Search Results
Results 351 - 400 of 578
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Pan X M - - 1995
Several studies have investigated the correlation between Doppler ultrasonography (DUS), angiography (CA), and magnetic resonance angiography (MRA) in the evaluation of stenosis of the carotid bifurcation. However, these studies suffer from the lack of a true control-the lesion itself-and therefore conclusions about the diagnostic accuracy of each method remain relative. ...
Hutchison K J - - 1995
Peak analysis was applied to pulsed Doppler ultrasound spectra from in vivo poststenotic velocity fields of canine common carotid arteries. Turbulent spectra from a region of jet breakup, five diameters (5 D) down from a 68% diameter reducing stenosis, were closely approximated by a single Gaussian peak. Multiple peaks resulting ...
Klyachkin M L - - 1994
This study describes the two-dimensional compliance changes that develop in low-grade hemodynamically insignificant stenoses. Twenty-four male Sprague-Dawley rats were used in the study. In 14 rats, balloon injury and endothelial denudation of the common carotid artery was followed by the application of a ligature, which produced a 20% narrowing of ...
Fleming R M - - 1994
BACKGROUND: Assessment of coronary artery disease by quantitative coronary arteriography (QCA), while highly accurate, is more expensive than visual estimates of disease and involves the measurement of numerous variables requiring specialized equipment and personnel, thereby reducing its clinical applicability. In part 1 of this paper, the independent variables that influence ...
Grillo H C - - 1994
Resection and reconstruction of long congenital tracheal stenosis often is impossible or results in excessive anastomotic tension. Anterior tracheoplasty using a patch of pericardium or cartilage may result in granulation tissue needing repeated bronchoscopies, tracheostomy, and stents and may produce recurrent stenosis. Tracheoplasty may be performed by dividing the stenosis ...
Komaru T - - 1994
GTP-binding regulatory proteins (G proteins) regulate various biological functions, but their participation in controlling coronary microvascular tone has not been established yet. The goal of the present study was to elucidate the role of pertussis toxin (PTX)-sensitive G protein in regulating coronary microvascular tone during autoregulation and ischemia. In 42 ...
Madl C - - 1994
Atherosclerotic stenosis of the carotid arteries decreases cerebral flow volume and perfusion, and may result in brain dysfunction. We studied the relationship between the degree of carotid artery stenosis and cognitive brain function in non-demented patients. Cognitive brain function was assessed in 76 patients with carotid artery stenosis (38 patients ...
Bude R O - - 1994
Recent studies have investigated the detection of significant arterial stenoses through identification of the "pulsus tardus" phenomenon in Doppler waveforms obtained distal to the stenosis. The etiology of this phenomenon, however, has not yet been determined. Using an in vitro model based upon an electrical circuit analogy, the authors had ...
Ito T - - 1994
Gastrointestinal bleeding is not rare in patients with calcific aortic stenosis (AS) in Western countries, which has suggested an association between the two conditions. However, there has been no previous report of this association in Japan. In this report we describe a patient with AS who had recurrent gastrointestinal bleeding. ...
Epstein N E - - 1994
Thoracic stenosis may be defined by a narrowing of the anteroposterior (AP) diameter of the thoracic spinal canal to < 10 mm. Primary thoracic stenosis, documented when myelography is carried beyond the thoracolumbar junction into the upper thoracic canal, is most frequently associated with lumbar stenosis, whereas secondary stenosis, attributed ...
Wandt B - - 1994
In recent years the continuity equation has been established as a valuable non-invasive method for calculating aortic valve area. The continuity equation cannot be used if there is calcification or sub-valvular stenosis in the left ventricle-outflow tract, because the area of the outflow trace is not circular in those cases. ...
Figi F A - - 1994
1. Treatment for chronic stenosis of the larynx should be delayed until the patient is in the best possible general condition and until any local inflammatory reaction has entirely cleared. 2. The type of treatment indicated in a given instance depends largely on the character and extent of the stenosis ...
Stansby G - - 1994
Intermittent claudication can be due to spinal canal stenosis. In order to define the frequency with which this condition presents to a vascular surgeon a review of 271 patients referred with claudication was carried out. Twenty-one (8%) were ultimately diagnosed as having spinal stenosis. There were no significant differences with ...
