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The shape memory properties (SMP) of long‐chain branched poly(lactic acid) (b‐PLA) vascular stent prepared through 3D‐printed technologies are studied by comparison with PLA. SMP is expected to endow vascular stent smart properties of self‐expanding stent, which could self‐expand and support the stenosis after reaching the lesion. The shape recovery rate of the b‐PLA samples at 60°C reaches to 93%, which is much higher than that of the PLA samples with 26%. The two‐cycle deformation‐recovery test of dynamic mechanical analysis (DMA) shows that the shape recovery rate of b‐PLA samples at 60°C reaches 98% in the first and second cycle, suggesting the good SMP. Meanwhile, the 3D‐printed b‐PLA vascular stent could recover to initial shape within 22 s, while the PLA vascular stent could not recover to initial shape after shape deformation at 60°C. Furthermore, Two‐dimensional wide‐angle X‐ray diffraction analysis (2D‐WXRD) diffraction results confirm that both PLA and b‐PLA samples exhibit two bright diffraction spots of (200)/(100) plane, and 2D‐SAXS scattering patterns changed from uniform scattering rings to the spindle‐shaped pattern after shape deformation. After shape recovery at 60°C, the 2D‐WXRD diffraction and two‐dimensional small‐angle X‐ray scattering analysis (2D‐SAXS) scattering patterns of the PLA samples remain no change, while b‐PLA samples recover to initial patterns and exhibit diffuse diffraction rings and uniform scattering rings, respectively, long period (Lac) decrease and lamellae thickness (Lc) maintain constant. The above results verify the excellent SMP of b‐PLA vascular stent as well as self‐expandable properties, which mainly ascribing to the combined action of branched entanglement points and lamellae as stationary phase. Besides, cell counting kit‐8 (CCK‐8) assays, cell live/dead staining and cell nuclei/cytoskeleton staining prove the good cell compatibility of b‐PLA stent before and after SMP. [ABSTRACT FROM AUTHOR]

The JR guide catheter is preferred for operability; however, we should pay more attention to the guide catheter in the case of radial artery approach with severe vessel tortuosity especially in patients with hypertension or in older female patients. [ABSTRACT FROM AUTHOR]

Limited data exist regarding fully-covered, self-expandable metal stents (CSEMS) with anchoring fins for the management of malignant distal biliary strictures. The aim of this study is to evaluate their safety and patency. Over a period of 2 years, 70 patients (45 males, 66 ± 13 years) underwent endoscopic retrograde cholangiopancreatography (ERCP) with placement of a 10-mm (67 patients) or 8-mm diameter (3 patients) CSEMS for the palliation of distal malignant biliary obstruction (pancreatic [53] or other [17]). Data were collected prospectively for survival and stent patency; complications were evaluated retrospectively. After CSEMS placement, 17 patients proceeded to surgery, and 53 patients were deemed unresectable. Mean survival for non-surgical candidates was 180 days (range: 15-1091), and 170 days (range: 9-589) for patients who underwent surgical management. CSEMS were left in place and remained patent for a mean of 163 days (range: 15-1091) in non-surgical candidates, and a mean of 55 days (range: 5-126) in surgical candidates. Complications during placement included wire perforations (4) and proximal deployment requiring repositioning (4), one of which was complicated by a bile leak. Post-procedure complications were observed in 24 cases (34%) and included post-ERCP pancreatitis (8, with 2 of them severe), post-procedure pain (5, with 3 requiring admission), cholecystitis (3), stent occlusion (3), cholangitis (2), proximal migration (1), post-sphincterotomy bleeding (1), and sepsis leading to death (1). CSEMS appear to provide acceptable short-term patency rates; however, their limited long-term patency and high complication rate might limit their widespread use. Further long-term prospective data are required to confirm this observation. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate whether drug coating of the recently developed covered SENDAI stents—self‐expandable stents covered with segmented polyurethane (SPU) films—reduces neointimal thickening in animal model. FK506, which is one of the most effective immunosuppressants, was used. Bare stents; non‐coated, covered stents; and FK506‐coated, covered stents were placed bilaterally in the external iliac arteries of beagle dogs. After 1‐month observation period, angiography did not show significant stent‐induced stenosis. Histological evaluation revealed a completely endothelialized intravascular lumen and the absence of thrombus formation. The area of the intimal thickening induced by the FK506‐coated stents was significantly smaller than that induced by the non‐coated stents, whereas it was larger in the case of both the covered stents than that in the case of the bare stent. In conclusion, FK506 treatment of the self‐expandable, covered stents was confirmed to effectively inhibit intimal thickening, although the SPU film used for covering functioned as a drug carrier in addition to a scaffold for intimal formation. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2009 [ABSTRACT FROM AUTHOR]

We newly developed self‐expandable covered stents by combining two of our original technologies. Of these, the first is the dip‐coating covering method that was developed previously for balloon‐expandable stents; the other is the newly developed self‐expandable Nitinol stents, namely, Sendai stents. The three types of covered stents with the expansion diameter of 4.5, 5.0, or 6.0 mm thus obtained had a laser‐processed microporous elastomeric cover film (pore diameter: 100 μm, interpore distance: 250 μm). Although the film was extremely thin (∼15 μm), the film could be expanded without causing any damage, the strut was completely embedded within the film, and the luminal surface of the film was smooth and flat. Mechanical properties such as ideal flexibility to follow the shapes of arteries were almost retained even after covering. As appropriate drugs, the blood‐contacting inner and tissue‐contacting outer surfaces of the film were differentially coated with argatroban for antithrombogenicity or FK506 for anti‐inflammation, respectively. The preliminary in vivo study indicated that the covered stents mounted in the delivery catheter were navigated and placed to appropriate position in the arteries, and permissible neointimal thickening after 1‐month implantation was observed similarly in noncovered stents. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [ABSTRACT FROM AUTHOR]

Background: Aortic valve predilation with balloon aortic valvuloplasty (BAV) is recommended before transcatheter aortic valve implantation (TAVI), despite limited data around the requirement of this preprocedural step and the potential risks of embolization. This study aimed to investigate the trends in practice and associations of BAV on short-term outcomes in the UK TAVI registry., Methods and Results: Eleven clinical endpoints were investigated, including 30-day mortality, myocardial infarction, aortic regurgitation, valve dysfunction, and composite early safety. All endpoints were defined as per the VARC-2 definitions. Odd ratios of each endpoint were estimated using logistic regression, with data analyzed in balloon- and self-expandable valve subgroups. Propensity scores were calculated using patient demographics and procedural variables, which were included in the models of each endpoint to adjust for measured confounding. Between 2007 and 2014, 5887 patients met the study inclusion criteria, 1421 (24.1%) of whom had no BAV before TAVI valve deployment. We observed heterogeneity in the use of BAV nationally, both temporally and by center experience; rates of BAV in pre-TAVI workup varied between 30% and 97% across TAVI centers. All endpoints were similar between treatment groups in SAPIEN (Edwards Lifesciences Inc., Irvine, CA) valve patients. After correction for multiple testing, none of the endpoints in CoreValve (Medtronic, Minneapolis, MN) patients were significantly different between patients with or without predilation., Conclusions: Performing TAVI without predilation was not associated with adverse short-term outcomes post procedure, especially when using a balloon-expandable prosthesis. Randomized trials including different valve types are required to provide conclusive evidence regarding the utility of predilation before-TAVI., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)