Systems and methods for forming large lesions in body tissue using curvilinear electrode elements

Abstract

Systems and associated methods form larger and deeper lesion patterns by shaping a support body with multiple electrodes in ways that increase the density of the electrodes per given tissue area. The support body can carry either elongated, continuous electrodes or arrays of non-contiguous, segmented electrodes.

We claim:  
     
         1 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two energy emitting zones on the curved region mutually separated across the contacted tissue area, the mutual separation between the zones across the contacted tissue area creating, when the zones simultaneously emit energy, an additive heating effect to form a continuous lesion pattern in the contacted tissue area that spans across the contacted tissue area.    
     
     
         2 . A device according to  claim 1   and further including a continuous energy emitting electrode on the curved region of the support element.    
     
     
         3 . A device according to  claim 2   wherein the continuous electrode includes at least two energy applying zones spaced apart along the curved region and separated across the contacted tissue area.    
     
     
         4 . A device according to  claim 1   wherein the two energy emitting zones comprise non-contiguous energy emitting segments spaced apart on the curved region and mutually separated across the contacted tissue area.    
     
     
         5 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two energy emitting zones on the curved region mutually separated across the contacted tissue area, each zone having a diameter, the radius of curvature of the curved region being equal to or less than about 3.5 times the smaller of the diameters of the first and second zones to create, when the zones simultaneously emit energy, a continuous lesion spanning across the contacted tissue area.    
     
     
         6 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two energy emitting zones on the curved region mutually separated across the contacted tissue area, each zone having a length and a diameter, the length of each zone being greater than about 5 times the diameter of the respective zone, the radius of curvature of the curved region being equal to or less than about 3.5 times the smaller of the diameters of the first and second zones to create, when the zones simultaneously emit energy, a continuous lesion spanning across the contacted tissue area.    
     
     
         7 . A device according to  claim 5  or  6  
 and further including a continuous energy emitting electrode on the curved region of the support element.  
 
     
     
         8 . A device according to  claim 7   wherein the continuous electrode includes at least two energy applying zones spaced apart along the curved region and separated across the contacted tissue area.    
     
     
         9 . A device according to  claim 7   wherein the continuous electrode comprises a material extending about the curved region of the support element through which energy is emitted.    
     
     
         10 . A device according to  claim 7   wherein the continuous electrode comprises a coating of material on the curved region of the support element through which energy is emitted.    
     
     
         11 . A device according to  claim 7   wherein the continuous electrode comprises wire helically wrapped about the curved region of the support element.    
     
     
         12 . A device according to  claim 5  or  6  
 wherein the two energy emitting zones comprise non-contiguous electrode segments spaced apart on the curved region of the support element.  
 
     
     
         13 . A device according to  claim 12   wherein at least one of the electrode segments comprise metallic material attached about the support element.    
     
     
         14 . A device according to  claim 12   wherein at least one of the electrode segments comprises wire helically wrapped about the curved region of the support element.    
     
     
         15 . A device according to  claim 12   wherein at least one of the electrode segments comprise a coating of material on the support element through which energy is emitted.    
     
     
         16 . A device according to  claim 5  or  6  
 wherein the support element is flexible and includes means for flexing the element to form the curved region.  
 
     
     
         17 . A device according to  claim 16   wherein the flexing means flexes the support element from a generally straight configuration to form the curved region.    
     
     
         18 . A device according to  claim 16   wherein flexing means flexes the support element from a generally straight configuration to selectively form the curved region on opposite sides of the generally straight configuration.    
     
     
         19 . A device according to  claim 5  or  6  
 wherein the curved region is formed in the shape of a hoop.  
 
     
     
         20 . A device according to  claim 5  or  6  
 wherein the curved region is formed in the shape of a hook.  
 
     
     
         21 . A device according to  claim 5  or  6  
 wherein the radius of curvature of the curved region is equal to or less than about 2.5 times the smaller of the diameters of the first and second zones.  
 
     
     
         22 . A device according to  claim 21   wherein the radius of curvature of the curved region is equal to or less than about 1.5 times the smaller of the diameters of the first and second zones.    
     
     
         23 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two non-contiguous energy emitting zones on the curved region mutually separated across the contacted tissue area, each zone having a diameter, the separation between the zones across the contacted tissue area being equal to or less than about 7 times the smaller of the diameters of the first and second zones to create, when the zones simultaneously emit energy, a continuous lesion spanning across the contacted tissue area.    
     
     
         24 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two non-contiguous energy emitting zones on the curved region mutually separated across the contacted tissue area, each zone having a length and a diameter, the length of each zone being equal to or less than about 5 times the diameter of the respective zone, the separation between the zones across the contacted tissue area being equal to or less than about 7 times the smaller of the diameters of the first and second zones to create, when the zones simultaneously emit energy, a continuous lesion spanning across the contacted tissue area.    
     
     
         25 . A device according to  claim 23  or  24  
 wherein the separation between the zones across the contacted tissue area is equal to or less than about 5 times the smaller of the diameters of the first and second zones.  
 
     
     
         26 . A device according to  claim 25   wherein the separation between the zones across the contacted tissue area is equal to or less than about 3 times the smaller of the diameters of the first and second zones.    
     
     
         27 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two non-contiguous energy emitting zones on the curved region mutually separated across the contacted tissue area, each zone having a length, the separation between the zones across the contacted tissue area being equal to or less than about 4 times the longer of the lengths of the first and second zones to create, when the zones simultaneously emit energy, a continuous lesion spanning across the contacted tissue area.    
     
