carotid atherosclerosis but the mechanisms are unclear. Studies of snoring have been fraught with difficulties in trying to define a snore, as well as the lack of consensus in how to actually measure a snore during sleep. Therefore, the main aim of this thesis was to go beyond the inherent problems of trying to define a snore, and examine the effects on the carotid artery of the two principle components that underpin the properties of a snore; namely that of (1) vibration energy and (2) increased negative intrapleural pressure changes. The primary outcomes of interest from these studies were the development of carotid endothelial dysfunction due to peri-carotid tissue vibration consistent with the “response to injury” hypothesis of atherogenesis, and reductions in carotid artery wall shear stress, which has also been linked to early atherosclerosis changes. Cardio-respiratory interactive effects over time may provide a potential pathophysiological linkage between snoring and the development of a pro-atherogenic environment within the carotid artery due to a combination of altered haemodynamic wall shear stress, and the induction of endothelial dysfunction from snoring-induced vibrations.
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Fouquet, Olivier. "Les greffons vasculaires en chirurgie coronaire Does a skeletonized internal thoracic artery give less postoperative complications than a non-skeletonized artery for patients undergoing surgery for coronary artery bypass?" Thesis, Angers, 2019. http://www.theses.fr/2019ANGE0039.
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L’utilisation de greffons artériels (Artère Thoracique Interne (Ati)) et/ou veineux est habituelle au cours de pontages coronaires.1) L’hyperplasie intimale (HI) d’une veine est un mécanisme adaptatif lorsque la veine est soumise à un flux artériel. Certaines solutions de conservation semblent limiter cette HI dans des études in vitro. 2) Deux types de circulation extra-corporelle (CEC) sont utilisables : CEC centrifuge dite non pulsée et CEC à galets dite pulsée. L’absence de pulsatilité est à l’origine d’une réaction inflammatoire systémique et créée une altération du tonus myogénique d’artères intermédiaires chez le rat. L’objectif de ce travail était :1) comparer les solutés de conservation sur des veines implantées en position aortique chez le rat. 2) évaluer l’impact des flux générés par les pompes de CEC sur la fonctionnalité endothéliale des ATIs et la réaction inflammatoire systémique. 1) L’implantation d’un greffon veineux conservé dans du sérum hépariné ou du sang autologue hépariné ou dans une solution anti-oxydante type GALA était à l’origine d’une hyperplasie intimale entrainant une occlusion du greffon dans plus de 50% des cas. Une réaction inflammatoire pariétale importante était retrouvée au niveau de la veine et de l’aorte abdominale distale. 2) La réactivité vasculaire était conservée quel que soit le type de pompes. Une réponse inflammatoire systémique est observée alors que le niveau d’inflammation n’était pas modifié dans les artères. En conclusion, 1) l’utilisation d’une solution anti-oxydante ne permet pas de réduire significativement le risque d’hyperplasie intimale lorsque le greffon veineux est implanté en position artérielle 2) l’exposition d’une ATi à une pompe centrifuge et à galets ne modifie pas la réactivité vasculaire ni la fonctionnalité endothéliale<br>Internal thoracic arteries (ITAs) and venous grafts are commonly used in coronary artery bypass grafting. 1) Intimal hyperplasia (IH) constitutes an adaptative mechanism observed when saphenous vein graft is exposed to arterial blood pressure. Storage solutions aiming on decreasing this IH have been identified in previous in vitro studies. 2) Cardio pulmonary bypass can be performed using either a centrifugal pump, with a non -pulsatile flow or a roller pump, producing a pulsatile flow. Non pulsatile flow was showed to induce a systemic inflammatory response therefor damaging the myogenic tone of resistance arteries in a rat model. The aims of this study were : 1) To compare the impact of storage solutions on saphenous vein grafts implanted in aortic position in a rat model. 2) To evaluate the impact of the flow generated by pumps on endothelial functionality of ITAs and the systemic inflammatory response. 1) IH and graft thrombosis occurred in more than 50% of cases when venous graft was stored in heparinized saline solution, autologous heparinized blood or GALA anti-oxydant solution, and implanted in arterial position. A parietal inflammatory response was observed in venous graft as well as distal abdominal aorta. 2) Vascular reactivity was conserved whatever the pump used. Systemic inflammatory response was observed while the intraparietal inflammatory was not modified in the graft. To conclude, 1) the use of GALA anti-oxydant solution did not decrease the risk of intimal hyperplasia when venous graft is exposed to arterial blood flow 2) exposure of internal thoracic artery to centrifugal and roller pumps did not affect endothelial functionality nor vascular reactivity
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Jones, Zachary Ramey. "THE EFFECT OF ARTERY BIFURCATION ANGLES ON FLUID FLOW AND WALL SHEAR STRESS IN THE MIDDLE CEREBRAL ARTERY." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1311.
