Devices and methods for creating continuous lesions

Abstract

The present invention discloses devices and methods for creating multiple lesions using ablation devices in anatomical regions such as the heart, for example to treat cardiac arrhythmias. The present invention discloses methods and devices to create continuous lesions using area ablation devices. The present invention discloses various embodiments of reference assemblies for accurately positioning ablation devices having ablating portions, especially deployable ablation portions adapted for area ablation. The ablation devices are positioned using the reference assemblies in the anatomy to create one or more lesions. The present invention also discloses several method embodiments for creating continuous lesions using deployable ablating portions to produce two or more overlapping lesions.

1 . An ablation system for ablating a biological tissue comprising:
 a closed-loop reference assembly defining a first profile,   an elongated ablation device having an ablating portion, the ablating portion adapted to be deployed from a relatively linear un-deployed first configuration to a relatively non-linear deployed second configuration, wherein the second configuration defines a second profile spatially separated from the first profile, and   a deployment member from which the ablating portion can be deployed, wherein the deployment member is located along the closed loop reference assembly.   
     
     
         2 . (canceled) 
     
     
         3 . The ablation system of  claim 1 , wherein the ablating portion is adapted to transmit an ablative energy selected from the group consisting of RF energy, microwave energy, ultrasound energy, thermal energy, cryogenic energy and infrared energy. 
     
     
         4 . (canceled) 
     
     
         5 . (canceled) 
     
     
         6 . (canceled) 
     
     
         7 . (canceled) 
     
     
         8 . The ablation system of  claim 1  wherein the closed loop reference assembly comprises a springy member. 
     
     
         9 . (canceled) 
     
     
         10 . The ablation system of  claim 8 , wherein the closed loop reference assembly further comprises a hinge for rotatably interfacing the springy member to the remainder of the reference assembly. 
     
     
         11 . The ablation system of  claim 1 , wherein the closed loop reference assembly comprises at least one tubular member. 
     
     
         12 . The ablation system of  claim 11 , wherein the deployment member is the distal end of the at least one tubular member. 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . The ablation system of  claim 1 , wherein the ablating portion is substantially planar. 
     
     
         16 . The ablation system of  claim 1 , wherein the volume of ablating portion is unchangeable. 
     
     
         17 . The ablation system of  claim 1  wherein the reference assembly is adapted to engage at least a portion of the closed loop to an anatomical structure. 
     
     
         18 . The ablation system of  claim 17 , wherein the anatomical structure is a tissue surface of the heart. 
     
     
         19 . The ablation system of  claim 17 , wherein the anatomical structure is a pulmonary vein. 
     
     
         20 . An ablation device for ablating a biological tissue comprising:
 a) an ablating portion adapted to be deployed from a relatively linear un-deployed first configuration to a relatively non linear deployed second configuration;   b) an elongate reference element; and   c) a positioning element adapted to cooperate with the elongate reference element to define multiple relative positions of the positioning element relative to the reference element,   wherein the ablating portion is deployable from the positioning element from multiple locations along the length of the positioning element.   
     
     
         21 . The ablation device of  claim 20 , wherein the ablating portion further comprises an ablative energy transmitting element. 
     
     
         22 . (canceled) 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . The ablation device of  claim 20 , wherein the ablating portion includes a microwave antenna selected from the group consisting of circular antenna, annular antenna, elliptical antenna, loop antenna, linear antenna, curvilinear antenna and planar antenna. 
     
     
         29 . (canceled) 
     
     
         30 . (canceled) 
     
     
         31 . The ablation device of  claim 20 , wherein the positioning element comprises at least one electrode. 
     
     
         32 . The ablation device of  claim 20 , wherein the positioning element is rotatable about the reference element. 
     
     
         33 . (canceled) 
     
     
         34 . (canceled) 
     
     
         35 . (canceled) 
     
     
         36 . (canceled) 
     
     
         37 . (canceled) 
     
     
         38 . The ablation device of  claim 20 , wherein one of the multiple locations along the length of the positioning device is located proximal to the distal end of the positioning device. 
     
