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31.
Summary From 1982 to 1984 nine of 300 patients undergoing transluminal coronary angioplasty died. The nine coronary arteries and one saphenous aorto-coronary by-pass graft affected by angioplasty were studied by light microscopy. The following types of lesions were found, frequently in association: rupture of the plaque, circumscribed or reaching to the intimal layer or extending beyond it, dissections (fissures) between arterial layers, intra-plaque haemorrhage, plaque emboli and thrombosis. In two cases the therapeutic approach was considered to be clinically and pathologically successful; the patients survived 24 h (case 6) and forty days (case 4). Case 6 which presented recent lesions indicative of success showed, in contrast with the other non-successful cases, rupture affecting not only the initimal layer but also deeper structures of the arterial wall. There were also more extensive fissures. Case 4 which presented late alterations indicative of success showed a plaque fracture whose borders were kept apart by fibrous tissue. In conclusion, we believe that angioplasty allows the re-establishment of arterial blood flow by provoking deep intimal and medial rupture producing a small fissure between the arterial layers and a widening of the lumen; in cases with good late results these alterations cicatrize leaving a wider arterial lumen.  相似文献   
32.
可脱性球囊栓塞治疗颈内动脉海绵窦瘘   总被引:5,自引:0,他引:5  
目的 总结经动脉途径可脱性球囊性栓塞治疗20便颈内动脉海绵窦瘘的经验。方法 采用Magic-BD球囊导管和带标记乳胶球囊,在X线电视屏幕监视下,经股动脉插管。在球囊内注入渗量等渗非离子造影剂闭塞瘘口。结果 20例全部治愈,1次栓塞成功16例。2次栓塞成功4例,颈内动脉通畅率70%,无并发症。结论本方法可作为颈内动脉海绵窦瘘的首选治疗方法,尽可能保留颈内动脉通畅,如侧枝循环好,亦可闭塞患侧颈内动脉。  相似文献   
33.
Flexible tantalum stents: Effects in the stenotic canine urethra   总被引:2,自引:0,他引:2  
Purpose Evaluate the effects of flexible tantalum stents (Strecker) implanted into stenotic canine urethras.Methods Eight conditioned, adult, German shepherd dogs, weighing 30–40 kg, were used. Strictures were created surgically in the bulbar urethra just proximal to the os penis. Two months postsurgery, strictures were documented radiographically and then balloon dilated. Following dilatation, a single Strecker stent was placed across the stricture. Stents were 7 mm in expanded diameter and either 2 or 4 cm in length. Retrograde urethrography was performed immediately after stent placement and then biweekly for up to 12 months. Two dogs were sacrificed at 2, 4, 6, and 12 months post-stenting, and necropsy was performed. The urethra was excised, fixed, and examined by scanning electron and light microscopy.Results Clinical success was achieved without complications in all animals. Hyperplasia of the urothelium was noted 4–6 weeks after stent placement and was most pronounced at 4–6 months. Mucosal folds were found between the stent struts. Restenosis occurred at the distal end of the stent in one dog. Histological alterations were noted in the deeper layers of the urethral wall.Conclusion Strecker stents were well tolerated in all animals and seem useful for the treatment of urethral strictures.Presented at CIRSE Annual Meeting and Postgraduate Course, Budapest, June 20–24, 1993  相似文献   
34.
Percutaneous balloon dilatation angioplasty is a common therapeutic modality in patients with congenital heart disease. We report three cases of the catheter sheath telescoping into the hub of the sheath after removal of the balloon catheter. Although initially it appeared as though the sheath was torn, in actuality it was intact. We report this problem so others can avoid needless searching and concern for the missing catheter tip.  相似文献   
35.
经皮球囊二尖瓣成形术10年临床经验   总被引:3,自引:1,他引:2  
目的:旨在研究本院400 例经皮球囊二尖瓣成形术10 年的临床经验。 方法:采用改良的Inoue 方法。 结果:经皮球囊二尖瓣成形术即刻成功率98.3% (344/350),术后二尖瓣面积明显增加,达(1.11±0.29)~(2.19±0.40)cm 2。105 例随访9个月~8 年6 个月,二尖瓣再狭窄率为11.4% (12/105),死亡率为2.9% (3/105),二尖瓣置换术为3.8% (4/105)。 结论:经皮球囊二尖瓣成形术近、远期疗效均很好  相似文献   
36.
BACKGROUND: In this observational study we have evaluated the implementation of percutaneous dilation tracheotomy (PDT), using the forceps dilation technique (Portex) in a multidisciplinary ICU. METHODS: We included a preincisional ultrasonic evaluation of the neck in order to visualise the isthmus glandula thyroidea and major vessels. The observational period comprised one year. PDT was performed in 28 patients. RESULTS: Implementation of PDT was uneventful. Duration of insertion was 10 min (4-40 min). Total time of tracheostomy was 8 days (1-65 days). In nine cases, the proximal end of the isthmus was overlying the space between the 1st and 2nd tracheal ring, which was considered the optimal insertion site. This resulted in seven cases of insertion between the cricoidea and the 1st tracheal ring and in two cases in a more distal insertion. Nineteen tracheotomies were performed in the interstice between the 1st and 2nd tracheal ring. In nine patients, major vessels were overlying the trachea. In none of the patients did this information result in an altered insertion site. Two cases of minor bleeding were observed; both stopped upon compression. In two patients the primary tube size (8.0) was too big and a smaller tube had to be inserted. In one patient the tube was maladapted to the stoma and had to be interchanged with an ordinary tracheostomial tube on the 5th day of tracheostomy. CONCLUSION: Based on the experience gathered in this study and information from the literature, we have abandoned the routine use of ultrasonic examination of the neck prior to PDT. In order to achieve and maintain routine, we suggest that the procedure is performed by a restricted number of doctors.  相似文献   
37.
