# US 11,759,608 B2 · Intravascular fluid catheter with minimal internal fluid volume > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,759,608 B2 - Document ID: US11759608B2 - Status: Granted - Kind: B2 - Application number: 16/805,033 - Filed: 2020-02-28 - Published: 2020-08-27 - Granted: 2023-09-19 - Earliest claimed: 2011-08-24 - Assignees: Ablative Solutions, Inc. - Applicants: Ablative Solutions, Inc. - Inventors: David R. Fischell; Tim A. Fischell - Web page: https://patentgrep.com/patent/US11759608B2 ## CPC - A61M 25/0084: {being one or more injection needles} - A61B 5/24: Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof - A61B 5/6876: {Blood vessel} - A61M 25/0074: {Dynamic characteristics of the catheter tip, e.g. openable, closable, expandable or deformable} - A61M 25/0108: {using radio-opaque or ultrasound markers} - A61M 25/0662: {Guide tubes} - A61B 5/6848: {Needles} - A61B 2505/05: Surgical care - A61B 2562/0209: Special features of electrodes classified in A61B5/24, A61B5/25, A61B5/283, A61B5/291, A61B5/296, A61B5/053 - A61M 25/0097: {characterised by the hub (tube connectors or tube couplings A61M39/10)} - A61M 2025/0039: {characterized by lumina being arranged coaxially} - A61M 2025/0086: {the needles having bent tips, i.e. the needle distal tips are angled in relation to the longitudinal axis of the catheter} - A61M 2025/0087: {Multiple injection needles protruding laterally from the distal tip} - A61M 2025/0681: {Systems with catheter and outer tubing, e.g. sheath, sleeve or guide tube} - A61M 2202/0468: non-physiological - A61M 2210/12: Blood circulatory system - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A catheter-based/intravascular ablation (denervation) system includes a multiplicity of needles which expand open around a central axis to engage the wall of a blood vessel, or the wall of the left atrium, allowing the injection of a cytotoxic or/or neurotoxic solution for ablating conducting tissue, or nerve fibers around the ostium of the pulmonary vein, or circumferentially in or just beyond the outer layer of the renal artery. The expandable needle delivery system is formed with self-expanding materials and include structures, near the end portion of the needles, or using separate guide tubes. The system also includes means to limit and/or adjust the depth of penetration of the ablative fluid into the tissue of the wall of the targeted blood vessel. The preferred embodiment of the catheter delivered through the vascular system of a patient includes a multiplicity of expandable guide tubes that engage the wall of a blood vessel. Injection needles having injection egress at or near their sharpened distal end are then advanced through the guide tubes to penetrate the wall of the blood vessel to a prescribed depth. The ability to provide PeriVascular injection so as to only affect the outer layer(s) of a blood vessel without affecting the media has particular application for PeriVascular Renal Denervation (PVRD) of the sympathetic nerves which lie in the adventitia or outside the adventitia of the renal artery. ## Claims ### Claim 1 A method comprising: providing a system comprising a catheter body, a first guide tube, a second guide tube, a third guide tube, a first injection needle, a second injection needle, and a third injection needle, the first injection needle disposed within a lumen of the first guide tube, the second injection needle disposed within a lumen of the second guide tube, the third injection needle disposed within a lumen of the third guide tube; simultaneously advancing the first guide tube, the second guide tube, and the third guide tube to curve outward toward a target wall of a target vessel but not penetrate the target wall of the target vessel; simultaneously advancing the first injection needle, the second injection needle, and the third injection needle to penetrate the target wall, guided by the first guide tube, the second guide tube, and the third guide tube, each injection needle extending beyond the respective guide tube until further advancement of the injection needles is prevented; and delivering an ablative fluid through the first injection needle, the second injection needle, and the third injection needle to form an ablation zone of ablative fluid for each injection needle, wherein the ablation zones of ablative fluid intersect to form an ablative ring of ablative fluid around a circumference of the target vessel. ### Claim 2 (depends on 1) The method of claim 1, further including visualization of a radiopaque marker. ### Claim 3 (depends on 1) The method of claim 1, further including visualization of a radiopaque marker of the first guide tube. ### Claim 4 (depends on 1) The method of claim 1, further including visualization of a radiopaque marker of the first injection needle. ### Claim 5 (depends on 1) The method of claim 1, further including visualization of a radiopaque wire within the first injection needle. ### Claim 6 (depends on 1) The method of claim 1, further including evaluating electrical activity with the first injection needle. ### Claim 7 (depends on 1) The method of claim 1, further including measuring electrical activity within the target wall with the first injection needle. ### Claim 8 (depends on 1) The method of claim 1, wherein the first and second injection needles advance at least 0.5 mm beyond the respective guide tubes. ### Claim 9 (depends on 1) The method of claim 1, wherein the first and second injection needles advance between 0.5 mm and 4 mm beyond the respective guide tubes. ### Claim 10 (depends on 1) The method of claim 1, wherein the first and second injection needles advance between 2 mm and 3 mm beyond the respective guide tubes. ### Claim 11 A method comprising: providing a system comprising a catheter body, a first guide tube, a second guide tube, a third guide tube, a first injection needle, a second injection needle, and a third injection needle, the first injection needle disposed within a lumen of the first guide tube, the second injection needle disposed within a lumen of the second guide tube, the third injection needle disposed within a lumen of the third guide tube; simultaneously advancing the first guide tube, the second guide tube, and the third guide tube to curve outward against a target wall but not penetrate the target wall; simultaneously advancing the first injection needle, the second injection needle, and the third injection needle relative to and within the lumens of the first guide tube, the second guide tube, and the third guide tube, respectively, to penetrate the target wall, each injection needle extending beyond the respective guide tube to penetrate the target wall at a preset distance; and delivering an ablative fluid through the first injection needle, the second injection needle, and the third injection needle to produce a ring of ablative fluid causing circumferential damage in nerve tissue near the target wall. ### Claim 12 (depends on 11) The method of claim 11, further including visualization of the first guide tube, the second guide tube, or the first and second guide tubes. ### Claim 13 (depends on 11) The method of claim 11, further including visualization of the first injection needle, the second injection needle, or the first and second injection needles. ### Claim 14 (depends on 11) The method of claim 11, wherein the preset distance is 0.5 mm. ### Claim 15 (depends on 11) The method of claim 11, wherein the preset distance is between 0.5 mm and 4 mm. ### Claim 16 (depends on 11) The method of claim 11, wherein the preset distance is between 2 mm and 3 mm. ### Claim 17 (depends on 11) The method of claim 11, wherein the preset distance is determined prior to advancing the system in a body of a patient. ### Claim 18 (depends on 11) The method of claim 11, wherein the preset distance is determined by a measurement of anatomy of a patient. ### Claim 19 A method comprising: providing a system comprising a catheter body, three guide tubes, three injection needles, each injection needle adapted to move distally and proximally relative to and within a lumen of a respective guide tube of the three guide tubes; simultaneously advancing the three guide tubes against a target wall but not penetrate the target wall; simultaneously advancing the three injection needles, each injection needle advancing relative to the respective guide tube of the three guide tubes to penetrate the target wall, each injection needle extending beyond the respective guide tube up to a maximum distance; and delivering an ablative fluid through the three injection needles to form a ring of ablative fluid causing ablation of sympathetic nerve fibers beyond the target wall. ### Claim 20 (depends on 19) The method of claim 19, wherein each injection needle advances at least 0.5 mm beyond the respective guide tube.