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41.
BACKGROUND: The reduction of coronary flow reserve (CFR) found in arterial hypertension may be due to changes in afterload, left ventricular (LV) structure, and metabolic factors. Also, insulin-like growth factor-1 (IGF-1) may be associated with the magnitude of CFR in relation to its modulating action on cardiac and endothelial function. METHODS: A total of 44 newly diagnosed, untreated hypertensive patients, who were free of diabetes mellitus and coronary artery disease, underwent M-mode analysis, second-harmonic Doppler echocardiographic assessment of CFR (dipyridamole infusion 0.56 mg/kg intravenously in four patients), determination of circulating free IGF-1, and insulin resistance. Based on CFR levels, hypertensive subjects were divided into two groups: 18 with normal CFR (> or = 2) and 26 with impaired CFR (<2). RESULTS: Patients with normal CFR had lower diastolic blood pressure, heart rate, and LV mass index but higher free circulating IGF-I than patients with reduced CFR (P < .001). Insulin resistance was not significantly different between the two groups. In a first multilinear regression analysis that included demographic and echocardiographic variables, insulin resistance was independently associated with CFR (standardized beta coefficient = -0.31, P < .05) in the overall population. However, in a subsequent model which included also IGF-1, the relationship between insulin resistance and CFR disappeared, whereas IGF-1 was the main independent determinant of CFR (beta = 0.51, P < .0002). CONCLUSIONS: Free IGF-1 circulating levels are independently associated with CFR in hypertensive individuals free of overt coronary artery disease. A possible beneficial effect exerted by IGF-1 on coronary blood flow may be supposed in arterial hypertension.  相似文献   
42.
PURPOSE: The use of electrophysiologic studies (EPS) for the localization of accessory atrioventricular connections in Wolff-Parkinson-White syndrome (WPW) requires accurate evaluation of the site of bypass tract insertion. Doppler myocardial imaging (DMI) is a new ultrasound technique that allows the detection of abnormal and early regional myocardial depolarization. The purpose of this study was to identify an abnormal pathway site in WPW patients. METHODS: Twenty-one patients with ventricular preexcitation were studied by DMI. Two-dimensional color DMI, velocity maps, acceleration maps, and pulsed-wave applications were used. A subsequent diagnostic EPS was performed. The results of EPS were taken as the gold standard diagnostic procedure. Radiofrequency catheter ablation therapy was then performed on all patients. RESULTS: The anomalous pathway was detected by DMI in 16 (76%) of 21 patients (9 [90%] of 10 with left pathways and 7 [64%] of 11 with right pathways), with respect to results of the EPS. Pathway detection was better with pulsed-wave DMI (76%) with its higher temporal resolution as compared with M-mode velocity map (57%) and acceleration map (47%). In most of the patients with successful radiofrequency ablation, an immediate resolution of the abnormal ventricular depolarization occurred and was detectable by DMI. CONCLUSIONS: Our findings demonstrate the feasibility of DMI to assess the early ventricular contraction associated with atrioventricular accessory pathways. Therefore, DMI appears to be a clinically useful adjunct to noninvasive evaluation of abnormal myocardial depolarization in WPW and to evaluate the results after radiofrequency ablation, even though its accuracy is considerably better for left-sided accessory pathways than for right-sided ones.  相似文献   
43.
Background and purposePrognostic risk factors of haemorrhagic stroke are not yet fully identified. This study investigated clinical factors leading to poor outcome at three months in patients with intracerebral haemorrhage (ICH) in order to better understand the role of clinical features in prognostic evaluation.Subjects and methodsThis was a prospective cohort study on patients having ICH admitted to two Italian hospitals (the Stroke Units at “Ospedale Santa Maria della Misericordia“, Perugia and “Ospedale C. Poma“, Mantua) between January 1, 2006 and June 30, 2010.ResultsA total of 470 consecutive ICH patients (mean age 73.89 ± 13.02 years) were included and of these, 241 (51.1%) were males. At three months, 293 (62.3%) patients had poor outcome including 133 (27.6%) deaths. The resulting significant predictors of poor outcome from univariate analysis included: age, NIH Stroke Scale Score (NIHSSS) at admission, hyperglycaemia and the presence of atrial fibrillation (AF). These variables were confirmed in logistic regression analyses as being independent predictors of disability: age (OR 1.04 95% CI, 1.02–1.07, p = 0.0001), AF (OR 3.18 95% CI, 1.12–9.05 p = 0.03) and NIHSSS (OR 1.38 95% CI, 1.28–1.48, p = 0.0001), while elderly age (OR 1.10 95% CI, 1.06–1.14, p  0.0001) and high NIHSSS (OR 1.25 95% CI, 1.19–1.31, p  0.0001) resulted being independent predictors of mortality.ConclusionsThis study found that severity of ICH, elderly age and AF were independent predictors of poor outcome in ICH patients at three months. Thereby, this highlights the importance of understanding the roles of clinical features in ICH prognostic evaluation.  相似文献   
44.
45.