To test iodine-125 labelled low-density lipoprotein (125I-LDL), polyclonal indium-111 labelled immunoglobulin G (111In-IgG) and iodine-125 labelled endothelin-1 uptake in metabolically active atheromatous plaques after arterial wall injury, we performed balloon de-endothelialization of carotid arteries or abdominal aortas in 24 New Zealand male rabbits which were fed with a normal diet (n=14) or a hypercholesterolaemic diet (n=10) after surgery. Six weeks later the animals were injected with 200 Ci of (125I-LDL), and/or with 100 Ci of 111In-IgG or with 9 Ci of 125I-endothelin-1. Forty-eight hours later the animals were sacrificed. Carotid arteries and aortas were removed, counted and fixed for autoradiography and light microscopy examination. Contralateral carotid arteries and thoracic aortas served as controls.Significant 111In-IgG uptake was observed in the injured arteries at autoradiography, with localization mainly in the healing edges, and at well counting. The percentage of the injected dose per gram (%D.inj/g) was 0.0188±0.06 versus 0.0059±0.003 in controls (P< 0.05). There was no difference in 111In-IgG uptake between arteries with injury alone and those with active atheroma formation at the site of the injury. Significant (125I-LDL), uptake was observed only when lipid deposition was present at light microscopy (%D.inj/g of 0.0024±0.0005 vs 0.0010±0.0003 in controls, P < 0.05). 125I-endothelin-1 accumulation was observed in four of five injured aortas both at autoradiography, with diffuse localization, and at well counting (%D.inj/g of 0.0012±0.0004 in the abdominal aortas vs 0.0008±0.0003 in the thoracic aortas).Polyclonal IgG may accumulate in injured arteries without active atheroma formation. Inflammatory reaction at the site of the injury may cause 111In-IgG uptake independently of atheromatous plaque formation. LDL accumulation takes place only with active atheroma formation at the site of the injury. Use of labelled peptides such as endothelin-1 may provide further insight into the mechanisms of atheromatous plaque formation.  相似文献   
38.
Balloon occlusion is the accepted treatment for direct post-traumatic caroticocavernous fistula. We present a case of bilateral traumatic fistulae associated with a pseudoaneurysm. Resolution of both fistulae occurred following treatment of one of them by balloon occlusion of the internal carotid artery. This case highlights the importance of considering a more conservative approach to bilateral fistulae or those associated with a pseudoaneurysm. We review other treatment options. Received: 1 October 1999/Accepted: 20 October 1999  相似文献   
39.
Maternal and perinatal outcome in rheumatic heart disease.   总被引:6,自引:0,他引:6  
OBJECTIVES: To study the maternal and perinatal outcome of pregnancies complicated by rheumatic heart disease. METHODS: A retrospective study was carried out in the cardio-obstetric clinic of the Postgraduate Institute of Medical Education and Research, Chandigarh (India) over a period of 13 years (1987-1999) involving 486 pregnant patients with rheumatic heart disease. Maternal and perinatal outcome was reviewed. RESULTS: Three hundred and four patients (63.3%) had single valve involvement and mitral stenosis was the most predominant lesion (89.2%). One hundred and seventy one (38.6%) patients had undergone surgical correction prior to the onset of pregnancy. One hundred and thirteen patients (22.6%) were identified as NYHA class III-IV. Mitral valvotomy was performed during pregnancy in 48 patients. The incidence of preterm birth and small for gestational age newborns was 12% and 18.2%, respectively. There were 10 maternal deaths, of which eight patients were NYHA III and IV. CONCLUSIONS: Rheumatic heart disease in pregnancy is associated with significant maternal and perinatal morbidity in NYHA class III-IV patients.  相似文献   
40.
气囊扩张对74例良性溃疡伴幽门梗阻的长期疗效再探讨   总被引:1,自引:0,他引:1  
目的 再次评价气囊扩张对良性消化性溃疡伴幽门梗阻的长期疗效。方法 患者先行内科保守治疗 ,保守治疗不成功再行内镜下气囊扩张术。幽门螺杆菌阳性均给予根除治疗 ,抗溃疡病药物治疗至少一个月。结果  74例幽门梗阻中有 4 3例内科保守治疗成功 ,另 31例行气囊扩张术 (最大直径 1 2~ 1 4 mm) ,平均扩张次数为 1 .6 8±0 .83次。在随访 2 1 .0 6± 1 3.1 3个月中 ,梗阻的复发率分别为 4 .6 5 %和 1 6 .1 3% (P>0 .0 5 ) ,两组均未见并发症。结论 幽门梗阻气囊扩张术是一种安全、有效的方法 ,最终用多大直径的球囊扩张以梗阻症状解除为准 ,对良性溃疡伴幽门梗阻 ,即使是瘢痕型梗阻首选球囊扩张 ,如扩张不满意者才考虑手术治疗。  相似文献   
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