Stent Recoil, Foreshortening, Compression: Measured parameters
- Stent recoil: Percentage by which the diameter of a stent decreases from its expanded diameter (when the balloon is inflated at the nominal pressure) to its relaxed diameter (when the balloon is retrieved from the stent).
- Stent foreshortening: Percentage by which the length of a stent decreases from its crimped state to its deployed state (when the balloon is retrieved from the stent).
- Stent Longitudinal Compression: Percentage by which the length of a deployed stent decreases when recrossed by a catheter.
Stent Recoil, Foreshortening, Compression: Scope
- Balloon Expandable Stents
- SS, CrCo Stent
Stent Recoil, Foreshortening, Compression: Applicable standards
- ISO 25539-2 - CARDIOVASCULAR IMPLANTS - ENDOVASCULAR DEVICES - PART 2: VASCULAR STENTS
- FDA GUIDELINES - GUIDANCE FOR INDUSTRY AND FDA STAFF NON-CLINICAL ENGINEERING TESTS AND RECOMMENDED LABELING FOR INTRAVASCULAR STENTS AND ASSOCIATED DELIVERY SYSTEMS
- GLP STUDIES PER CODE OF FEDERAL REGULATIONS CFR21, PART 58 - GOOD LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES (APRIL 2010)
- ASTM F2079-09 STANDARD TEST METHOD FOR MEASURING INTRINSIC ELASTIC RECOIL OF BALLOON-EXPANDABLE STENTS
- ASTM F2081-06 STANDARD GUIDE FOR CHARACTERIZATION AND PRESENTATION OF THE DIMENSIONAL ATTRIBUTES OF VASCULAR STENTS
Stent Recoil, Foreshortening, Compression: Associated tests
- Dimensional attributes - Cardiovascular implants characterization
- Stent radial force measurement
- Accelerated Fatigue
- Device Radiopacity
Stent Recoil: Test method description
A contactless optical gauging machine (Smartscope, OGP) is used (highest magnification: x145) to measure the undeployed stent length. It is then used to measure diameter at different sections and at 2 planes (perpendicular direction one from each other), both when the balloon is inflated at a specified pressure and per IFU and when the balloon is deflated. Finally the length of the expanded stent is measured. The stent recoil for each location and the stent foreshortening are then calculated. Specified balloon pressure is held 30 seconds in order to allow the balloon and/or stent to stabilize. The stent is free from external stress.
Stent Longitudinal Compression test method in anatomical models using the IDTE 2000
Stent Longitudinal Compression:
Stent longitudinal compression in good apposition and in mal apposition models can be assessed in during simulated using the IDTE 2000 from Machine Solutions. Details of the new test method can be found in a comparative longitudinal study presented at EBR 2012 in Marseille, FRANCE and at the Paris Cardiovascular Interventions Course 2012. For more information on our test method Please follow this link for more information