162 research outputs found

    Successful Management of a Rare Case of Stent Fracture and Subsequent Migration of the Fractured Stent Segment Into the Ascending Aorta in In-Stent Restenotic Lesions of a Saphenous Vein Graft

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    Stent fracture is a complication following implantation of drug eluting stents and is recognized as one of the risk factors for in-stent restenosis. We present the first case of successfully managing a stent fracture and subsequent migration of the fractured stent into the ascending aorta that occurred during repeat revascularization for in-stent restenosis of an ostium of saphenous vein graft after implantation of a zotarolimus-eluting stent. Although the fractured stent segment had migrated into the ascending aorta with a pulled balloon catheter, it was successfully repositioned in the saphenous vein graft using an inflated balloon catheter. Then, the fractured stent segment was successfully connected to the residual segment of the zotarolimus-eluting stent by covering it with an additional sirolimuseluting stent

    Late Stent Thrombosis After Drug-Eluting Stent Implantation: A Rare Case of Accelerated Neo-Atherosclerosis and Early Manifestation of Neointimal Rupture

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    An 80-year old woman suffered from sudden onset of chest pain and dyspnea, and visited the emergency room. She received stent implantation with a biolimus A9-eluting stent (Nobori® 3.0×24 mm) at a the mid-portion of the left anterior descending artery 5 months prior to admission. The emergency 5-month follow-up angiogram was performed under the impression of late stent thrombosis. The follow-up angiogram showed subtotal occlusion at the mid-portion of the left anterior descending artery, which was the same segment of previous stent implantation 5 months ago. Immediately after thrombus aspiration with the thrombus aspiration catheter, the optical coherence tomography showed layered appearance of neointimal hyperplasia and neointimal rupture within the previously stented segment. Thus, neointimal rupture within accelerated growth of neointimal tissue was observed within a relatively shorter period (i.e., about 5 months) after stent implantation

    Monotherapy versus combination therapy of statin and renin–angiotensin system inhibitor in ST-segment elevation myocardial infarction

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    Background: The beneficial effects of statin and renin–angiotensin system inhibitor (RASI) are well-known. In this retrospective cohort study,  2-year clinical outcomes were compared between monotherapy and combination therapy with statin and RASI in ST-segment elevation myocardial infarction (STEMI) patients after stent implantation. Methods: A total of 17,414 STEMI patients were enrolled and divided into the three groups (group A: 2448 patients, statin alone; group B: 2431 patients, RASI alone; and group C: 12,535 patients, both statin and RASI). The principal clinical endpoint was the occurrence of major adverse cardiac events (MACEs) defined as all-cause death, recurrent myocardial infarction, and any repeat revascularization. Results: After adjustment, the cumulative incidences of MACEs in group A (adjusted hazard ratio [aHR] 1.337; 95% confidence interval [CI] 1.064–1.679; p = 0.013) and in group B (aHR 1.375; 95% CI 1.149–1.646; p = 0.001) were significantly higher than in group C. The cumulative incidence of all-cause death in group A was significantly higher than that in group C (aHR 1.539; 95% CI 1.014–2.336; p = 0.043). The cumulative incidences of any repeat revascularization (aHR 1.317; 95% CI 1.031–1.681; p = 0.028), target lesion vascularization, and target vessel vascularization in group B were significantly higher than in group C. Conclusions: A Statin and RASI combination therapy significantly reduced the cumulative incidence of MACEs compared with a monotherapy of these drugs. Moreover, the combination therapy showed a reduced all-cause death rate compared with statin monotherapy, and a decreased repeat revascularization rate compared with RASI monotherapy

    Enhanced efficiency of crystalline Si solar cells based on kerfless-thin wafers with nanohole arrays

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    Several techniques have been proposed for kerfless wafering of thin Si wafers, which is one of the most essential techniques for reducing Si material loss in conventional wafering methods to lower cell cost. Proton induced exfoliation is one of promising kerfless techniques due to the simplicity of the process of implantation and cleaving. However, for application to high efficiency solar cells, it is necessary to cope with some problems such as implantation damage removal and texturing of (111) oriented wafers. This study analyzes the end-of-range defects at both kerfless and donor wafers and ion cutting sites. Thermal treatment and isotropic etching processes allow nearly complete removal of implantation damages in the cleaved-thin wafers. Combining laser interference lithography and a reactive ion etch process, a facile nanoscale texturing process for the kerfless thin wafers of a (111) crystal orientation has been developed. We demonstrate that the introduction of nanohole array textures with an optimal design and complete damage removal lead to an improved efficiency of 15.2% based on the kerfless wafer of a 48 mu m thickness using the standard architecture of the Al back surface field
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