Bude R O - - 1994
PURPOSE: To determine, with hydrodynamic experiments, the true cause of pulsus tardus, a Doppler waveform alteration that often occurs distal to an arterial stenosis. MATERIALS AND METHODS: A flow phantom was constructed with a pulsatile pump, interchangeable stenoses of varying degree, and interchangeable poststenotic segments of tubing with various degrees ...
Atar D - - 1994
This study compares the use of hand-held calipers to automated quantitative coronary arteriography in assessing coronary artery stenosis severity. 48 stenoses in the visually estimated range of 30-90% were evaluated in two orthogonal projections. Absolute stenosis dimensions and calculated transstenotic pressure gradient (PG) were compared. Hand-held calipers were of limited ...
Veen G - - 1993
OBJECTIVES: In the APRICOT study (Antithrombotics in the Prevention of Reocclusion In Coronary Thrombolysis), we sought to determine whether angiographic characteristics of the culprit lesion could predict reocclusion after successful thrombolysis and to analyze the influence of three antithrombotic treatment regimens. BACKGROUND: After successful thrombolysis, reocclusion is a major problem. ...
Verlato F - - 1993
Although pathology of the innominate artery (IA) is not frequent, it causes relevant impairment of extracranial circulation and sometimes cerebrovascular events. Definite differentiation of high-grade stenosis from occlusion of the IA has not been obtained until now with continuous-wave (C.W.) Doppler and duplex system ultrasound, and thus the direct evaluation ...
Kleinert S - - 1993
OBJECTIVES: This study was designed to identify, by echocardiography, morphometric abnormalities of the left ventricular outflow tract in children with fixed subaortic stenosis and to determine whether these abnormalities precede the development of subaortic obstruction. BACKGROUND: Fixed subaortic stenosis typically develops and progresses after the 1st year of life and ...
Hashimoto T - - 1993
We assessed the usefulness of dipyridamole radionuclide ventriculography for detecting significant coronary artery stenosis in 89 patients who were undergoing cardiac catheterization. Radionuclide ventriculography was performed before and after the infusion of dipyridamole (0.56 mg/kg). The end-diastolic regions of interest of the left ventricle were divided into 5 sectors for ...
Bashore T M - - 1993
The prevalence, anatomy and physiology, clinical manifestations, laboratory findings, and management of patients with aortic/mitral obstruction and coarctation of the aorta are assessed. Subaortic stenosis reviewed includes discreet membranous and tunnel subaortic stenosis as well as hypertrophic obstructive cardiomyopathy. The discussion of valvular aortic stenosis includes both congenital and acquired ...
Kolansky D M - - 1993
The presence of intracoronary thrombus is associated with increased complications during coronary angioplasty. Such thrombus may also mimic the appearance of a critical stenosis. We report a case of nearly occlusive intracoronary thrombus which resolved after prolonged heparin therapy, revealing only a minimal underlying stenosis. The recognition and treatment of ...
Kontos G J GJ Jr Midwest Cardiovascular Center, Sioux Falls, - - 1993
Postintubation damage is a potential hazard in any patient intubated with an oral or nasal endotracheal tube or with a tracheostomy tube for ventilatory support. Postintubation tracheal stenosis may be fatal unless it is recognized and treated promptly. This paper reviews the important features of diagnosis and treatment of postintubation ...
Har-El G - - 1993
We present our experience with circumferential tracheal resection with end-to-end anastomosis. Between 1985 and 1992 we performed this procedure on 19 patients with tracheal stenosis. The cause of the stenosis was related to intubation and/or tracheotomy in 78.9% of the patients. Two to 8 tracheal rings were resected and a ...
McCaffrey T V - - 1993
Seventy-five cases of laryngotracheal stenosis treated between 1981 and 1991 were reviewed to determine the effectiveness of surgical treatment on the basis of site and severity of stenosis. Decannulation and absence of exertional dyspnea were the criteria of successful management. The treatment methods used were endoscopic laser incision and dilatation, ...
Tsang V - - 1993
Pulmonary artery sling with concomitant funnel-shaped tracheal stenosis is a rare but potentially lethal congenital condition. Conventional surgical division and reanastomosis of the aberrant left pulmonary artery to the main pulmonary artery carries a high risk of postoperative ventilatory difficulty from an uncorrected tracheal stenosis. A primary tracheal approach via ...
