# US 7,743,481 B2 · Stent crimping

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 7,743,481 B2
- Document ID: US7743481B2
- Status: Granted
- Kind: B2
- Application number: 10/541,421
- Filed: 2005-06-02
- Published: 2008-02-07
- Granted: 2010-06-29
- Earliest claimed: 2005-04-29
- Assignees: Arterial Remodelling Technologies, Inc.
- Inventors: Antoine Lafont; Serge Piranda; Patrick Sabaria; Tahmer Sharkawi; Michel Vert
- Web page: https://patentgrep.com/patent/US7743481B2

## CPC

- A61F 2/95: Instruments specially adapted for placement or removal of stents or stent-grafts
- A61F 2/9522: {Means for mounting a stent or stent-graft onto or into a placement instrument}
- Y10T 29/49927: Hollow body is axially joined cup or tube
- Y10T 29/53657: to apply or remove a resilient article [e.g., tube, sleeve, etc.]
- 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)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Methods of crimping polymeric stents that simultaneously apply a radial force to the stent to reduce the diameter of the stent and a longitudinal force to elongate of the stent. According to one such method, a stent is inserted into an elastic tube having an inner surface that defines a passage. The tube is pulled to cause stretching of the tube. When the tube is stretched, the inner surface of the tube engages an outer surface of the stent and applies simultaneous longitudinal and radial forces to the outer surface of the stent. The simultaneously applied longitudinal and radial forces simultaneously reduce a radial extent of the stent and increase a longitudinal extent of the stent.

## Claims

### Claim 1

A method of crimping a polymeric stent, comprising:
a) inserting the stent into an elastic tube having an inner surface that defines a passage;
b) pulling the tube to cause stretching of the tube, such that the inner surface of the tube engages an outer surface of the stent and applies simultaneous longitudinal and radial forces to the outer surface of the stent to thereby simultaneously reduce a radial extent of the stent and increase a longitudinal extent of the stent; and
c) releasing the tube to allow the tube to return to an undeformed size.

### Claim 2 (depends on 1)

The method of claim 1 wherein the first and second end portions are pulled in opposite directions to impart simultaneous compressing and elongating forces to the outer surface of the stent.

### Claim 3 (depends on 1)

The method of claim 1 further comprising removing a crimped stent from the tube.

### Claim 4 (depends on 1)

The method of claim 1 wherein the tube is an elastic silicone tube.

### Claim 5 (depends on 1)

The method of claim 1 further comprising imparting a predetermined final size and shape to the stent before crimping the stent.

### Claim 6 (depends on 5)

The method of claim 5 further comprising cooling the stent, releasing the tube to allow the tube to return to its original shape, and removing the crimped stent from the tube.

### Claim 7 (depends on 1)

The method of claim 1 further comprising heating the stent around the glass transition temperature of the stent before crimping the stent.

### Claim 8 (depends on 1)

The method of claim 1 wherein the elastic tube is made from an elastomeric polymer and wherein a diameter of the tube is reduced upon stretching of the tube.

### Claim 9 (depends on 1)

The method of claim 1 further comprising inserting a diameter setting member into the stent before crimping the stent to define a diameter of the crimped stent.

### Claim 10 (depends on 1)

The method of claim 1 wherein an inner surface of the tube adheres to an outer surface of the stent to apply simultaneous longitudinal and radial forces to the stent.

### Claim 11 (depends on 1)

The method of claim 1 wherein the stent is crimped to an angioplasty balloon by pulling the tube.

### Claim 12 (depends on 1)

The method of claim 1 further comprising removing the stent from the tube and crimping the stent to an angioplasty balloon with a second crimping device.

### Claim 13 (depends on 1)

The method of claim 1 wherein a solvent is added to the tube to expand the tube before the stent is placed in the tube and evaporating the solvent to bring the tube into contact with the stent.

### Claim 14

An apparatus for crimping a polymeric stent having an outer surface, comprising:
a) an elastic tube having an inner surface that defines a passage that is sized to fit over the outer surface of the stent;
b) an actuator coupled to the elastic tube, wherein movement of the actuator increases a length of the elastic tube and decreases an extent of the passage, wherein the inner surface of the tube engages the outer surface of the stent and reduces an extent of the stent to thereby crimp the stent; and
c) a heating element for heating the stent around the glass transition temperature of the stent before crimping the stent.

### Claim 15 (depends on 14)

The apparatus of claim 14 wherein the increase in length of the elastic tube and the decrease in extent of the passage of the tube reduces a diametric extent of the stent and increases a longitudinal extent of the stent.

### Claim 16 (depends on 14)

The apparatus of claim 14 wherein the actuator pulls first and second end portions of the elastic tube in opposite directions to impart simultaneous compressing and elongating forces to the outer surface of the stent.

### Claim 17 (depends on 14)

The apparatus of claim 14 wherein the tube is an elastic silicone tube.

### Claim 18 (depends on 14)

The apparatus of claim 14 further comprising a diameter setting member that is inserted into the stent before crimping the stent to define a diameter of the crimped stent.

### Claim 19

A method of preparing a polymeric stent for application in vasculature of a patient, comprising:
a) imparting predetermined final size and shape to the stent by heating the stent to a temperature above the glass transition temperature of the stent such that the predetermined size and shape is retained and then cooling the stent;
b) inserting the stent into an elastic tube having an inner surface that defines a passage;
c) heating the stent to a temperature at or above a glass transition temperature such that the imparted final size and shape is retained by the stent;
d) pulling the tube to cause stretching of the tube, such that the inner surface of the tube engages an outer surface of the stent and applies simultaneous longitudinal and radial forces to the outer surface of the stent to thereby simultaneously reduce a radial extent of the stent and increase a longitudinal extent of the stent;
e) cooling the stent to a temperature below the glass transition temperature;
f) releasing the tube, such that at least a portion of the inner surface of the tube disengages at least a portion of the outer surface of the stent; and
g) removing the stent from the tube.