33 resultados para Stenosis Severity

em University of Queensland eSpace - Australia


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Background: False-negative interpretations of do-butamine stress echocardiography (DSE) may be associated with reduced wall stress. using measurements of contraction, we sought whether these segments were actually ischemic but unrecognized or showed normal contraction. Methods. We studied 48 patients (29 men; mean age 60 +/- 10 years) with normal regional function on the basis of standard qualitative interpretation of DSE. At coronary angiography within. 6 months of DSE, 32 were identified as having true-negative and 16 as having false-negative results of DSE. Three apical views were used to measure regional function with color Doppler tissue, integrated backscatter, and strain rate imaging. Cyclic variation of integrated backscatter was measured in 16 segments, and strain rate and peak systolic strain was calculated in 6 walls at rest and peak stress. Results. Segments with false-negative results of DSE were divided into 2 groups with and without low wall stress according to previously published cut-off values. Age, sex, left ventricular mass, left ventricular geometric pattern, and peak workload were not significantly different between patients with true and false-negative results of DSE. Importantly, no significant differences in cyclic variation and strain parameters at rest and peak stress were found among segments with true-and false-negative results of DSE with and without low wall stress. Stenosis severity had no influence on cyclic variation and strain parameters at peak stress. Conclusions: False-negative results of DSE reflect lack of ischemia rather than underinterpretation of regional left ventricular function. Quantitative markers are unlikely to increase the sensitivity of DSE.

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Impaired coronary flow reserve is widely reported in diabetes mellitus (DM) but its effect on myocardial contrast echocardiography (MCE) is unclear. We sought to identify whether DM influences the accuracy of qualitative and quantitative assessment of coronary artery disease (CAD) using MCE in 83 patients who underwent coronary angiography (60 men, 27 with DM; 56 +/- 11 years;). Destruction replenishment imaging was performed at rest and after combined dipyridamole-exercise stress testing. Ischemia was identified by the development of new wall motion abnormalities, qualitative MCE (new perfusion defects apparent 1 second after flash during hyperemia), and quantitative MCE (myocardial blood flow reserve < 2.0 in the anterior circulation). Qualitative and quantitative assessment of perfusion was feasible in 100% and 92% of patients, respectively. Significant left anterior descending coronary stenosis (> 50% by quantitative angiography) was present in 28 patients (including 8 with DM); 55 patients had no CAD (including 19 with DM). The myocardial blood flow reserve was reduced in patients with coronary stenosis compared with those with no CAD (1.6 +/- 1.1 vs 3.8 +/- 2.5, p < 0.001). Among patients with no CAD, those with DM had an impaired flow reserve compared with control patients without DM (2.4 +/- 1.0 vs 4.5 +/- 2.8, p = 0.003). In conclusion, DM significantly influenced the quantitative, but not the qualitative, assessment of MCE, with a marked reduction in specificity in patients with DM. (c) 2005 Elsevier Inc. All rights reserved.

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Background: Qualitative interpretation of myocardial contrast echocardiography (MCE) improves the accuracy of wall-motion analysis for assessment of coronary artery disease (CAD). We examined the feasibility and accuracy of quantitative MCE for diagnosis of CAD. Methods: Dipyridamole/exercise stress MCE (destruction-replenishment protocol with real-time imaging) was performed in 90 patients undergoing quantitative coronary angiography, 48 of whom had significant (> 50%) stenoses. MCE was repeated with exercise alone in 18 patients. Myocardial blood flow (A*beta) was obtained from blood volume (A) and time to refill (beta). Results: Quantification of flow reserve was feasible in 88%. The mean A*beta reserve in the anterior wall was significantly impaired for patients with left anterior descending coronary artery disease (n = 28) compared with those with no disease (1.6 +/- 1.2 vs; 4.0 +/- 2.5, P <=.001). This reflected impaired beta reserve, with no difference in the A reserve. Applying a receiver operating characteristic curve derived cutoff of 2.0 for A*beta reserve, quantitative MCE was 76% sensitive and 71% specific for the diagnosis of significant left anterior descending coronary artery stenosis. Posterior circulation results were similar, with 78% sensitivity and 59% specificity for detection of posterior CAD. Overall, quantitative MCE was similarly sensitive to qualitative approach for diagnosis of CAD (88% vs 93%), but with lower specificity (52% vs 65%, P =.07). In 18 patients restudied with pure exercise stress, the mean myocardial blood flow reserve was less than after combined stress (2.1 +/- 1.6 vs 3.7 +/- 1.9, P =.01). Conclusion: Quantitative MCE is feasible for the diagnosis of CAD with dipyridamole/exercise stress. Dipyridamole prolongs postexercise hyperemia, augmenting the degree of hyperemia at the time of imaging.