Non-invasive Doppler ultrasonographic study of cerebral arteries [transcranial Doppler(TCD)] has been extensively applied on both outpatient and inpatient settings. It is performed placing a low-frequency(≤ 2 MHz) transducer on the scalp of the patient over specific acoustic windows, in order to visualize the intracranial arterial vessels and to evaluate the cerebral blood flow velocity and its alteration in many different conditions. Nowadays the most widespread indication for TCD in outpatient setting is the research of right to left shunting, responsable of so called "paradoxical embolism", most often due to patency of foramen ovale which is responsable of the majority of cryptogenic strokes occuring in patients younger than 55 years old. TCD also allows to classify the grade of severity of such shunts using the so called "microembolic signal grading score". In addition TCD has found many useful applications in neurocritical care practice. It is useful on both adults and children for day-to-day bedside assessment of critical conditions including vasospasm in subarachnoidal haemorrhage(caused by aneurysm rupture or traumatic injury), traumatic brain injury, brain stem death. It is used also to evaluate cerebral hemodynamic changes after stroke. It also allows to investigate cerebral pressure autoregulation and for the clinical evaluation of cerebral autoregulatory reserve.  相似文献   
46.
To understand the etiopathogenetic mechanisms of stroke and to target prevention, we need to know how risk factors differ among etiological subtypes. Our aims were to determine the different profile of risk factors for ischemic and hemorrhagic stroke subtypes in our cohort from the Perugia Hospital-Based Stroke Registry. We analyzed the characteristics and the different risk factors of 2,395 first-ever consecutive stroke patients admitted to the Perugia Hospitals in the period between January 1, 1998 and December 31, 2002. The prevalence of cerebrovascular risk factors in each stroke subtype was analyzed independently and compared with other subtypes of stroke pooled together by means of univariate analysis and logistic regression models. Hypertension occurred in 61% of patients; familial history of stroke in 41.6%; vascular disease in 27.2%; embolic heart disease in 22.3%; cigarette smoking in 21.6%. Different potentially modifiable risk factors profiles were identified for each ischemic subtype of stroke, while in hemorrhagic lobar stroke subtypes, only male gender was an independent risk factor.  相似文献   
47.
White matter (WM) tract damage was assessed in patients with the behavioral variant frontotemporal dementia (bvFTD) and the 3 primary progressive aphasia (PPA) variants and compared with the corresponding brain atrophy patterns. Thirteen bvFTD and 20 PPA patients were studied. Tract-based spatial statistics and voxel-based morphometry were used. Patients with bvFTD showed widespread diffusion tensor magnetic resonance imaging (DT MRI) abnormalities affecting most of the WM bilaterally. In PPA patients, WM damage was more focal and varied across the 3 syndromes: left frontotemporoparietal in nonfluent, left frontotemporal in semantic, and left frontoparietal in logopenic patients. In each syndrome, DT MRI changes extended beyond the topography of gray matter loss. Left uncinate damage was the best predictor of frontotemporal lobar degeneration diagnosis versus controls. DT MRI measures of the anterior corpus callosum and left superior longitudinal fasciculus differentiated bvFTD from nonfluent cases. The best predictors of semantic PPA compared with both bvFTD and nonfluent cases were diffusivity abnormalities of the left uncinate and inferior longitudinal fasciculus. This study provides insights into the similarities and differences of WM damage in bvFTD and PPA variants. DT MRI metrics hold promise to serve as early markers of WM integrity loss that only at a later stage may be detectable by volumetric measures.  相似文献   
48.
IntroductionHypertensive heart disease is manifested by structural and functional adaptations of the myocardium that lead to heart failure, mainly diastolic, especially in women older than 65 years.ObjectivesThe ejection fraction of the left ventricle, which is considered an image of systolic function, represents instead an indicator less closely related to the complex ventricular remodeling, responsible for the variety of clinical aspects of hypertensive heart disease. Above all, it seems to be incorrect that the boundary between function “preserved” or “not preserved” is reflected only in the value of the ejection fraction of 50%. Anatomical and functional considerations of the structure of the ventricles and of the way in which they contract and release, suggest a need to reconsider the excessive value that is currently ascribed to this parameter.ConclusionsModern echocardiography with tissue Doppler and speckle tracking, may provide the means to objectively evaluate and quantify this new point of view.  相似文献   
49.
Evaluation of: Pan A, Okereke OI, Sun Q et al. Depression and incident stroke in women. Stroke 42(10), 2770-2775 (2011). In the Nurses' Health Study, 80,574 women aged between 54 and 79 years, without a history of stroke, were followed-up from 2000 to 2006. In this cohort, depressive symptoms were assessed at multiple time points utilizing the Mental Health Index score (1992, 1996 and 2000), and clinically significant depressive symptoms were defined as a score ≤ 52. A survey was carried out regarding antidepressant medication use biennially beginning in 1996, and physician-diagnosed depression was reported biennially from 2000. During this 6-year follow-up, 1033 incident strokes were documented. Having a history of depression was associated with an increased risk for total stroke, as well as the use of antidepressant medications with or without history of depression.  相似文献   
50.
This study sought to evaluate global and regional left ventricular (LV) function before and early after device closure of atrial septal defects (ASDs) in patients with normal pulmonary pressure. Global LV diastolic function was unaffected by ASD closure. An improvement in global LV systolic function at rest resulted in an increase in stroke volume at rest. Nevertheless, total cardiac output did not change after the procedure, because of a decrease in heart rate at rest counterbalancing the increase in stroke volume. Thus, lateral and inferior LV regional systolic function were preserved after device implantation. Moreover, no changes in regional LV diastolic function were highlighted during the study.  相似文献   
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