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Saccular aneurysms are the abnormal plastic deformation of veins and arteries that can lead to lethal thrombus genesis or internal hemorrhaging. Medication and surgery greatly reduce the mortality rates, but treatment is limited by predicting who will develop aneurysms. A common location for saccular aneurysm genesis is at the main middle cerebral artery (MCA) bifurcation. The main MCA bifurcation is comprised of the M1 MCA segment, parent artery, and two M2 segments, daughter arteries. Studies have found that the lateral angle (LA) ratio of the MCA bifurcation is correlated with aneurysm formation. The LA ratio is defined as the angle between the M1 and the larger M2 divided by the angle between the M1 and the smaller M2. When the LA ratio is equal to 1, perfectly symmetrical, no aneurysms are found at the MCA bifurcation. When the LA ratio is greater than 1.6, aneurysms are commonly found at the MCA bifurcation. In the research described here, varying MCA bifurcation angles were compared to uncover any changes to fluid flow and wall shear stress that could stimulate aneurysm growth. Eight pre-aneurysm MCA bifurcation models were created in SolidWorks® using 120 degrees, 90 degrees, and 60 degrees as the angle between the M1 and the larger M2. LA ratios of 1, 1.6 and 2.2 were then used to characterize the other branch angle (60 degrees with a LA ratio of 1 was excluded). These models were imported into COMSOL Multiphysics® where the laminar fluid flow module was used to simulate non-Newtonian blood flow. Fluid flow profiles showed little to no change between the models. Shear stress changed when the LA ratio was increased, but the changed varied between the 120, 90 and 60 degree models. 120 degree models had a 3.87% decrease in max shear stress with a LA ratio of 2.2 while the 90 degree models had 7.5% decrease in max shear stress with a LA ratio of 2.2. Each daughter artery had distinct areas of high shear stress when the LA ratio equaled 1. Increasing the LA ratio or decreasing the bifurcation angle caused the areas of shear stress to merge together. Increasing LA ratio caused shear stress to decrease and spread around the MCA bifurcation. The reduction in max wall shear stress for high LA ratios supports current aneurysm genesis hypothesizes, but additional testing is required before bifurcation geometries can be used to predicted aneurysm genesis.
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Haller, Steven Thomas. "Acute renal injury with renal artery stenting." Connect to full-text via OhioLINK ETD Center, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=mco1121873957.
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Thesis (M.S.)--Medical College of Ohio, 2005.<br>"In partial fulfillment of the requirements for the degree of Master of Science in Biomedical Sciences." Major advisor: Christopher Cooper. Includes abstract. Document formatted into pages: iii, 150 p. Title from title page of PDF document. Title at ETD Web site : Acute renal injury after renal artery stenting. Bibliography: pages 136-147.
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Pelkonen, O. (Outi). "Cervicocephalic artery dissection:radiological study with clinical outcome." Doctoral thesis, University of Oulu, 2004. http://urn.fi/urn:isbn:9514272706.
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Abstract
The aim of this study was to analyze angiographic findings and the presence and topography of cerebral ischemic and/or hemorrhagic lesions in cerebral CT or MRI, and to assess the long-term clinical outcome of a series of 136 consecutive cervicocephalic artery dissection (CCAD) patients. Pulsatile tinnitus was evaluated as a symptom of CCAD. Medical records and films were reviewed retrospectively.
Irregular stenosis was found in angiography in 50% and occlusion in 33% of the dissected cervicocephalic arteries. Irregular stenosis normalized in 81% and occlusion recanalized in 34%. Other findings, such as pseudoaneurysms, intimal flaps, double lumens, and irregular dilatations were rare and often remained unchanged in follow-up.
