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991.
Coronary artery stents have been developed to overcome arterial abrupt closure and restenosis following balloon angioplasty. Complications of stent insertion include loss of the device from its delivery system into the peripheral circulation. Certain types of stents are almost radiolucent, making localization of the lost devices difficult. Nonferromagnetic metallic biomedical implants induce alteration of the local magnetic field and this leads to loss of signal from the surrounding tissues. We have used this property to localize a misplaced coronary artery stent in a 53-year-old man who underwent unsuccessful stent insertion. A 0.5 Tesla magnetic resonance scanner was used to acquire gradient-echo and spin-echo images. An in vitro experiment was first carried out on a stent similar to that used in our patient to establish that it was nonferromagnetic and to determine the optimum imaging technique. Gradient-echo images with a relatively long echo time (22 ms) gave the largest area of signal loss around the stent, and this sequence was used for localization of the stent found in the patient's left profunda femoris artery. This was subsequently confirmed by digital radiography. We have demonstrated the convenience and practicality of using magnetic resonance imaging for the localization of a misplaced coronary artery stent in a patient. The technique is safe, noninvasive, and uses no ionizing radiation.  相似文献   
992.
目的 :观察药物支架在冠心病并糖尿病患者介入治疗的临床疗效。方法 :并发糖尿病的冠心病患者70例常规冠状动脉造影 ,进行经皮冠状动脉介入治疗 ,其中 32例置入雷帕霉素药物涂层支架 ,38例置入普通支架 ,术前术后常规使用阿司匹林和噻氯吡啶 ,术后进行随访。结果 :冠状动脉造影显示 2支以上血管病变占70 .5 6 % ,一共置入雷帕霉素药物涂层支架 5 4枚 ,普通支架 6 2枚 ,所有患者均获得成功。平均随访 (10 .2± 3.5 )个月 ,其中药物支架组复发心绞痛 9例 ,5例发生心肌梗死 ;普通组复发心绞痛 2 0例 ,8例发生心肌梗死 ,所有患者均再次进行冠状动脉造影 ,药物支架内发生再狭窄 4例 ,普通支架内发生再狭窄 2 0例 ,均进行了靶病变重建术。结论 :药物涂层支架对冠心病并发糖尿病患者近期和远期疗效确切 ,能减少再狭窄的发生  相似文献   
993.
Vasospasm following balloon angioplasty of gastroepiploic artery bypass grafts can be prevented or reversed with vasodilators. In our patient, stent deployment for ostial stenosis of a free gastroepiploic artery graft was accompanied by severe, diffuse spasm and a change in graft configuration that required both intensive medical therapy and balloon angioplasty for resolution. © 1995 Wiley-Liss, Inc.  相似文献   
994.
冠状动脉支架术后不同抗凝药物的疗效观察   总被引:3,自引:2,他引:3       下载免费PDF全文
目的 :观察经皮腔内冠状动脉成形术 (PTCA) +支架置入术后不同抗凝药物对各种心脏事件发生的影响以及其副作用。方法 :对 884例冠心病患者置入 12 3 2个支架 ,在 6~ 12月的短期随访中 ,观察术后不同抗凝药物和抗血小板药物对 PTCA+支架术后各种心脏事件发生的影响以及其副作用。结果 :在 PTCA +支架术后 ,抗凝药物可使各种心脏事件发生率有显著降低 ,使用阿斯匹林 +噻氯匹定及低分子肝素后未发生严重出血并发症及支架内血栓。结论 :PTCA +支架术后使用不同抗凝药物和抗血小板药物效果没有明显差异  相似文献   
995.
Atherosclerotic renal artery stenosis (ARAS) may lead to deterioration of renal function or hypertension. The clinical outcome after stent angioplasty of ARAS on renal function and blood pressure control in patients with diabetes and nephrosclerosis is the subject of some controversy. We have analyzed the results of our single-center experience with stent angioplasty for severe (>/= 70%) ostial ARAS and present here the results of a subgroup analysis of those patients who had diabetes mellitus and nephrosclerosis. From 1996 to 2001, 241 patients underwent stent angioplasty for the treatment of ARAS at our center. Of these, 99 patients had diabetes mellitus (41%) and 176 patients (73%) had nephrosclerosis defined as intrarenal resistance index (RI) >/= 0.7 diagnosed by duplex ultrasound. All lesions (n = 355) were treated successfully. Mean blood pressure at baseline was comparable and significantly improved immediately after the intervention in all groups (nondiabetics: 102 +/- 12 to 93 +/- 10 mm Hg; diabetics: 102 +/- 14 to 93 +/- 11 mm Hg; RI < 0.7: 105 +/- 13 to 95 +/- 10 mm Hg; RI = 0.7-0.8: 100 +/- 12 to 92 +/- 10 mm Hg; RI > 0.8: 102 +/- 15 to 92 +/- 11 mm Hg; P < 0.0001 each). Baseline serum creatinine was not significantly lower in nondiabetics compared to diabetics (1.46 +/- 0.9 vs. 1.62 +/- 1.2 mg %; P < 0.05) and increased in patients with nephrosclerosis (RI < 0.7: 1.18 +/- 0.6 mg %; RI = 0.7-0.8: 1.57 +/- 1.1 mg %; RI > 0.8: 1.96 +/- 1.6 mg %). Except for patients without nephrosclerosis who had a normal baseline creatinine, serum creatinine decreased significantly in all subgroups during follow-up. Stent angioplasty of ARAS offers favorable acute and long-term clinical results for the preservation of the renal function and for blood pressure control in patients with diabetes mellitus and nephrosclerosis.  相似文献   
996.