     
         39 . An ablation device for ablating a biological tissue comprising:
 a) a closed-loop reference assembly deployable from a low-profile, non-deployed configuration to a high-profile, deployed configuration, the loop comprising a first section and a second section wherein the first section is stiffer than the second section, such that the second section is deployable in the anatomy in multiple positions relative to the first section; and   b) an ablating portion positioned along a portion of the second section of the reference assembly,   wherein the ablating portion is adapted to be deployed from a relatively linear, non-deployed first configuration to a relatively non-linear, deployed second configuration.   
     
     
         40 . (canceled) 
     
     
         41 . (canceled) 
     
     
         42 . (canceled) 
     
     
         43 . (canceled) 
     
     
         44 . (canceled) 
     
     
         45 . (canceled) 
     
     
         46 . (canceled) 
     
     
         47 . The ablation device of  claim 39 , wherein the ablating portion includes a microwave antenna selected from the group consisting of circular antenna, annular antenna, elliptical antenna, loop antenna, linear antenna, curvilinear antenna and planar antenna. 
     
     
         48 . (canceled) 
     
     
         49 . The ablation device of  claim 39 , wherein the shape of the closed-loop reference assembly can be modified by deploying the second section while maintaining the first section stable. 
     
     
         50 . The ablation device of  claim 39 , wherein the ablating portion includes only one ablative element. 
     
     
         51 . An ablation system for ablating biological tissue at a location with respect to a reference, comprising:
 an elongate guide sheath having a distal portion and a lumen therethrough defining a distal opening, the distal portion of the guide sheath forming at least one spline portion having a distal end;   an elongate reference member having a distal portion, the elongate reference member slidably disposed within the lumen of the elongate guide sheath; and   an alignment member having first and second sections, the first section attached to the distal portion of the elongate reference member and the second section attached to the elongate guide sheath at the distal end of the at least one spline, the alignment member including an ablating portion adjacent the second section adapted to transmit ablative energy therefrom, the ablating portion including at least one ablating element; and   wherein the at least one spline portion cooperates with the alignment member to define an ablation zone at the location with respect to the reference.   
     
     
         52 . (canceled) 
     
     
         53 . (canceled) 
     
     
         54 . The ablation system of  claim 51 , wherein the distal portion of the elongate reference member includes one or more electrodes thereon for transceiving electrophysiological signals to and from biological tissue. 
     
     
         55 . The ablation system of  claim 54 , wherein the electrodes are used to determine tissue contact between the elongate reference member and the biological tissue. 
     
     
         56 . The ablation system of  claim 51 , wherein the distal portion of the elongate reference member includes at least one radio-opaque element, wherein the radio-opaque element is visible under fluoroscopy to provide an indication of the orientation of the elongate reference member with respect to the biological tissue. 
     
     
         57 . The ablation system of  claim 51 , wherein the alignment member includes at least one deflection point defined along its length. 
     
     
         58 . (canceled) 
     
     
         59 . (canceled) 
     
     
         60 . (canceled) 
     
     
         61 . The ablation system of  claim 51 , wherein the at least one ablative element is an antenna adapted to emit electromagnetic energy. 
     
     
         62 . The ablation system of  claim 51 , wherein the at least one ablative element is an electrode adapted to emit RF energy. 
     
     
         63 . The ablation system of  claim 51 , wherein the at least one ablative element is positioned at least between the alignment member and the biological tissue, the alignment member encouraging contact between the at least one ablative element and the biological tissue. 
     
     
         64 . The ablation system of  claim 51 , wherein the alignment member includes at least one electrode thereon for acquiring electrophysiological information from the biological tissue. 
     
     
         65 . The ablation system of  claim 64 , wherein the information received is used to assess the ablation of the biological tissue. 
     
     
         66 . The ablation system of  claim 61 , wherein the ablating portion is linear. 
     
     
         67 . The ablation system of  claim 66 , wherein the antenna is positioned along an alignment member surface. 
     
     
         68 . The ablation system of  claim 51 , wherein the reference is the elongate reference member. 
     
     
         69 . The ablation system of  claim 51 , wherein the reference is an anatomical structure. 
     
     
         70 . (canceled) 
     
     
         71 . (canceled) 
     
     
         72 . (canceled) 
     
     
         73 . (canceled)