Loop structure having improved tissue contact capability

Abstract

A loop structure for supporting operative elements in contact with bodily tissue including an elongate body. The elongate body may include an area with a preset curvature and/or a hinge area.

We claim:  
     
         1 . A probe assembly, comprising: 
 an outer member including a wall defining an interior bore having a distal end and a proximal end;    an elongate body, defining a distal region, a distal end, a proximal end and an exterior, carried within the outer member, the distal region of the elongate body including an operative element and defining at least a first stiffness over a substantial portion thereof and a second stiffness, less than the first stiffness, over a portion thereof proximal to the operative element; and    a control element defining a distal portion associated with the distal end of the elongate body and a proximal portion extending along the exterior of the elongate body within the outer member toward the proximal end of the outer member.    
     
     
         2 . A probe assembly as claimed in    claim 1   , wherein the outer member comprises a tubular sheath.  
     
     
         3 . A probe assembly as claimed in    claim 1   , wherein the control element comprises a pull wire.  
     
     
         4 . A probe assembly as claimed in    claim 1   , wherein the elongate body comprises a catheter body.  
     
     
         5 . A probe assembly as claimed in    claim 1   , wherein the elongate body includes a flexible spline extending from adjacent the distal end toward the proximal end.  
     
     
         6 . A probe assembly as claimed in    claim 6   , wherein the flexible spline comprises a solid core wire.  
     
     
         7 . A probe assembly as claimed in    claim 6   , wherein the flexible spline defines a first cross sectional shape over a substantial portion thereof and a second cross sectional shape over a relatively small portion thereof.  
     
     
         8 . A probe assembly as claimed in    claim 7   , wherein the first cross-sectional shape is substantially circular and the second cross sectional shape is substantially flat.  
     
     
         9 . A probe assembly as claimed in    claim 1   , wherein the operative element comprises an electrode.  
     
     
         10 . A probe assembly as claimed in    claim 1   , wherein the operative element comprises a plurality of operative elements, one of the operative elements defines a proximal-most operative element, and the portion of the distal region defining the second stiffness is proximal to the proximal-most operative element.  
     
     
         11 . A probe assembly, comprising: 
 an outer member including a wall defining an interior bore having a distal end and a proximal end;    an elongate body, defining a distal region, a distal end, a proximal end and an exterior, carried within the outer member, the distal region of the elongate body including an operative element and being configured such that, when deployed from the distal end of the outer member, it will assume a loop configuration having a curved portion and a substantially linear portion; and    a control element defining a distal portion associated with to the distal end of the elongate body and a proximal portion extending along the exterior of the elongate body within the outer member toward the proximal end of the outer member.    
     
     
         12 . A probe assembly as claimed in    claim 11   , wherein the outer member comprises a tubular sheath.  
     
     
         13 . A probe assembly as claimed in    claim 11   , wherein the control element comprises a pull wire.  
     
     
         14 . A probe assembly as claimed in    claim 11   , wherein the elongate body comprises a catheter body.  
     
     
         15 . A probe assembly as claimed in    claim 11   , wherein the operative element comprises an electrode.  
     
     
         16 . A probe assembly as claimed in    claim 11   , wherein the operative element is located along the substantially linear portion of the loop.  
     
     
         17 . A probe assembly as claimed in    claim 11   , wherein the operative element comprises a plurality of operative elements located along the substantially linear portion of the loop.  
     
     
         18 . A probe assembly, comprising: 
 an outer member including a wall defining an interior bore having a distal end and a proximal end;    an elongate body, defining a distal region, a distal end, a proximal end and an exterior, carried within the outer member, the distal region of the elongate body including an operative element, the elongate body having a portion with a preset curvature proximal to the operative element; and    a control element defining a distal portion associated with to the distal end of the elongate body and a proximal portion extending along the exterior of the elongate body within the outer member toward the proximal end of the outer member.    
     
     
         19 . A probe assembly as claimed in    claim 18   , wherein the outer member comprises a tubular sheath.  
     
