Flexible renal nerve ablation devices and related methods of use and manufacture

Abstract

Medical devices for renal nerve ablation are disclosed. An example medical device for renal nerve ablation may include a catheter shaft having a distal region. The device may include an expandable member coupled to the distal region, a flexible circuit assembly coupled to the expandable member, and a pressure sensor disposed along the expandable member and positioned adjacent to the flexible circuit assembly. The flexible circuit assembly may include one or more pairs of bipolar electrodes and a temperature sensor.

What is claimed is: 
     
         1 . A method for treating target tissue, comprising:
 advancing a treatment device through a body lumen to a target tissue, the treatment device comprising:
 a catheter shaft having a distal region, 
 an expandable member having an outer surface coupled to the distal region, 
 a flexible circuit assembly disposed on the outer surface of the expandable member, the flexible circuit assembly comprising one or more bipolar electrode pairs, and 
 one or more pressure sensors disposed on the outer surface of the expandable member; 
   expanding the expandable member to contact the target tissue;   sensing contact between the outer surface of the expandable member and the target tissue with the one or more pressure sensors;   activating at least one of the bipolar electrode pairs in contact with the target tissue to deliver energy to the target tissue; and   adjusting a pressure level within the expandable member to maintain the contact between the outer surface of the expandable member and the target tissue.   
     
     
         2 . The method of  claim 1 , wherein the expandable member includes a compliant balloon. 
     
     
         3 . The method of  claim 2 , wherein the compliant balloon includes one of a polyether block amide and a polyurethane. 
     
     
         4 . The method of  claim 1 , wherein the flexible circuit assembly includes one or more temperature sensors disposed on the flexible circuit assembly between each of the bipolar electrode pairs. 
     
     
         5 . The method of  claim 1 , wherein the catheter shaft has a longitudinal axis and wherein at least a portion of the flexible circuit assembly is disposed at an angle relative to the longitudinal axis. 
     
     
         6 . The method of  claim 1 , wherein the catheter shaft has a longitudinal axis and wherein at least a portion of the flexible circuit assembly is helically disposed about the longitudinal axis. 
     
     
         7 . The method of  claim 1 , wherein the one or more pressure sensors include a polyethylene terephthalate (PET) foil pressure sensor. 
     
     
         8 . The method of  claim 1 , wherein at least one of the one or more pressure sensors is disposed adjacent to a proximal end region of the expandable member, a distal end region of the expandable member, or both. 
     
     
         9 . A method for treating target tissue, comprising:
 advancing a treatment device through a body lumen to a target tissue, the treatment device comprising:
 a catheter shaft having a distal region, 
 an expandable member having an outer surface coupled to the distal region, 
 a flexible circuit assembly disposed on the outer surface of the expandable member, the flexible circuit assembly comprising one or more bipolar electrode pairs, and 
 one or more pressure sensors disposed on the outer surface of the expandable member; 
   expanding the expandable member to contact the target tissue;   sensing contact between the outer surface of the expandable member and the target tissue with the one or more pressure sensors;   activating at least one of the bipolar electrode pairs in contact with the target tissue to deliver energy to the target tissue; and   adjusting power to the activated bipolar electrode pairs based on feedback from the one or more pressure sensors.   
     
     
         10 . The method of  claim 9 , wherein the expandable member includes a compliant balloon. 
     
     
         11 . The method of  claim 10 , wherein the compliant balloon includes one of a polyether block amide and a polyurethane. 
     
     
         12 . The method of  claim 9 , wherein the flexible circuit assembly includes one or more temperature sensors disposed on the flexible circuit assembly between each of the bipolar electrode pairs. 
     
     
         13 . The method of  claim 9 , wherein the catheter shaft has a longitudinal axis and wherein at least a portion of the flexible circuit assembly is disposed at an angle relative to the longitudinal axis. 
     
     
         14 . The method of  claim 9 , wherein the catheter shaft has a longitudinal axis and wherein at least a portion of the flexible circuit assembly is helically disposed about the longitudinal axis. 
     
     
         15 . The method of  claim 9 , wherein at least one of the one or more pressure sensors is disposed adjacent to a proximal end region of the expandable member, a distal end region of the expandable member, or both. 
     
     
         16 . A method for treating renal nerves, the method comprising:
 advancing a renal nerve treatment device through a blood vessel to target tissue within a renal artery, the treatment device comprising:
 a catheter shaft having a distal region, 
 a compliant balloon coupled to the distal region, 
 one or more pairs of bipolar electrodes coupled to the compliant balloon, and 
 one or more pressure sensors coupled to the compliant balloon; 
   expanding the compliant balloon;   sensing contact between the compliant balloon and the target tissue of the renal artery with the one or more pressure sensors; and   activating at least one of the one or more pairs of bipolar electrodes in contact with the target tissue to deliver energy to the target tissue.   
     
     
         17 . The method of  claim 16 , wherein the compliant balloon includes one of a polyether block amide and a polyurethane. 
     
     
         18 . The method of  claim 16 , wherein one or more temperature sensors are disposed between each of the bipolar electrode pairs. 
     
     
         19 . The method of  claim 16 , wherein the one or more pressure sensors include a polyethylene terephthalate (PET) foil pressure sensor. 
     
     
         20 . The method of  claim 16 , wherein at least one of the one or more pressure sensors is disposed adjacent to a proximal end region of the compliant balloon, a distal end region of the compliant balloon, or both.