Methods and electrode apparatus to achieve a closure of a layered tissue defect

Abstract

Methods for treating anatomic tissue defects such as a patent foramen ovale generally involve positioning a distal end of a catheter device at the site of the defect, exposing a housing and energy transmission member from the distal end of the catheter, engaging the housing with tissues at the site of the defect, applying suction or other approximating tool to the tissue via the housing to bring the tissue together, and applying energy to the tissue with the energy transmission member or to deliver a clip or fixation device to substantially close the defect. Apparatus generally include a catheter body, a housing extending from a distal end of the catheter body for engaging tissue at the site of the defect, and further adapted to house a fusing or fixation device such as an energy transmission member adjacent a distal end of the housing, or a clip or fixation delivery element.

1 . An apparatus for fusing a layered tissue structure, the apparatus comprising:
 a catheter body having a proximal end and a distal end;   a housing on a distal portion of the catheter body; and   an energy transmission member associated with the housing, wherein the energy transmission member is configured to distribute energy over a predetermined pattern.   
     
     
         2 . An apparatus as in  claim 1 , wherein the energy transmission member is disposed over an opening in the housing. 
     
     
         3 . An apparatus as in  claim 2 , wherein the energy transmission member is adapted to allow the housing to appose the layered tissue structure. 
     
     
         4 . An apparatus as in  claim 1 , wherein the energy transmission member is collapsible. 
     
     
         5 . An apparatus as in  claim 1 , wherein the energy transmission member has an active surface. 
     
     
         6 . An apparatus as in  claim 5 , wherein the energy transmission member further comprises an inactive surface. 
     
     
         7 . An apparatus as in  claim 5 , further comprising a non-conductive mask region which defines the active surface. 
     
     
         8 . An apparatus as in  claim 1 , wherein the energy transmission member has a variable active surface region. 
     
     
         9 . An apparatus as in  claim 1 , wherein the energy transmission member is an electrode. 
     
     
         10 . An apparatus as in  claim 9 , wherein the electrode is adapted to penetrate tissue. 
     
     
         11 . An apparatus as in  claim 1 , wherein the energy transmission member has a geometry which substantially approximates the layered tissue structure to be treated. 
     
     
         12 . An apparatus as in  claim 11 , wherein the energy transmission member geometry is adapted to treat a patent foramen ovale ranging in size from about 1 mm to about 30 mm. 
     
     
         13 . An apparatus as in  claim 11 , wherein the energy transmission member geometry comprises a band. 
     
     
         14 . An apparatus as in  claim 13 , wherein the band geometry is selected from the group consisting of elliptical, circular, rectangular, triangular and combinations thereof. 
     
     
         15 . An apparatus as in  claim 13 , wherein the band geometry comprises an undulating wave-like pattern. 
     
     
         16 . An apparatus as in  claim 11 , wherein the energy transmission member geometry comprises a mesh. 
     
     
         17 . An apparatus as in  claim 11 , wherein the energy transmission member geometry comprises one or more lobes. 
     
     
         18 . An apparatus as in  claim 11 , wherein the energy transmission member geometry comprises one or more bars. 
     
     
         19 . An apparatus as in  claim 18 , wherein the bars have a length and a width and wherein the bar length is greater than the bar width. 
     
     
         20 . An apparatus as in  claim 18 , wherein the bars have a first region and a second region, and wherein the first and second regions are hingedly connected. 
     
     
         21 . An apparatus as in  claim 18 , wherein the bars have a first region and a second region, and wherein the first and second regions are oppositely charged regions adapted to deliver bipolar energy. 
     
     
         22 . An apparatus as in  claim 21 , wherein the bars interdigitate. 
     
     
         23 . An apparatus as in  claim 21 , wherein the oppositely charged regions alternate. 
     
     
         24 . An apparatus as in  claim 18 , wherein some of the bars are substantially parallel to each other. 
     
     
         25 . An apparatus as in  claim 24 , wherein the bars comprise at least one opening therein. 
     
     
         26 . An apparatus as in  claim 25 , wherein the at least one opening is a slit disposed between the bars. 
     
     
         27 . An apparatus as in  claim 26 , wherein the bars have a width and the slit has a width that is less than the width of the bars. 
     
     
         28 . An apparatus as in  claim 24 , further comprising a guidewire lumen axially disposed in the catheter body and wherein the guidewire lumen has a distal exit port disposed between the bars. 
     
     
         29 . An apparatus as in  claim 28 , further comprising a ramp adjacent to the distal exit port. 
     
     
         30 . An apparatus as in  claim 28 , wherein the guidewire lumen passes through the housing. 
     
     
         31 . An apparatus as in  claim 24 , wherein the bars are adapted so that a vacuum may be applied through the bars. 
     
     
         32 . An apparatus as in  claim 24 , wherein the bars are adapted so that tissue adherence to the bars is minimized. 
     
     
         33 . An apparatus as in  claim 24 , wherein the bars are adapted to create a smooth interface with the layered tissue structure. 
     
     
         34 . An apparatus as in  claim 24 , wherein the bars are adapted to form an edge from which energy is delivered. 
     
     
         35 . An apparatus as in  claim 1 , wherein the energy transmission member is biased toward a proximal portion of the housing, thereby maximizing the physical distance between the AV node of the heart and an active electrode portion of the energy transmission member positioned over the layered tissue structure to be treated. 
     
     
         36 . An apparatus as in  claim 7 , wherein the non-conductive mask is connected with the active region and forms an insulated region between the housing and the energy transmission member. 
     
     
         37 . An apparatus as in  claim 1 , wherein the energy transmission member is plated or coated for enhanced electrical characteristics. 
     
     
         38 . An apparatus as in  claim 1 , wherein the energy transmission member is coated for enhanced radiopacity. 
     
     
         39 . An apparatus as in  claim 1 , wherein a guidewire port is disposed adjacent to the energy transmission member. 
     
     
         40 . An apparatus as in  claim 1 , wherein the energy transmission member is adapted so that a vacuum may be applied through the energy transmission member. 
     
     
         41 . An apparatus as in  claim 1 , wherein the energy transmission member comprises struts which connect the energy transmission member to the housing. 
     
     
         42 . An apparatus as in  claim 1 , wherein an elastic element flexibly connects the energy transmission member with the housing. 
     
     
         43 . An apparatus as in  claim 1 , further comprising a thermocouple adjacent to the energy transmission member. 
     
     
         44 . An apparatus as in  claim 1 , wherein the housing is adapted to allow fluid delivery to the region of the layered tissue structure when the housing is apposed with the layered tissue structure.