SIST EN 1064:2020

SLOVENSKI STANDARD
oSIST prEN 1064:2019
01-maj-2019
=GUDYVWYHQDLQIRUPDWLND6WDQGDUGQLNRPXQLNDFLMVNLSURWRNRO5DþXQDOQLãNR
SRGSUWDHOHNWURNDUGLRJUDILMD
Health informatics - Standard communication protocol - Computer-assisted
electrocardiography
Medizinische Informatik - Standardkommunikationsprotokoll - Computergestützte
Elektrokardiographie; Englische Fassung EN 1064:2005+A1:2007
Informatique de Santé - Protocole de Communication Standard pour
L'Electrocardiographie Assistée par Ordinateur
Ta slovenski standard je istoveten z: prEN 1064
ICS:
35.240.80 Uporabniške rešitve IT v IT applications in health care
zdravstveni tehniki technology
oSIST prEN 1064:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 1064:2019

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oSIST prEN 1064:2019


DRAFT
EUROPEAN STANDARD
prEN 1064
NORME EUROPÉENNE

EUROPÄISCHE NORM

March 2019
ICS 35.240.80 Will supersede EN 1064:2005+A1:2007
English Version

Health informatics - Standard communication protocol -
Computer-assisted electrocardiography
Informatique de Santé - Protocole de Communication Medizinische Informatik -
Standard pour L'Electrocardiographie Assistée par Standardkommunikationsprotokoll -
Ordinateur Computergestützte Elektrokardiographie; Englische
Fassung EN 1064:2005+A1:2007
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 251.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1064:2019 E
worldwide for CEN national Members.

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Contents Page
Introduction . 3
1 Scope . 5
2 Normative references . 6
3 Terms and definitions . 6
4 Symbols and abbreviated terms . 8
5 Definition of the data contents and format . 9
5.1 General considerations . 9
5.2 Specifications for the data structure . 10
5.3 Pointer section – Section 0 . 15
5.4 Header information - Patient data / ECG metadata – Section 1 . 16
5.5 Huffman tables – Section 2 . 33
5.6 ECG leads definition – Section 3 . 35
5.7 Reserved for legacy SCP-ECG versions – Section 4 . 44
5.8 Encoded type 0 reference beat data – Section 5 . 46
5.9 Short-term ECG Rhythm data – Section 6. 49
5.10 Global ECG measurements – Section 7 . 51
5.11 Storage of full text interpretive statements – Section 8 . 64
5.12 Storage of manufacturer specific interpretive statements and data related to the
overreading trail – Section 9 . 66
5.13 Per-lead ECG measurements – Section 10 . 66
5.14 Storage of the universal ECG interpretive statement codes – Section 11 . 75
5.15 Long-term ECG rhythm data – Section 12 . 79
5.16 Stress tests, Drug trials and Protocol based ECG recordings Metadata – Section 13 . 84
5.17 Selected ECG Sequences Repository – Section 14 . 95
5.18 Beat-by-Beat ECG measurements and annotations – Section 15 . 99
5.19 Selected ECG beats measurements and annotations – Section 16 . 114
5.20 Pacemaker Spikes measurements and annotations – Section 17 . 123
5.21 Additional ECG annotations – Section 18 . 137
Annex A (normative) Supplementary information and additional encoding specifications . 144
Annex B (informative)  Universal ECG interpretation statements codes . 152
Annex C (informative) Definition of compliance with the SCP ECG standard . 178
Annex D (Informative) Methodology of the recommended ECG signal compression technique . 187
Annex E (informative) Cross-references to other ECG standards . 223
Annex F (informative) Implementation Recommendations . 226
Annex G (informative) Glossary . 228
Bibliography . 230

