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A 70‐year‐old man with a history of coronary artery bypass grafting 15 years back and arteriovenous (AV) fistula creation in the left arm 1 month back presented with acute coronary syndrome (ACS). He had not received dialysis before his referral. We felt the most likely etiology for these complaints was increased cardiac oxygen demand from an increased cardiac output related to the newly formed left AV fistula. Coronary angiography was done to detect any significant stenosis in the native or grafted vessels. This revealed that the left subclavian artery was totally occluded in the ostioproximal segment and the coronary arteries did not have occlusions to explain the ACS setting. CT angiography confirmed the angiographic findings of the totally occluded left subclavian artery followed by a well‐developed and patent left internal mammary artery to left anterior descending artery. This led to the consideration of a steal syndrome from the coronary artery by the subclavian artery distal to the occlusion. A successful percutaneous endovascular intervention on the left subclavian artery occlusion was performed. Subsequently, the patient became asymptomatic and experienced a dramatic increase in left ventricular ejection fraction.  相似文献   
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Health Services and Outcomes Research Methodology - To slow the spread of COVID-19, most countries implemented stay-at-home orders, social distancing, and other nonpharmaceutical mitigation...  相似文献   
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Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of...  相似文献   
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Journal of Thrombosis and Thrombolysis - The extended use of thromboprophylaxis with direct oral anticoagulants (DOACs) for more than 30 days has been evaluated as an alternative...  相似文献   
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Background

Very little is known about long-term valve durability after transcatheter aortic valve replacement (TAVR).

Objectives

This study sought to evaluate the incidence of structural valve degeneration (SVD) 5 to 10 years post-procedure.

Methods

Demographic, procedural, and in-hospital outcome data on patients who underwent TAVR from 2007 to 2011 were obtained from the U.K. TAVI (United Kingdom Transcatheter Aortic Valve Implantation) registry. Patients in whom echocardiographic data were available both at baseline and ≥5 years post-TAVR were included. Hemodynamic SVD was determined according to European task force committee guidelines.

Results

A total of 241 patients (79.3 ± 7.5 years of age; 46% female) with paired post-procedure and late echocardiographic follow-up (median 5.8 years, range 5 to 10 years) were included. A total of 149 patients (64%) were treated with a self-expandable valve and 80 (34.7%) with a balloon-expandable valve. Peak aortic valve gradient at follow-up was lower than post-procedure (17.1 vs. 19.1 mm Hg; p = 0.002). More patients had none/trivial aortic regurgitation (AR) (47.5% vs. 33%), and fewer had mild AR (42.5% vs. 57%) at follow-up (p = 0.02). There was 1 case (0.4%) of severe SVD 5.3 years after implantation (new severe AR). There were 21 cases (8.7%) of moderate SVD (mean 6.1 years post-implantation; range 4.9 to 8.6 years). Twelve of these (57%) were due to new AR and 9 (43%) to restenosis.

Conclusions

Long-term transcatheter aortic valve function is excellent. In the authors’ study, 91% of patients remained free of SVD between 5 and 10 years post-implantation. The incidence of severe SVD was <1%. Moderate SVD occurred in 1 in 12 patients.  相似文献   
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This study deals with a series of operations to isolate the micro-cellulose from the palm tree spathe sheath by using a modified chemical method to take into account the low cost and the completion speed and its characterization using X-ray diffraction technique (XRD), infrared spectroscopy (FTIR) and scanning electron microscope coupled with element analyzer (SEM/EDX). The results showed that the extraction method succeeded in obtaining very pure microscopic fibers with a width of 2–10 μm with a crystallinity index equal to 79.21%, containing the two cellulose features Iβ and II, that, the conversion ratio of the first to the second was estimated at 32, 87%.  相似文献   
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