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81.
Mataichi Ohkubo Ken Takahashi Masahiko Kishiro Katsumi Akimoto Yuichiro Yamashiro 《Pediatrics international》2004,46(1):39-47
Abstract Background : Use of balloon angioplasty or stent implantation has been reported to be effective in relieving coarctation of the aorta. However, restenosis frequently occurs after balloon angioplasty for native aortic coarctation in small infants, and sometimes develops after stent implantation because of vessel growth. The causes of restenosis remain uncertain. The purpose of this study was to assess the histologic differences in vascular responses to angioplasty using conventional balloon, radiofrequency thermal balloon (RFTB), or stent for experimental aortic coarctation. Methods : The authors surgically created an aortic coarctation model using 14 puppies. Angioplasty using conventional balloon, RFTB, or stent was performed 1 month after the initial operation. At the acute or chronic phase after angioplasty, the animals were killed and histologic studies were performed. Results : More vascular injuries were noted in the specimens from animals undergoing conventional angioplasty than in those with RFTB or stent. However, neointimal hyperplasia was seen more often after RFTB or stent because of the proliferation of smooth muscle cells from the tunica media, caused by secretion of growth factors. Apoptosis reached a peak 1?2 weeks after angioplasty, regardless of the type of intervention. Conclusions : The authors conclude that angioplasty with RFTB or stent can provide relatively small injuries in the vessel wall for aortic coarctation, but care must be taken to prevent restenosis caused by intimal hyperplasia, because neointima hyperplasia is more frequent after RFTB or stent. 相似文献
82.
大豆黄酮血管舒张作用与血管内皮的关系 总被引:6,自引:2,他引:6
目的研究植物雌激素大豆黄酮(daidzein,Dai)的舒张血管效应与血管内皮M受体,细胞内、外钙的关系。方法采用家兔离体主动脉环进行等长张力实验。结果Dai(3~100μmol·L-1)对苯肾上腺素(phenylephrine,PHE)依内Ca2+性收缩和依外Ca2+性收缩均具有显著的抑制作用;Dai(10~100μmol·L-1)可使KCl的量效曲线右移,最大效应降低;Dai(10~100μmol·L-1)对ACh引起的血管环的舒张反应有浓度依赖性的增强作用,且在用阿托品阻断M受体后Dai对KCl引起的收缩的舒张效应减弱。结论Dai舒张血管效应与抑制内Ca2+释放和外Ca2+内流有关;Dai对血管环的直接舒张作用与ACh相似,也是通过激动内皮上的M受体释放EDRF等而引起的,且具有内皮依赖性。 相似文献
83.
In analogy with the good results of laparoscopic abdominal procedures minimal-access aortic surgery looks very promising. However, in spite of the many technical improvements that have already been made, totally laparo-scopic and even laparoscopically assisted aortic surgery remains technically demanding. This explains the rather slow introduction of minimal-access aortic surgery in the vascular society. In anticipation of increasing surgical experience and better instrumentation that will make the technique feasible for each vascular surgeon, hand-assisted laparoscopy (HALS) can be a valuable intermediate approach. HALS offers an easy to perform and still clearly less invasive approach for all aorto-iliac reconstructions. 相似文献
84.
Our discovery of a case of persistent double dorsal aorta prompted us to systematically review the literature of all previously reported cases of this anomaly. For our case, we present a completely separated double dorsal aorta, with the right accessory aorta arising from the abdominal aorta and ascending through the aortic hiatus to supply posterior intercostal arteries (PIAs) to the 9th‐3rd spaces bilaterally. We examined and compiled data from the 10 previously reported cases, along with our observations from our cadaver, into a systematic review of all known cases of persistent double dorsal aorta. In addition to our case report and systematic review, we investigated the literature focusing on formation of the dorsal aorta in the embryo in order to postulate potential mechanisms for formation of this anomaly. Two variants of persistent double dorsal aorta have been reported in the literature. The first type is characterized by a double‐lumen descending aorta with a central dividing septum, and the second features complete separation of the two dorsal aortae. The completely separated variant shows further heterogeneity in the origins of the PIAs and the iliac arteries, and the majority of the reported cases also demonstrate additional anatomical anomalies. We outline the events in embryonic dorsal aorta formation as well as discuss several potential mechanisms that could underlie persistent double dorsal aorta formation. Clin. Anat. 30:517–524, 2017. © 2017 Wiley Periodicals, Inc. 相似文献
85.