Pulsatile tinnitus was a presenting symptom in 12% of the CCAD patients, but the majority of patients had concomitant head or neck pain, ischemic brain symptoms, Horner's syndrome, or cranial neuropathies.
Of the 131 patients who underwent brain imaging, 73 (56%) had signs of infarction in cerebral CT or MRI. Occlusion of the dissected vessel was accompanied by infarction in 76%, irregular stenosis in 40%, and other findings only rarely. Of the anterior circulation infarctions, 95% (39/41) were territorial, subcortical, or territorial infarctions with fragmentation and could thus be considered embolic. Subarachnoid hemorrhage was found in CT in 5 of the 22 patients (23%) with intracranial dissection.
The patient's long-term clinical outcome was assessed using two methods: a classification into categories based on neurological symptoms and defects and the modified Rankin Scale (mRS). Of the 136 CCAD patients, 60% recovered with no or mild disability and 79% scored 0–2 on mRS. In the case of dissection of one or more cervicocephalic arteries without occlusion, the figures were 75% and 89%. In the case of occlusive dissection of one or more arteries, only about 35% of the patients recovered well, having no or mild disability, and 61% scored 0–2 on mRS. No significant differences were seen in recovery after intra- and extracranial dissections.
In conclusion: irregular stenosis, which is the most common angiographic finding in CCAD, is associated with brain infarction less frequently than occlusion, and the long-term clinical outcome is good in most cases. Occlusion of the dissected vessel causes more brain infarctions, and only about 35% of the patients recover well, having no or mild disability. More than 10% of CCAD patients have pulsatile tinnitus as a presenting, and sometimes the only symptom.
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Sims, Elliot Craig. "Optimizing coronary artery brachytherapy using targeted radioimmunotherapy." Thesis, Queen Mary, University of London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412000.
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Vollmer, Sandra Jeanne. "Diagonal earlobe creases and coronary artery disease." FIU Digital Commons, 1996. http://digitalcommons.fiu.edu/etd/3066.
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PURPOSE: The purpose of this study was to examine the relationship between the diagonal earlobe crease and the incidence of coronary artery disease.
PATIENTS AND METHODS: A descriptive, correlational, retrospective and concurrent approach was utilized in examining 61 patients, all with a cardiac catheterization within the last six months. All were examined for the presence of diagonal earlobe crease, presence of coronary artery disease, total blood cholesterol levels, age, sex, and past medical histories. Analyses included the Fischer's exact test, regression analysis, and multiple logistic regression analysis.
RESULTS: The mean age of all the subjects 70.3. Mean cholesterol level of all subjects= 199.68. A significant association between presence of earlobe creases and presence of coronary artery disease with P value <0.025. Gender (male) was the most predictive for the presence of CAD of the four covariates (including age, cholesterol, and ELC status), P<0.006. Earlobe status was the second most powerful predictor of CAD status, P=0.019. Neither age (P=0.40) nor cholesterol (P=0.16) were significant predictors of CAD status.
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McLeod, Andrew L. "Coronary artery remodelling, atherosclerosis and vascular function." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/29269.
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Objectives: The aims of the thesis were to assess coronary artery remodelling and plaque load, and to determine whether this influences vascular and endothelial function <i>in vivo</i> in man. Methods: Coronary artery remodelled segments were categorised using intravascular ultrasound (IVUS). Plaque type was characterised directly from spectral analysis of the radiofrequency ultrasound signal. Central arterial stiffness was assessed using non-invasive measures of arterial stiffness obtained by applanation tonometry of the radial, carotid and femoral artery. Coronary artery plaque volume was determined following computerised three-dimensional reconstruction of IVUS images obtained during a motorised pullback device. Coronary vessel area, arterial stiffness and vasomotor responses were determined using IVUS and Doppler Flow measurement and endothelial fibrinolytic response by coronary sinus sampling during selective intracoronary infusions. Conclusions: Pulse wave analysis may be a useful non-invasive surrogate marker for the extent of coronary atherosclerosis. Atherosclerotic risk factors and coronary plaque load are associated with impaired vasomotor and endogenous fibrinolytic function. Though plaque type was similar in remodelled types, negative remodelling was associated with more pronounced local vascular and endothelial dysfunction. These findings collectively suggest an important local interrelationship between coronary vascular structure and function that has implications for the pathophysiology of ischaemic heart disease.