     
         20 . A probe assembly as claimed in    claim 18   , wherein the outer member defines a first stiffness and the portion of the elongate body with a preset curvature defines a second stiffness, the second stiffness being less than the first stiffness.  
     
     
         21 . A probe assembly as claimed in    claim 18   , wherein the preset curvature is a substantially semicircular shape.  
     
     
         22 . A probe assembly as claimed in    claim 18   , wherein the control element comprises a pull wire.  
     
     
         23 . A probe assembly as claimed in    claim 18   , wherein the elongate body comprises a catheter body.  
     
     
         24 . A probe assembly as claimed in    claim 18   , wherein the operative element comprises an electrode.  
     
     
         25 . A probe assembly, comprising: 
 an outer member including a wall defining an interior bore having a distal end and a proximal end;    an elongate body, defining a distal region, a distal end, a proximal end and an exterior, carried within the outer member, the distal region of the elongate body including a portion with a present curvature and a portion supporting a plurality of operative elements, one of the operative elements defining a proximal-most operative element, the elongate body further including a flexible spline located therein and extending from adjacent the distal end toward the proximal end, the flexible spline defining a first stiffness over a first spline portion coextensive with the plurality of operative elements and a second stiffness over a spline second portion located proximal to the proximal-most operative element, the second stiffness being less than the first stiffness; and    a control element defining a distal portion associated with the distal end of the elongate body and a proximal portion extending along the exterior of the elongate body within the outer member toward the proximal end of the outer member.    
     
     
         26 . A probe assembly as claimed in    claim 25   , wherein the outer member comprises a tubular sheath.  
     
     
         27 . A probe assembly as claimed in    claim 25   , wherein the control element comprises a pull wire.  
     
     
         28 . A probe assembly as claimed in    claim 25   , wherein the elongate body comprises a catheter body.  
     
     
         29 . A probe assembly as claimed in    claim 25   , wherein the operative elements comprise electrodes.  
     
     
         30 . A probe assembly, comprising: 
 an outer member including a wall defining an interior bore having a distal end and a proximal end;    an elongate apparatus, defining a distal region, a distal end, a proximal end and an exterior, carried within the outer member, the distal region of the elongate apparatus including an operative element, the elongate apparatus having a portion with a preset curvature proximal to the operative element; and    a control element defining a distal portion associated with to the distal end of the elongate apparatus and a proximal portion extending along the exterior of the elongate apparatus within the outer member toward the proximal end of the outer member.    
     
     
         31 . A probe assembly as claimed in    claim 30   , wherein the elongate apparatus comprises a tubular member defining an interior bore and an elongate body carried within the tubular member and supporting the operative element, and the control element is associated with the distal end of the elongate body.  
     
     
         32 . A probe assembly as claimed in    claim 31   , wherein the tubular member includes the portion with the preset curvature.  
     
     
         33 . A probe assembly as claimed in    claim 30   , wherein the elongate apparatus comprises a catheter body having the portion with a preset curvature.  
     
     
         34 . A probe assembly as claimed in    claim 30   , wherein the outer member comprises a tubular sheath.  
     
     
         35 . A probe assembly as claimed in    claim 30   , wherein the outer member defines a first stiffness and the portion of the elongate apparatus with a preset curvature defines a second stiffness, the second stiffness being less than the first stiffness.  
     
     
         36 . A method of positioning a operative element adjacent tissue, comprising the steps of: 
 providing an outer member including a wall defining an interior bore and having a distal and proximal end;    providing an elongate apparatus defining a distal region that supports the operative element and a region with a preset curvature proximal to the operative element;    providing a control element associated with the distal region of the elongate apparatus;    advancing the outer member into a chamber within the body;    advancing the elongate apparatus through the interior bore of the outer member and into the chamber such that the distal region of the elongate apparatus extends beyond the distal end of the outer member and assumes the preset curvature.    
     
     
         37 . A method as claimed in    claim 36   , further comprising the step of: 
 applying tension to the control element.