ISO 25539-4:2021
(Main)Cardiovascular implants — Endovascular devices — Part 4: Application of ISO 17327-1 for coated endovascular devices
Cardiovascular implants — Endovascular devices — Part 4: Application of ISO 17327-1 for coated endovascular devices
This document specifies the appropriate application of ISO 17327-1:2018 to coated endovascular prostheses, vascular stents, and vena cava filters. This document is intended to be used as a supplement to ISO 25539-1, ISO 25539-2, ISO 25539-3, ISO 12417-1 and ISO/TS 17137. The following coatings are within the scope of ISO 17327-1 and addressed in this document for endovascular devices: drug coatings (eluting and non-eluting), non-drug coatings (absorbable and non-absorbable), and chemistry-related surface modifications (oxide, such as TiO2, and non-oxide, such as amorphous silicon carbide and diamond-like carbon). This document is not applicable to coated delivery systems or coated ancillary devices (e.g. guidewires), as these coatings are not within the scope of ISO 17327-1, which is specifically directed to implant coatings. This document is not applicable to coverings of endovascular devices; however, if the covering of a device is coated, it is within the scope of this document. This document does not address the requirements for, and the evaluation of, viable tissues and non-viable biologic materials used as implant coatings.
Implants cardiovasculaires — Dispositifs endovasculaires — Partie 4: Application de l'ISO 17327-1 aux dispositifs endovasculaires munis d'un revêtement
General Information
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 25539-4
First edition
2021-11
Cardiovascular implants —
Endovascular devices —
Part 4:
Application of ISO 17327-1 for coated
endovascular devices
Reference number
ISO 25539-4:2021(E)
© ISO 2021
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ISO 25539-4:2021(E)
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ISO 25539-4:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements for coating properties . 2
4.1 General . 2
4.2 Vascular stents . 3
4.2.1 Drug coatings . 4
4.2.2 Non-drug coatings. 7
4.2.3 Chemistry-related surface modifications . 9
4.3 Endovascular prostheses . 10
4.4 Vena cava filters . 10
Bibliography .11
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ISO 25539-4:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 150, Implants for surgery, Subcommittee
SC 2, Cardiovascular implants and extracorporeal systems.
A list of all parts in the ISO 25539 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO 25539-4:2021(E)
Introduction
ISO 17327-1 has a broad scope, including all non-active surgical implants, and thus only some of the
requirements in ISO 17327-1 are applicable to coated endovascular devices. This document clarifies
how ISO 12417-1, ISO/TS 17137, ISO 25539-1, ISO 25539-2, and ISO 25539-3 satisfy the requirements
of ISO 17327-1. A device evaluation strategy is needed to identify the appropriate evaluation of specific
coated devices.
It is recognized by this ISO committee that many coated endovascular devices have been shown to be
safe and effective in clinical use. This document does not intend to require additional evaluation of these
devices to comply with this document as the testing does not provide useful information regarding
the expected clinical performance of the device. Manufacturers may rely on historical data gathered
under the guidance of ISO 25539-1, ISO 25539-2, and ISO 25539-3. Similarly, for device modifications or
changes in intended clinical use, this document does not intend to require additional evaluation of any
aspects of the device that are not expected to change the clinical performance.
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INTERNATIONAL STANDARD ISO 25539-4:2021(E)
Cardiovascular implants — Endovascular devices —
Part 4:
Application of ISO 17327-1 for coated endovascular devices
1 Scope
This document specifies the appropriate application of ISO 17327-1:2018 to coated endovascular
prostheses, vascular stents, and vena cava filters. This document is intended to be used as a supplement
to ISO 25539-1, ISO 25539-2, ISO 25539-3, ISO 12417-1 and ISO/TS 17137.
The following coatings are within the scope of ISO 17327-1 and addressed in this document for
endovascular devices: drug coatings (eluting and non-eluting), non-drug coatings (absorbable and non-
absorbable), and chemistry-related surface modifications (oxide, such as TiO , and non-oxide, such as
2
amorphous silicon carbide and diamond-like carbon).
This document is not applicable to coated delivery systems or coated ancillary devices (e.g. guidewires),
as these coatings are not within the scope of ISO 17327-1, which is specifically directed to implant
coatings.
This document is not applicable to coverings of endovascular devices; however, if the covering of a
device is coated, it is within the scope of this document.
This document does not address the requirements for, and the evaluation of, viable tissues and non-
viable biologic materials used as implant coatings.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 12417-1:2015, Cardiovascular implants and extracorporeal systems — Vascular device-drug
combination products — Part 1: General requirements
ISO/TS 17137:2021, Cardiovascular implants and extracorporeal systems — Cardiovascular absorbable
implants
ISO 17327-1:2018, Non-active surgical implants — Implant coating — Part 1: General requirements
ISO 25539-1:2017, Cardiovascular implants — Endovascular devices — Part 1: Endovascular prostheses
ISO 25539-2:2020, Cardiovascular implants — Endovascular devices — Part 2: Vascular stents
ISO 25539-3:2011, Cardiovascular implants — Endovascular devices — Part 3: Vena cava filters
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12417-1:2015, ISO/
TS 17137:2021, ISO 17327-1:2018, ISO 25539-1:2017, ISO 25539-2:2020, ISO 25539-3:2011 and the
following apply.
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ISO 25539-4:2021(E)
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
implant coating
surface coating or surface modification
Note 1 to entry: Implant coating is considered a constituent of an implant.
Note 2 to entry: A laminate, i.e. a composite material made of multiple layers of the same or different materials
with the same or different internal structures assembled sandwich-like and bonded by heat, pressure, welding,
soldering or adhesives, is not in itself considered an implant coating. But the exposed surface of the laminate can
be an implant coating.
