Ablation catheter

Abstract

Devices, systems and methods are disclosed for the mapping of electrical signals and the ablation of tissue. Embodiments include an ablation catheter that has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be transformed from a compact, linear configuration to a helical configuration, such as to map and ablate pulmonary vein ostia.

What is claimed is: 
     
         1 . A medical device, the device comprising:
 an elongate body defining a distal portion, a proximal portion, and a lumen extending from the distal portion to the proximal portion;   a first control shaft extending through the elongate body lumen, the first control shaft including a distal portion and a proximal portion;   a second control shaft extending through the elongate body lumen, the second control shaft including a distal portion, a proximal portion, and a lumen extending within at least a portion of the distal portion of the second control shaft; and   an electrode array including a first plurality of carrier arms and a second plurality of carrier arms, each carrier arm of the first plurality of carrier arms and the second plurality of carrier arms including a proximal portion and a distal portion, the proximal portion of each of the first plurality of carrier arms being coupled to the distal portion of the elongate body, the distal portion of each of the first plurality of carrier arms being coupled to the distal portion of the first control shaft, at least a portion of the proximal portion of each of the second plurality of carrier arms being located within the second control shaft, and the distal portion of each of the second plurality of carrier arms being coupled to the distal portion of the first control shaft.   
     
     
         2 . The device of  claim 1 , wherein the first control shaft and the second control shaft are longitudinally movable within the elongate body lumen. 
     
     
         3 . The device of  claim 1 , wherein the first control shaft and the second control shaft are longitudinally movable within the elongate body lumen independently of each other. 
     
     
         4 . The device of  claim 3 , wherein longitudinal movement of the second control shaft toward the distal portion of the first control shaft causes the second plurality of carrier arms to move toward each other. 
     
     
         5 . The device of  claim 1 , wherein the electrode array is transitionable between a first configuration and a second configuration, each of the first and second plurality of carrier arms being in an at least substantially linear configuration when the electrode array is in the first configuration. 
     
     
         6 . The device of  claim 1 , wherein the second control shaft is longitudinally movable between a proximal first position and a distal second position. 
     
     
         7 . The device of  claim 6 , wherein the carrier arms of the second plurality of carrier arms are separated from each other by a first radial distance when the second control shaft is in the proximal first position and the electrode array is in the second configuration. 
     
     
         8 . The device of  claim 7 , wherein the carrier arms of the second plurality of carrier arms are separated from each other by a second radial distance when the second control shaft is in the distal second position and the electrode array is in the second configuration, the first radial distance being greater than the second radial distance. 
     
     
         9 . The device of  claim 1 , wherein the second control shaft is longitudinally movable within the elongate body lumen between a distal position and a proximal position, the second control shaft being configured to move the proximal portion of each of the second plurality of carrier arms toward each other as the second control shaft is moved toward the distal position. 
     
     
         10 . The device of  claim 1 , wherein at least one carrier arm of the first plurality of carrier arms includes an electrode. 
     
     
         11 . The device of  claim 1 , wherein at least one carrier arm of the second plurality of carrier arms includes an electrode. 
     
     
         12 . The device of  claim 5 , wherein retraction of the first control shaft within the elongate body lumen toward the proximal portion of the elongate body causes the electrode array to transition to the second electrode array configuration. 
     
     
         13 . The device of  claim 12 , wherein each carrier arm of the first and second plurality of carrier arms has an arcuate configuration when the electrode array is in the second electrode array configuration. 
     
     
         14 . A medical device, the device comprising:
 an elongate body including a distal portion, a proximal portion, and a lumen extending from the distal portion to the proximal portion;   a first control shaft extending through and being longitudinally movable within the elongate body lumen, the first control shaft including a distal portion, a proximal portion, and a longitudinal axis;   a second control shaft extending through and being longitudinally movable within the elongate body lumen, the second control shaft including a distal portion, a proximal portion, a longitudinal axis, and a lumen, the longitudinal axis of the first control shaft and the longitudinal axis of the second control shaft being at least substantially parallel, the first control shaft and the second control shaft being longitudinally movable within the elongate body independently of each other; and   an electrode array including a plurality of carrier arms, each of the plurality of carrier arms having a distal portion and a proximal portion, the distal portion of each of the plurality of carrier arms being coupled to the distal portion of the first control shaft, the proximal portion of at least two of the plurality of carrier arms being within the lumen of the second control shaft, a remainder of the plurality of carrier arms being coupled to the distal portion of the first control shaft, movement of the second control shaft toward the distal end of the first control shaft causing the at least two of the plurality of carrier arms to move toward each other.   
     
     
         15 . The device of  claim 14 , wherein at least one of the plurality of carrier arms includes an electrode. 
     
     
         16 . The device of  claim 14 , wherein retraction of the first control shaft within the elongate body lumen toward the proximal portion of the elongate body causes the electrode array to have an expanded configuration. 
     
     
         17 . A medical device, the device comprising:
 an elongate body defining a distal portion, a proximal portion, and a lumen extending from the proximal portion to the distal portion;   a shaft extending through the lumen, the shaft defining a distal portion and a proximal portion;   a ring coupled to the distal portion of the shaft; and   an electrode array including a plurality of carrier arms and defining a distal portion and a proximal portion, the proximal portion of the electrode array being coupled to an inner surface of the elongate body lumen and the distal portion of the electrode array being coupled to the distal portion of the shaft, the plurality of carrier arms being radially arranged around the ring.   
     
     
         18 . The device of  claim 17 , wherein the ring includes an outer edge having a circumference, the outer edge defining a plurality of notches radially arranged around the circumference of the outer edge. 
     
     
         19 . The device of  claim 18 , wherein the plurality of carrier arms includes eight carrier arms and the plurality of notches includes eight notches, each carrier arm being in a corresponding notch. 
     
     
         20 . The device of  claim 19 , wherein the eight notches includes a first notch, a second notch opposite the first notch, a third notch between the first and second notches, a fourth notch opposite the third notch, a fifth notch and a sixth notch on either side of the third notch, and a seventh notch and an eighth notch on either side of the fourth notch.