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Introduction
The electrocardiogram (ECG) is a recording of voltage changes transmitted to the body surface by
electrical events in the heart muscle, providing direct evidence of cardiac rhythm and conduction, and
indirect evidence of certain aspects of myocardial anatomy, blood supply and function. During its
propagation to the surface, extracardiac tissues may intervene and influence the ECG morphology.
Electrocardiography has been used for many years, and is increasingly used as a key, non-invasive and
low cost method in the diagnosis and early detection of coronary heart disease, which is the leading cause
1
of mortality worldwide [56] . Of the 57 million global deaths in 2008, 36 million (63 %) were due to non-
communicable diseases (NCDs) and 17.3 million (30 %) were due to cardiovascular diseases (CVDs). Out
of these 17.3 million cardiovascular deaths, heart attacks were responsible for 7.3 million and strokes
were responsible for 6.2 million deaths. More than 3 million of these 17.3 million CVD deaths occurred
before the age of 60. The percentage of premature deaths from CVDs ranges from 4 % in high-income
countries to 42 % in low-income countries [56].
In 2008, it was estimated that more than 300 million standard 12 lead ECGs are recorded yearly in the
US for routine diagnostic and screening purposes [37]. The Mayo Clinic, for example, nowadays performs
about 240,000 standard ECG recordings per year [58].
According to Transparency Market Research, the overall shipment of ECG monitoring systems including
resting ECG recorders, ECG stress testing systems, Event recorders and Holter monitors, will rise from
262.1 thousand units in 2011 to 374.8 thousand units in 2016, with a 2016 market size estimation of
US$822.1 million [59]. Marketsandmarkets.com on its side estimates that the global Diagnostic ECG
Market will reach $5,435 million by 2020 [57]. The factors driving this market include the increasing
geriatric population, rising incidences of lifestyle diseases, technological advancements in diagnostic ECG
devices, and high growth rate in developing countries.
Almost all newer electrocardiographs nowadays use digital recording, interpretation and communication
techniques, and there is an increasing number of portable and even wearable (mobile) ECG devices that
are now used instead of the traditional ECG cart. These stand-alone, microprocessor based machines and
devices can be connected to each other, to a host computer, to the internet or to a hospital information
system for reporting, long-term storage in the Medical Electronic Record and serial comparison. To this
end, various manufacturers have used different techniques.
It is in the general public interest for users not to be restricted in their options by incompatible technical
features and services of different systems and devices. ECG processing is increasingly being integrated
with various other types of data processing in health care. This evolution will have considerable impact
on the storage and communication of ECG data. There are many different end-users who for different
purposes (support of patient care, management, drug trials and/or drug management, research and
education) want to obtain a copy of the signal data, of the interpretive report and/or measurement
results. Being one of the very first ever developed systems for medical decision support, computerized
ECG interpretation stretches from departments of cardiology in hospitals, to general practitioners in
primary care and health care centres and to home care. In life-threatening acute myocardial infarction,
ECGs are now used in ambulances by paramedical personnel to assess the necessity for administering
thrombolytic agents or to alert cathlabs to prepare for a coronary intervention, with long-distance
monitoring whenever possible, and in self-care situations to detect ischemia or life threatening
arrhythmias as early as possible [31].
To facilitate the exchange of information between various systems, it was of utmost importance that a
standard communications protocol for computer-aided electrocardiography (SCP-ECG) was established,
as defined in this document. Its aim is to specify a data format for transferring ECG signals, metadata and