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Objective: To use quantitative myocardial contrast echocardiography (MCE) and strain rate imaging (SRI) to assess the role of microvascular disease in subclinical diabetic cardiomyopathy. Methods: Stress MCE and SRI were performed in 48 patients (22 with type II diabetes mellitus (DM) and 26 controls), all with normal left ventricular systolic function and no obstructive coronary disease by quantitative coronary angiography. Real-time MCE was acquired in three apical views at rest and after combined dipyridamole-exercise stress. Myocardial blood flow (MBF) was quantified in the 10 mid- and apical cardiac segments at rest and after stress. Resting peak systolic strain rate (SR) and peak systolic strain (epsilon) were calculated in the same 10 myocardial segments. Results: The DM and control groups were matched for age, sex and other risk factors, including hypertension. The DM group had higher body mass index and left ventricular mass index. Quantitative SRI analysis was possible in all patients and quantitative MCE in 46 (96%). The mean e, SR and MBF reserve were all significantly lower in the DM group than in controls, with diabetes the only independent predictor of each parameter. No correlation was seen between MBF and SR (r = -0.01, p = 0.54) or between MBF and epsilon ( r = -0.20, p = 0.20). Conclusions: Quantitative MCE shows that patients with diabetes but no evidence of obstructive coronary artery disease have impaired MBF reserve, but abnormal transmural flow and subclinical longitudinal myocardial dysfunction are not related.

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This study investigated the role of both negative and positive cognitions in predicting panic severity in an international sample of patients diagnosed with panic disorder (with and without agoraphobia). One hundred and fifty-nine patients were administered the Brief Bodily Sensations Interpretation Questionnaire (BBSIQ), the Self-efficacy to Control Panic Attacks Questionnaire, and the Panic and Agoraphobia Scale (PAS) prior to receiving treatment. Regression analyses indicated that both catastrophic misinterpretation of bodily sensations and panic self-efficacy independently predicted panic severity. The influence of panic self-efficacy upon panic severity remained significant even after controlling for the presence or absence of agoraphobia. There was no evidence to suggest a moderating relationship between the two cognitive factors. Results are discussed in terms of the need to consider both negative and positive cognitions in cognitive accounts of panic disorder. (C) 2002 Elsevier Science Inc. All rights reserved.

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Objectives. Pulsatile tinnitus is a rare and often disabling condition. Pulsatile tinnitus sometimes occurs in patients with severe atherosclerotic carotid stenosis. It is uncertain whether carotid endarterectomy (CEA) relieves pulsatile tinnitus in patients with severe carotid stenosis. Design, Materials and Methods. This is a retrospective study of 14 patients with pulsatile tinnitus who underwent CEA. Demographic and clinical features and pre-operative duplex results were recorded. Operative results in this group were assessed. Results. CEA relieved symptoms of pulsatile tinnitus in 10 out of 14 cases (70%). Of 10 patients that had lateralisable tinnitus and ipsilateral surgery, 9 (90%) reported symptomatic improvement. Conclusions. CEA is effective in improving pulsatile tinnitus in patients with unilateral symptoms and severe ipsilateral carotid stenosis.

