Patent RU-2429801-C2 (RU)
Inventor: NGUYEN JOHN D
IPC: A61F2/92
Filed: 2005-12-15
Granted: 2011-09-27
Abstract: FIELD: medicine. 
     SUBSTANCE: stent comprising sliding and blocking elements contains a tubular member having a longitudinal axis and a circle. The tubular member comprises at least two adjoining circumferential radial elements. Each radial element comprises an elongated bridge and a closed loop. The elongated bridge contains at least one deflected tooth. The closed loop limits a catching slot. The catching slot from one radial element is provided to arrange the closed loop from the adjoining circumferential radial element ensuring thereby direct assembly of at least two adjoining circumferential radial elements. The catching slot from one radial element also has a configuration providing sliding catching of the elongated bridge of the to hook with sliding possibility on the extended crosspiece of the adjoining circumferential radial element and to induce deflection of at least one deflected tooth of the elongated bridge when passing through the slot so that the tubular member reaches circumferential low-return expansion. In the second version of the stent, the tubular member comprises the first radial element having the first serrated surface, and the second circumferential radial element being in sliding catching with said first radial element, and having the second serrated surface. The first serrated surface can slide along an upper part of the second serrated surface to provide a ratchet effect so that said tubular member carries return. In the third version of the stent, the tubular member comprises the first unit and the second unit. The first unit contains in turn at least two staggered sliding and blocking radial element moving aside a circle, and a flexible connection element. Each radial element has a grip, a retention gap with facing blocking teeth and a slot. The second unit has a configuration similar to the configuration of the first unit, and is adjoining circumferential with the first unit. Radial elements from the second unit are found in sliding catching with the slots of the matched radial elements of the first unit. The grips of the radial elements of the second unit are found in sliding catching with the retention gaps of the matched radial elements of the first unit so that a blocking teeth catch the grips to provide unidirectional expansion. In the fourth version of the stent, the tubular member comprises the first and second longitudinal units each of which contains peaks and hollows. Flanges provided with the blocking tooth expand from peaks in each unit. The slots expands through a segment along the hollows on each unit. The flanges from the first unit are found in sliding catching with the slots of the second unit. A system for treating a vessel segment comprises a catheter having means for expansion and any of stents described above. The catheter is used to deliver the stent to the segment, and the means of expansion are used for stent expansion. In the fifth version of the stent, the tubular member comprises the first unit and the second unit. The first unit accommodates a pair of the first radial elements and the first flexible connection element. The first radial elements are stretched in a circle at least partially. The first flexible connection element connects said pair of the first radial elements. Each first radial element comprises the elongated bridge and the closed loop. Each of the closed loops of the first radial elements limits the slot. The second unit is basically identical to the first one so that the slots of the closed loops of the second unit can accept the closed loops of the first unit for direct sliding connection of the closed loops of the second unit with the elongated bridges of the first unit, while the tubular member reaches circumferential low-return expansion. 
     EFFECT: invention is compact and pressure flexible enough for enabled easy delivery to an involved segment, is expansion flexible enough for matching with the involved body cavity; it expands inhomogeneously to the required diameter without length change, keeps the expanded diameter without significant return, and has a sufficient frame for providing a precise through lumen. 
     38 cl, 35 dwg