The purpose of this study was to design an experimental model of endotension and to investigate whether attachment site failure without endoleak results in higher aneurysm sac pressure (ASP). Infrarenal aortic aneurysms were created in canines with an elliptical knitted polyester patch. Pressure transducers were inserted into the aneurysm. Group ...

PURPOSE: To determine the pattern of strain and pressure transmitted to an aortic aneurysm wall before and after endovascular exclusion and to evaluate the role of sac thrombus on the conduction of pressure and wall strain. METHODS: Three canine thoracic aortas were used to create abdominal aortic aneurysms (AAA). The ...

The purpose of this study was to compare measurements by MetriCath to intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA). The MetriCath system consists of a low-pressure (200 mm Hg) balloon catheter connected to a pressure transducer and infusion pump linked to a computer that records pressure-volume curves. Cross-sectional area ...

A 54-year-old woman was admitted to our hospital because of heart failure, upper-limb hypertension, and lower-limb claudication. A loud systolic bruit was audible along the middle lower back. An arteriogram confirmed long-segment stenosis from the lower thoracic to the upper abdominal aorta with normal aortic arch. The patient was diagnosed ...

OBJECTIVES: To relate intra-aneurysm sac pressure during endoluminal AAA repair to early and late endoleak, as well as to the aneurysm size upon follow-up. DESIGN: Prospective clinical investigation. METHODS AND PATIENTS: In 46 patients who had their AAAs treated by a stent graft (group I), intra-operative pressure measurement was performed ...

PURPOSE: To investigate the extent to which clinical status is affected by covering the left subclavian artery (LSA) with stent-grafts in the thoracic aorta. METHODS: Stent-graft reconstruction of the thoracic aorta was performed in 23 patients (20 men; mean age 50.8 years, range 17-77) for management of rupture (n = ...

The composition and morphology of the atherosclerotic lesion are currently considered more important determinants of acute coronary ischemic syndromes than the degree of stenosis. When a lesion is unstable, it may rupture and cause an acute thrombotic reaction. A rupture prone plaque contains a large lipid pool covered by a ...

Renovascular hypertension is usually caused by atherosclerotic narrowing of the origin of the renal artery and is much more common than is thought among patients with peripheral vascular disease, carotid stenosis or heart failure. Renovascular hypertension must be distinguished from renal artery stenosis. In true renovascular hypertension, the kidney takes ...

Renovascular hypertension occasionally manifests clinically as electrolyte disorders and albuminuria in addition to elevated blood pressure. A 49-year-old man who had renovascular hypertension also had severe hypokalemia, hyponatremia, polyuria and polydipsia that were treated by an angiotensin-converting enzyme inhibitor and resection of an atrophic kidney with a compromised blood supply. ...

BACKGROUND: Noncompliant prostheses are used in aortic replacement. We hypothesized that this leads to increased distension and wall stress in the aortic root because of the loss of ventriculo arterial coupling. METHODS: Pressure relations in the aortic root caused by changes of aortic elasticity simulating prosthetic aortic replacement were tested ...

An aortic disease patient is typically an older male with a history of atherosclerosis and hypertension. He might have Marfanoid characteristics, a history of cocaine or methamphetamine abuse or history of syphilis. Alternatively, suspect dissection in a pregnant female with complaints consistent with possible aortic problems. During your assessment, zero ...

A recent study has demonstrated that the pulsatility of the ascending aorta is a strong predictive factor for restenosis after coronary angioplasty. However, whether the pulsatility of the ascending aorta is still a significant predictor for restenosis in elderly patients with a stiffer aorta is unknown. We investigated the relation ...

AIMS: Histology and retrospective clinical studies have indicated that the amount of neointimal hyperplasia is dependent on the arterial injury induced during stent implantation. This study analysed, prospectively, the impact of high vs low pressure stent implantation techniques using a second generation stent on intimal hyperplasia and follow-up lumen dimensions. ...

An endoleak results from the incomplete endovascular exclusion of an aneurysm. We developed an experimental model to analyze hemodynamic changes within the aneurysm sac in the presence of an endoleak, with and without a simulated open collateral branch. With a latex aneurysm model connected to a pulsatile pump, pressures were ...

OBJECTIVE: To study the etiology, clinical spectrum. image findings, management and outcome of children with renovascular hypertension (RVH). MATERIAL AND METHODS: Twenty children (aged 5 days to 15 years) were studied and treated for RVH during 1977-1998. In 14 cases hypertension was found during a routine examination. Six cases had ...

BACKGROUND AND PURPOSE: Treatment of ruptured aneurysms with Guglielmi detachable coils (GDCs) has been shown to prevent repeat bleeding. To assess whether GDC coiling alters aneurysmal pressure, we measured intraaneurysmal pressure in two canine types of carotid artery aneurysms before and after GDC placement. METHODS: A 0.014-inch guidewire with a ...

BACKGROUND: Abdominal aortic coarctation above the renal arteries leads to severe hypertension (HTN) above the stenotic site. We have recently shown marked up-regulations of endothelial nitric oxide synthase (eNOS) in heart and thoracic aorta and of neuronal NOS (nNOS) in the brain of rats with severe aortic coarctation above the ...

