92 results about "Vascular graft" patented technology

The invention relates to the field of biomedical materials, discloses a hydrogen sulfide / nitric oxide synergistic anti-inflammatory and anti-coagulation repair promoting coating as well as a preparation method and application thereof, and provides a coating with anti-inflammatory, anti-coagulation and tissue repair promoting functions through the synergistic effect of hydrogen sulfide and nitric oxide. The coating comprises a hydrogen sulfide donor which can spontaneously release hydrogen sulfide or a precursor thereof or release hydrogen sulfide under external stimulation; the coating further comprises a component capable of catalyzing the release of nitric oxide from the endogenous nitric oxide donor. The coating is covalently connected with the surface of a base material through a chemical means to form firm interface bonding; and the coating has a multi-cross-linked network structure, so that the coating is endowed with good stability, and long-term functional application of the coating on the surface of a biomedical material is ensured. The method can be widely applied to surface modification of biomedical materials, especially coating functionalization of implanted instruments such as valve clips, intravascular stents, heart valves, occluders, vascular grafts and myocardial patches.

Provided herein is a device for simultaneous intraoperative leak testing and visualisation of a heart valve seat, the device comprising an end cap configured to engage with and to sealingly close an opening of a tubular vascular graft, the end cap comprising a backing portion, a connector portion, a view port, and at least one fluid conduit element, the connector portion comprising a distal end dimensioned for placement inside of the opening, a first fastening element comprising an external thread, a second fastening element comprising an internal thread and configured to be rotated onto the first fastening element, and the external and internal threads are adapted such that the first and second fastening elements are fittingly engaged with the tubular vascular graft scalingly secured therebetween by less than one rotation of the second fastening element around the outer circumference.

The invention relates to a preparation method of a 3D printing high-density cell tubular vascular graft. The preparation method comprises the following steps: sucking a supernatant obtained by centrifuging a cell suspension away and only remaining bottom pure cells; the preparation method comprises the following steps: uniformly stirring and mixing OMA, pig gelatin and an LAP photoinitiator in a Hank's solution to form a hydrogel precursor solution; extruding the pure cells and the hydrogel precursor solution from a three-axis nozzle by using printing equipment, and immersing the pure cells and the hydrogel precursor solution into a calcium chloride solution; lyase is added to degrade the hydrogel precursor solution, the hydrogel precursor solution is completely degraded, and an independent single-layer pipeline structure with only a remaining pure cell layer is obtained. The invention provides a method for manufacturing high-density pure-cell lumen constructs to mimic native blood vessels by using a self-made microfluidic coaxial 3D bioprinting device. And after the support hydrogel on the inner layer and the outer layer is removed, a single-layer tubular structure of high-density MOVAs only limited to pure cells is obtained. The cells in the pure cell vascular constructs exhibit good cell viability and cell function.

The invention provides a blood vessel graft with a double-layer structure, and particularly relates to application of the blood vessel graft to preparation of an artificial blood vessel. The vascular graft comprises a terylene inner layer of a woven structure and a compact polyurethane outer layer. The blood vessel graft is implanted in a to-be-repaired and / or to-be-replaced blood vessel position or a to-be-bypass-transplanted position in a subject, the original blood vessel can be replaced, and after a period of time, a layer of elastic outer membrane with excellent mechanical properties is formed on the outer surface of the compact polyurethane outer layer, so that the blood vessel graft can be used for repairing and / or replacing the blood vessel. The obtained artificial blood vessel has the property similar to that of an autologous blood vessel. The blood vessel graft and the artificial blood vessel prepared from the blood vessel graft can be made into various calibers so as to meet different clinical requirements.

An apparatus is provided for subcutaneous implantation in a patient using a tunneling instrument. The implantation apparatus comprises a vascular graft and a connector adapted to couple a distal end of the tunneling instrument and a proximal end of the graft. The connector comprises a tip, a first end of the tip configured to be received within the proximal end of the graft, a clip for securing the graft to the tip, and a coupler for a rotatable connection of the tip to the tunneling instrument such that the tip is rotatable about its longitudinal axis relative to the coupler to facilitate attachment of the graft to the tunneling instrument. The implantation apparatus may further comprise a removable sheath configured to substantially cover the length of the graft.