Kumar A - - 1993
Isolated supravalvular aortic stenosis (SVAS) commonly is an autosomal dominant trait; it may also occur in the Williams syndrome (WS). While peripheral pulmonary stenosis (PPS) can occur in the same individual with familial isolated SVAS, concurrence of these lesions in different relatives of a family is uncommon. We describe five ...
Branco G - - 1993
We describe a patient with an ecstatic basilar artery in whom MRI showed marked indentation of the floor of the third ventricle and backward displacement of the midbrain, probably causing aqueduct stenosis. It appeared likely that the associated hydrocephalus was due not only to any "water-hammer" effect, but also to ...
Roger V L - - 1993
Aortic stenosis is a progressive disease. The mechanisms and patterns of progression have been studied over the years using clinical assessment, cardiac catheterization, and more recently, Doppler echocardiography. Doppler is the ideal tool with which to study the progression of aortic stenosis since it provides accurate hemodynamic data non-invasively and, ...
McCaffrey T V - - 1992
Seventy-two cases of laryngotracheal stenosis treated from 1981 through 1991 were reviewed to develop a system of classification which would be useful in predicting the outcome of treatment. Decannulation and absence of dyspnea after exertion were the criteria of successful management. The probability of decannulation over time was computed using ...
Han J K - - 1992
Endobronchial tuberculosis is present in 10-40% of patients with active pulmonary tuberculosis, and more than 90% of the patients with endobronchial tuberculosis have some degree of bronchial stenosis. The primary treatment for tuberculous bronchial stenosis is antituberculous chemotherapy combined with steroids, but some patients do not respond well, and more ...
Ziemer G - - 1992
Pulmonary artery sling is often associated with tracheal stenosis. In many cases repair of the vascular anomaly alone does not relieve dyspnea. Primary one-stage repair with long segment tracheal resection (2.4 cm) and relocation of the left pulmonary artery using cardiopulmonary bypass and deep hypothermic circulatory arrest is described in ...
Akishita M - - 1992
This study was undertaken to investigate the accuracy and reliability of videodensitometry (VDM) in measuring the magnitude of coronary arterial stenosis on coronary angiogram (CAG). CAG taken after administration of sublingual nitroglycerin was analyzed with VDM (XR-70 Coronary Analyzer, Vanguard). The magnitude of stenosis in coronary segments with four different ...
Geggel R L - - 1992
A monozygotic twin boy with supravalvar aortic stenosis had reduction in the degree of obstruction with body growth. His twin brother had normal cardiac anatomy. To our knowledge, this is the first report of improvement without intervention in a patient with supravalvar aortic stenosis and of discordance of supravalvar aortic ...
Nakatani S - - 1992
BACKGROUND: Quantitative assessment of coronary artery stenoses plays a central role in clinical decision making. According to the continuity equation, the ratio of the time-velocity integral of prestenotic to stenotic flow velocities represents the ratio of the cross-sectional area of the stenotic to prestenotic segments. However, no data exist regarding ...
Stewart A D - - 1992
Two patients with Down syndrome, intracardiac communications and elevated pulmonary arteriolar resistance presented early in life. Both patients had significant stenosis of pulmonary veins. The progressive nature of the stenosis is illustrated in one patient. Pulmonary venous stenosis in Down syndrome has been recorded only twice before in the literature, ...
Gould K L - - 1992
This study is a randomized, controlled, blinded, arteriographic trial to determine the effects of a low-cholesterol, low-fat, vegetarian diet, stress management and moderate aerobic exercise on geometric dimensions, shape and fluid dynamic characteristics of coronary artery stenoses in humans. Complex changes of different primary stenosis dimensions in opposite directions or ...
Kessler R M - - 1992
Pulmonary artery sling is an unusual anomaly. The results of surgical therapy have been unsatisfactory in the past because of poor long-term left pulmonary artery patency and failure to address concomitant primary tracheobronchial stenoses. Refinement of suture materials and microsurgical techniques have allowed earlier surgical treatment of tracheal stenosis and ...
