# US 5,507,751 A · Locally flexible dilator sheath > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,507,751 A - Document ID: US5507751A - Status: Granted - Kind: A - Application number: 08/255,602 - Filed: 1994-06-08 - Granted: 1996-04-16 - Earliest claimed: 1988-11-09 - Assignees: Cook Pacemaker Corporation - Inventors: Louis Goode; Chun K. Lui - Web page: https://patentgrep.com/patent/US5507751A ## CPC - A61N 1/057: {Anchoring means; Means for fixing the head inside the heart} - A61B 17/221: Gripping devices in the form of loops or baskets {for gripping calculi or similar types of obstructions (surgical snare instruments A61B17/32056)} - A61B 17/320016: {Endoscopic cutting instruments, e.g. arthroscopes, resectoscopes (A61B10/0233, A61B17/29, A61B17/3207 take precedence)} - A61B 17/32075: {Pullback cutting; combined forward and pullback cutting, e.g. with cutters at both sides of the plaque} - A61B 17/3468: {for implanting or removing devices, e.g. prostheses, implants, seeds, wires (devices for implanting seeds A61M37/0069)} - A61N 1/056: {Transvascular endocardial electrode systems} - A61B 17/32053: {Punch like cutting instruments, e.g. using a cylindrical or oval knife (A61B17/326 takes precedence; trepans A61B17/1695)} - A61B 17/320708: {Curettes, e.g. hollow scraping instruments} - A61B 2017/00243: {cardiac} - A61B 2017/00247: {Making holes in the wall of the heart, e.g. laser Myocardial revascularization} - A61B 2017/00292: {mounted on or guided by flexible, e.g. catheter-like, means} - A61B 2018/00392: {Transmyocardial revascularisation} - A61N 2001/0578: {having means for removal or extraction} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A locally flexible dilator sheath (10) for separating encapsulating tissue from an implanted cardiac electrical lead. The dilator sheath includes an elongated tubular member (11) of a rigid stainless steel material, which is sized for placement of the tubular member over a cardiac lead that is implanted in the vascular system of a patient. The distal end (13) of the rigid tubular member is beveled to ease the separation of extremely tough tissue that encapsulates an implanted cardiac lead. To ease insertion around curves in the vascular system of the patient, the elongated tubular member includes a relieved portion (14). The relieved portion includes a relief pattern (15) of apertures (16,17,19,23) in the elongated tubular member. The relief apertures preferably include diametrically opposed slots (24,25) that extend perpendicularly into the tubular member. Adjacent pairs (44,45) of slots are circumferentially offset a 90.degree. angle (26) to add further lateral flexibility to the relieved portion. A polyester shrink tube (41) surrounds the relief apertures to provide integrity to the tubular member should the tubular member fracture when separating encapsulating tissue from the implanted lead. ## Claims ### Claim 1 A locally flexible dilator sheath (10) comprising: an elongated tubular member (11) of a rigid material having a passage (12) extending longitudinally therethrough and sized for placement of said elongated tubular member over a cardiac electrical lead that is implanted in a vessel, a distal end (13) shaped for separation of encapsulating tissue from an implanted lead, and a relieved portion (14), whereby said relieved portion is flexible for laterally bending around vessel curves in which a cardiac electrical lead is implanted. ### Claim 2 (depends on 1) The dilator sheath of claim 1 wherein said relieved portion (14) includes a relief pattern (15) formed in said elongated tubular member. ### Claim 3 (depends on 2) The dilator sheath of claim 2 wherein said relief pattern includes a plurality of relief apertures (23) positioned in said elongated tubular member. ### Claim 4 (depends on 2) The dilator sheath of claim 2 wherein said relief pattern includes a plurality of main apertures (16), a plurality of distal apertures (17) proximate a distal end (18) of said relief pattern, and a plurality of proximal apertures (19) proximate a proximal end (20) of said relief pattern. ### Claim 5 (depends on 4) The dilator sheath of claim 4 wherein said distal and said proximal apertures have an aperture area (46) less than a main aperture area (47) of said main apertures. ### Claim 6 (depends on 2) The dilator sheath of claim 2 wherein said relief pattern includes pairs of diametrically opposed slots (24,25). ### Claim 7 (depends on 6) The