Cryosurgical ablation device having sequential injection and method therefor

Abstract

A device and method for cryosurgical ablation. A tip has a thermally transmissive region along a length thereof in which the thermally transmissive region is operable at a temperature sufficient to cryosurgically ablate tissue in contact therewith. A plurality of cryosurgical fluid injection lumens each have a first end positioned within the tip at a different point along the length of the thermally transmissive region. Each of the first ends is arranged to cool overlapping respective portions along the length of the thermally transmissive region when cryogenic fluid is ejected from the plurality of cryogenic fluid injection lumens.

What is claimed is:  
     
         1 . A device for cryosurgical ablation, comprising: 
 a tip having a thermally transmissive region along a length thereof, the thermally transmissive region being operable at a temperature sufficient to cryosurgically ablate tissue in contact therewith;    a plurality of cryosurgical fluid injection lumens, each of the plurality of cryosurgical injection lumens having a first end positioned within the tip at a different point along the length of the thermally transmissive region,    each of the first ends being arranged to cool overlapping respective portions along the length of the thermally transmissive region when cryogenic fluid is ejected from the plurality of cryogenic fluid injection lumens.    
     
     
         2 . The device according to  claim 1 , wherein each of the plurality of cryogenic fluid injection lumens further comprises a second end opposite the first end, and wherein the device further comprises a plurality of valves, each of the plurality of valves having an output in fluid communication with the second end of a corresponding cryogenic fluid injection lumen.  
     
     
         3 . The device according to  claim 2 , wherein the plurality of valves are electrically actuable.  
     
     
         4 . The device according to  claim 2 , wherein the device further comprises a handle having an inner volume and wherein each of the plurality of valves processor is positioned within the inner volume.  
     
     
         5 . The device according to  claim 2 , further comprising a cryogenic fluid distributor, the cryogenic fluid distributor having: 
 an input for receiving a flow of cryogenic fluid; and    a plurality of outputs in fluid communication with a respective valve,    the cryogenic fluid distributor receiving the flow of cryogenic fluid and substantially evenly distributing the flow of cryogenic fluid to each of the plurality of valves.    
     
     
         6 . The device according to  claim 5 , wherein the device further comprises a handle having an inner volume and wherein the fluid distributor is positioned within the inner volume.  
     
     
         7 . The device according to  claim 2 , wherein the plurality of valves are individually sequentially actuable.  
     
     
         8 . The device according to  claim 1 , wherein each of the plurality of cryogenic fluid injection lumens further comprises a second end opposite the first end, and wherein the device further comprises a valve assembly having: 
 a plurality of electrically actuable valves, each of the plurality of electrically actuable valves having an output in fluid communication with the second end of a corresponding cryogenic fluid injection lumen; and    a valve processor, the valve processor receiving at least one electronic valve actuation signal and controlling the actuation of the plurality of valves in accordance with the received at least one electronic valve actuation signal.    
     
     
         9 . The device according to  claim 8 , wherein the plurality of electrically actuable valves are piezo-electric valves.  
     
     
         10 . The device according to  claim 8 , wherein the device further comprises a handle having an inner volume and wherein the valve processor is positioned within the inner volume.  
     
     
         11 . The device according to  claim 8 , further comprising a cryogenic fluid distributor, the cryogenic fluid distributor having: 
 an input for receiving a flow of cryogenic fluid; and    a plurality of outputs in fluid communication with a respective valve within the valve assembly,    the fluid distributor receiving the flow of cryogenic fluid and substantially evenly distributing the flow of cryogenic fluid to each of the plurality of valves within the valve assembly.    
     
     
         12 . The device according to  claim 11 , wherein the device further comprises a handle having an inner volume and wherein the fluid distributor is positioned within the inner volume.  
     
     
         13 . The device according to  claim 8 , wherein the valve processor is operable to sequentially actuate the plurality of valves.  
     
     
         14 . The device according to  claim 1 , wherein each of the plurality of cryogenic fluid injection lumens further comprises a second end opposite the first end, and wherein the device further comprises an integrated fluid provisioning unit having: 
 a valve assembly, the valve assembly including: 
 a plurality of electrically actuable valves, each of the plurality of electrically actuable valves having an output in fluid communication with the second end of a corresponding cryogenic fluid injection lumen; and  
 a valve processor, the valve processor receiving at least one electronic valve actuation signal and controlling the actuation of the plurality of electrically actuable valves in accordance with the received at least one electronic valve actuation signal; and  
   a cryogenic fluid distributor, the cryogenic fluid distributor having: 
 an input for receiving a flow of cryogenic fluid; and  
 a plurality of outputs in fluid communication with a respective electrically actuable valve,  
 the fluid distributor receiving the flow of cryogenic fluid and substantially evenly distributing the flow of cryogenic fluid to each of the plurality of electrically actuable valves.  
   
     
     
         15 . The device according to  claim 14 , wherein the valve processor operates to sequentially actuate the plurality of valves.  
     
     
         16 . The device according to  claim 14 , wherein the device further comprises a handle having an inner volume and, wherein the integrated fluid provisioning unit is positioned within the inner volume.  
     
     
         17 . A method for cryosurgically ablating tissue, the method comprising: 
 positioning a cryosurgical tip at tissue to be ablated, the tip having a thermally transmissive region along a length thereof; and    sequentially injecting cryogenic fluid into the tip through a plurality of cryogenic fluid injection lumens terminating within the tip at different points along the length of the thermally transmissive region.    
     
     
         18 . The method according to  claim 17 , further comprising evacuating the sequentially injected cryogenic fluid from the tip while maintaining a negative pressure therein.  
     
     
         19 . The method according to  claim 17 , wherein the cryogenic fluid is sequentially injected into the tip by sequentially actuating a plurality of valves in fluid communication with a corresponding cryogenic fluid injection lumen.  
     
     
         20 . The method according to  claim 19 , wherein the plurality of valves are sequentially actuated in accordance with an electronic signal.  
     
     
         21 . The method according to  claim 20 , wherein the plurality of valves are piezo-electrically operated.  
     
     
         22 . The method according to  claim 17 , wherein the plurality of injection lumens are arranged into a plurality of groups, and wherein the cryogenic fluid is sequentially injected into the plurality of groups of injection lumen.  
     
     
         23 . The method according to  claim 22 , wherein the cryogenic fluid is sequentially injected into the tip by sequentially actuating groups of valves in fluid communication with the corresponding groups of cryogenic fluid injection lumen.  
     
     
         24 . A method for using cryogenic mapping to detecting an arrhythmia in cardiac tissue, the method comprising: 
 positioning a cryosurgical tip at tissue to be mapped, the tip having a thermally transmissive region along a length thereof; and    sequentially injecting cryogenic fluid into the tip through a plurality of cryogenic fluid injection lumens terminating within the tip at different points along the length of the thermally transmissive region to cryogenically map the tissue.