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Maynard, Charles. "Blacks in the coronary artery surgery study /." Thesis, Connect to this title online; UW restricted, 1986. http://hdl.handle.net/1773/8877.
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Korte, Philippus Jacobus de. "Probability analysis in diagnosing coronary artery disease." Maastricht : Maastricht : Universitaire Pers Maastricht ; University Library, Maastricht University [Host], 1993. http://arno.unimaas.nl/show.cgi?fid=5861.
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Vedin, Jenny. "Coronary artery bypass surgery without extracorporeal circulation /." Stockholm, 2005. http://diss.kib.ki.se/2006/91-7140-507-0/.
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Schulz, Katharine I. "Coping strategies in coronary artery disease patients." Virtual Press, 1993. http://liblink.bsu.edu/uhtbin/catkey/862273.
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Ray, Robert Russell. "Pulmonary artery catheters : effects on patient outcome." Honors in the Major Thesis, University of Central Florida, 1998. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/48.
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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.<br>Bachelors<br>Health and Public Affairs<br>Nursing
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Ng, Lih Chyuan. "Store-operated channels in rat pulmonary artery." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248256.
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Williams, Simon Robert Pask. "The physique associated with coronary artery disease." Thesis, Open University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250507.
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Irvine, Craig D. "The behaviour of asymptomatic carotid artery disease." Thesis, University of Bristol, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267228.
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Jashari, Fisnik. "Carotid artery disease : plaque features and vulnerability." Doctoral thesis, Umeå universitet, Kardiologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-111048.
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Background: Atherosclerosis is an important cause of stroke. Ultrasound offers the convenience of real-time and detailed assessment of carotid plaque features as well as arterial wall thickening and composition. Evaluation of these features is important for determining patients’ risk of suffering vascular events and also contributes to selecting the best treatment strategy. Methods: Using ultrasound data analysis we have determined plaque features in the bifurcation and internal carotid artery (ICA), including: surface plaque irregularities, calcification, echogenicity (grey scale median-GSM) and other textural plaque features (Juxtaluminal black area, entropy, coarseness). In addition, intima media thickens (IMT) and its grey scale median (IM-GSM) was measured in common carotid artery (CCA). Using Cone Beam CT (CBCT) we have quantified calcification volume of the carotid plaques extracted after carotid endarterectomy procedure. For the meta-analysis we have used comprehensive meta-analysis software version 3. Study I: We have included 39 patients and we compared carotid plaque features of the contralateral arteries with those located ipsilateral to symptomatic side and arteries of asymptomatic patients. Study II: The accuracy of US to detect atherosclerosis calcification was assessed against CBCT in 88 patients. Study III: Based on the previous vascular events in coronary, carotid and lower extremity arterial system, 87 patients were divided into three groups: asymptomatic, symptoms in one vascular system and symptoms in more that one vascular system. IMT, IM-GSM and plaque features were compared between groups. Study IV: We have meta-analyzed ten cohort prospective studies evaluating carotid plaque echogenicity for cerebrovascular symptoms prediction. Results: Study I. Plaques of the contralateral to symptomatic arteries had similar features to those in symptomatic and more vulnerable than asymptomatic arteries. Study II. Carotid ultrasound was accurate in detecting calcification volumes of ≥8mm3 with very high sensitivity but it was less accurate in detecting lower calcification volumes (<8mm3). Carotid calcification was not different between symptomatic and asymptomatic patients. Study III. Echogenicity of the intima-media complex (IM-GSM), but not its thickness (IMT), was significantly decreased with increasing number of arterial systems affected by atherosclerosis. IM-GSM was lower in patients with prior myocardial infarction and stroke. Study IV. Carotid plaque echogenicity evaluated by US could predict future cerebrovascular events in patients with asymptomatic, relative risk RR 2.72 (95% CI, 1.86 to 3.96), and recurrent symptoms in symptomatic patients, RR 2.97 (95% CI, 1.85-4.78). Conclusion: Plaques located in the contralateral to symptomatic arteries have similar features as symptomatic side and more vulnerable than asymptomatic arteries. Carotid ultrasound could accurately detect larger but not smaller carotid plaque calcification volumes (<8 mm3). Low IM- GSM could identify patients with multi-system atherosclerosis disease, suggesting a better marker for determining systemic atherosclerosis disease burden compared to conventional IMT. Finally, carotid plaque echogenicity predicts future cerebrovascular events in patients with symptomatic and asymptomatic carotid stenosis.