dilator sheath of claim 6 wherein adjacent pairs (44, 45) of said pairs of diametrically opposed slots are circumferentially offset a prescribed angle (26,27). ### Claim 8 (depends on 6) The dilator sheath of claim 6 wherein slots in a pair (44) of said pairs of diametrically opposed slots are laterally separated from each other a prescribed distance (28). ### Claim 9 (depends on 6) The dilator sheath of claim 6 wherein adjacent pairs of said pairs of diametrically opposed slots are longitudinally spaced a prescribed distance (29) apart. ### Claim 10 (depends on 6) The dilator sheath of claim 6 wherein a first slot (24) in a pair (44) of said pairs of diametrically opposed slots extends into said tubular member a first depth (37). ### Claim 11 (depends on 10) The dilator sheath of claim 10 wherein a second slot (25) in said pair (44) of said pairs of diametrically opposed slots extends into said tubular member a second depth (38). ### Claim 12 (depends on 1) The dilator sheath of claim 1 wherein said relieved portion includes a plurality (30) of at least one of rectangular (31), round (32), square (33), elliptical (34), and teardrop-shaped (35) apertures or a combination (36) thereof. ### Claim 13 (depends on 1) The dilator sheath of claim 1 wherein said relieved portion includes a plurality of unopposed apertures (39) positioned in said relieved portion of said tubular member. ### Claim 14 (depends on 1) The dilator sheath of claim 1 further comprising a coating (40) extending over said relieved portion. ### Claim 15 (depends on 14) The dilator sheath of claim 14 wherein said coating includes a plastic tube (41). ### Claim 16 (depends on 15) The dilator sheath of claim 15 wherein said plastic tube comprises at least one from a group consisting of polytetrafluoroethylene, polyamides, and polyester. ### Claim 17 (depends on 1) The dilator sheath of claim 1 wherein said rigid material includes at least one from a group consisting of stainless steel, titanium, nitinol, nickel-based alloys, and a reinforced liquid crystal polymer. ### Claim 18 A locally flexible dilator sheath (10) comprising: an elongated tubular member (11) of a rigid material having a passage (12) extending longitudinally therethrough and sized for placement of said elongated tubular member over a cardiac electrical lead implanted in a vessel, a distal end (13) shaped for separation of encapsulating tissue from an implanted lead, and a relieved portion (14) having a relief pattern (15) formed therein; and a flexible plastic coating material (40) positioned over said relieved portion of said elongated tubular member, whereby said relieved portion is flexible for laterally bending around vessel curves in which a cardiac electrical lead is implanted. ### Claim 19 (depends on 18) The dilator sheath of claim 18 wherein said relief pattern includes pairs of diametrically opposed slots (24,25), adjacent pairs (44,45) of said pairs of said diametrically opposed slots being circumferentially offset a prescribed angle (26,27). ### Claim 20 A locally flexible dilator sheath (10) comprising: an elongated tubular member (11) of a rigid stainless steel material having a passage (12) extending longitudinally therethrough and sized for placement of said elongated tubular member over a cardiac electrical lead implanted in a vessel, a distal end (13) beveled and shaped for separation of encapsulating tissue from an implanted lead, and a relieved portion (14) having a relief pattern (15) of main pairs (16) of diametrically opposed slots (24,25) formed therein, adjacent pairs (44,45) of said diametrically opposed slots being longitudinally spaced a prescribed distance apart (29) and circumferentially offset a 90.degree. angle (26), slots of said pairs of diametrically opposed slots being laterally separated from each other a first separation distance (28), said relief pattern also having distal pairs (17) and proximal pairs (19) of diametrically opposed slots, each pair of slots being laterally separated from each other a second separation distance (22) greater than said first separation distance; a tube (41) of polyester material heat shrunk over said relieved portion including said relief pattern of said elongated tubular member; and a flange (42) positioned proximal said relieved portion on said elongated tubular member, whereby said relieved portion is flexible for laterally bending around vessel curves in which a cardiac electrical lead is implanted.