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: An irrigated ablation catheter provides improved distribution of irrigation fluid across its tip electrode surface resulting in improved cooling and flushing of blood and proteins from the tip region. An axially directed flow of irrigation provides improved heat transfer from the tip electrode to the irrigation fluid allowing for a cooler tip electrode and larger lesions. The irrigation fluid is introduced to the catheter with improved flow by means of a standard constant flow pump. A lumen or tube within a shaft of the catheter transfers the irrigation fluid to a proximal end of the tip electrode where it exits the catheter via a flow directing member mounted on the tip electrode. In one embodiment, the flow directing member is a thin walled tube that surrounds the proximal end of the tip electrode and directs the irrigation fluid distally along an outer surface of the tip electrode.

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: An irrigated ablation catheter provides improved distribution of irrigation fluid across its tip electrode surface resulting in improved cooling and flushing of blood and proteins from the tip region. An axially directed flow of irrigation provides improved heat transfer from the tip electrode to the irrigation fluid allowing for a cooler tip electrode and larger lesions. The irrigation fluid is introduced to the catheter with improved flow by means of a standard constant flow pump. A lumen or tube within a shaft of the catheter transfers the irrigation fluid to a proximal end of the tip electrode where it exits the catheter via a flow directing member mounted on the tip electrode. In one embodiment, the flow directing member is a thin walled tube that surrounds the proximal end of the tip electrode and directs the irrigation fluid distally along an outer surface of the tip electrode.

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.

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 catheter is provided which are useful for mapping circular regions of or near the heart as well as linear regions extending from the tubular regions. The catheter comprises a catheter body, a flexible, generally linear mapping section and a generally circular mapping section. The generally circular mapping section is used to map electrical activity within a tubular region of or near the heart. The generally linear mapping section is used to concurrently map electrical activity of linear regions extending from the tubular region in which the generally circular mapping section is located.

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.

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: 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: A gas-enriched fluid is provided by the combination of a first fluid, such as a patient's blood, with a second gas-supersaturated fluid, such as an oxygen supersaturated fluid. In this example, a catheter assembly includes a portion that receives the patient's blood from a pump and that receives the oxygen supersaturated fluid from an appropriate fluid source. The oxygen supersaturated fluid is advantageously combined with the blood in an area of laminar flow, and then this gas-enriched fluid is delivered to the patient through an appropriate lumen coupled to the portion of the catheter assembly.

Abstract: A method for regulating the heart rate of a patient comprises inserting into a blood vessel of the patient a catheter having an electrode assembly at its distal end. The electrode assembly comprises a generally circular main region that is generally transverse to the axis of the catheter and on which is mounted at least one electrode. The catheter is directed to an intravascular location wherein the at least one electrode on the electrode assembly is adjacent a selected cardiac sympathetic or parasympathetic nerve. The at least one electrode is stabilized at the intravascular location. A stimulus is delivered through the at least one electrode, the stimulus being selected to stimulate the adjacent sympathetic or parasympathetic nerve to thereby cause a regulation of the patient's heart rate.

Abstract: A gas-enriched fluid is provided by the combination of a first fluid, such as a patient's blood, with a second gas-supersaturated fluid, such as an oxygen supersaturated fluid. In this example, a catheter assembly includes a portion that receives the patient's blood from a pump and that receives the oxygen supersaturated fluid from an appropriate fluid source. The oxygen supersaturated fluid is advantageously combined with the blood in an area of laminar flow, and then this gas-enriched fluid is delivered to the patient through an appropriate lumen coupled to the portion of the catheter assembly.

Abstract: A catheter for ablating tissue comprises an elongated flexible catheter body having a continuous electrode comprising a braided conductive mesh surrounding a flexible plastic tubing. In a preferred embodiment, the catheter comprises a catheter body, a tip section at the distal end of the catheter body, and an electrode assembly at the distal end of the tip section. The electrode assembly comprises a flexible plastic tubing having an outer wall with a plurality of irrigation holes extending therethrough, a generally circular main region that is generally transverse to the axis of the catheter body, a continuous electrode formed of a braided conductive mesh surrounding the flexible plastic tubing and extending over substantially all of the generally circular main region, and a support member having shape memory extending within a lumen of the flexible plastic tubing. An electrode lead wire electrically connects the continuous electrode to a source of ablation energy.

Abstract: A catheter for mapping and ablating comprises an elongated flexible body having a distal region and at least one lumen extending therethrough. A tip electrode is mounted on the distal region. The tip electrode has an exposed distal region having proximal and distal ends and an isolated region proximal to the exposed distal region. The isolated region has an outer surface provided with an electrically insulating and thermally conductive layer. A second electrode is mounted on the isolated region of the tip electrode. This mapping and ablation electrode arrangement provides discrete recording of electrical signals due to the relatively small exposed distal region while allowing the creating of larger lesions due to the large thermal mass provided by the isolated region.