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《Journal of Cardiovascular Computed Tomography》2014,8(1):67-76
BackgroundIn transcatheter aortic valve replacement, prosthesis oversizing is essential to prevent paravalvular regurgitation. However, the estimated extent of oversizing strongly depends on the measurement used for annular sizing.PurposeThe aim was to investigate the influence of geometrical parameters for calculation of relative oversizing in transcatheter aortic valve replacement, reported as percentage in relation to the native annulus size, to standardize reporting.MethodsElectrocardiogram-gated cardiac dual-source CT data of 130 consecutive patients with severe aortic stenosis (mean age, 81 ± 8 years; 56 men; mean aortic valve area, 0.67 ± 0.18 cm2) were included. Aortic annulus dimensions were quantified by means of planimetry that yielded area and perimeter at the level of the basal attachment points of the aortic cusps during systole. Area- and perimeter-derived diameters were calculated as DA = 2 × √(A/π) and DP = P/π. Hypothetical prosthesis sizing was based on DA (23-mm prosthesis for 19–22 mm; 26-mm prosthesis for 22–25 mm; 29-mm prosthesis for 25–28 mm). Relative oversizing for hypothetical prosthesis selection was calculated as percentage in relation to the native annulus size.ResultsMean annulus area was 492.12 ± 94.9 mm2 and mean perimeter was 80.1 ± 7.6 mm. DP was significantly larger than DA (25.5 ± 2.4 mm vs 24.9 ± 2.4 mm; P < .001). Mean maximum diameter was 28.1 ± 3.0 mm and mean minimal diameter was 22.8 ± 2.4 mm. Calculated eccentricity index [EI = 1 − minimal diameter/maximum diameter)] was 0.19 ± 0.06. Difference between DP and DA correlated significantly with EI (r = 0.67; P < .001). Relative oversizing was 10.2% ± 3.8% and 21.6% ± 8.4% by DA and area, and 7.8% ± 3.9% by both DP and perimeter.ConclusionFor planimetric assessment of aortic annulus dimensions with CT, the percentage oversizing calculated strongly depends on the geometrical variable used for quantifying annular dimensions. Standardized nomenclature seems warranted for comparison of future studies. 相似文献
225.
Konstantina Apostolopoulou Sabine Gerum Katrin Merkle Sebastian Schulz Evelyn Fischer 《The world journal of biological psychiatry》2014,15(1):26-35
Objective. The renin-angiotensin-aldosterone-system (RAAS) has gained increasing attention in the investigation of the pathogenesis of depression. Primary hyperaldosteronism (PA) is associated with a marked aldosterone excess. Prior studies on PA describe an increased prevalence of anxiety and sub-threshold depressive symptoms in these patients. Methods. In a cross-sectional exploratory study we investigated 132 patients with PA. Twenty-seven patients were studied before initiation of specific treatment (U = untreated), 56 were studied 5.4 years after initiation of mineralocorticoid antagonist treatment (MRA) and 49 patients were studied 4.3 years after unilateral adrenalectomy (ADX). GAD-7 and PHQD self-rating questionnaires were used to assess symptoms for anxiety and depression. Results. No significant difference was found between the three investigated groups. A higher prevalence for depression and anxiety compared to the normal population was found. Women of all groups had higher mean values compared to men, for depression in untreated patients this difference was found to be significant. Correlations between the psychopathology and hormones were only found for renin. Plasma renin concentration correlated significantly with anxious symptoms of untreated females. Conclusions. This study supports the RAAS to be involved in the pathogenesis of depression as patients with PA seem to be more depressive and anxious compared to the normal population. Gender differences in the regulation of the RAAS seem to be apparent, as females were more affected by the dysregulation than males. 相似文献
226.
李晓琴 《中国航天工业医药》2013,(6):45-46
目的分析子宫动脉栓塞术治疗子宫肌瘤的疗效和安全性。方法选择2010年7月~2012年3月我院收治的137例子宫肌瘤患者为研究对象,应用随机数字表法将子宫肌瘤患者分为治疗组和对照组,对照组采用传统激素治疗(61例),治疗组则在月经来潮干净后1周内采用子宫动脉栓塞术(76例)。随访半年,比较两组患者的临床疗效和安全性。结果治疗组总有效率(89.48%)显著高于对照组(52.46%),χ2=23.5185,P〈0.01。治疗组失败率与对照组相差不大(χ2=1.5021,P〉0.05)。结论子宫动脉栓塞术与传统激素治疗相比具有高效、微创、恢复时间短等优点。 相似文献
227.
李迎 《中国现代医学杂志》2012,22(19):104-106
目的 探讨高血压病患者动脉弹性功能变化情况及其影响因素.方法 应用脉搏波速度自动测量系统对62例健康人和232例高血压病患者进行颈动脉-股动脉脉搏波速度(CFPWV)检测,并分析与收缩压(SBP)、舒张压(DBP)、平均压(MBP)、脉压(PP)、体重指数、年龄等指标的相关性.结果 高血压病患者的CFPWV显著高于健康人(P<0.01).高血压病患者CFPWV显著高于健康人(P<0.01),并与年龄、SBP、DBP、MBP、PP呈显著的负相关(P<0.01).结论 高血压病患者的动脉弹性明显降低,检测CFPWV可观察动脉早期功能改变,对临床早期干预治疗具有重要意义. 相似文献
228.
Nasim Maleki Jennifer Brawn Gabi Barmettler David Borsook Lino Becerra 《NMR in biomedicine》2013,26(6):664-673
The majority of functional MRI studies of pain processing in the brain use the blood oxygenation level‐dependent (BOLD) imaging approach. However, the BOLD signal is complex as it depends on simultaneous changes in blood flow, vascular volume and oxygen metabolism. Arterial spin labeling (ASL) perfusion imaging is another imaging approach in which the magnetically labeled arterial water is used as an endogenous tracer that allows for direct measurement of cerebral blood flow. In this study, we assessed the pain response in the brain using a pulsed‐continuous arterial spin labeling (pCASL) approach and a thermal stimulation paradigm. Using pCASL, response to noxious stimulation was detected in somatosensory cortex, anterior cingulate cortex, anterior insula, hippocampus, amygdala, thalamus and precuneus, consistent with the pain response activation patterns detected using the BOLD imaging approach. We suggest that pCASL is a reliable alternative for functional MRI pain studies in conditions in which blood flow, volume or oxygen extraction are altered or compromised. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
229.