The mechanical function of a stent deployed in a damaged artery is to provide a metallic tubular mesh structure. The purpose of this study was to determine the exact mechanical characteristics of stents. In order to achieve this, we have used finite-element analysis to model two different type of stents: ...

This article discusses the pathophysiologic features, diagnosis, treatment, and management of patients with renovascular hypertension. Timely diagnosis is important as the disease can carry a more serious prognosis than essential hypertension and is less amenable to drug treatment. Renovascular hypertension also carries a greater risk of progression to accelerated or ...

The mechanism of forward blood flow during cardiopulmonary resuscitation (CPR) remains controversial. We hypothesized that, if the heart acts as a pump, the proximal descending thoracic aorta would be distended during compression by forward blood flow, and would be constricted or remained unchanged if blood flow is generated by increased ...

This study investigates a strategy of low-pressure stenting with concomitant anti-platelet treatment designed to prevent short- and long-term events after stenting. Ninety consecutive patients who underwent percutaneous transluminal coronary angioplasty with stenting using low-pressure stent deployment (mean 8.1 atmospheres) with concomitant anti-platelet therapy based on ticlopidine and aspirin were followed. ...

PURPOSE: factors contributing to pressure transmission through thrombosed or sealed endoleaks have not been elucidated. The purpose of this investigation was to create an ex-vivo model that mimics patent and sealed endoleaks and that can quantitatively analyse the effects of length, diameter and thrombus on pressure transmission to the interior ...

Measuring aortic distensibility has been shown to be useful in adults as a noninvasive method in the early detection of atherosclerosis. This study had two purposes: to assess the stiffness of the abdominal aorta by using two-dimensional echocardiography (2DE) in healthy neonates, children, and adults and to assess aortic distensibility ...

BACKGROUND: Unrepaired aortic coarctation is known to have a detrimental effect on survival. The benefit of coarctation repair on systolic hypertension in adults has been questioned. This retrospective study was conducted to evaluate the impact of repair of aortic coarctation on systolic hypertension in adults. METHODS: Repair of aortic coarctation ...

PURPOSE: To evaluate the effect on dilatation of three types of covering materials used for endovascular stent-grafts. METHODS: Stent-grafts with three types of covering material [0.1-mm polytetrafluoroethylene (PTFE), 0.2-mm PTFE, and 0.15-mm woven polyester] were placed in a fluid circuit. For the pulsatile pressure test, the luminal pressure of 190/130 ...

OBJECTIVE: To determine whether paediatric hydroceles result entirely from a small-calibre patent processus vaginalis, allowing free communication between the abdominal cavity and hydrocele sac, or whether there are other mechanisms. PATIENTS AND METHODS: Twenty-five hydroceles were studied prospectively in 24 boys (aged 18-132 months). Consent for the intraoperative measurements was ...

OBJECTIVE: To characterise cardiopulmonary baroreflex responses and examine the effects of a 45 minute cycling bout late after successful repair of coarctation of the aorta. SUBJECTS: 10 young adults (mean (SEM) age 18.1 (2.6 years)) operated on for coarctation of the aorta 12.7 (3.5) years earlier, and 10 healthy controls. ...

The case of a patient who underwent heart transplantation and cholecystectomy in 1993 and admitted for resection of abdominal aortic aneurysm in May 1997, is reported. About 25 minutes after unclamping the abdominal aorta the patient s blood pressure fell suddenly to 70/40 mmHg. In spite of vigorous fluid administration ...

BACKGROUND: abdominal aortic aneurysm (AAA) distensibility may be an independent predictor of growth and rupture, possibly because it reflects changes in aortic wall structure and composition. AIM: to determine whether AAA distensibility is related to circulating markers of elastin and collagen metabolism. METHODS: sixty-two male patients of median age (IQR) ...

The goal of endovascular grafting of abdominal aortic aneurysms (AAAs) is to exclude the aneurysm sac from systemic pressure and thereby decrease the risk of rupture. Unlike conventional open surgery, branch vessels in the sac (eg, lumbar artery and inferior mesenteric artery [IMA]) are not ligated and can potentially transmit ...

In this communication the authors outline the development of aneurysm clips from those originally used by Walter Dandy to those currently in use. The history is rich in contributions from neurosurgical pioneers and innovators. As a result, the modern neurosurgeon has a wide selection of biocompatible aneurysm clips with known ...

The effects of aging and blood pressure on the structural alterations of the thoracic aorta were examined using male, accelerated senescence-prone, short-lived SAMP11 mice or accelerated senescence-resistant, long-lived SAMR1 mice. The aortic wall thickness increased significantly by 34% in SAMR1 and by 62% in SAMP11 with advanced age. We observed ...

BACKGROUND: A long-term complication of synthetic patch repair of coarctation is true aneurysm formation.Aim: An in vitro study was undertaken to determine the effects of patch angioplasty on aortic geometry and strain adjacent to the patch. METHODS: Segments of human descending thoracic aorta were subject to 10 pressure loading cycles ...

