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目的调查分析Stanford A型主动脉夹层术后肾脏功能损伤(AKI)的危险因素,为临床降低肾脏功能损伤并发率对策提供支持。方法收集2017年1月—2019年12月医院心血管外科确诊且顺利行A型主动脉夹层手术的179例患者为研究对象,均由同组外科医师和麻醉医师实施手术,术后进入ICU监测治疗。根据术后早期是否存在AKI,将发生AKI 60例设为病例组,未发生AKI 119例设为对照组。分析发生AKI高危因素。结果经过多因素Logistics回归分析显示,年龄(OR=2.396)、双侧肾脏灌注欠佳(OR=8.725)、BMI值(OR=3.454)、监测膀胱温度(OR=4.180)、CPB时长(OR=2.165)、术中红细胞输注(OR=2.291)均为此类手术患者发生AKI独立危险因素(P<0.05)。结论年龄、BMI值、双侧肾脏灌注欠佳、CPB、监测膀胱温度、术中红细胞输注均为影响A型主动脉夹层术后AKI的独立相关因素,临床护士应针对上述分析制定个体化针对方案以降低术后AKI发生风险。  相似文献   
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PurposeTo evaluate the feasibility, safety, and effectiveness of N-butyl cyanoacrylate (NBCA) embolization for the treatment of aortic dissection.Materials and MethodsIn this single-center retrospective study conducted from February 2003 to June 2019, NBCA embolization of an aortic false lumen was attempted in 12 patients (median age, 59 y; range, 41–68 y) and thoracic endovascular aortic repair (TEVAR) was performed in 53 patients (median age, 59 y; range, 37–70 y) for aortic dissection with one or more indications of persisting pain, malperfusion, rupture or impending rupture, maximal aortic diameter ≥ 55 mm, and/or rapid aortic enlargement. The main exclusion criterion for embolization was the presence of fast blood flow in the aortic false lumen on aortography. The efficacy of NBCA embolization and TEVAR was compared by evaluating technical and clinical outcomes, repeat intervention–free survival (RFS), and overall survival (OS).ResultsTechnical success was achieved in 11 of the 12 patients treated with NBCA embolization (91.7%), and clinical success was achieved in 9 of these 11 (81.8%). No significant difference was found between embolization and TEVAR in clinical success rates (embolization, 81.8%; TEVAR, 84.9%; P = .409) or procedure-related complications (embolization, 1 patient [8.3%]; TEVAR, 4 patients [7.5%]; P = .701). In addition, embolization showed comparable 5-y RFS (embolization, 82.5% ± 9.3; TEVAR, 85.5% ± 4.8; P = .641) and 5-y OS (embolization, 100%; TEVAR, 95.4% ± 3.2; P = .744) rates to TEVAR.ConclusionsNBCA embolization of the false lumen in aortic dissection seems to be a safe and effective treatment modality for the closure of false lumen in selected patients.  相似文献   
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Cerebral arterial pulsatility is strongly associated with cerebral small vessel disease and lacunar stroke yet its dependence on central versus local haemodynamic processes is unclear. In a population-based study of patients on best medical managment, 4–6 weeks after a TIA or non-disabling stroke, arterial stiffness and aortic systolic, diastolic and pulse pressures were measured (Sphygmocor). Middle cerebral artery peak and trough flow velocities and Gosling’s pulsatility index were measured by transcranial ultrasound. In 981 participants, aortic and cerebral pulsatility rose strongly with age in both sexes, but aortic diastolic pressure fell more with age in men whilst cerebral trough velocity fell more in women. There was no significant association between aortic systolic or diastolic blood pressure with cerebral peak or trough flow velocity but aortic pulse pressure explained 37% of the variance in cerebral arterial pulsatility, before adjustment, whilst 49% of the variance was explained by aortic pulse pressure, arterial stiffness, age, gender and cardiovascular risk factors. Furthermore, arterial stiffness partially mediated the relationship between aortic and cerebral pulsatility. Overall, absolute aortic pressures and cerebral blood flow velocity were poorly correlated but aortic and cerebral pulsatility were strongly related, suggesting a key role for transmission of aortic pulsatility to the brain.  相似文献   
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Sudden death due to anomalous aortic origin of a coronary artery is far less common among young children in the absence of exercise stress. This report describes the case of a 2-year-old boy with a lower respiratory tract infection who suffered sudden cardiac arrest in his bed at home. The autopsy revealed that the left coronary artery (LCA) originated from the right sinus of Valsalva with an acute angle takeoff and traveled between the aorta and the pulmonary trunk (an interarterial course). Upon histological examination, the LCA, before reaching its major branches, was located adjacent to the outside of the aortic wall without an intramural passage, and the arterial wall was composed almost exclusively of elastic fibers without media containing smooth muscle cells throughout the entire length of the abnormal running. Screening tests for respiratory virus infection detected enterovirus in the lung tissue. In association with an acute angle takeoff and interarterial course, the wall structure with highly abundant elastic fibers that are more flexible tissues among blood vessel components might suggest their vulnerability to compression during the great vessels’ systolic expansion in the sympathetic activation induced by the viral infection, leading to fatal myocardial ischemia without physical exertion.  相似文献   
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Objectives

This study applied advanced 4-dimensional flow magnetic resonance imaging processing to assess differences in aortic flow dynamics after valve sparing root replacement, with and without reconstruction of the Valsalva sinuses.

Methods

We enrolled patients after valve sparing root replacement with a straight tubular prosthesis (n = 10) or with a prosthesis with Valsalva neosinuses (n = 10); age-matched subjects without cardiovascular diseases served as controls (n = 10). 4-Dimensional flow magnetic resonance imaging acquisitions were performed on a 3.0T magnetic resonance imaging unit. In-house processing was used to segment the aortic lumen and extract the volumetric 4-dimensional flow velocity field. Velocity flow streamlines were computed to compare the amount of rotational flow and wall shear stress. Occurrence of abnormal wall shear stress (WSS) was estimated within the descending aorta of each surgical group.

Results

Physiologic-like sinus vortices were visible in the aortic root when using the prosthesis with neosinuses, whereas straight tubular graft revealed localized intrados malrotations (P = .003 for organized vortical structures vs neosinuses graft and P < .001 vs control). In the ascending aorta, recreation of the sinuses resulted in significantly lower velocity and WSS than in the straight tubular graft (P < .001) and controls (P < .001), these alterations were attenuated in the mid-descending aorta. Incidence of abnormal WSS was markedly higher in the straight tube grafts than neosinus of Valsalva grafts.

Conclusions

Re-creation of the sinuses of Valsalva during valve-sparing root replacement is associated with more physiologic flow and significantly lower WSS in the aortic root. Lower WSSs in the distal thoracic aorta is a novel finding with potential implications on distal aortic remodeling.  相似文献   
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