不同类型冠状动脉支架在冠心病治疗中的应用   总被引:2,自引:0,他引:2  
对20例冠心病患者的26处冠状动脉病变植入四种不同类型的冠脉内支架。植入Palmatz-Schatz型支架8枚、Gianturco-Rubin型支架8枚、Multi-Link型支架8枚、NIR-stent2枚。支架植入成功率100%,均无残留狭窄。2例术后股动脉穿刺部位血肿。随访1~18个月,有2例再发心绞痛,其中1例经造影证实为再狭窄。认为根据不同病变选用不同类型的支架是保证支架植入成功的重要环节,植入后用耐高压球囊进一步扩张可减少支架植入后的血栓形成。  相似文献   
997.
药物洗脱支架:如何平衡再狭窄减少与支架内血栓   总被引:1,自引:0,他引:1  
药物先脱支架通过抑制平滑肌细胞的增殖减少了支架内再狭窄,但也因此而出现了支架内血栓的不良反应,现综述其临床益处及局限性,并分析其导致支架内血栓的相习因素.  相似文献   
998.
BACKGROUND: The sirolimus-eluting stent (SES) and the paclitaxel-eluting stent (PES) reduce restenosis in small coronary artery lesions. However, it is not clear which of these stents is superior in terms of clinical outcomes. METHODS: The authors retrospectively examined 197 patients with 245 de novo small coronary artery lesions (相似文献   
999.
The aim of the study was to compare acute and long-term angiographic and clinical outcome of balloon angioplasty and elective stenting in de novo lesions in the body of a saphenous vein graft (SVG). A total of 150 patients, with de novo lesions in SVG, were randomly assigned to balloon angioplasty or elective Wiktor I stent implantation. The angiographic restenosis rate at 6-month follow-up was 32.8% in the balloon group and 19.1% in the stent group (P = 0.069). At 1-year follow-up, target vessel revascularization rate was 31.4% vs. 14.5% (P < 0.05), and event-free survival was 60.0% vs. 76.3% (P < 0.05) for the balloon and stent group, respectively. Elective stent implantation in de novo SVG lesions is associated with a significant lower target vessel revascularization rate and a significant higher event-free survival at 1-year follow-up as compared to balloon angioplasty.  相似文献   
1000.
ObjectivesThe aim of this study was to test whether optical coherence tomographic (OCT) guidance would provide additional useful information beyond that obtained by angiography and lead to a shift in reperfusion strategy and improved clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) with early infarct artery patency.BackgroundAngiography is limited in assessing the underlying pathophysiological mechanisms of the culprit lesion.MethodsEROSION III (Optical Coherence Tomography–Guided Reperfusion in ST-Segment Elevation Myocardial Infarction With Early Infarct Artery Patency) is an open-label, prospective, multicenter, randomized, controlled study approved by the ethics committees of participating centers. Patients with STEMI who had angiographic diameter stenosis ≤ 70% and TIMI (Thrombolysis In Myocardial Infarction) flow grade 3 at presentation or after antegrade blood flow restoration were recruited and randomized to either OCT guidance or angiographic guidance. The primary efficacy endpoint was the rate of stent implantation.ResultsAmong 246 randomized patients, 226 (91.9%) constituted the per protocol set (112 with OCT guidance and 114 with angiographic guidance). The median diameter stenosis was 54.0% (IQR: 48.0%-61.0%) in the OCT guidance group and 53.5% (IQR: 43.8%-64.0%) in the angiographic guidance group (P = 0.57) before randomization. Stent implantation was performed in 49 of 112 patients (43.8%) in the OCT group and 67 of 114 patients (58.8%) in the angiographic group (P = 0.024), demonstrating a 15% reduction in stent implantation with OCT guidance. In patients treated with stent implantation, OCT guidance was associated with a favorable result with lower residual angiographic diameter stenosis (8.7% ± 3.7% vs 11.8% ± 4.6% in the angiographic guidance group; P < 0.001). Two patients (1 cardiac death, 1 stable angina) met the primary safety endpoint in the OCT guidance group, as did 3 patients (3 cardiac deaths) in the angiographic guidance group (1.8% vs 2.6%; P = 0.67). Reinfarction was not observed in either group. At 1 year, the rates of predefined cardiocerebrovascular events were comparable between the groups (11.6% after OCT guidance vs 9.6% after angiographic guidance; P = 0.66).ConclusionsIn patients with STEMI with early infarct artery patency, OCT guidance compared with angiographic guidance of reperfusion was associated with less stent implantation during primary percutaneous coronary intervention. These favorable results indicate the value of OCT imaging in optimizing the reperfusion strategy of patients with STEMI. (EROSION III: OCT- vs Angio-Based Reperfusion Strategy for STEMI; NCT03571269)  相似文献   
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