Endovascular prosthesis and delivery device

Abstract

In one of its aspects, the present invention relates to an endovascular prosthesis. The endovascular prosthesis includes a first expandable portion expandable from a first, unexpanded state to a second, expanded state to urge the first expandable portion against a vascular lumen and a retractable leaf portion attached to the first expandable portion. The retractable leaf portion comprises at least one spine portion and a plurality of rib portions attached to the spine portion. Longitudinally adjacent pairs of rib portions are free of interconnecting struts. The endovascular prosthesis that can be unsheathed and re-sheathed for repositioning of the endovascular prosthesis prior to final deployment thereof. There is also described a delivery device that that is particularly well suited to delivering the present endovascular prosthesis through tortuous vasculature in the body.

What is claimed is: 
     
         1 . A self-expanding endovascular prosthesis comprising:
 a first expandable portion expandable from a first, unexpended state to a second, expanded state to urge the first expandable portion against a vascular lumen; and   a retractable leaf portion attached to the first expandable portion, the retractable leaf portion comprising a single spine portion connected to the first expandable portion and a plurality of rib portions attached to the spine portion, the single spine portion comprising a pair of rows of rib portions, each row of rib portions connected to one side of the single spine portion, longitudinally adjacent pairs of rib portions being free of interconnecting struts;   wherein, in an expanded configuration of the self-expanding prosthesis, the single spine portion comprises a first radius of curvature over the length of the single spine about an axis transverse to a longitudinal axis of the endovascular prosthesis.   
     
     
         2 . The endovascular prosthesis defined in  claim 1 , wherein, in two dimensions, each rib portion comprises a rib proximal portion, a rib distal portion and a rib intermediate portion disposed therebetween. 
     
     
         3 . The endovascular prosthesis defined in  claim 1 , wherein the rib distal portion of each rib portion configured to be directed toward the first expandable portion. 
     
     
         4 . The endovascular prosthesis defined in  claim 1 , wherein, in two dimensions, each row of rib portions is a substantial mirror image of an adjacent row of rib portions along the single spine portion. 
     
     
         5 . The endovascular prosthesis defined in  claim 2 , wherein, in two dimensions, each rib portion has a variable circumferential width. 
     
     
         6 . The endo vascular prosthesis defined in  claim 1 , wherein a first row of rib portions is connected at a plurality of first connection points to the single spine portion and a second row of rib portions is connected at a plurality of second connection points to the single spine portion, the plurality of first connection points and the plurality of second connection points being longitudinally staggered with respect to one another. 
     
     
         7 . The endovascular prosthesis defined in  claim 1 , wherein, in two dimensions, each rib portion is configured substantially to form an acute angle with respect to a spine longitudinal axis of the single spine portion. 
     
     
         8 . The endovascular prosthesis defined in  claim 1 , wherein, in two dimensions, each rib portion is curved. 
     
     
         9 . The endovascular prosthesis defined in  claim 1 , wherein, in two dimensions, each rib portion comprises at least two sub-portions each sub-portion form a different angle with respect to a longitudinal axis of the endovascular prosthesis. 
     
     
         10 . The endovascular prosthesis defined in  claim 1 , wherein the first radius of curvature is variable from a proximal portion of the single spine portion to a distal portion of the single spine portion. 
     
     
         11 . The endovascular prosthesis defined in  claim 1 , wherein the first radius of curvature decreases from a proximal portion of the single spine portion to a distal portion of the single spine portion. 
     
     
         12 . The endovascular prosthesis defined in  claim 1 , wherein, in an expanded configuration of the endovascular prosthesis, the retractable leaf portion comprises an arc of curvature about a longitudinal axis of the endovascular prosthesis in the range of from about 175° to about 225°. 
     
     
         13 . The endovascular prosthesis defined in  claim 1 , wherein, in an expanded configuration of the endovascular prosthesis, the retractable leaf portion comprises an arc of curvature about a longitudinal axis of the endovascular prosthesis of about 200°. 
     
     
         14 . The endovascular prosthesis defined in  claim 2 , wherein in two dimensions, the ratio of the perpendicular distance from the longitudinal axis to the distal tip portion of the rib portion to 50% of the circumference of the first expandable portion in the second, expanded state is in the range of from about 1:4 to about 1:1. 
     
     
         15 . The endovascular prosthesis defined in  claim 1 , wherein the retractable leaf portion comprises a second radius of curvature over the length of the at least one spine portion about a longitudinal axis of the endovascular prosthesis. 
     
     
         16 . The endovascular prosthesis defined in  claim 15 , wherein the second radius of curvature is substantially constant from a proximal portion of the retractable portion to a distal portion of the retractable portion. 
     
     
         17 . The endovascular prosthesis defined in  claim 1 , wherein a pair of longitudinally adjacent rib portions are spaced at a connection point to the spine portion at a distance ranging from about 0.1400 mm to about 0.6 mm. 
     
     
         18 . An aneurysm treatment system comprising the endovascular prosthesis defined in  claim 1  detachably coupled to an endovascular prosthesis delivery device. 
     
     
         19 . An endovascular prosthesis comprising:
 a first expandable portion expandable from a first, unexpended state to a second, expanded state to urge the first expandable portion against a vascular lumen; and   a retractable leaf portion attached to the first expandable portion, the retractable leaf portion comprising a single spine portion connected to the first expandable portion and a plurality of rib portions attached to the spine portion, the single spine portion comprising a pair of rows of rib portions, each row of rib portions connected to one side of the single spine portion, longitudinally adjacent pairs of rib portions being free of interconnecting struts;   wherein a pair of longitudinally adjacent rib portions are spaced at a connection point to the spine portion at a distance ranging from about 0.14 mm to about 0.254 mm.   
     
     
         20 . An endovascular prosthesis comprising:
 a first expandable portion expandable from a first, unexpended state to a second, expanded state to urge the first expandable portion against a vascular lumen; and   a retractable leaf portion attached to the first expandable portion, the retractable leaf portion comprising a single spine portion connected to the first expandable portion and a plurality of rib portions attached to the spine portion, the single spine portion comprising a pair of rows of rib portions, each row of rib portions connected to one side of the single spine portion, longitudinally adjacent pairs of rib portions being free of interconnecting struts;   wherein, in an expanded configuration of the endovascular prosthesis, the retractable leaf portion comprises an arc of curvature about a longitudinal axis of the endovascular prosthesis in the range of from about 200° to about 360°.