1
Figures in square brackets refer to the Bibliography.
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reports from any vendor's computerized ECG device to any other's vendor central ECG management
system. The same standard should also allow standardized transfer of digitised ECG data and results
between various computer and information systems, Electronic Medical Records, and ECG data
repositories.
Under this standard communications protocol (SCP-ECG), the contents and format of the ECG waveform
data, metadata and the measurements from ECG devices of different manufacturers are not expected to
be identical. As a result, the determination of the suitability of a device and/or system for any particular
application remains with the user/purchaser. The following possible uses of ECG records require special
attention:
— serial comparison of ECGs and interpretations;
— printout formats of ECGs;
— maintaining an audit trail of edits and annotations;
— integration into an electronic medical record;
— integration into clinical information systems and data repositories.
The users are cautioned to make sure that the data contents and format of the waveform data, metadata,
measurements, and the interpretive statements meet their specific needs. If more than one type of ECG
device and/or ECG management system is interconnected, the user is also advised to verify with the
manufacturers that the data from different systems and devices are compatible with each other and with
the user’s needs.
In order to understand this document, the reader needs some basic knowledge of electrocardiology,
electrocardiography and signal processing.
This document not only relates to the conventional recording of the electrocardiogram, i.e. the so-called
standard 12-lead electrocardiogram and the vectorcardiogram (VCG), but also to other types of ECG such
as Holter ECG, physiologic monitoring ECG, stress ECG, intracardiac ECG, home care ECG monitoring and
wearable self-care ECG devices. Initially, the electric connections used for recording the ECG were made
to the limbs only. These connections to the right arm (RA), left arm (LA) and left leg (LL) were introduced
by Einthoven. The electrical variations detected by these electrode connections are algebraically
combined to form the bipolar leads I, II, and III. Lead I, for example records the difference between the
voltages of the electrodes placed on the left arm and the right arm. The unipolar electrocardiographic
leads (VR, VL, VF and the precordial leads V1 to V6) were introduced much later, starting in 1933. In these
leads, potentials are recorded at one location with respect to a level which does not vary significantly in
electrical activity during cardiac contraction. The “augmented” limb lead potentials (aVR, aVL, aVF) are
recorded with reference to the average potential of (L+F), (R+F) and (L+R) respectively, where R, L and
F refer to the RA, LA and LL electrodes. The unipolar chest leads are recorded with reference to the
average potential of (RA+RL+LL)/3 which is called the Wilson “central terminal” (CT). In
vectorcardiography recordings are made from three mutually orthogonal leads, running parallel to one
of the rectilinear coordinate axes of the body. The axes are the X-axis going right to left, the Y-axis with a
top to bottom orientation, and the Z or front to back axis. In 12-Lead stress ECG recordings, the limb
electrodes are placed on the torso to reduce limb movement artefacts. The same electrode positions apply
to some Holter, emergency and home care recordings, both to limit movement artefacts and undressing.
In some research centres, so-called body surface maps are obtained by placing many (from 24 to 124 or
even more) closely spaced electrodes around the torso. This document has not been designed to handle
exchange of such recordings, although future extensions could be made to this end. The standard has also
not been designed to exchange specialized recordings of intracardiac potentials (electrograms) recorded
in the EP (Electrophysiology) laboratories or by cardiac implantable electronic devices (CIED), viz
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pacemakers, implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT)
devices, although it could also be used to this intent.
ECG computer processing can be reduced to 3 principal stages:
1) data acquisition, encoding, transmission and storage;
2) pattern recognition and feature extraction, i.e. ECG measurement;
3) diagnostic classification.
In each of these stages there are important needs for standardization and quality assurance testing. The
scope of this document is confined to the first of these three stages. Quality assurance of ECG
measurement and diagnostic classification have been addressed by the CSE Working Party and to some
