# US 2018/0021546 A1 · High load steerable shaft and method for cardiac catheter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0021546 A1 - Document ID: US20180021546A1 - Status: Published application - Kind: A1 - Application number: 15/648,635 - Filed: 2017-07-13 - Published: 2018-01-25 - Earliest claimed: 2016-07-21 - Assignees: Creganna Unlimited Company - Applicants: Creganna Unlimited Company - Inventors: Bernard McDermott; Adam Szczepanski - Web page: https://patentgrep.com/patent/US20180021546A1 ## CPC - A61M 25/0144: {having flexible regions as a result of inner reinforcement means, e.g. struts or rods} - A61M 25/0133: {Tip steering devices} - A61M 25/0138: {having flexible regions as a result of weakened outer material, e.g. slots, slits, cuts, joints or coils} - A61M 25/0147: {with movable mechanical means, e.g. pull wires} - A61M 25/09: Guide wires - A61M 25/09033: {with fixed mandrils, e.g. mandrils fixed to tip; Tensionable wires} - A61M 2025/0161: {wherein the distal tips have two or more deflection regions} - A61M 2025/09175: {having specific characteristics at the distal tip} - 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)} ## Abstract A tube or skeleton for a steerable catheter includes a cylindrical body structured to permit bending in at least one bending direction and to resist bending in directions transverse to the bending direction. The cylindrical body may include a laser cut metal tube, wires bent and connected to one another, or one or more coiled wires with axial support wires attached to the coil to define one or more bending directions to form bending segments. The skeleton includes axially stiff portions that resist compression when a pull wire is pulled to cause bending movement. The axially stiff portions may include a backbone, an alignment of pivot structures, connected axially extending portions of wire elements, or axially extending support wires or rods. Two or more bending portions may be provided, each with different bending directions. Complex bending shapes may be provided by arranging the segments in rotated positions along the skeleton. ## Claims ### Claim 1 A skeleton for a catheter, comprising: a bending portion including a cylindrical body having a first end and a second end, the bending portion being structured to bend in a predetermined bending direction, the bending portion including a plurality of segments arranged sequentially adjacent one another in the bending portion, an axial support structure extending along at least one side of the cylindrical body, the axial support structure being flexible to permit bending in the predetermined bending direction but being resistant to compression in an axial direction; and the bending portion being configured for receiving a pull wire extending along an inside wall of the cylindrical body in a direction of the predetermined bending direction with the pull wire anchored at the first end and extending beyond the second end for receiving a pulling force, the bending portion being configured to bend in the predetermined direction in response to the pulling force exerted on the pull wire. ### Claim 2 (depends on 1) A skeleton as claimed in claim 1, wherein the bending portion is formed of a metal tube. ### Claim 3 (depends on 2) A skeleton as claimed in claim 2, wherein the metal tube includes a backbone portion as the axial support structure and a plurality of wide cuts into the metal tube opposite the backbone structure to form the segments. ### Claim 4 (depends on 2) A skeleton as claimed in claim 2, wherein the metal tube includes pivot structures as the axial support structure, the pivot structures connecting each of the segments to one another, the pivot structures being disposed on opposite sides of the cylindrical body. ### Claim 5 (depends on 1) A skeleton as claimed in claim 1, wherein the bending portion includes first and second wires formed into segments, the axial support structure including axially extending portions of the first and second wires joined to one another. ### Claim 6 (depends on 1) A skeleton as claimed in claim 1, wherein the bending portion includes a coiled wire providing the cylindrical body, and wherein the axial support structures includes at least one axial support wire or rod connected to the coiled wire along a side of the cylindrical body. ### Claim 7 (depends on 6) A skeleton as claimed in claim 6, wherein the axial support structure includes two axial support wires or rods extending along opposite sides of the cylindrical body and connected to the coiled wire. ### Claim 8 (depends on 1) A skeleton as claimed in claim 1, further comprising: a ring connected to the first end of the cylindrical body. ### Claim 9 (depends on 1) A skeleton as claimed in claim 1, wherein the bending portion is a first bending portion, and further comprising: a second bending portion connected to the first bending portion, the second bending portion having a predetermined bending direction different than the predetermined bending direction of the first bending portion. ### Claim 10 (depends on 9) A skeleton as claimed in claim 9, further comprising: a ring connected between the first and second bending portions. ### Claim 11 (depends on 1) A skeleton as claimed in claim 1, wherein the structures of the segments are rotated about the axis of the cylindrical body relative to one another to provide a complex bending shape for the bending portion. ### Claim 12 A method for guiding a catheter, comprising: bending a portion of a cylindrical body having a first end and a second end, the bending occurring at a bending portion structured to bend in a predetermined bending direction, the bending portion including a plurality of segments arranged sequentially adjacent one another in the bending portion, axially supporting at least one side of the cylindrical body, the axially supporting permitting flexing to permit bending in the predetermined bending direction but being resistant to compression in an axial direction; and receiving a pull wire extending along an inside wall of the bending portion of the cylindrical body in a direction of the predetermined bending direction with the pull wire anchored at the first end and extending beyond the second end for receiving a pulling force, the bending portion being configured to bend in the predetermined direction in response to the pulling force exerted on the pull wire.