ISO 25539-2:2020

This document specifies requirements for the evaluation of stent systems (vascular stents and delivery systems) and requirements with respect to nomenclature, design attributes and information supplied by the manufacturer, based upon current medical knowledge. Guidance for the development of in vitro test methods is included in Annex D. This document is supplemental to ISO 14630, which specifies general requirements for the performance of non-active surgical implants. NOTE 1 Due to the variations in the design of implants covered by this document, and in some cases due to the emergence of novel types of such implants, acceptable standardized in vitro tests and clinical results are not always available. As further scientific and clinical data become available, appropriate revision of this document will be necessary. This document is applicable to vascular stents and vascular scaffolds (e.g. absorbable vascular scaffolds) used to treat vascular stenoses or other vascular abnormalities or pathologies. Some of the requirements are specific to endovascular treatment of arterial stenoses. Although uses of stent systems other than treatment of arterial stenoses (e.g. venous stenting) are within the scope of this document, comprehensive requirements and testing are not described for these uses. Similarly, specific stent configurations (e.g. bifurcation stents) are within the scope, but comprehensive requirements and testing are not described for these devices. Stents used in combination with an endovascular prosthesis to complete the treatment of a lesion, including bridging stents (e.g. stents placed in the renal arteries after deployment of a fenestrated endovascular prosthesis), are within the scope of this document, but test methods are not described for the combination. ISO 25539-1 also provides information relevant to the preclinical in vivo and clinical evaluations of such stents. Vascular stents that have surface modifications, such as drug and/or other coatings, are within the scope of this document. Stents covered with materials that significantly modify the permeability of the uncovered stent (e.g. by covering the stent-free-surface area) are within the scope of ISO 25539-1. The stent design or intended use might dictate the need to address functional requirements identified in both ISO 25539-1 and this document (e.g. stents used in combination with endovascular prostheses, stents used to treat aortic aneurysms). Balloons integral to the stent system are within the scope of this document. This document provides requirements beyond the requirements of ISO 10555-4, which are specific to the use of balloons with vascular stents. This document is not applicable to procedures and devices used prior to the introduction of the vascular stent, such as balloon angioplasty devices. Tacking devices intended to spot treat post-angioplasty dissections, coil supporting devices, and flow diverters are within the scope of this document, but comprehensive requirements and testing are not described for these devices. Although drug-eluting stents are within the scope of this document, this document is not comprehensive with respect to the drug-eluting properties of these devices. NOTE 2 Vascular device-drug combination products are within the scope of ISO 12417-1. Although absorbable stents and stents with absorbable coatings are within the scope of this document, this document is not comprehensive with respect to the absorbable properties of these devices. NOTE 3 Absorbable implants are within the scope of ISO/TS 17137. Although coated stents and coated stent systems are within the scope of this document, this document is not comprehensive with respect to coatings. NOTE 4 Some coating properties are within the scope of ISO 17327-1. This document does not address the requirements for, and the evaluation of, viable tissues and non-viable biologic materials used in the construction of vascular stents.