extent by IEC 60601-2-25:2011 [4]. The latter also addresses the issue of quality assurance testing of the
signal acquisition hardware and filtering.
The various data sections that shall be transmitted by means of the standard ECG communications
protocol are defined in Clause 5 of this document.
The selection and definition of ECG specific high-level syntaxes and query languages for transfer of
messages and data between devices or between devices and hosts or host-to-hosts, using for example
Bluetooth, TCP/IP, FTP, USB, Filesystem, HL7, etc., are beyond the scope of this document.
The main goal of the SCP-ECG standard is to address ECG data and related metadata structuring,
semantics and syntax, with the objective of facilitating interoperability and thus to support and promote
the exchange of the relevant information for ECG diagnosis. Indeed, as recommended by the
ACC/AHA/ACP-ASIM task force: “Electrocardiogram readers should understand the importance of
comparing a current tracing to previous tracings in order to make correct diagnoses. All abnormal
tracings should be compared with available previous tracings. The accuracy of some diagnoses may be
considerably enhanced by reviewing previous tracings.” [33]. It is thus of utmost importance to provide
a storage format enabling any device or computer program performing the analysis and interpretation of
a current ECG to perform a reliable re-analysis of the previous ECGs. For assessing serial changes between
ECG measurements it is necessary that the measurements are computed in the same way on each
recording in order to avoid any bias.
The binary encoding of ECG data within SCP-ECG and the included content self-control capabilities allow
for an efficient encoding, an encapsulation of all ECG-related parameters, and a small memory footprint
compliant with mHealth scenarios for an early detection of cardiac diseases, anywhere and anytime [31],
[40]. These features not only provide an advantage in data transmission and archiving, but also when the
data need to be encrypted (for protecting the data and the confidentiality), or signed (protection against
changes).
1 Scope
This document specifies the common conventions required for the interchange of specific patient data
(demographic, recording conditions .), ECG signal data and metadata, ECG measurements and ECG
annotations, and ECG interpretation results.
This document specifies the content and structure of the information which is to be interchanged
between digital ECG electrocardiographs/devices and computer ECG management systems, as well as
other computer or information systems (cloud, etc.) where ECG data can be stored.
This document defines the way to describe and encode standard and medium to long-term
electrocardiogram waveforms measured in physiological laboratories, hospital wards, clinics and
primary care medical check-ups, ambulatory and home care. It covers electrocardiograms such as 12-
lead, 15-lead, 18-lead, Cabrera lead, Nehb lead, Frank lead, XYZ lead, Holter ECGs and exercise ECGs that
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are recorded, measured and analysed by equipment such as electrocardiographs, patient monitors,
wearable devices. It also covers intracardiac electrograms recorded by implantable devices as well as the
analysis results of ECG analysis and interpretation systems and software that are compatible with SCP-
ECG.
ECG waveforms and data that are not in the scope of this technical specification include real-time ECG
waveform encoding and analysis used for physiological monitors, and intra-cardiac or extra cardiac ECG
mapping.
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/IEC 10646, Information technology — Universal Coded Character Set (UCS)
2
ISO/IEEE 11073-10101:2004, Health informatics — Point-of-care medical device communication —
Part 10101: Nomenclature
ISO/IEEE 11073-10102:2014, Health informatics — Point-of-care medical device communication —
Part 10102: Nomenclature — Annotated ECG[9]
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
acquiring cardiograph / acquiring device
cardiograph/device recording the original ECG signal
3.2
analysis Time Window
defines the time interval (starting date and time and duration) that will be used to select an ECG excerpt
that will be analysed by a computer program and/or by a health professional viz a cardiologist
3.3
confirming
process whereby a trained and experienced cardiologist reviews the computer-generated (or already
overread) interpretation of an ECG in order to confirm the computer-generated (or already overread)
interpretation or to make the final changes to the interpretation text. The confirmed ECG is the final
clinically acceptable version for diagnosis and treatment

