Patent ID: 7857808

Claim:
A method of treating body tissue, comprising: providing a catheter device, having: i) an elongate catheter body including a proximal end and a distal end and a longitudinal axis; and ii) an umbrella tip at the distal end of the elongate catheter body, the umbrella tip being movable between an expanded configuration and a contracted configuration, the umbrella tip including: a center post extending from the distal end of the elongate catheter body and having a top portion, the center post including a chamber; and a plurality of outer arms connected to the top portion of the center post, each of the plurality of outer arms having a first straight portion connected to a second straight portion at a hinge, the first straight portion including at least two sets of at least two conductive elements, wherein the at least two sets are separated by a first gap distance and the at least two conductive elements are separated by a second gap distance smaller than the first gap distance, the first straight portion lying substantially in a plane transverse to the catheter body longitudinal axis in the expanded configuration; extending the center post into the elongate catheter body in order to move the umbrella tip to the expanded configuration proximate to a target location; releasing energy from the umbrella tip at the target location; and creating a shaped ablation lesion in the target location, wherein the shaped ablation lesion includes at least one gap sized to inhibit electrical impulses to propagate therethrough.