Abstract: A device for treating tissue has a plurality of conductors that form one or more transmission lines configured to deliver microwave energy to target tissue. In addition to transmission lines, the device also may include an anchor element used to penetrate the target ablation tissue and anchor the device. A system includes the device, a microwave generator, and a coaxial cable. A biocompatible solution may be injected into the target ablation region to alter tissue properties or to facilitate visualization of the ablation region.

Abstract: Methods for treating anatomic tissue defects such as a patent foramen ovale generally involve positioning a distal end of a catheter device at the site of the defect, exposing a housing and energy transmission member from the distal end of the catheter, engaging the housing with tissues at the site of the defect, applying suction or other approximating tool to the tissue via the housing to bring the tissue together, and applying energy to the tissue with the energy transmission member or to deliver a clip or fixation device to substantially close the defect. Apparatus generally include a catheter body, a housing extending from a distal end of the catheter body for engaging tissue at the site of the defect, and further adapted to house a fusing or fixation device such as an energy transmission member adjacent a distal end of the housing, or a clip or fixation delivery element.