2
Impacted by ISO/IEEE 11073-10101:2004/Amd.1:2017
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3.4
CSE Project
project supported by DG XII of the European Commission aiming at the development of Common
Standards for (Quantitative) Electrocardiography (see references [32] and [44] to [50])
3.5
ECG excerpt
portion of a continuous ECG recording that has been either visually selected by a health professional or
by a computer based algorithm or according to a predefined protocol (viz a 10 s excerpt every hour)
3.6
interpretive device
device (cardiograph, wearable equipment, smartphone, computer, cloud, etc.) analysing and interpreting
the ECG signal
3.7
message
textual body of information
3.8
overreading
process whereby a cardiologist or a cardiology fellow reviews the computer-generated interpretation of
an ECG in order to verify the accuracy or to make changes to the interpretation text
NOTE 1 to entry: An overread ECG is generally not the final clinically acceptable version for diagnosis and
treatment. Usually, the overreading process precedes the confirming process.
3.9
record
entire data file which is transmitted, including the ECG data and associated information, such as patient
identification, demographic and other clinical data, measurements, annotations, interpretation results,
etc.
3.10
reference beat
reference/representative ECG cycle computed through any (but not specified) algorithm comprising the
P, QRS and the ST-T waves
3.11
rhythm data
full original ECG data, or the decompressed and reconstructed ECG data if lossless compression is used
NOTE 1 to entry: Rhythm data are typically 10 s in length for a standard 12-Lead ECG (stored in sections 6 and/or
14), but may last several minutes for stress tests, a few hours for drug trials and up to 7 days for Holter recordings
(stored in section 12).
3.12
section
aggregate of data elements related to one aspect of the electrocardiographic recording, measurement,
annotation or interpretation
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3.13
universal statement codes
ECG interpretation codes described in Annex B of this document
NOTE 1 to entry: See glossary in Annex G for other technical terms related to this part of EN 1064.
4 Symbols and abbreviated terms
AAMI American Association for the Advancement of Medical Instrumentation
AC Alternating Current
AHA American Heart Association
AIM Advanced Informatics for Medicine Programs of the European Commission Directorate
General XIII
ANSI American National Standards Institute
ASCII American Standard Code for Information Interchange
AVM Amplitude Value Multiplier (see 5.8.3)
CEN Comité Européen de Normalisation - European Committee for Standardization
CIED Cardiac Implantable Electronic Device
CRC Cyclic Redundancy Check
CRT Implanted Cardiac Resynchronization Therapy device
CSE Common Standards for quantitative Electrocardiography
DG Directorate General (of the European Commission)
EU European Union
ECG Electrocardiogram
EN Europäische Norm (European Standard)
ENV Europäische Norm Vorausgabe (European Pre-standard)
ICD Implanted Cardioverter Defibrillator
ID Identification
IEC International Electrotechnical Commission
IEEE Institute of Electrical and Electronic Engineers
ISO International Organization for Standardization
LSB Least significant bit
MSB Most significant bit
RMS Root Mean Square
SCP Standard Communications Protocol
SCP-ECG Standard Communications Protocol for computerized Electrocardiography
TC Technical Committee
UTF-8 Universal Coded Character Set + Transformation Format – 8-bit (specified in
ISO/IEC 10646)
VCG Vectorcardiogram
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5 Definition of the data contents and format
5.1 General considerations
5.1.1 The data record which is to be interchanged shall be divided into different sections. The contents
and format of each of these sections are defined in this document.
5.1.2 All text data (character strings) shall be stored in the 8-bit Universal Character Set
Transformation Format of ISO/IEC 10646 (also known as UTF-8)
5.1.3 All character strings shall be encoded in UTF-8 and NULL terminated
5.1.4 For all signed binary values 2's-complement coding shall be applied
5.1.5 All single and multiple byte binary values are regarded as unsigned integers, if not otherwise
specified
5.1.6 Endianness: binary values spanning more than 1 byte shall be transmitted and/or stored
according to the little endian mode, i.e. in ascending order of significance (the least significant byte is
transmitted and/or stored first, the most significant byte last)
5.1.7 Consecutive bytes are numbered from left to right (starting with 1). Bits of a byte are numbered
from right to left (0 = LSB, 7 = MSB)
5.1.8 The first byte in the record (i.e. the first byte of the Checksum) is defined as Byte 1
5.1.9 ECG samples are indexed and numbered starting with sample number 1. Sample index 0 is not
used in the present document. Sample indexes are stored as ones-based 16-bit or 32–bit unsigned
integers. The first sample starts at time 0. The second sample is at time (0 + 2) ms in case of 500 samples/s
sampling rate
5.1.10 Sections are numbered starting from 0 (the Pointer Section) to 32 767
5.1.11 The term “Reference Beat” used in this document refers to an ECG complex which is chosen as
representative of a class of such complexes. No specific statistical meaning is implied by this term; for
example, it may be an averaged beat (obtained by averaging the waveforms of a set of beats of the same
type), a “Median Beat” (obtained by computing the median of the waveforms of a set of beats of the same
type), a selected or any other representative single cycle taken from the total ECG recording. This
“Reference Beat” does include the P-wave if present (not in case of atrial fibrillation), the ST-T segment
and the T wave of this beat
An ECG may have multiple reference beats. The term “reference Beat type” used in this document refers
to any one of an ordered list of reference beats, starting with reference beat type 0 (zero). Reference beat
type 0 (sometimes also called “dominant beat”) is, in general, the primary heart beat excepting
extrasystole or artefact. It is used for the calculation of the full set of global measurements and the per-
lead measurements stored in sections 7 (Clause 5.10) and 10 (Clause 5.13) and is, by definition, the
reference beat used for the so-called contour interpreta
...

