Devices and methods for ablation of tissue

Abstract

Devices and methods for the treatment of heart conditions, hypertension, and other medical disorders are described. For example, this document describes devices and methods for treating atrial fibrillation by performing thoracic vein ablation procedures, including pulmonary vein myocardium ablation. In some embodiments, the ablation is performed in coordination with the delivery a pharmacological agent that can abate the formation of tissue stenosis or neointimal hyperplasia caused by the ablation. Additionally, in some embodiments, particulate matter, such as thrombus or crystalline drug compounds, created during the ablation is captured and removed from the patient using devices and methods provided herein. Further, devices and methods for non-thermal methods of causing cell death, such as tissue suction and tissue stretching, are also described.

1 . A catheter-based system for treating a tissue, the system comprising:
 an ablation catheter device comprising:
 an elongate catheter shaft including a liquid delivery lumen therethrough; 
 a balloon device disposed at a distal end portion of said catheter shaft, said balloon device comprising an outer surface and an inner surface, said inner surface defining an interior space of said balloon device, said balloon device in fluid communication with said liquid delivery lumen, said balloon device comprising a porous or microporous material that is arranged to transmit a liquid through said porous or microporous material; and 
 one or more electrodes that are disposed on or within said balloon device and are arranged to deliver energy to said tissue; and 
   a catheter defining a lumen, the ablation catheter device being slidably disposed within the lumen, the catheter including an expandable distal end portion.   
     
     
         2 . The catheter-based medical device of  claim 1 , wherein said one or more electrodes is a single electrode disposed on said catheter shaft and in said interior space. 
     
     
         3 . The catheter-based medical device of  claim 1 , wherein said one or more electrodes is a plurality of electrodes disposed on said outer surface. 
     
     
         4 . The catheter-based medical device of  claim 3 , wherein said plurality of electrodes comprise at least one electrode that is arranged to transmit radio frequency energy for ablation of said tissue and at least one electrode that is arranged to transmit direct current electrical energy. 
     
     
         5 . The catheter-based medical device of  claim 1 , wherein said one or more electrodes comprises (i) a single electrode disposed on said catheter shaft and in said interior space and (ii) plurality of electrodes disposed on said outer surface. 
     
     
         6 . The catheter-based medical device of  claim 5 , wherein said single electrode is arranged to transmit radio frequency energy for ablation of said tissue, and said plurality of electrodes comprise at least one electrode that is arranged to transmit direct current electrical energy. 
     
     
         7 . A method for treating a tissue of a patient, said method comprising:
 inserting a catheter-based system into said patient, said system comprising:
 an ablation catheter device; and 
 a catheter defining a lumen, the ablation catheter device being slidably disposed within the lumen, the catheter including an expandable distal end portion; 
   deploying said ablation catheter device near said tissue;   expanding said expandable distal end portion;   deploying said expanded expandable distal end portion against a tissue wall to enclose a space adjacent at least a portion of said ablation catheter device;   supplying ablation energy to said ablation catheter device; and   suctioning said space via said catheter.   
     
     
         8 . The method of  claim 7 , wherein said tissue is a pulmonary vein. 
     
     
         9 . The method of  claim 7 , wherein said tissue is a renal artery. 
     
     
         10 . The method of  claim 7 , further comprising, after said suctioning, irrigating said space with an irrigant supplied via said catheter. 
     
     
         11 . The method of  claim 10 , further comprising, after said irrigating, suctioning said space via said catheter. 
     
     
         12 . A catheter-based system for treating a tissue, the system comprising:
 a double-balloon catheter comprising:
 a catheter shaft; 
 a proximal inflatable member attached to the catheter shaft; and 
 a distal inflatable member attached to the catheter shaft at a location that is distally spaced apart from the proximal inflatable member, 
   wherein the catheter shaft includes a lumen that defines an opening at a location between the proximal inflatable member and the distal inflatable member.   
     
     
         13 . The system of  claim 12 , further comprising a delivery sheath defining a lumen, wherein the double-balloon catheter is slidably disposed within the lumen. 
     
     
         14 .- 17 . (canceled)