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Ederle, J. R. "Carotid artery disease : treatment and associated risks." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1349377/.
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Carotid artery stenosis is a major risk factor of stroke. Carotid endarterectomy is the established treatment of choice for severe carotid stenosis. Carotid stenting has gained widespread acceptance as alternative treatment, although trials of safety and efficacy have been inconclusive and contradictory. The history of our understanding of stroke and carotid atherosclerotic disease is sketched. Landmark trials of stroke prevention, including the carotid endarterectomy trials are discussed. The long-term results of one of the first trials of endovascular treatment, the Carotid And Vertebral Transluminal Angioplasty Study (CAVATAS) are presented and the results placed in context of other clinical trials of endovascular treatment for carotid stenosis. This Cochrane Review informed the largest completed trial of stenting and surgery in symptomatic carotid stenosis, the International Carotid Stenting Study (ICSS), whose short-term results up to 120 days after treatment are detailed. Age-related white matter changes are thought to be associated with an increased risk of per-procedural stroke and death. A study investigating the risk of stroke or death associated with age-related white matter changes is presented and discussed. CAVATAS has suggested that the risks and benefits of endovascular treatment for carotid stenosis may be similar to those of carotid endarterectomy. The Cochrane review revealed variable results of published randomised clinical trials. ICSS showed that carotid stenting was associated with a significantly higher short-term risk of stroke, myocardial infarction or death up to 120 days after treatment than carotid endarterectomy. Age-related white matter changes were shown to increase the risk of stroke or death in both treatment arms. Carotid endarterectomy should remain the treatment of choice for symptomatic carotid stenosis but stenting remains an option for certain patients, especially those less suitable for carotid endarterectomy. Scope for further research remains to improve patient selection and to compare invasive treatment to modern medical therapy.
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Papadopoulou, Kyriaki. "Neuropsychological sequalae of coronary artery bypass grafting." Thesis, University of East London, 2009. http://roar.uel.ac.uk/3735/.
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Objectives: To assess neurocognitive function after Coronary Artery Bypass Grafting (CABG); to compare and contrast pre- and post-operative test results and to characterise the degree of change in neurocognitive profiles. To identify neuropsychological patterns associated with different impairment models such as hypoxia and stroke. Methods: A comprehensive neuropsychological battery of tests was administered to a small number of individuals undergoing CABG at pre and post operative stage. In order to minimise practice effects, alternate tests were employed for memory, verbal and visuo-spatial functions. Mood measures were included. Results: There were six variables that indicated significant changes. These changes were in Processing Motor Speed, Verbal Executive function, Verbal, Visual learning and Memory, Verbal functions and Visuospatial functions. There was an overall improvement on mood after CABG. Conclusions: There were different neuropsychological sequelae - considering hypoxia and stroke impairment models - in the participants undergoing CABG via Cardiopulmonary Bypass (CPB). Neuropsychological deficits and improvements were identified.
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Groom, Christina Sophia. "Functional outcomes after coronary artery bypass surgery." Thesis, University of Liverpool, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494159.
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Cardiopulmonary Bypass (CPB) isolates the heart from the circulatory system. As a result, Coronary Artery Bypass Graft (CABG) surgery has become a common treatment for coronary artery disease (CAD) relieving angina and improving health related quality of life (HRQOL) and mood. However, CABG has been associated with Central Nervous System (CNS) dysfunction and successful surgery can be marred by cognitive impairment and/or poor HRQOL/ mood.
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Loizou, Christos P. "Ultrasound image analysis of the carotid artery." Thesis, Kingston University, 2005. http://eprints.kingston.ac.uk/20294/.