     
         28 . A device for ablating body tissue comprising 
 a support element having a curved region to peripherally contact a tissue area, and    at least two non-contiguous energy emitting zones on the curved region mutually separated across the contacted tissue area, each zone having a length and a diameter, the length of each zone being equal to or less than about 5 times the diameter of the respective zone, the separation between the zones across the contacted tissue area being equal to or less than about 4 times the longer of the lengths of the first and second zones to create, when the zones simultaneously emit energy, a continuous lesion spanning across the contacted tissue area.    
     
     
         29 . A device according to  claim 27  or  28  
 wherein the separation between the zones across the contacted tissue area is less than about 3 times the longer of the lengths of the first and second zones.  
 
     
     
         30 . A device according to  claim 23  or  24  or  27  or  28  
 wherein at least one of the two energy emitting zones comprise metallic material attached about the support element.  
 
     
     
         31 . A device according to  claim 23  or  24  or  27  or  28  
 wherein at least one of the two energy emitting zones comprise wire helically wrapped about the support element.  
 
     
     
         32 . A device according to  claim 23  or  24  or  27  or  28  
 wherein at least one of the two energy emitting zones comprise a coating of material on the support element through which energy is emitted.  
 
     
     
         33 . A device according to  claim 23  or  24  or  27  or  28  
 wherein the support element is flexible and includes means for flexing the element to form the curved region.  
 
     
     
         34 . A device according to  claim 33   wherein the flexing means flexes the support element from a generally straight configuration to form the curved region.    
     
     
         35 . A device according to  claim 33   wherein flexing means flexes the support element from a generally straight configuration to selectively form the curved region on opposite sides of the generally straight configuration.    
     
     
         36 . A device according to  claim 22  or  24  or  27  or  28  
 wherein the curved region is formed in the shape of a hoop.  
 
     
     
         37 . A device according to  claim 22  or  24  or  27  or  28  
 wherein the curved region is formed in the shape of a hook.  
 
     
     
         38 . A method for ablating body tissue comprising the steps of 
 positioning at least two energy emitting zones along a curve in peripheral contact with a tissue area in a mutually closely separated relationship across the contacted tissue area, and    conditioning the zones to simultaneously emit energy to create an additive heating effect to form a continuous lesion pattern in the contacted tissue area that spans across the contacted tissue area.    
     
     
         39 . A method for ablating body tissue comprising the steps of 
 positioning at least two energy emitting zones along a curve in peripheral contact with a tissue area, each zone having a diameter, the radius of curvature of the curved region being equal to or less than about 3.5 times the smaller of the diameters of the first and second zones, and    conditioning the zones to simultaneously emit energy to create a continuous lesion spanning across the contacted tissue area.    
     
     
         40 . A method for ablating body tissue comprising the steps of 
 positioning at least two energy emitting zones along a curve in peripheral contact with a tissue area, each zone having a length and a diameter, the length of each zone being greater than about 5 times the diameter of the respective zone, the radius of curvature of the curved region being equal to or less than about 3.5 times the smaller of the diameters of the first and second zones, and    conditioning the zones to simultaneously emit energy to create a continuous lesion spanning across the contacted tissue area.    
     
     
         41 . A method according to  claim 39  or  40  wherein the radius of curvature of the curved region is equal to or less than about 2.5 times the smaller of the diameters of the first and second zones.  
     
     
         42 . A method according to  claim 41   wherein the radius of curvature of the curved region is equal to or less than about 1.5 times the smaller of the diameters of the first and second zones.    
     
     
         43 . A method for ablating body tissue comprising the steps of 
 positioning at least two non-contiguous energy emitting zones along a curve in peripheral contact with a tissue area, the zones being mutually separated across the contacted tissue area, each zone having a diameter, the separation between the zones across the contacted tissue area being equal to or less than about 7 times the smaller of the diameters of the first and second zones, and    conditioning the zones to simultaneously emit energy to create a continuous lesion spanning across the contacted tissue area.    
     
     
         44 . A method for ablating body tissue comprising the steps of 
 positioning at least two non-contiguous energy emitting zones along a curve in peripheral contact with a tissue area, the zones being mutually separated across the contacted tissue area, each zone having a length and a diameter, the length of each zone being equal to or less than about 5 times the diameter of the respective zone, the separation between the zones across the contacted tissue area being equal to or less than about 7 times the smaller of the diameters of the first and second zones, and    conditioning the zones to simultaneously emit energy to create a continuous lesion spanning across the contacted tissue area.    
     
     
         45 . A method according to  claim 43  or  44  
 wherein the separation between the zones across the contacted tissue area is equal to or less than about 5 times the smaller of the diameters of the first and second zones.  
 
     
     
         46 . A method according to  claim 45   wherein the separation between the zones across the contacted tissue area is equal to or less than about 3 times the smaller of the diameters of the first and second zones.    
     
     
         47 . A method for ablating body tissue comprising the steps of 
 positioning at least two non-contiguous energy emitting zones along a curve in peripheral contact with a tissue area, the zones being mutually separated across the contacted tissue area, each zone having a length, the separation between the zones across the contacted tissue area being equal to or less than about 4 times the longer of the lengths of the first and second zones, and    conditioning the zones to simultaneously emit energy to create a continuous lesion spanning across the contacted tissue area.    
     
     
         48 . A method for ablating body tissue comprising the steps of 
 positioning at least two non-contiguous energy emitting zones along a curve in peripheral contact with a tissue area, the zones being mutually separated across the contacted tissue area, each zone having a length and a diameter, the length of each zone being equal to or less than about 5 times the diameter of the respective zone, the separation between the zones across the contacted tissue area being equal to or less than about 4 times the longer of the lengths of the first and second zones, and    conditioning the zones to simultaneously emit energy to create a continuous lesion spanning across the contacted tissue area.    
     
     
         49 . A method according to  claim 47  or  48  
 wherein the separation between the zones across the contacted tissue area is less than about 3 times the longer of the lengths of the first and second zones.