To provide a favorable apparatus and the like.SOLUTION: An apparatus for delivering a vascular arteriovenous graft includes a tubular sleeve 44 defining an internal lumen adapted to be slidably disposed over a tunneling instrument 42. Upon advancement of the tunneling instrument to a desired subcutaneous anatomical location, a shaft is removed while the sleeve remains in a tissue. The sleeve has a linear slit 58 extending from a proximal end to a midpoint of the length of the sleeve. The lumen receives a distal end of the graft and at least a portion of a cannulation chamber. An end portion of the sleeve gradually expands along the slit, providing an enlarged diameter to accommodate the cannulation chamber. A longitudinal force applied to the sleeve from the tissue when the sleeve is removed from the tissue, fixes the graft within the sleeve by radial compression of the sleeve, and the graft and the sleeve are pulled through the tunnel to deploy the vascular graft.SELECTED DRAWING: Figure 8

Therapeutic agents such as Prasugrel, a thienopyridine ADP receptor inhibitor, which inhibit ADP mediated signaling through the P2Y12 receptor, done or in combination with an angiotensin II receptor blocker (ARB) such as Losartan that specifically blocks the angiotensin II type 1 (AT1) receptors, have been shown to be effective in reducing thrombosis and stenosis of grafts, including vascular grafts and tissue engineered vascular grafts ("TEVGs") in multiple in vivo, and that the combination of a inhibitor of the purinergic receptors P2Y12 such as Prasugrel, with losartan, an angiotensin II type 1 receptor inhibitor, more than additively reduced the incidence of TEVG stenosis. In a preferred embodiment, a multi-dosing unit for treatment to reduce stenosis delivers a 2-week course of losartan and Prasugrel.

Synthetic hemocompatible vascular grafts manufactured from polyvinyl alcohol-based biomaterials containing crystalline segments of polyvinyl alcohol, which are long-term fully functioning vascular grafts that provide no activity towards immune systems in recognizing surfaces as foreign bodies that would normally lead to fibrosis, platelet activation and subsequent thrombi formation, and thus occlusion of the grafts.

The invention disclosure provides a composite compliant vascular graft for implantation in a host, which graft includes a tubular body having a lumen and a tubular wall surrounding the lumen made of a composite material, which is adapted to permit expansion of the tubular body from a native state to an expanded state and then to return to the native state in response to pressure changes in the lumen, which includes a mechanical component which is adapted to limit the expanded state, and a compliant component which is adapted to bias return of the tubular body to the native state.

The application discloses an anti-bending artificial blood vessel, which comprises an artificial blood vessel inner layer, a synthetic polymer anti-bending ring and an artificial blood vessel outer layer; the artificial blood vessel inner layer is a synthetic polymer tube body; the artificial blood vessel outer layer is a synthetic polymer fiber membrane; the shape of the synthetic polymer anti-bending ring is a non-equidistant spiral structure; the synthetic polymer anti-bending ring is wound on the outer wall of the artificial blood vessel inner layer, is between the artificial blood vessel inner layer and the artificial blood vessel outer layer, and is fixed by being covered by the artificial blood vessel inner layer and the artificial blood vessel outer layer. The application further discloses a preparation method of the artificial blood vessel. The application can make the artificial blood vessel to be bent by 180 degrees in a full ring without flat collapse and kinking, can ensure that the whole artificial blood vessel has good anti-bending performance, can effectively improve the anti-bending performance of the artificial blood vessel, and can effectively improve the compliance of the artificial blood vessel.

The application discloses a medical instrument technical field, and relates to an integrated type artificial blood vessel with a sinus, which comprises a tube part, a sinus-tube joint and a sinus part which are integrally woven and shaped, and the tube part and the sinus part have a same longitudinal axis, the sinus part has a dense structure which is composed of upper and lower layer fabric tissues which are connected with each other, and the connecting points are located at the overlapping positions of the upper and lower layer tissue points, the fabric coverage of the dense structure is 80%-95%, the upper and lower layer fabric tissues are both woven by a plurality of fabric tissues with a yarn density of not less than 80 root / cm, and the upper and lower layer fabric tissues both contain twill tissues. The application provides an integrated type artificial blood vessel with a sinus, which has a good sinus part form, a dense structure and good stability, the sinus part has a dense tissue structure, so that the elastic performance is ensured, the structure support is strong, the long-term radial overexpansion can be prevented, the service life of the artificial blood vessel and the autologous valve is prolonged, and the possibility of postoperative secondary intervention is reduced.

Described herein are bioengineered constructs and methods of producing the same. The constructs and methods disclosed herein can be applied towards, for example, the generation of vascular grafts to treat cardiovascular disease.

System, apparatus, and method for replacing a segment of vasculature, tissue, or organ.

The disclosed concept includes the use of additive and / or subtractive manufacturing of mesoporous structures on two-dimensional sheets that are mechanically tunable, to provide a vascular graft that controls biodegradable graft host interactions, to improve graft patency and functionality long-term. The vascular graft includes the two-dimensional sheets in a rolled or tubular configuration to form a lumen wherein a surface and / or bulk modification is applied to the flat sheet. In addition, a plurality of mesoporous structures (e.g., gaps) are formed in the flat sheet using a subtractive manufacturing technique.

