Fixation devices, systems and methods for engaging tissue

Abstract

The invention provides devices, systems and methods for tissue approximation and repair at treatment sites. The devices, systems and methods of the invention will find use in a variety of therapeutic procedures, including endovascular, minimally-invasive, and open surgical procedures, and can be used in various anatomical regions, including the abdomen, thorax, cardiovascular system, heart, intestinal tract, stomach, urinary tract, bladder, lung, and other organs, vessels, and tissues. The invention is particularly useful in those procedures requiring minimally-invasive or endovascular access to remote tissue locations, where the instruments utilized must negotiate long, narrow, and tortuous pathways to the treatment site. In addition, many of the devices and systems of the invention are adapted to be reversible and removable from the patient at any point without interference with or trauma to internal tissues.

What is claimed is: 
     
         1 . A fixation device for engaging tissue comprising: a pair of fixation elements each having a first end, a free end opposite the first end, and an engagement surface therebetween for engaging the tissue, the first ends being movably coupled together such that the fixation elements are moveable between a closed position wherein the engagement surfaces face each other to an inverted position wherein the engagement surfaces face away from each other; and an actuation mechanism coupled to the fixation elements adapted to move the fixation elements between the closed position and the inverted position. 
     
     
         2 . A fixation device as in  claim 1 , wherein the fixation elements are further moveable to an open position between the closed position and the inverted position. 
     
     
         3 . A fixation device as in  claim 2 , wherein in the open position the engagement surface of one fixation element forms an angle of more than about 5.degree. and less than about 90.degree. with the engagement surface of the other fixation element. 
     
     
         4 . A fixation device as in  claim 2  wherein in the open position the engagement surface of one fixation element forms an angle of more than about 90.degree. and less than about 180.degree. with the engagement surface of the other fixation element. 
     
     
         5 . A fixation device as in  claim 1  further comprising a pair of gripping elements, each gripping element moveable with respect to one of the fixation elements and being disposed in opposition to one of the engagement surfaces so as to capture tissue therebetween. 
     
     
         6 . A fixation device as in  claim 5 , wherein the gripping elements have frictional features configured to enhance grip on tissue engaged thereby. 
     
     
         7 . A fixation device as in  claim 5  wherein the gripping elements are movable independently of the fixation elements. 
     
     
         8 . A fixation device as in  claim 5  wherein the gripping elements are biased toward the engagement surfaces. 
     
     
         9 . A fixation device as in  claim 5  wherein the gripping elements are movable from an undeployed configuration in which each gripping element is separated from an opposing engagement surface, to a deployed configuration in which the gripping element is adjacent to the opposing engagement surface. 
     
     
         10 . A fixation device as in  claim 9  wherein each fixation element is at least partially concave and each gripping element is at least partially recessed within the fixation element in the deployed configuration. 
     
     
         11 . A fixation device as in  claim 9  wherein the gripping elements are approximately parallel to each other in the undeployed configuration. 
     
     
         12 . A fixation device as in  claim 1  wherein the actuation mechanism comprises a pair of link members coupled to the first and second fixation elements whereby moving the link members moves the first and second fixation elements. 
     
     
         13 . A fixation device as in  claim 12  wherein the actuation mechanism further comprises a coupling member and a stud slidably coupled to the coupling member, the first ends being coupled to one of either the coupling member or the stud, and the link members being coupled to the other of either the coupling member or the stud. 
     
     
         14 . A fixation device as in  claim 13  wherein the link members are connected to one of either the coupling member or the stud by a hinge. 
     
     
         15 . A fixation device as in  claim 13  wherein the link members are connected to the fixation elements by a hinge. 
     
     
         16 . A fixation device as in  claim 1 , further comprising a locking mechanism adapted to lock the fixation elements in a desired position. 
     
     
         17 . A fixation device as in  claim 16  wherein the actuation mechanism comprises a movable stud coupled to the fixation elements, the locking mechanism being configured to frictionally engage the stud to prevent movement thereof. 
     
     
         18 . A fixation device as in  claim 17  wherein the locking mechanism comprises a wedging element for frictionally engaging the stud. 
     
     
         19 . A fixation device as in  claim 18  further comprising a coupling member having a pair of sidewalls, at least one of the sidewalls sloping toward the other sidewall, the stud being slideable between the sidewalls, the wedging element being movably disposed between the stud and at least one sidewall. 
     
     
         20 . A fixation device as in  claim 19  wherein the wedging element comprises a rolling element configured to roll along the at least one sidewall in engagement with the stud.