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Background. The development of therapeutic interventions to prevent progressive valve damage is more likely to limit the progression of structural damage to the aortic valve with normal function (aortic sclerosis [ASC]) than clinically apparent aortic stenosis. Currently, the ability to appreciate the progression of ASC is compromised by the subjective and qualitative evaluation of sclerosis severity. Methods: We sought to reveal whether the intensity of ultrasonic backscatter could be used to quantify sclerosis severity in 26 patients with ASC and 23 healthy young adults. images of the aortic valve were obtained in the parasternal long-axis view and saved in raw data format. Six square-shaped 11 X 11 pixel regions of interest were placed on the anterior and posterior leaflets, and calibrated backscatter values were obtained by subtracting the regions of interest in the blood pool from the averaged backscatter values obtained from the leaflets. Results. Mean ultrasonic backscatter values for sclerotic valves exceeded the results in normal valve tissue (16.3 +/- 4.4 dB vs 9.8 +/- 3.3 dB, P < .0001). Backscatter values were greater (22.0 +/- 3.5 dB) in a group of 6 patients with aortic stenosis. Within the sclerosis group, the magnitude of backscatter was directly correlated (P < .05) with a subjective sclerosis score, and with transvalvular pressure gradient. mean reproducibility was 2.4 +/- 1.8 dB (SD) between observers, and 2.3 +/- 1.7 dB (SD) between examinations. Conclusion: Measurement of backscatter from the valve leaflets of patients with ASC may be a feasible means of following the progression and treatment response of aortic sclerosis.

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Mungbean (Vigna radiata L.), as a dryland grain legume, is exposed to varying timing and severity of water deficit, which results in variability in grain yield, nitrogen accumulation and grain quality. In this field study, mungbean crops were exposed to varying timing and severity of water deficit in order to examine: (1) contribution of the second flush of pods to final grain yield with variable timing of relief from water deficit, (2) the sensitivity to water deficit of the accumulation of biomass and nitrogen (N) and its partitioning to grain, and (3) how the timing of water deficit affects the pattern of harvest index (HI) increase through pod filling. The results showed that the contribution of the second flush to final yield is highly variable (1-56%) and can be considerable, especially where mid-season stress is relieved at early pod filling. The capacity to produce a second flush of pods did not compensate fully for yield reduction due to water stress. Relief from mid-season stress also resulted in continued leaf production, N-2 fixation and vegetative biomass accumulation during pod filling. Despite the wide variation in the degree of change in vegetative biomass and N during pod filling, there were strong relationships between grain yield and net-above-ground biomass at maturity, and grain N and above-ground N at maturity. Only in the extreme situations were HI and nitrogen HI affected noticeably. In those treatments where there was a large second flush of pods, there was a pronounced biphasic pattern to pod number production, with HI also progressing through two distinct phases of increase separated by a plateau. The proportion of grain yield contributed to by biomass produced before pod filling varied from 0 to 61% with the contribution greatest under terminal water deficit. There was a larger effect of water deficit on N accumulation, and hence N-2 fixation, than on biomass accumulation. The study confirmed the applicability of a number of long-standing physiological concepts to the analysis of the effect of water deficit on mungbean, but also highlighted the difficulty of accounting for timing effects of water deficit where second flushes of pods alter canopy development, biomass and yield accumulation, and N dynamics. Crown Copyright (C) 2003 Published by Elsevier B.V. All rights reserved.

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The manner in which elements of clinical history, physical examination and investigations influence subjectively assessed illness severity and outcome prediction is poorly understood. This study investigates the relationship between clinician and objectively assessed illness severity and the factors influencing clinician's diagnostic confidence and illness severity rating for ventilated patients with suspected pneumonia in the intensive care unit (ICU). A prospective study of fourteen ICUs included all ventilated admissions with a clinical diagnosis of pneumonia. Data collection included pneumonia type - community-acquired (CAP), hospital-acquired (HAP) and ventilator-associated (VAP), clinician determined illness severity (CDIS), diagnostic methods, clinical diagnostic confidence (CDC), microbiological isolates and antibiotic use. For 476 episodes of pneumonia (48% CAP, 24% HAP, 28% VAP), CDC was greatest for CAP (64% CAP, 50% HAP and 49% VAP, P < 0.01) or when pneumonia was considered life-threatening (84% high CDC, 13% medium CDC and 3% low CDC, P < 0.001). Life-threatening pneumonia was predicted by worsening gas exchange (OR 4.8, CI 95% 2.3-10.2, P < 0.001), clinical signs of consolidation (OR 2.0, CI 95% 1.2-3.2, P < 0.01) and the Sepsis-Related Organ Failure Assessment (SOFA) Score (OR 1.1, CI 95% 1.1-1.2, P < 0.001). Diagnostic confidence increased with CDIS (OR 163, CI 95% 8.4-31.4, P < 0.001), definite pathogen isolation (OR 3.3, CI 95% 2.0-5.6) and clinical signs of consolidation (OR 2.1, CI 95% 1.3-3.3, P = 0.001). Although the CDIS, SOFA Score and the Simplified Acute Physiologic Score (SAPS II) were all associated with mortality, the SAPS II Score was the best predictor of mortality (P = 0.02). Diagnostic confidence for pneumonia is moderate but increases with more classical presentations. A small set of clinical parameters influence subjective assessment. Objective assessment using SAPS II Scoring is a better predictor of mortality.

