AAMI ISO TIR17137:2014 pdf download – Cardiovascular implants and extracorporeal systems – Cardiovascular absorbable implants
1 Scope
This Technical Specification outlines design verification and validation considerations for absorbable cardiovascular implants. NOTE Due to the variations in the design of implants covered by this Technical Specification and in some cases due to the relatively recent development of some of these implants (e.g. absorbable stents), acceptable standardized in vitro tests and clinical results are not always available. As further scientific and clinical data become available, appropriate revision of this Technical Specification will be necessary. For the purpose of this Technical Specification the terms “vessel and/or vascular space” refer to the entire circulatory system, including the heart and all vasculature. This Technical Specification is applicable to implants in direct contact with the cardiovascular system, where the intended action is upon the circulatory system. This technical specification does not address the specific evaluation of issues associated with viable tissues, viable cells, and/or implants with non-viable biological materials and their derivatives. Additionally, procedures and devices used prior to and following the introduction of the absorbable cardiovascular implant (e.g. balloon angioplasty devices) are excluded from the scope of this Technical Specification if they do not affect the absorption aspects of the implant. A cardiovascular absorbable implant may incorporate substance(s) which, if used separately, can be considered to be a medicinal product (drug product) but the action of the medicinal substance is ancillary to that of the implant and supports the primary mode of action of the implant. NOTE Some aspects of absorbable components of cardiovascular device-drug combination products (e.g. coatings) in their connection with drug-related aspects of the device are addressed in ISO/TS 12417.
4.4 Materials
The requirements of ISO 1 4630:2012, Clause 6, shall apply. Additional testing appropriate to specific material types (e.g. metals, polymers, drugs) shall be performed to determine material acceptability for use in the design. For example, a general guide for assessing absorbable polymeric implants can be found in ASTM F2902. In a more specific example, absorbable materials dependent on shape memory properties should be subjected to testing that assesses transformation properties. For drug-eluting absorbable implants, drug identity testing shall be performed, including the identification of impurities and degradants. Electro-chemical potentials of differing metals (stents, guidewires, other accessory devices) might require additional types of testing.
4.5.1.2 Considerations for absorbable product
For absorbable products, non-standard packaging attributes may be needed to mitigate or eliminate the effects of environmental factors in order to maintain the physical, chemical and/or mechanical specifications of the implant. Where the absorbable product is susceptible to hydrolytic or corrosive degradation, consideration should be given toward the control and/or removal of moisture from the package interior (e.g. through the use of moisture resistant packaging materials and/or desiccants). In addition, absorbable products may also be susceptible to physical, chemical, and/or mechanical degradation under extreme temperature conditions. For example, storage at temperatures that approach or exceed the glass transition temperature of absorbable polymeric products might adversely affect the physical and chemical state of the implant. Therefore, storage conditions should be specified that limit the temperature range and time limit of implant exposure.