Monofilaments such as those consisting of polyamide (PA), polydioxanone (PDS), and poly(vinylidene fluoride) (PVDF), have been commonly used in various industries. However, most are non-biodegradable, which is unfavorable for many biomedical applications. Although biodegradable polymers offer significant benefits, they are still limited by their weak mechanical properties, which is an obstacle for use as a biomaterial that requires high strength. To overcome the current limitations of biodegradable monofilaments, a novel solid-state drawing (SSD) process was designed to significantly improve the mechanical properties of both PA and poly(l-lactic acid) (PLLA) monofilaments in this study. Both PA and PLLA monofilaments exhibited more than two-fold increased tensile strength and a highly reduced thickness using SSD. In X-ray diffraction and scanning electron microscopy analyses, it was determined that SSD could not only promote the α-crystal phase, but also smoothen the surface of PLLA monofilaments. To apply SSD-monofilaments with superior properties to cardiovascular stents, a shaped-annealing (SA) process was designed as the follow-up process after SSD. Using this process, three types of vascular stents could be fabricated, composed of SSD-monofilaments: double-helix, single-spring and double-spring shaped stents. The annealing temperature was optimized at 80 °C to minimize the loss of mechanical and physical properties of SSD-monofilaments for secondary processing. All three types of vascular stents were tested according to ISO 25539-2. Consequently, it was confirmed that spring-shaped stents had good recovery rate values and a high compressive modulus. In conclusion, this study showed significantly improved mechanical properties of both tensile and compressive strength simultaneously and extended the potential for biomedical applications of monofilaments.
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http://dx.doi.org/10.1039/c7bm00011a | DOI Listing |
CVIR Endovasc
January 2025
Department of Radiology, Section of Vascular and Interventional Radiology, University of Washington, 1959 Northeast Pacific Street, Seattle, WA, 98195, USA.
Purpose: To evaluate access site adverse events following ClotTriever-mediated large-bore mechanical thrombectomy via small upper extremity deep veins (< 6-mm).
Materials And Methods: Twenty patients, including 24 upper extremity venous access sites, underwent ClotTriever-mediated large-bore thrombectomy of the upper extremity and thoracic central veins for symptomatic deep vein obstruction unresponsive to anticoagulation. Patients without follow-up venous duplex examinations (n = 3) were excluded.
JACC Cardiovasc Interv
December 2024
Harrington Heart and Vascular Institute, University Hospitals, Cleveland, Ohio, USA.
JACC Cardiovasc Interv
December 2024
Department for Angiology, Brandenburg Medical School Theodor Fontane, Campus Clinic Brandenburg, Center for Internal Medicine I, Berlin, Germany; Department of Angiology, Sankt-Gertrauden-Krankenhaus, Berlin, Germany.
Background: Several randomized clinical trials have shown that the composite endpoint of death, stroke, and myocardial infarction (MI) is equivalent between carotid artery stenting and carotid endarterectomy. However, the risk of minor stroke has been consistently higher with carotid artery stenting.
Objectives: The authors sought to evaluate the safety and effectiveness of a novel carotid stent system comprised of a stent, an adjustable integrated embolic filter and a postdilation balloon, in patients at elevated risk for adverse events from carotid endarterectomy.
J Clin Med
January 2025
Department of Vascular Surgery, University Hospital Zurich, 8091 Zurich, Switzerland.
: The parallel stent graft endovascular aortic repair (PGEVAR) technique is an off-the-shelf option used for elective complex abdominal aortic aneurysm repair with acceptable outcome results, as reported so far. The PGEVAR technique, using chimney or periscope parallel grafts, can also be used for patients with ruptured complex abdominal aortic aneurysms. However, only few data about the mid- to long-term outcomes are available.
View Article and Find Full Text PDFJ Clin Med
December 2024
"Joint-Stock Company" Central Clinical Hospital, Almaty 050060, Kazakhstan.
Intracranial atherosclerosis (ICAS) is a major cause of ischemic stroke, disproportionately affecting populations with significant vascular risk factors. Although ICAS imposes a considerable health burden, research on this condition in Central Asia remains scarce, especially among the Kazakh population. This study analyzes demographic characteristics, treatment outcomes, and procedural challenges associated with ICAS in 216 patients treated at a single institution.
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