# US 10,307,277 B2 · Method of uniform crimping and expansion of medical devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,277 B2 - Document ID: US10307277B2 - Status: Granted - Kind: B2 - Application number: 15/627,337 - Filed: 2017-06-19 - Published: 2017-12-07 - Granted: 2019-06-04 - Earliest claimed: 2012-10-04 - Assignees: Abbott Cardiovascular Systems Inc. - Applicants: Abbott Cardiovascular Systems Inc. - Inventors: Yunbing Wang - Web page: https://patentgrep.com/patent/US10307277B2 ## CPC - A61F 2/958: Inflatable balloons for placing stents or stent-grafts - A61F 2/91: made from perforated sheets or tubes, e.g. perforated by laser cuts or etched holes - A61F 2/9522: {Means for mounting a stent or stent-graft onto or into a placement instrument} - A61F 2002/9583: {Means for holding the stent on the balloon, e.g. using protrusions, adhesives or an outer sleeve} - A61M 25/1025: {Connections between catheter tubes and inflation tubes} - B23P 11/00: Connecting or disconnecting metal parts or objects by metal-working techniques not otherwise provided for (connecting sheet metal or metal tubes, rods or profiles B21D39/00; riveting B21J; soldering, unsoldering, welding B23K; hand tools for connecting wire or strip B25B25/00; connecting metal parts by adhesives F16B11/00) - Y10T 29/49863: with prestressing of part - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - 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)} - B23P: METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS (arrangements for copying or controlling B23Q) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A medical device-includes a scaffold crimped to a catheter having an expansion balloon. The scaffold is crimped to the balloon by a process that includes one or more balloon pressurization steps. The balloon pressurization steps are selected to enhance scaffold retention to the balloon, maintain a relatively uniform arrangement of balloon folds about the inner surface of the crimped scaffold so that the scaffold expands in a uniform manner when the balloon is inflated, and to avoid any possible over-stretching of balloon material. ## Claims ### Claim 1 A method, comprising the steps of: providing a first balloon and a second balloon, wherein a nominal inflation diameter of the first balloon is greater than a nominal inflation diameter of the second balloon; and crimping a stent or scaffold to the second balloon, the stent or scaffold having an outer diameter, wherein prior to the crimping the outer diameter is equal to a pre-crimp diameter, wherein the crimping to the second balloon comprises the following steps: performing a first crimping of the stent or scaffold while the stent or scaffold is supported by the first balloon, the first crimping including reducing the outer diameter from the pre-crimp diameter to a first diameter, replacing the first balloon with the second balloon, inflating the second balloon, and after the first crimping, performing a second crimping wherein the stent or scaffold is crimped to the second balloon, the second crimping comprising: while the second balloon is inflated, performing crimping steps (a), (b), (c) and (d): (a) reducing the outer diameter to a second diameter, (b) maintaining the second diameter for a first dwell period, (c) reducing the outer diameter to a third diameter that is less than the second diameter, and (d) maintaining the third diameter for a second dwell period. ### Claim 2 (depends on 1) The method of claim 1, wherein the third diameter is between 40% to 60% of the pre-crimp diameter. ### Claim 3 (depends on 1) The method of claim 1, wherein the scaffold comprises a polymer having a lower end of a glass transition temperature (TG) and during the first and second crimping the scaffold temperature is between TG and 15 degrees less than TG. ### Claim 4 (depends on 3) The method of claim 3, wherein the scaffold comprises poly (L-lactide) (PLLA) and during the first and second crimping the scaffold temperature is between 40 Deg. C. and 55 Deg. C. ### Claim 5 (depends on 2) The method of claim 2, wherein while the stent or scaffold has the third diameter, a pressure in the inflated second balloon is decreased from a first pressure to a second pressure and the second pressure is maintained during the second dwell period. ### Claim 6 (depends on 2) The method of claim 2, wherein while the outer diameter has the third diameter the second balloon is deflated by opening a valve supplying a pressure to the balloon, and wherein the second crimping further comprises the step of reducing the outer diameter to a fourth diameter. ### Claim 7 (depends on 1) The method of claim 1, wherein the second balloon is inflated for each of the crimping steps (a), (b), (c) and (d). ### Claim 8 (depends on 7) The method of claim 7, wherein the second balloon has an inflation pressure and the inflation pressure is the same for the crimping steps (a) and (c). ### Claim 9 (depends on 1) The method of claim 1, wherein the outer diameter is greater than the first diameter after replacing the first balloon with the second balloon, and the second diameter is the same as the first diameter. ### Claim 10 (depends on 1) The method of claim 1, wherein the third diameter is about 60% of the first diameter. ### Claim 11 (depends on 1) The method of claim 1, wherein the first balloon has an overinflated state during the first crimping step. ### Claim 12 (depends on 1) The method of claim 1, wherein the second balloon has an overinflated state during the second crimping step. ### Claim 13 (depends on 12) The method of claim 12, wherein the second balloon has an overinflated state during at least steps (a) and (b). ### Claim 14 (depends on 1) The method of claim 1, wherein the second balloon is a pleated balloon and prior to the second crimping all pleats in the balloon are substantially removed. ### Claim 15 A method comprising the steps of: crimping a stent or scaffold to a balloon of a balloon catheter, the stent or scaffold having an outer diameter, wherein prior to the crimping the outer diameter is equal to a pre-crimp diameter of the stent or scaffold, the crimping comprising the following steps: performing a first crimping to reduce the outer diameter from the pre-crimp diameter to a first diameter while supporting the stent or scaffold on an inflated first balloon having a nominal inflation diameter greater than a nominal inflation diameter of the catheter balloon; replacing the first balloon with the catheter balloon; inflating the catheter balloon; and performing a second crimping of the stent or scaffold to the catheter balloon, comprising: while the catheter balloon is inflated and supporting the stent or scaffold, performing steps (a), (b), (c) and (d): (a) reducing the outer diameter to a second diameter, (b) maintaining the second diameter for a first dwell period, (c) reducing the outer diameter to a third diameter that is less than the second diameter, and (d) maintaining the third diameter for a second dwell period. ### Claim 16 (depends on 15) The method of claim 15, wherein the first balloon has a higher burst pressure than the catheter balloon. ### Claim 17 (depends on 15) The method of claim 15, wherein an inner diameter of the stent or scaffold before the second crimping is larger than a fully inflated or over inflated diameter of the catheter balloon and equal to or less than a fully inflated or over inflated diameter of the first balloon. ### Claim 18 (depends on 15) The method of claim 15, wherein the catheter balloon is inflated for each of the steps (a), (b), (c) and (d). ### Claim 19 (depends on 15) The method of claim 15, wherein the catheter balloon is overinflated during the steps (a) and (c).