SLOVENSKI STANDARD
oSIST prEN 1064:2018
01-oktober-2018
=GUDYVWYHQDLQIRUPDWLND6WDQGDUGQLNRPXQLNDFLMVNLSURWRNRO5DþXQDOQLãNR
SRGSUWDHOHNWURNDUGLRJUDILMD
Health informatics - Standard communication protocol - Computer-assisted
electrocardiography
Medizinische Informatik - Standardkommunikationsprotokoll - Computergestützte
Elektrokardiographie; Englische Fassung EN 1064:2005+A1:2007
Informatique de Santé - Protocole de Communication Standard pour
L'Electrocardiographie Assistée par Ordinateur
Ta slovenski standard je istoveten z: prEN 1064
ICS:
35.240.80 Uporabniške rešitve IT v IT applications in health care
zdravstveni tehniki technology
oSIST prEN 1064:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 1064:2018

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oSIST prEN 1064:2018


DRAFT
EUROPEAN STANDARD
prEN 1064
NORME EUROPÉENNE

EUROPÄISCHE NORM

August 2018
ICS 35.240.80 Will supersede EN 1064:2005+A1:2007
English Version

Health informatics - Standard communication protocol -
Computer-assisted electrocardiography
Informatique de Santé - Protocole de Communication Medizinische Informatik -
Standard pour L'Electrocardiographie Assistée par Standardkommunikationsprotokoll -
Ordinateur Computergestützte Elektrokardiographie; Englische
Fassung EN 1064:2005+A1:2007
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 251.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1064:2018 E
worldwide for CEN national Members.

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prEN 1064:2018 (E)
Contents Page
Introduction . 3
1 Scope . 5
2 Normative references . 6
3 Terms and definitions . 6
4 Symbols and abbreviated terms . 8
5 Definition of the data contents and format . 9
5.1 General considerations . 9
5.2 Specifications for the data structure . 10
5.3 Pointer section – Section 0 . 15
5.4 Header information - Patient data / ECG metadata – Section 1 . 16
5.5 Huffman tables – Section 2 . 35
5.6 ECG leads definition – Section 3 . 38
5.7 Reserved for legacy SCP-ECG versions – Section 4 . 46
5.8 Encoded type 0 reference beat data – Section 5 . 48
5.9 Short-term ECG Rhythm data – Section 6. 51
5.10 Global ECG measurements – Section 7 . 53
5.11 Storage of full text interpretive statements – Section 8 . 66
5.12 Storage of manufacturer specific interpretive statements and data related to the
overreading trail – Section 9 . 68
5.13 Per-lead ECG measurements – Section 10 . 68
5.14 Storage of the universal ECG interpretive statement codes – Section 11 . 77
5.15 Long-term ECG rhythm data – Section 12 . 81
5.16 Stress tests, Drug trials and Protocol based ECG recordings Metadata – Section 13 . 86
5.17 Selected ECG Sequences Repository – Section 14 . 97
5.18 Beat-by-Beat ECG measurements and annotations – Section 15 . 101
5.19 Selected ECG beats measurements and annotations – Section 16 . 116
5.20 Pacemaker Spikes measurements and annotations – Section 17 . 125
5.21 Additional ECG annotations – Section 18 . 139
Annex A (normative) Supplementary information and additional encoding specifications . 146
Annex B (informative)  Universal ECG interpretation statements codes . 154
Annex C (informative) Definition of compliance with the SCP ECG standard . 180
Annex D (Informative) Methodology of the recommended ECG signal compression technique . 189
Annex E (informative) Cross-references to other ECG standards . 225
Annex F (informative) Implementation Recommendations . 228
Annex G (informative) Glossary . 230
Bibliography . 232

