Abstract: A catheter adapted for mapping near a tubular region of a heart, has an elongated tubular catheter body having proximal and distal ends, an intermediate section distal of the catheter body, and a mapping assembly at the distal end of the intermediate section. The electrode-carrying mapping assembly has a generally circular main segment with a support member having shape-memory, and a generally linear proximal segment which has greater flexibility than either the intermediate section or the generally circular main segment. The generally circular main segment is adapted to releasably anchor itself in the tubular region and to map circumferentially around the tubular region and the generally linear segment is adapted to contact generally along its length heart wall tissue near an ostium of the tubular region.

Abstract: The invention is directed to a catheter that creates enhanced lesions using a needle electrode and can simultaneously map electrical activity at a plurality of points using an enhanced mapping assembly. The catheter comprises an elongated catheter body having at least one lumen extending longitudinally therethrough. A needle control handle is provided at the proximal end of the catheter body. A needle electrode assembly extends through the catheter body and needle control handle and has a proximal end attached to the needle control handle and a distal end within the distal end of the catheter body. A mapping assembly is mounted at the distal end of the catheter body and comprises at least two flexible spines. Each spine has a proximal end attached at the distal end of the catheter body and a free distal end. Each spine carries at least one electrode. The distal end of the needle electrode assembly is extendable past the proximal end of the mapping assembly upon manipulation of the needle control handle.

Abstract: A method for ablating tissue in or around the heart to create an enhanced lesion is provided. The distal end of a catheter including a needle electrode at its distal end is introduced into the heart. The distal end of the needle electrode is introduced into the tissue. An electrically-conductive fluid is infused through the needle electrode and into the tissue. The tissue is ablated after and/or during introduction of the fluid into the tissue. The fluid conducts ablation energy within the tissue to create a larger lesion than would be created without the introduction of the fluid.

Abstract: The invention is directed to a catheter that creates enhanced lesions using a needle electrode and can simultaneously map electrical activity at a plurality of points using an enhanced mapping assembly. The catheter comprises an elongated catheter body having at least one lumen extending longitudinally therethrough. A needle control handle is provided at the proximal end of the catheter body. A needle electrode assembly extends through the catheter body and needle control handle and has a proximal end attached to the needle control handle and a distal end within the distal end of the catheter body. A mapping assembly is mounted at the distal end of the catheter body and comprises at least two flexible spines. Each spine has a proximal end attached at the distal end of the catheter body and a free distal end. Each spine carries at least one electrode. The distal end of the needle electrode assembly is extendable past the proximal end of the mapping assembly upon manipulation of the needle control handle.