Linear ablation devices and methods of use

Abstract

Described herein are various methods and devices for delivering cryoablative therapy. Various ablative patterns can be produced by the devices, including, linear ablation patterns. One exemplary device includes a cryoablation chamber and a volume displacement chamber. In use, the volume displacement chamber can be expanded to support the cryoablation chamber.

We claim: 
     
         1 . A method of cryoablating tissue comprising the steps of:
 providing a catheter device comprising a catheter shaft and an expandable body comprising a first chamber;   positioning the expandable body relative to target tissue;   delivering cryofluid into the first expandable chamber; and   forming a linear ablation pattern adjacent to the first chamber.   
     
     
         2 . The method of  claim 1 , wherein the linear ablation pattern extends at least partially around the entrance to the pulmonary veins. 
     
     
         3 . The method of  claim 1 , wherein the linear ablation pattern is formed in cardiac tissue. 
     
     
         4 . The method of  claim 1 , wherein the linear ablation pattern corresponds to at least a portion of a Maze-Cox pattern. 
     
     
         5 . The method of  claim 1 , wherein the expandable body is positioned within the atria. 
     
     
         6 . The method of  claim 1 , wherein delivering cryofluid into the first chamber expands the first chamber. 
     
     
         7 . The method of  claim 1 , further comprising a second chamber and the step of filling the second chamber with a volume displacement fluid. 
     
     
         8 . The method of  claim 7 , wherein the step of filling the second chamber occurs prior to the step of delivering cryofluid. 
     
     
         9 . The method of  claim 7 , wherein the step of filling the second chamber cause the expandable body to substantially occupy the volume of an anatomic chamber. 
     
     
         10 . The method of  claim 1 , further comprising the step of cardiac mapping using the catheter device. 
     
     
         11 . A method of cryoablating tissue comprising the steps of:
 providing a catheter device comprising a catheter shaft and an expandable body comprising a first chamber and a second chamber;   expanding the expandable body by delivering a volume expansion fluid to the second chamber;   delivering cryofluid into the first expandable chamber when the expandable body is exanded; and   ablating tissue adjacent to the first chamber.   
     
     
         12 . The method of  claim 11 , wherein the volume expansion fluid is not a cryofluid. 
     
     
         13 . The method of  claim 11 , wherein ablating tissue adjacent to the first chamber comprises forming a linear ablation pattern 
     
     
         14 . The method of  claim 11 , wherein the first chamber is positioned on the second chamber. 
     
     
         15 . The method of  claim 11 , wherein the expandable body is expanded prior to the delivering of the cryofluid. 
     
     
         16 . The method of  claim 11 , wherein the expanding of the expandable body causes the expandable body to substantially occupy the volume of an anatomic chamber. 
     
     
         17 . The method of  claim 11 , wherein the ablated tissue is cardiac tissue. 
     
     
         18 . The method of  claim 11 , wherein the first chamber does not enclose the second chamber. 
     
     
         19 . A method of cryoablating tissue comprising the steps of:
 providing a catheter device comprising a catheter shaft and a first chamber;   delivering cryofluid into the first expandable chamber, the delivery of the cryofluid causing the first chamber to move from a first, low profile delivery configuration to an expanded configuration; and   ablating tissue adjacent to the first chamber.   
     
     
         20 . The method of  claim 19 , wherein the expanded configuration of the first chamber is positioned for producing a linear ablation pattern.