Steerable ablation catheter

A system for ablating target tissue, the system comprising:

• an elongate anchor shaft having a proximal portion a distal portion, and a lumen extending therebetween;
• a radially expandable member coupled to the distal portion of the elongate anchor shaft, wherein the radially expandable member has a collapsed configuration for delivery and an expanded configuration for engagement with the target tissue, and wherein in the expanded configuration the radially expandable member is configured to contact the target tissue to provide anchoring thereof and to facilitate visualization of the target tissue;
• an elongate ablation shaft having a proximal portion, a distal portion, and a lumen extending therebetween, wherein the elongate ablation shaft is slidably disposed in the lumen of the elongate anchor shaft, and
• wherein the distal portion of the elongate ablation shaft is steerable;
• an energy source coupled to the distal portion of the elongate ablation shaft, the energy source configured to deliver energy to the target tissue and ablate the target tissue, wherein the energy source comprises an ultrasound transducer configured to emit ultrasound energy therefrom, and
• wherein actuation of the distal portion of the elongate ablation shaft directs the energy to the target tissue to form a desired ablation path in the target tissue;
• and
• a header element disposed between the ultrasound transducer and the distal portion of the elongate ablation shaft.

A system for ablating target tissue, the system comprising:

• an elongate anchor shaft having a proximal portion a distal portion, and a lumen extending therebetween;
• a radially expandable member coupled to the distal portion of the elongate anchor shaft, wherein the radially expandable member has a collapsed configuration for delivery and an expanded configuration for engagement with the target tissue, and wherein in the expanded configuration the radially expandable member is configured to contact the target tissue to provide anchoring thereof and to facilitate visualization of the target tissue;
• an elongate ablation shaft having a proximal portion, a distal portion, and a lumen extending therebetween, wherein the elongate ablation shaft is slidably disposed in the lumen of the elongate anchor shaft, and
• wherein the distal portion of the elongate ablation shaft is steerable;
• an energy source coupled to the distal portion of the elongate ablation shaft, the energy source configured to deliver energy to the target tissue and ablate the target tissue, and
• wherein actuation of the distal portion of the elongate ablation shaft directs the energy to the target tissue to form a desired ablation path in the target tissue;
• and
• a plurality of pull wires disposed in the elongate ablation shaft and coupled to the distal portion of the elongate ablation shaft, wherein actuation of one or more of the plurality of pull wires steers the distal portion of the elongate ablation shaft,
• wherein at least one of the plurality of pull wires comprises a first free end, a second free end, and an intermediate portion therebetween, wherein the first free is disposed adjacent a proximal end of the ablation shaft, the intermediate portion extends along the ablation shaft, across a distal portion of the ablation shaft, and returns along the ablation shaft so that the second free end is disposed adjacent the proximal end of the ablation shaft.