STENT ASSEMBLY FOR THORACOABDOMINAL BIFURCATED ANEURYSM REPAIR

摘要

FIELD: medicine.;SUBSTANCE: group of inventions relates to medical equipment, specifically to implantable medical devices in a vessel with bifurcation, in particular to a stent assembly, suitable for treatment of thoracoabdominal (covering both thoracoabdominal bifurcated aneurysm (TABA), specifically, an enlarged thoracoabdominal aneurysm, including bifurcation (split) of the aorta or at least one of the iliac arteries, as well as the method of manufacturing said medical device. Multi-lumen stent assembly, intended for installation in a bifurcation vessel, comprising the main vessel and at least two branches, comprises (i) a self-expandable main body component able to expand from a radially compressed state in a delivery configuration to a radially expanded state, the main body component having a proximal end configured to extend away from the branches of the bifurcated vessel and a distal end configured to extend toward the branches of the bifurcated vessel, and extending along an axis; and (ii) two lumen extensions, each lumen extension comprising a tip portion able to be inserted into one of the lumens of the double-barrel portion from the distal end of the main body component. Main body component comprises at the proximal end a main body portion comprising a lumen in a cylindrical form with a circular cross-section and a constant diameter. Near the distal end of the main body component there is a concave portion comprising a double lumen portion. Middle lines of the concaved portion are concaved along the longitudinal axis of the main body component and define two opposing ridges within an interior of the concaved portion, each ridge partially contacting the other ridge. Two opposing ridges define two lumens of the double-barrel portion. Each of the two lumens extends along an axis. Axes of the two lumens define a central plane which also comprises the axis of the main body component. Main body component further comprises a transition portion extending between the distal end of the main body portion and a proximal end of the concaved portion, wherein the cross-section of the transition portion evolves from a circular shape towards the proximal end of the transition portion to an elliptical shape towards the distal end of the transition portion, larger diameter of this shape is in the central plane. Main body component is formed of a multilayer braiding with a plurality of filaments and is devoid of any cover layer, preferably formed of an interconnected multilayer braiding, more preferably formed of an interlaced multilayer braiding. Intersection of the wall of the transition portion by a plane comprising the axis of the main body component and normal to the central plane defines an angle with respect to the central plane, wherein when the prosthesis assembly is in a fully deployed state, said angle is in the range of at least 10° and not more than 55°. Method of manufacturing said main body component for a prosthesis assembly for installation in a bifurcation vessel comprising a main vessel and at least two branches, includes the following steps: a) providing a mandrel having at least one main portion comprising a cylindrical form and at least two bars connecting to a distal end of the main portion, the two bars being in a cylindrical form and disposed parallel to each other having smaller diameter than the diameter of the cylindrical portion, a linear space being disposed between the two bars along the longitudinal axis of the mandrel; b) providing metal filaments selected from a group of cobalt alloy, titanium, and titanium alloy; c) making a bundle of the metal filaments at an end of the mandrel and fixing the bundle with a fixing means; d) forming a braided framework around the mandrel with the provided metal filaments, the braided framework having at least one cylindrical portion and at least one flattened portion having an oval cross-section; e) making a bundle of the metal filaments and fixing with a fixing means at the other end of the mandrel; f) putting the mandrel and surrounding braided framework into a plastic tube or sac; g) subjecting the mandrel and surrounding braided framework in the plastic tube or sac to an external, preferably hydraulic, pressure so as to create a concaved shape in the flatten portion along the linear space of the mandrel; h) subjecting the concaved framework to a thermal treatment so as to memorise the concaved shape; i) cutting off both ends of the thermal treated framework.;EFFECT: invention provides a new design of a prosthesis, which is able to exclude thoracoabdominal bifurcation aneurysm (TABA), while maintaining blood flow of the branches and collaterals located around and inside the aneurysm.;15 cl, 68 dwg