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AP Mishreki E Lim P Cranefield S Pascoe S Jackson DA Stell 《Annals of the Royal College of Surgeons of England》2013,95(5):349-352
Introduction
The results of surgical resection and palliative chemotherapy use in hilar cholangiocarcinoma (HC) have been well publicised but the proportion of patients able to undergo these treatments and the comparative outcomes in a population of patients with HC are less well known.Methods
Patients with HC were identified by review of all patients undergoing percutaneous cholangiography over a nine-year period (2002–2010) in a tertiary facility. The treatment undertaken and outcomes were recorded.Results
Overall, 68 patients were identified (37 female) with a median age of 70 years. Forty-five (66%) were treated solely by insertion of a metal stent (median survival 4.73 months) and nine (13%) also received palliative chemotherapy (median survival 13.7 months). Persisting jaundice after stent insertion was noted in 18 of 35 patients (51%) tested within one month of death. Fourteen patients (21%) underwent surgical resection (median survival 20.2 months).Conclusions
Patients undergoing surgical resection had significantly longer survival than those receiving only a palliative stent but not compared with those also receiving palliative chemotherapy, with short-term follow-up. Only a third of patients, however, receive active treatment (surgery or chemotherapy) and improvements in long-term biliary palliation are needed. 相似文献76.
Ovandir Bazan Jayme Pinto Ortiz Francisco Ubaldo Vieira Junior Reinaldo Wilson Vieira Nilson Antunes Fabio Bittencourt Dutra Tabacow Eduardo Tavares Costa Orlando Petrucci Junior 《Brazilian Journal Of Cardiovascular Surgery》2013,28(4):462-469
Introduction
In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench.Objective
To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream.Methods
To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. ) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements.Results
It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found.Conclusions
Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves. 相似文献77.
Eizmendi I Almendral J Hadid C Ortiz M 《Journal of cardiovascular electrophysiology》2012,23(3):325-329
We describe the case of a 61-year-old woman who underwent successful catheter cryoablation of a symptomatic Hisian ectopy. Diagnosis was based on features of the HV interval assessed from a bipolar recording during mapping. The location of the arrhythmic focus was identified using simultaneous unipolar and bipolar recordings of the His electrogram. This case report highlights the use of 2 new criteria for the diagnosis and mapping of Hisian ectopy, and the successful use of cryothermia for the ablation of extrasystoles arising from the His bundle. 相似文献
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Influence of Tricuspid Bioprosthetic Mitral Valve Orientation Regarding the Flow Field Inside the Left Ventricle: In Vitro Hydrodynamic Characterization Based on 2D PIV Measurements 下载免费PDF全文
Ovandir Bazan Jayme P. Ortiz Newton K. Fukumasu Antonio L. Pacifico Jurandir I. Yanagihara 《Artificial organs》2016,40(2):175-179
The flow patterns of a prosthetic heart valve in the aortic or mitral position can change according to its type and orientation. This work describes the use of 2D particle image velocimetry (PIV) applied to the in vitro flow fields characterization inside the upper part of a left ventricular model at various heart rates and as a function of two orientations of stented tricuspid mitral bioprostheses. In the ventricular model, each mitral bioprosthesis (27 and 31 mm diameter) was installed in two orientations, rotated by 180°, while the aortic bileaflet mechanical valve (27 mm diameter) remained in a fixed orientation. The results (N = 50) showed changes in the intraventricular flow fields according to the mitral bioprostheses positioning. Also, changes in the aortic upstream velocity profiles were noticed as a function of mitral orientations. 相似文献