Mack W J - - 1992
The Cholesterol Lowering Atherosclerosis Study, a randomized angiographic clinical trial, demonstrated the beneficial effect of niacin/colestipol plus diet therapy on coronary atherosclerosis. Outcome was determined by panel-based estimates (viewed in both still and cine modes) of percent stenosis severity and change in native artery and bypass graft lesions. Computer-based quantitative ...
Porter R W - - 1992
The pathophysiology of neurogenic claudication is not well understood. It is generally believed that stenosis of the central vertebral canal is significant, but some believe that it is root canal stenosis or stenosis of the foramen that is important, not pathology in the central canal. There are, however, clinical anomalies ...
Balkin J - - 1992
Computer-assisted videodensitometry has been shown to be a reliable and reproducible method of measuring absolute and relative coronary narrowings. Using a commercially available analyzer (Vanguard XR70) we confirmed intra- and interobserver reproducibilities in 34 narrowings in 9 patients. Analyses were performed on normal area and diameter, stenotic area and diameter, ...
Agrawal S - - 1991
Fifty one angiographically proved cases of tetralogy of Fallot (TOF) in the age group of 5-50 years were analysed retrospectively for the level(s) of right ventricular outflow tract (RVOT) obstruction. Mean age was 18.1 +/- 11 yrs. Subvalvular stenosis was found to be the commonest site of RVOT obstruction in ...
Stoddard M F - - 1991
To determine if aortic stenosis severity could be accurately measured by two-dimensional transesophageal echocardiography (TEE), 62 adult subjects (mean age 66 +/- 12 years) with aortic stenosis had their aortic valve area (AVA) determined by direct planimetry using TEE, and with the continuity equation using combined transthoracic Doppler and two-dimensional ...
Fleming R M - - 1991
In part 1 of a three-part study, 14 novice readers and 6 experienced cardiologists interpreted phantom images of known stenosis severity. No difference between the interpretations of experienced and novice readers was detectable. Visual estimates of "moderately" severe stenosis were 30% higher than actual percent diameter stenosis. In part 2 ...
Dickson C S - - 1991
An arteriotomy is a commonly used surgical technique. Either a transverse or a longitudinal incision can be made, but no study has been done to determine if one technique results in more stenosis or flow disturbance than the other. Six-millimeter arteriotomies were made on the carotid and femoral arteries of ...
Yasuda I - - 1991
If not all of the right ventricular outflow tract obstruction (RVOTO) is removed in the operation for pulmonary stenosis, high right ventricular pressure can sometimes occur afterward. However, it is not easy to assess the amount of RVOTO that is to be removed, and there is no quantifiable method for ...
Goldman L - - 1991
To analyze the relationship among characteristics of buits, degree of underlying stenosis, and neurologic symptom complexes, the authors studied 157 patients with bruits undergoing digital subtraction angiography. Symptom status assignment (definite lateralizing, possible lateralizing, vertebrobasilar, diffuse, and asymptomatic) and cervical auscultation for location, duration, and other bruit characteristics were performed ...
Parsons D - - 1991
The consultants concur that distal tracheal stenosis is a challenging problem in the pediatric patient but don't all agree on the presentation or management. Drs. Cotton and Crysdale agree that these children are usually seen with biphasic stridor. Dr. Parsons believes that biphasic stridor is not particularly common but inspiratory ...
Choi J Y - - 1991
Retrospective echocardiographic review identified 58 consecutive infants and children with fixed subaortic stenosis. Mean (SD) age at diagnosis was 4.8 (3.6) years (range two days to 14.7 years), and diagnosis occurred in infancy in eight. Associated cardiac abnormalities were present in 41 (71%) whereas fixed subaortic stenosis was an isolated ...
Patt M V - - 1991
The diagnosis of cor triatriatum in an adult was made from routine two-dimensional transthoracic echocardiography. The findings of aliasing and turbulence in the roof of the left atrium suggested pulmonary venous stenosis. A transesophageal echocardiogram defined both the hemodynamic features of nonobstructing cor triatriatum and the presence of isolated pulmonary ...
Poindexter J M JM - - 1991
We retrospectively compared the results of duplex scanning (DS) with contrast angiography (CAN) in the evaluation of 119 patients whose 238 carotid arteries were evaluated by both methods within a four-week period. The results of all patients were then categorized by two different definitions of severity of stenosis. Category A ...
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