We studied the mural distribution of collagen types I and III and tropoelastin in enhanced experimental atherogenesis induced in rabbits by hyperlipidemia superimposed by hypertension. Animals were fed a high-cholesterol diet for 5 weeks and also subjected to midthoracic aortic coarctation for 4 weeks. Serum cholesterol levels were increased and ...

BACKGROUND: The purpose of this study was to investigate the effects of blood pressure, temperature, and anesthetic agents on outcome in patients undergoing craniotomy for cerebral aneurysms. METHODS: All ruptured and unruptured intracranial aneurysms operated on from 1992 to 1998 were reviewed retrospectively. The data included 297 aneurysms (190 ruptured ...

Pulsatile wall motion has been suggested as a means by which to evaluate abdominal aortic aneurysms after exclusion from the circulation to determine whether the treatment has been effective. The objective of this study was to investigate the relations between pulsatile wall motion and both the mean and pulse pressures ...

BACKGROUND: Endocardial function indexes overestimate myocardial fiber shortening, a geometric effect proportional to wall thickness. We hypothesized that elevated endocardial indexes of left ventricular contractile function after repair of isolated coarctation of the aorta could be related to this effect. METHODS: Chamber dimensions and wall thickness were measured from 59 ...

BACKGROUND: Despite successful surgical repair of aortic coarctation, life expectancy is reduced, and up to one-third of patients remain or become hypertensive. So as to characterize the responses for blood pressure, we have studied 55 patients with surgically repaired coarctation. Their mean age was 11.3 +/- 5.97 years. We documented ...

Hypertension is a well-known risk factor for coronary artery disease and carotid and lower extremity occlusive disease. Surgically induced hypertension in hypercholesterolemic animals results in increased aortic wall motion and increased plaque formation. We tested the hypothesis that reduction in aortic wall motion, despite continued hypertension, could reduce plaque formation. ...

BACKGROUND AND PURPOSE: Recent experimental studies and a few case reports reveal that coiling may not lead to permanent occlusion of aneurysms by an organized thrombus. Therefore, biologic long-term prognosis seems to be doubtful, and the physical effect of coils may be important. The purpose of this study was to ...

We report the case of a child who developed severe renovascular hypertension six months after acute Kawasaki disease. The hypertension was well controlled with enalapril, but there was a gradual decrease in function of the affected kidney. The lesion, an ostial stenosis of the right main renal artery, was not ...

The aim of the study was to investigate the effect of two various atherogenic stimuli (vasopressin-induced hypertension or hypercholesterolemia) on the collagen and glycosaminoglycan (GAG) content in the internal or external part of both thoracic and abdominal aorta, which are differently susceptible to atherosclerosis. Experimental rabbits were divided into four ...

BACKGROUND: The GFX stent is a balloon-expandable stent made of sinusoidal element of stainless steel. The adjunct high-pressure balloon dilatations were usually recommended in routine stenting procedure. HYPOTHESIS: The aim of this study was to evaluate the immediate and long-term clinical and angiographic outcomes and to investigate the necessity of ...

We compared the impact of low and high-pressure balloon inflation on acute and late angiographic results of Multilink stent. Low-pressure balloon inflation (9.5 +/- 1.9 atm) was used in 43 stents and high pressure (17.1 +/- 1.5 atm) in 44. A larger immediate luminal gain was achieved in stents with ...

INTRODUCTION: Patients with carotid stenosis are at high risk of vascular events and therefore require an optimal control of risk factors such as hypertension. As the treatment of hypertension differs according to the cause, we examined the prevalence of resistant hypertension, and the cause of hypertension, among patients with carotid ...

PURPOSE: To evaluate mechanical property changes after endovascular stent placement in small-diameter arteries. MATERIALS AND METHODS: Self-expanding stents (Wallstent) were placed in the infrarenal aorta of five New Zealand White rabbits via a surgical right femoral approach. Blood pressure changes (deltaP) were monitored in the aorta. Blood flow velocity was ...

A 68-year-old woman was found to have atypical coarctation of the aorta, accompanied by systolic hypertension of the upper extremities despite administration of five types of antihypertensive drugs. Since the systolic hypertension was resistant to the conventional antihypertensive therapy, axilloiliac artery bypass grafting with a subcutaneous tunnel was performed to ...

Patients with coarctation of the aorta can be treated either with surgery or with balloon angioplasty. So far, the last method has proved to be successful in children, but results of this treatment in (young) adults are virtually unknown. The aim of this study was to evaluate the immediate and ...

Hypertension occurring in teenagers and young adults is uncommon. Though the most common form is still essential hypertension, secondary causes are more commonly found here than in older adults. Renal, cardiovascular and endocrine diseases constitute most of these causes. Coarctation of the aorta is the most common cardiovascular cause of ...

Coarctation of the reconstructed aorta after the modified Norwood procedure for hypoplastic left heart syndrome is a relatively common occurrence that can have significant adverse effects. From 1992-98, 65 infants with hypoplastic left heart syndrome or variants thereof underwent a modified Norwood procedure. Of the 50 survivors of Stage I ...