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This study examined the differential role of negative and positive cognitions in mediating treatment outcome in CBT for Panic Disorder through comparison of a Standard CBT (n = 36) versus a Waitlist Condition (n = 24). Regression analyses indicated that, relative to the Waitlist Condition, patients in the Standard CBT condition reported significantly greater shifts both towards higher panic self-efficacy and lower catastrophic misinterpretation of bodily sensations during treatment, as well as a significantly lower level of panic severity at posttreatment. Changes in catastrophic misinterpretation of bodily sensations and panic self-efficacy contributed significantly more to prediction of panic severity than did assignment to either Standard CB T or a Waitlist Condition. Results are discussed in terms of the importance of including both negative and positive cognitions in demonstrating cognitive mediation.

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In recent years, the multiparametric approach for evaluating perceptual rating of voice quality has been advocated. This study evaluates the accuracy of predicting perceived overall severity of voice quality with a minimal set of aerodynamic, voice range profile (phonetogram), and acoustic perturbation measures. One hundred and twelve dysphonic persons (93 women and 19 men) with laryngeal pathologies and 41 normal controls (35 women and six men) with normal voices participated in this study. Perceptual severity judgement was carried out by four listeners rating the G (overall grade) parameter of the GRBAS scale.(1) The minimal set of instrumental measures was selected based on the ability of the measure to discriminate between dysphonic and normal voices, and to attain at least a moderate correlation with perceived overall severity. Results indicated that perceived overall severity was best described by maximum phonation time of sustained /a/, peak intraoral pressure of the consonant-vowel /pi/ strings production, voice range profile area, and acoustic jitter. Direct-entry discriminant function analysis revealed that these four voice measures in combination correctly predicted 67.3% of perceived overall severity levels.

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Fusarium wilt of banana is a potentially devastating disease throughout the world. Options for control of the causal organism, Fusarium oxysporum f.sp. cubense (Foc) are limited. Suppressive soil sites have previously been identified where, despite the presence of Foc, Fusarium wilt does not develop. In order to understand some aspects of this disease suppression, endophytic Fusarium oxysporum isolates were obtained from banana roots. These isolates were genetically characterized and compared with an isolate of Fusarium oxysporum previously identified as being capable of suppressing Fusarium wilt of banana in glasshouse trials. Three additional isolates were selected for glasshouse trials to assess suppression of Fusarium wilt in two different cultivars of banana, Cavendish and Lady Finger. One isolate (BRIP 29089) was identified as a potential biocontrol organism, reducing the disease severity of Fusarium wilt in Lady Finger and Cavendish cultivars. Interestingly, one isolate (BRIP 45952) increased Fusarium wilt disease severity on Cavendish. The implications of an isolate of Fusarium oxysporum, non-pathogenic on banana, increasing disease severity and the potential role of non-pathogenic isolates of Fusarium oxysporum in disease complexes are discussed. (c) 2006 Published by Elsevier Ltd on behalf of The British Mycological Society.

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Objectives: To compare the general psychopathology in an eating disorders (ED) and a child mental health Outpatient sample and investigate the implications of comorbidity on psychological and physical measures of ED severity. Methods: One hundred thirty-six children and adolescents with a DSM-IV ED diagnosis were compared with age- and gender-matched controls. Measures included the Eating Disorders Examination and the Child Behavior Checklist. Results: The ED group had lower general and externalizing psychopathology scores and no difference in internalizing (anxiety-depression) symptoms. Of the anorexia nervosa group, 49% experienced comorbid psychopathology. This group had significantly higher ED psychopathology, longer duration of illness, and more gastrointestinal symptoms, but no difference in malnutrition status. Eating disorders not otherwise specified (EDNos) group measures were less influenced by comorbidity status. Conclusions: Anxiety-depressive symptoms are very common in children and adolescents with EDs. Comorbidity status influences illness severity, especially in the anorexia nervosa group. The management implications of these findings are discussed. (c) 2006 Elsevier Inc. All rights reserved.