Catarina Patrício Mariana Marques Silva Pedro Eduardo Silva João Oliveira Luís Bagulho 《Revista portuguesa de cardiologia》2018,37(5):447.e1-447.e6
A 49-year-old woman was hospitalized for acute left foot arterial ischemia. Arterial Doppler revealed occlusion of the dorsalis pedis and posterior tibial arteries. A computed tomography angiography performed to assess abdominal pain showed hepatic, splenic, renal and pancreatic infarctions. A splenic artery embolism and a small aortic wall thrombus at the celiac trunk were identified. No radiological signs of aortic atherosclerosis were found. No predisposing conditions for secondary aortic thrombosis or intracardiac embolic sources were detected. It was determined that primary aortic thrombosis, a rare though potentially serious condition, was to blame. Isolated aortic mural thrombosis therapy is not well established, although systemic anticoagulation, thrombolysis, thromboaspiration, endovascular stent grafting and surgical thrombectomy have been attempted with varying success. In our patient, systemic anticoagulation therapy was initiated and resulted in aortic thrombus resolution. Close clinical follow-up is crucial, as the aortic thrombus can recur despite anticoagulation and aggressive control of the atherosclerotic risk factors. 相似文献
86.
87.
Congenital aortocaval fistula between right aortic sinus of Valsalva and superior vena cava: A rare case report
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Mozhdeh Dabirian MD Ali Ghaemian MD Maryam Nabati MD Samad Golshani MD Mojtaba Shokri MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(3):413-416
Thoracic aortocaval fistula is a very rare cause of left to right shunt. Drainage of fistula into the superior vena cava (SVC) is very uncommon. Clinical symptoms depend on the size of the shunt. We report a rare case of an asymptomatic 27‐year‐old woman with congenital aortocaval fistula to the SVC with a small amount of left to right shunt that was considered for serial medical follow‐up. 相似文献
88.
《Minimally invasive therapy & allied technologies》2013,22(6):534-536
SummaryConventional laparoscopy has not yet been widely adopted for procedures involving the retroperitoneal organs, due to the problems of adequate bowel retraction and the poor access afforded by the position of the root of the mesentery. Developments in retroperitoneal laparoscopy facilitated by balloon dissection have afforded a new minimally invasive approach to the retroperito-neum. We have compared retroperitoneoscopic and laparoscopic approaches to the great vessels in a porcine model. 相似文献
89.
Konstantinos C. Theodoropoulos MD MSc Alexandros Papachristidis MD Michael Papitsas MD Jonathan Byrne MBChB PhD FRCP Mark J. Monaghan PhD FRCP FACC FESC 《Echocardiography (Mount Kisco, N.Y.)》2018,35(1):132-134
We present a case of a 68‐year‐old man with calciphylaxis, who was found to have a floating thrombus in the descending aorta on a transesophageal echocardiogram. The use of 3D echocardiography demonstrated nicely the free motion of the thrombus, emerging from an atherosclerotic plaque in the descending aorta. Anticoagulation was started for thromboembolism prevention. 相似文献
90.
Asad Ullah Roomi M.D. Tugba Kemaloglu Oz M.D. Shammah O. Williams M.D. Navin C. Nanda M.D. Kruti J. Mehta M.B.B.S. Aylin Sungur M.D. David C. McGiffin M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(9):1107-1110
Aorta to pulmonary artery fistula is an uncommon and potentially fatal condition. This case is of a 48‐year‐old Caucasian male with congestive heart failure and multiple aortic valve replacement surgeries who presented with an acquired ascending aortic aneurysm to pulmonary artery fistula diagnosed using two‐dimensional transthoracic echocardiography via nonstandard imaging windows. Three‐dimensional transthoracic echocardiography using live/real time three‐dimensional color Doppler was used to assess the size of the opening of the fistula, providing additional value. This patient was surgically managed and is doing well 8 months postoperation. 相似文献