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Introduction
The electrocardiogram (ECG) is a recording of voltage changes transmitted to the body surface by
electrical events in the heart muscle, providing direct evidence of cardiac rhythm and conduction, and
indirect evidence of certain aspects of myocardial anatomy, blood supply and function. During its
propagation to the surface, extracardiac tissues may intervene and influence the ECG morphology.
Electrocardiography has been used for many years, and is increasingly used as a key, non-invasive and
low cost method in the diagnosis and early detection of coronary heart disease, which is the leading cause
1
of mortality worldwide [56] . Of the 57 million global deaths in 2008, 36 million (63 %) were due to non-
communicable diseases (NCDs) and 17.3 million (30 %) were due to cardiovascular diseases (CVDs). Out
of these 17.3 million cardiovascular deaths, heart attacks were responsible for 7.3 million and strokes
were responsible for 6.2 million deaths. More than 3 million of these 17.3 million CVD deaths occurred
before the age of 60. The percentage of premature deaths from CVDs ranges from 4 % in high-income
countries to 42 % in low-income countries [56].
In 2008, it was estimated that more than 300 million standard 12 lead ECGs are recorded yearly in the
US for routine diagnostic and screening purposes [37]. The Mayo Clinic, for example, nowadays performs
about 240,000 standard ECG recordings per year [58].
According to Transparency Market Research, the overall shipment of ECG monitoring systems including
resting ECG recorders, ECG stress testing systems, Event recorders and Holter monitors, will rise from
262.1 thousand units in 2011 to 374.8 thousand units in 2016, with a 2016 market size estimation of
US$822.1 million [59]. Marketsandmarkets.com on its side estimates that the global Diagnostic ECG
Market will reach $5,435 million by 2020 [57]. The factors driving this market include the increasing
geriatric population, rising incidences of lifestyle diseases, technological advancements in diagnostic ECG
devices, and high growth rate in developing countries.
Almost all newer electrocardiographs nowadays use digital recording, interpretation and communication
techniques, and there is an increasing number of portable and even wearable (mobile) ECG devices that
are now used instead of the traditional ECG cart. These stand-alone, microprocessor based machines and
devices can be connected to each other, to a host computer, to the internet or to a hospital information
system for reporting, long-term storage in the Medical Electronic Record and serial comparison. To this
end, various manufacturers have used different techniques.
It is in the general public interest for users not to be restricted in their options by incompatible technical
features and services of different systems and devices. ECG processing is increasingly being integrated
with various other types of data processing in health care. This evolution will have considerable impact
on the storage and communication of ECG data. There are many different end-users who for different
purposes (support of patient care, management, drug trials and/or drug management, research and
education) want to obtain a copy of the signal data, of the interpretive report and/or measurement
results. Being one of the very first ever developed systems for medical decision support, computerized
ECG interpretation stretches from departments of cardiology in hospitals, to general practitioners in
primary care and health care centres and to home care. In life-threatening acute myocardial infarction,
ECGs are now used in ambulances by paramedical personnel to assess the necessity for administering
thrombolytic agents or to alert cathlabs to prepare for a coronary intervention, with long-distance
monitoring whenever possible, and in self-care situations to detect ischemia or life threatening
arrhythmias as early as possible [31].
To facilitate the exchange of information between various systems, it was of utmost importance that a
standard communications protocol for computer-aided electrocardiography (SCP-ECG) was established,
as defined in this document. Its aim is to specify a data format for transferring ECG signals, metadata and