Note 3 to entry: A covering, for example additional material (e.g. a graft) added to a structure (e.g. a stent)
specifically to bridge elements of the structure for the sole purpose of reducing the permeability of the structure,
is not considered an implant coating.
[SOURCE: ISO 17327-1:2018, 3.1]
4 Requirements for coating properties
4.1 General
Subclauses 4.2, 4.3, and 4.4 address the requirements as related to ISO 17327-1 for vascular stents,
endovascular prostheses and vena cava filters, respectively. The coating types identified in Table 1 are
addressed in this document. A device can have multiple coatings, each of which can be identified as
different or multiple coating sub-types. For example, a drug eluting stent with an absorbable matrix can
fit into eluting and absorbable coating sub-types.
Table 1 — Coating types addressed by this document
Coating category Coating sub-type I Coating sub-type II
Drug Eluting Non-eluting
Non-drug Absorbable Non-absorbable
Chemistry-related surface modifications Oxide Non-oxide
Evaluations identified in ISO 17327-1 will possibly not always be appropriate for all coated endovascular
prostheses, vascular stents and vena cava filters. The device evaluation strategy described in ISO 25539-
1 and ISO 25539-2 guides the development of the rationale for the testing selected to evaluate the
endovascular device based on the requirements of the device design and potential failure modes.
Evaluation of generic coating properties listed in ISO 17327-1 and identified as necessary by the device
evaluation strategy shall be completed. Evaluation of coating properties listed in ISO 17327-1 deemed
as not necessary by the device evaluation strategy do not need to be completed.
Due to the broad scope of ISO 17327-1, some terminology and associated requirements in that standard
are appropriate for other types of nonactive surgical implants, but inconsistent with standard
terminology and requirements for endovascular devices. In these cases, more relevant terminology
and requirements are presented in this document and correlated to the requirements in ISO 17327-
1. This includes the requirements for the consideration of adhesion strength and coating abrasion
resistance. For the coatings and implants addressed in this document, these generic coating properties
are evaluated by other tests. For example, adhesion strength is defined in ISO 17327-1:2018, as the
“load per unit area required to separate the coating from the substrate.” For the coatings and implants
addressed in this document, coating adhesion is considered part of the assessment of maintenance
of coating integrity which is evaluated through other means such as simulated use, durability, and
particulate generation. Thus, the specific characterization of the adhesion strength (i.e. load per unit
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ISO 25539-4:2021(E)
area required to separate the coating from the substrate) is not required. Similarly, coating abrasion
resistance is considered part of the assessment of maintenance of coating integrity.
For chemistry-related surface modifications on the devices within the scope of ISO 25539-1, ISO 25539-
2, and ISO 25539-3, coating coverage integrity evaluation is addressed through corrosion testing, while
corrosion resistance is not identified as a generic coating property in ISO 17327-1.
Evaluation of porosity and pore size, surface wettability, and surface texture are generally not
applicable to coatings on endovascular devices. The potential need to evaluate these properties can be
identified through the device evaluation strategy.
4.2 Vascular stents
In order to conform to the requirements of ISO 17327-1, the evaluation of drug coatings, non-drug
coatings, and chemistry-related surface modifications of stents shall be conducted for the properties as
outlined in Tables 3, 4, and 5, respectively. A description of column headings associated with Tables 3, 4,
and 5 is provided in Table 2. The available test methods (non-mandatory) that can be of use in meeting
the applicable requirements are provided in Tables 3, 4, and 5.
Table 2 — Description of Table 3, 4, and 5 column headings
Design attributes from Coating type
ISO 17327-1:2018 other ISO standards
Coating sub-type I Coating sub-type II
generic coating corresponding to ge-
property neric ISO 17327-1:2018 Applicable Applicable test Applicable Applicable
coating properties
requirement method requirement test method
The requirements identified
in the applicable ISO standard
that correspond to the generic The available test
coating property or design at- methods that can
Each generic coating tribute. Requirements that do be of use in meeting
Design attributes iden-
property from not align with the ISO 17327-1 the applicable
tified in the applicable
ISO 17327-1 to generic coating properties are requirement. These
ISO standards that corre- See column 3. See column 4.
be considered for not listed. Some requirements test methods are
spond to the ISO 17327-1
characterization or indicate the need to consider not mandatory and
generic coating property.
evaluation. the evaluation of a property, are not limited to
while others indicate that the ISO standardized
property shall be evaluated, methods.
as required by the applicable
standard.
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ISO 25539-4:2021(E)
4.2.1 Drug coatings
Table 3 — Applicable requirements and informative test methods related to drug coatings
Drug coating type
Design attributes from other ISO
ISO 17327-1:2018
standards correlated to generic Eluting Non-eluting
generic coating
ISO 17327-1:2018 coating prop-
property Applicable Applicable test Applicable Applicable test
erties
requirement method requirement method
ISO 25539-2:2020, 6.8 Drug-eluting
stent
— Ability of the stent to consist-
ently contain the desired type and
amount of drug
— Conformance of the residual drug
quantity to design specifications for
drug-eluting stents and not for drug
containing stents
ISO 25539-2:2020, ISO 25539-2:2020,
— Freedom of the drug(s) from
8.1 Design evalua- 8.1 Design evalua-
deleterious impurity and degradant
tion – General tion – General
levels at manufacture and with
storage
ISO 12417-1:2015, ISO 12417-1:2015,
7.2.4.3.4 Drug 7.2.4.3.4 Drug
ISO 12417-1:2015, 5.2.2, d) Matrix
Use applicable Use applicable
content content
Chemic
...
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