A vascular graft deployment tool can include a handle, an elongate mandrel positioned distal to the handle, a vascular graft at least partially disposed coaxially about the mandrel, a sheath assembly including a distal sheath portion and a proximal sheath portion, wherein the distal and proximal sheath portions are configured to constrain the vascular graft against the mandrel at an insertion diameter, and an actuator movable relative to the handle and engaging the sheath assembly, wherein operation of the actuator causes at least one of the distal and proximal sheath portions to longitudinally separate to free at least a portion of the vascular graft. Further, the vascular graft is expandable from an insertion state to a deployed state, and at least two suture envelopes are positioned between opposite end portions of the vascular graft.

The disclosure relates to compositions and methods for reducing SMAD3 expression in a blood vessel in a patient in need thereof. Also provided herein are compositions and methods for reducing blood vessel graft stenosis in a subject, preventing occlusion of a blood vessel or a blood vessel graft, reducing neointimal hyperplasia in a blood vessel or a blood vessel graft, increasing endothelization in a blood vessel or a blood vessel graft, increasing patency in a blood vessel or a blood vessel graft, reducing endothelial to mesenchymal transition (EndMT) in a blood vessel or a blood vessel graft, reducing thrombosis in in a blood vessel or a blood vessel graft and / or reducing TGF-beta signaling in a blood vessel or a blood vessel graft. In embodiments, the patient is undergoing arterio-venous fistula (AVF) surgery.

The present disclosure relates to an implantable vascular graft material, including: a substrate including a graft material, the substrate defining a top surface and a bottom surface; and one or more bispecific binding partners having a luminal binding domain bound to the top surface and one or more cellular binding domains. In embodiments, the disclosure includes an implantable vascular graft including: a tubular base layer including a graft material, the tubular base layer defining a luminal surface and an abluminal surface; and a fusion peptide having a heparin binding domain bound to the luminal surface and one or more monocyte binding domains. In embodiments, the present disclosure provides one or more implantable vascular grafts such as A-TEVs, methods of making vascular grafts, methods of use, and the like.

Provided herein are methods of generating optimized models of vascular grafts for subjects in certain embodiments. Methods of treating subjects in need of vascular grafts are also provided. Related systems and computer program products are additionally provided.

The development of devices for a functional cure for diabetes by mimicking native pancreatic tissue for production of all pancreatic hormones. A physiologically and mechanically biocompatible artificial pancreas, wherein the pancreas comprises a combination of a PVA hydrogel combined with cells selected from the group consisting of islets; clusters of islets; Beta cells, and combinations of islets and Beta cells. The bioartificial pancreas contains vascular grafts therein or thereon a wall of the pancreas so that said grafts are an integral part of the wall of the bioartificial pancreas. The grafts can be anasmotized to living blood vessels in the body.

The invention provides a small-caliber blood vessel biological scaffold capable of adjusting stress relaxation and a preparation method of the small-caliber blood vessel biological scaffold. The biological scaffold is of a tubular structure which is formed by arranging micron fibers and nanofibers in a crossed mode, is arranged in a net shape and is provided with a layered tube wall. The small-caliber blood vessel biological scaffold has adjustable stress relaxation performance, biodegradability, bionic viscoelasticity and excellent surgical suture performance, endogenous cells can be guided to be clustered and self-assembled, a small-caliber blood vessel graft with the deformation behavior close to that of a natural blood vessel is formed, and the small-caliber blood vessel biological scaffold has the advantages of being simple in structure and convenient to use. And the double bottleneck that the mechanical property and the tissue regeneration function of the traditional stent are difficult to consider is solved.

Current approaches in small diameter vascular grafts for coronary artery bypass surgeries fail to address physiological variations along the graft that contribute to thrombus formation and ultimately graft failure. An interlayer drug delivery system can sustain delivery of heparin through the graft with a high degree of temporal and spatial control. A heparin-loaded gelatin methacrylate interlayer sits between a biohybrid composed of decellularized bovine pericardium and poly(propylene fumarate) and UV crosslinking is controlled via 3D printed shadow masks. The masks enable control of the resultant gelMA crosslinking and properties by modulating the incident light intensity on the graft. High doses of heparin have detrimental effects on endothelial cell function. When exposed to heparin in a slower, more sustained manner consistent with the masks, endothelial cells behave similarly to untreated cells. Slower release profiles cause significantly more release of tissue factor pathway inhibitor, an anticoagulant, than a faster release profile.