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Stroke is one of the most important causes of death in the world and the leading cause of serious, long-term disability. There is an urgent need for better techniques to diagnose patients at risk of stroke based on the measurements of the intima media thickness (IMT) and the segmentation of the atherosclerotic carotid plaque. The objective of this work was to carry out a comparative evaluation of despeckle filtering on ultrasound images of the carotid artery, and develop a new segmentation system, for detecting the IMT of the common carotid artery and the borders of the athrerosclerotic carotid plaque in longitudinal ultrasound images of the carotid artery. To the, best of our knowledge no similar system has been developed for segmenting the atherosclerotic carotid plaque, although a number of techniques have been proposed for IMT segmentation. A total of 11 despeckle filtering methods were evaluated based on texture analysis, image quality evaluation metrics, and visual evaluation made by two experts, on 440 ultrasound images of the carotid artery bifurcation. Furthermore, the proposed IMT and plaque segmentation techniques were evaluated on 100 and 80 longitudinal ultrasound images of the carotid bifurcation respectively based on receiver operating chatracteristic (ROC) analysis. The despeckle filtering results showed that a despeckle filter based on local statistics (lsmv) improved the class separation between asymptomatic and symptomatic classes, gave only a marginal improvement in the percentage of correct classifications success rate, and improved the visual assessment carried out by the experts. It was also found that the lsmv despeckle filter can be used for despeckling asymptomatic images where the expert is interested mainly in the plaque composition and texture analysis, whereas a geometric despeckle filter (gf4d) can be used for despeckling of symptomatic images where the expert is interested in identifying the degree of stenosis and the plaque borders. The IMT snakes segmentation results showed that no significant difference was found between the manual and the snakes segmentation measurements. Better segmentation results were obtained for the normalized despeckled images. The plaque segmentation, results showed that, the Lai & Chin snakes segmentation method gives results comparable to the manual delineation procedure. The IMT and plaque snakes segmentation method may be therefore used to complement and assist the final expert's evaluation. The proposed despeckling and segmentation methods will be further evaluated on a larger number of ultrasound images and on multiple experts' evaluation. Furthermore, it is expected that both methods will be incorporated into an integrated system enabling the texture analysis of the segmented plaque, providing an automated system for the early diagnosis and the assessment of the risk of stroke.
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Kolachalama, Vijaya B. "Predictive haemodynamics of the human carotid artery." Thesis, University of Southampton, 2006. https://eprints.soton.ac.uk/41804/.
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This thesis employs parametrically defined geometry of the human carotid artery bifurcation to better understand the relationship between a range of parameters and the associated haemodynamics and to devise strategies to provide guidance for clinical interventions and to assist in the design of stents and grafts. Initially, detailed statistical analysis is applied to a three dimensional parametric computer aided design (CAD) model of the human carotid bifurcation. A Bayesian surrogate modelling technique is proposed and discrete locations in the CAD model are taken as random parameters to form inputs for the surrogate model. A metric, maximal wall shear stress (MWSS) is used as an output for constructing the surrogate model and key geometric parameters which influence MWSS are identified by performing three dimensional steady state simulations on the candidate geometries. The ability of the surrogate model to predict arterial geometries which have minimum and maximum MWSS is also discussed. Using these geometries, techniques are proposed for evaluating the degree of severity with respect to the metric MWSS for any patient. Subsequently, a new metric, the integral of negative mean shear stress (INMSS) is used as an output for constructing a new surrogate model and three dimensional pulsatile simulations are performed on the candidate geometries. An optimisation problem is solved to find out the arterial geometries which have minimum and maximum values of INMSS. Due to the computational expense of performing three dimensional pulsatile studies, further parametric analyses are applied to the design of stents and bypass grafts using a one dimensional model capable of simulating fluid-wall interactions. Subsequently, a cost-effective diagnostic technique is proposed for identifying patients with carotid stenosis who could most benefit from angioplasty followed by stenting. For this purpose, pressure variation factor (PVF) and maximum pressure (pm) are used as metrics to rank the performance of each case. Finally, the Bayesian surrogate modelling technique is used to predict optimal bypass graft configurations which have minimal values of PVF.
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Haller, Steven Thomas. "Acute Renal Injury After Renal Artery Stenting." University of Toledo Health Science Campus / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=mco1121873957.
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