Method of loading expandable medical device in a low vapor environment

• US 20060196073A1
• Filed: 02/10/2006
• Published: 09/07/2006
• Est. Priority Date: 02/11/2005
• Status: Active Grant

• Current Assignee: Cook Medical Incorporated (Cook Group Incorporated)
• Original Assignee: Cook Incorporated (Cook Group Incorporated)
• Inventors: Parker, Fred T.
• Granted Patent: US 7,459,042 B2
• Time in Patent Office: Days
• US Class Current: 34/62
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument

Abstract

A method (112) of loading an expandable medical device in a low vapor environment. The method includes placing the device in a loading chamber (114) at, for example, room temperature and removing (116) from the chamber any undesirable contaminants such as water vapor that can form condensation on the device when the device is cooled for compression into a transfer tube or delivery catheter. The temperature in the chamber is lowered (118) to a temperature below the transition temperature (martensitic finish) of the device. The device is compressed (120) below its'"'"' transition temperature and loaded (122) into a delivery or transfer device.

Claims

1. A method of loading an expandable medical device in a low vapor environment, comprising the steps of:

placing an expandable medical device in a chamber at a first temperature,

removing from the chamber at least one of a vapor and any other impurities that can form at least one of a liquid and a solid on the medical device at a second temperature lower than the first temperature,

lowering the temperature in the chamber to a temperature below at least one of the second temperature and a transition temperature of the medical device,

compressing the medical device at a temperature below a transition temperature of the medical device, and

loading the compressed medical device into at least one of a delivery device and a transfer device.

2. The method of claim 1, wherein the step of removing at least one of the vapor and any other impurities includes the step of purging the chamber with a gas for at least a prescribed period of time.

3. The method of claim 1, wherein the step of lowering the temperature in the chamber includes the step of lowering the temperature at a rate slow enough to remove the at least one of the vapor and any other impurities before condensation or sublimation thereof.

4. The method of claim 1, wherein the step of lowering the temperature in the chamber includes introducing liquid nitrogen into the chamber, heating the liquid nitrogen to produce nitrogen gas, and lowering the temperature in the chamber with the nitrogen gas.

5. The method of claim 1, further comprising the step of inserting the medical deice in a compression fixture.

6. The method of claim 5, wherein the step of compressing includes the steps of inserting the medical device at a temperature below the transition temperature of the device into the compression fixture and compressing the medical device with a first diameter to a second diameter less than the first diameter.

7. The method of claim 1, wherein the step of removing at least one of the vapor and any other impurities includes the step of purging the chamber with a gas for at least a prescribed period of time and wherein the step of lowering the temperature in the chamber includes the step of lowering the temperature at a rate slow enough to remove the at least one of the vapor and any other impurities before condensation or sublimitation thereof.

8. The method of claim 7, wherein the step of lowering the temperature in the chamber further includes the steps of introducing liquid nitrogen into the chamber, heating the liquid nitrogen to produce nitrogen gas, and lowering the temperature in the chamber with the nitrogen gas.

9. The method of claim 8, further comprising the step of inserting the medical deice in a compression fixture.

10. The method of claim 9, wherein the step of compressing includes the steps of inserting the medical device at a temperature below the transition temperature of the device into the compression fixture and compressing the medical device with a first diameter to a second diameter less than the first diameter.