The invention relates to a multilayer polymer composite vascular graft and a method for its manufacturing The said vascular graft comprises a first layer containing PCL-Heparin, a second layer containing PCL, a third layer containing PVA-Chitosan and a fourth layer containing TPU. The electrospinning method is used to prepare the vascular graft in question. In the vascular graft subject to the invention, both biodegradable (PCL, chitosan) and non-biodegradable polymer materials (TPU) are used. By supporting the biodegradable materials (PCL, chitosan), which lose their mechanical properties during the endothelialisation process, with the non-biodegradable polymer material (TPU), the problem caused by the potential loss of mechanical strength is eliminated. Thanks to the heparin additive in the inner layer of the vascular graft subject to the invention, clotting, which is commonly encountered in vascular graft applications, is also prevented.

Provided herein our graft devices for a patient comprising one or more layers, such as an inner layer and an outer layer. The inner layer comprises a first porous arrangement of fibers defining a first tube comprising an inner wall and an outer wall. The outer layer comprises a second porous arrangement of fibers defining a second tube comprising an inner wall and an outer wall. The second tube surrounds the first tube. A plurality of macropores extend through at least the inner and outer wall of the first tube. The inner and / or the outer layer can comprise a biofragmentable material configured to mechanically fracture into one or more fragments over time. Methods of creating graft devices are also disclosed.

The invention provides a composite membrane for vascular transplantation and a preparation method of the composite membrane. The composite membrane comprises stacked degradable coatings, the degradable coatings comprise a first degradable coating, a second degradable coating, a third degradable coating and a fourth degradable coating; each layer of degradable coating comprises a drug sustained-release matrix and a drug dispersed in the drug sustained-release matrix; the drug sustained-release matrix is a PVA (Polyvinyl Alcohol) film; the medicines comprise antibiotics and / or antibacterial agents. The composite membrane for vascular transplantation has good drug controlled release ability, has high anti-infection and anti-adhesion ability, is almost suitable for all types of vascular grafts, and breaks through the limitation of a coating technology in application.

The present disclosure describes a system and a method for producing patient-specific small diameter vascular grafts (SDVG) for coronary artery bypass graft (CABG) surgery. In some embodiments, the method for producing SDVGs includes non-invasive quantification of patient-specific coronary and vascular physiology by applying computational fluid dynamics (CFD), rapid prototyping, and in vitro techniques to medical images and coupling the quantified patient-specific coronary and vascular physiology from the CFD to computational fluid-structure interactions and SDVG structural factors to design a patient-specific SDVG.

A hybrid modular endovascular graft wherein a main graft is sized to span at least a portion of a target vessel lesion in a large percentage of patients. Graft extensions may be secured to the main graft to extend the main graft and provide a sealing function for some applications.

An access device for a vascular graft is disclosed. The access device can allow two large-diameter medical devices to be inserted at the same time. The access device may include a body defining a common arm, a first proximal arm, and a second proximal arm. The common arm may include a common lumen extending from a distal end of the common arm to a proximal end of the common arm. The first arm may include a first lumen extending from a proximal end of the first arm to the common lumen. The second arm may include a second lumen extending from a proximal end of the second arm to the common lumen. The access device may include a plurality of hemostasis valves. A first hemostasis valve may be disposed at a proximal end of the first proximal arm. A second hemostasis valve may be disposed at a proximal end of the second proximal arm.

The present invention relates to the field of medical instruments, and in particular to a subcutaneous tunneller assembly for an arteriovenous graft, comprising dilators, a guide wire, and a sleeve. Two dilators are provided and each are of a tubular structure having openings at two ends and each have a bendable segment. The sleeve has a cavity matching a vascular graft. The guide wire is arranged in a communicated internal cavity formed by the abutment of the two dilators. The bendable segments respectively enable the two dilators to bend and deform to match a preset path of a subcutaneous tunnel, and the dilators are respectively placed subcutaneously via a skin incision, and then abut against each other by means of the end portions, such that a continuous curved U-shaped subcutaneous tunnel can be established, thereby reducing skin incisions, minimizing surgical trauma, and preventing concurrent infections. The sleeve can protect the vascular graft from coming into contact with the skin, and lower the risk of intraoperative infection; after placing the vascular graft into the sleeve, there is no need to adjust the position, thereby preventing bending, kinking, or angulation during the placement of the vascular graft.

A vascular graft and method of fabricating the same are provided. The vascular graft includes an elongated tube fabricated from a material having a plurality of nodes interconnected by a plurality of fibrils. The elongated tube extends along an axis and has been previously stretched along the axis from an initial length to a desired length. Each of the plurality of fibrils has a length, and first and second ends separated by a linear distance. After the second stretching, the length of each of a majority of the plurality of fibrils is greater than the linear distance between the first and second ends of each of the majority of the plurality of fibrils, thereby allowing the vascular graft of the present invention to exhibit higher elastic compliance than prior synthetic, vascular grafts.

Provided herein are methods of generating optimized models of vascular grafts for subjects in certain embodiments. Methods of treating subjects in need of vascular grafts are also provided. Related systems and computer program products are additionally provided.