Gripper pusher mechanism for tissue apposition systems

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 method for fixing tissue, said method comprising:
 providing an implantable tissue fixation device 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 fixation device 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;   positioning the fixation element relative to tissue so that the tissue is disposed between the pair of gripping elements and the engagement surfaces of the pair of fixation element;   actuating a gripper actuation element to engage and displace one or more of the gripping elements; and   advancing the pair of gripping elements toward the engagement surfaces of the fixation elements.   
     
     
         2 . The method of  claim 1 , further comprising:
 providing a gripper pusher releasably coupled to the implantable fixation device adjacent the pair of gripping elements; and   wherein advancing the pair of gripping elements toward the engagement surfaces of the fixation elements comprises engaging the pair of gripping elements with the gripper pusher.   
     
     
         3 . The method of  claim 2 , wherein engaging the pair of gripping elements with the gripper pusher comprises placing the gripper pusher into an expanded configuration from a collapsed configuration. 
     
     
         4 . The method of  claim 3 , wherein the gripper pusher comprises a spring element having a longitudinal axis, and wherein engaging the pair of gripping elements with the gripper pusher comprises applying a compressive force to the spring element in a direction substantially parallel to the longitudinal axis to move the gripper pusher to the expanded configuration. 
     
     
         5 . The method of  claim 3 , further comprising placing the gripper pusher into the collapsed configuration from the expanded configuration to reduce the radial profile of the gripper pusher relative to the gripper pusher radial profile in the expanded configuration to allow the pair of gripping elements to move away from the engagement surfaces of the fixation elements. 
     
     
         6 . The method of  claim 1 , further comprising moving the first ends of the pair of the fixation elements between a closed position wherein the engagement surface face each other to an inverted position wherein the engagement surfaces face away from each other. 
     
     
         7 . The method of  claim 5 , further comprising moving fixation elements to an open position between the closed position and the inverted position. 
     
     
         8 . A method of fixing tissue, said method comprising:
 providing an implantable tissue fixation device, the fixation device comprising a pair of fixation elements, the pair of fixation elements comprising a first fixation element and a second fixation element, each fixation element having a first end, a free end opposite the first end, and an engagement surface therebetween for engaging the tissue, the fixation device further comprising a pair of gripping elements, the pair of gripping elements comprising a first gripping element and a second gripping element, the first gripping element being disposed in opposition to the engagement surface of the first fixation element and the second gripping element being disposed in opposition to the engagement surface of the second fixation element;   positioning the fixation element relative to tissue so that the tissue is disposed between the first gripping element and the engagement surface of the first fixation element;   capturing the tissue between the first gripping element and the engagement surface of the first fixation element by moving the first gripping element with respect to the first fixation element, and   maintaining the position of the second gripping element with respect to the second fixation element while the first gripping element is moved with respect to the first fixation element.   
     
     
         9 . The method of  claim 8 , further comprising providing a first gripping element actuator coupled to the first gripping element and providing a second gripping element actuator coupled to the second gripping element, wherein
 capturing the tissue between the first gripping element and the engagement surface of the first fixation element comprises moving the first gripping element actuator to move the first gripping element; and   maintaining the position of the second gripping element with respect to the second fixation element comprises holding the second gripping element actuator stationary relative to the second gripping element.   
     
     
         10 . The method of  claim 8 , further comprising releasing the captured tissue between the first gripping element and the engagement surface of the first fixation element by moving the first gripping element away from the first fixation element. 
     
     
         11 . The method of  claim 10 , further comprising repositioning the fixation element relative to the tissue. 
     
     
         12 . The method of  claim 8 , further comprising positioning the fixation element relative to tissue so that the tissue is disposed between the second gripping element and the engagement surface of the second fixation element; and
 capturing the tissue between the second gripping element and the engagement surface of the second fixation element by moving the second gripping element with respect to the second fixation element.   
     
     
         13 . The method of  claim 12 , further comprising releasing the captured tissue between the first gripping element and the engagement surface of the first fixation element by moving the first gripping element away from the first fixation element; and
 releasing the captured tissue between the second gripping element and the engagement surface of the second fixation element by moving the second gripping element away from the second fixation element.   
     
     
         14 . The method of  claim 13 , further comprising repositioning the fixation element relative to the tissue.