1
Figures in square brackets refer to the Bibliography.
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reports from any vendor's computerized ECG device to any other's vendor central ECG management
system. The same standard should also allow standardized transfer of digitised ECG data and results
between various computer and information systems, Electronic Medical Records, and ECG data
repositories.
Under this standard communications protocol (SCP-ECG), the contents and format of the ECG waveform
data, metadata and the measurements from ECG devices of different manufacturers are not expected to
be identical. As a result, the determination of the suitability of a device and/or system for any particular
application remains with the user/purchaser. The following possible uses of ECG records require special
attention:
— serial comparison of ECGs and interpretations;
— printout formats of ECGs;
— maintaining an audit trail of edits and annotations;
— integration into an electronic medical record;
— integration into clinical information systems and data repositories.
The users are cautioned to make sure that the data contents and format of the waveform data, metadata,
measurements, and the interpretive statements meet their specific needs. If more than one type of ECG
device and/or ECG management system is interconnected, the user is also advised to verify with the
manufacturers that the data from different systems and devices are compatible with each other and with
the user’s needs.
In order to understand this document, the reader needs some basic knowledge of electrocardiology,
electrocardiography and signal processing.
This document not only relates to the conventional recording of the electrocardiogram, i.e. the so-called
standard 12-lead electrocardiogram and the vectorcardiogram (VCG), but also to other types of ECG such
as Holter ECG, physiologic monitoring ECG, stress ECG, intracardiac ECG, home care ECG monitoring and
wearable self-care ECG devices. Initially, the electric connections used for recording the ECG were made
to the limbs only. These connections to the right arm (RA), left arm (LA) and left leg (LL) were introduced
by Einthoven. The electrical variations detected by these electrode connections are algebraically
combined to form the bipolar leads I, II, and III. Lead I, for example records the difference between the
voltages of the electrodes placed on the left arm and the right arm. The unipolar electrocardiographic
leads (VR, VL, VF and the precordial leads V1 to V6) were introduced much later, starting in 1933. In these
leads, potentials are recorded at one location with respect to a level which does not vary significantly in
electrical activity during cardiac contraction. The “augmented” limb lead potentials (aVR, aVL, aVF) are
recorded with reference to the average potential of (L+F), (R+F) and (L+R) respectively, where R, L and
F refer to the RA, LA and LL electrodes. The unipolar chest leads are recorded with reference to the
average potential of (RA+RL+LL)/3 which is called the Wilson “central terminal” (CT). In
vectorcardiography recordings are made from three mutually orthogonal leads, running parallel to one
of the rectilinear coordinate axes of the body. The axes are the x-axis going right to left, the y-axis with a
top to bottom orientation, and the Z or front to back axis. In 12-Lead stress ECG recordings, the limb
electrodes are placed on the torso to reduce limb movement artefacts. The same electrode positions apply
to some Holter, emergency and home care recordings, both to limit movement artefacts and undressing.
In some research centres, so-called body surface maps are obtained by placing many (from 24 to 124 or
even more) closely spaced electrodes around the torso. This document has not been designed to handle
exchange of such recordings, although future extensions could be made to this end. The standard has also
not been designed to exchange specialized recordings of intracardiac potentials (electrograms) recorded
in the EP (Electrophysiology) laboratories or by cardiac implantable electronic devices (CIED), viz
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pacemakers, implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT)
devices, although it could also be used to this intent.
ECG computer processing can be reduced to 3 principal stages:
1) data acquisition, encoding, transmission and storage;
2) pattern recognition and feature extraction, i.e. ECG measurement;
3) diagnostic classification.
In each of these stages there are important needs for standardization and quality assurance testing. The
scope of this document is confined to the first of these three stages. Quality assurance of ECG
measurement and diagnostic classification have been addressed by the CSE Working Party and to some
extent by IEC 60601-2-25:2011 [4]. The latter also addresses the issue of quality assurance testing of the
signal acquisition hardware and filtering.
The various data sections that shall be transmitted by means of the standard ECG communications
protocol are defined in Clause 5 of this document.
The selection and definition of ECG specific high-level syntaxes and query languages for transfer of
messages and data between devices or between devices and hosts or host-to-hosts, using for example
Bluetooth, TCP/IP, FTP, USB, Filesystem, HL7, etc., are beyond the scope of this document.
The main goal of the SCP-ECG standard is to address ECG data and related metadata structuring,
semantics and syntax, with the objective of facilitating interoperability and thus to support and promote
the exchange of the relevant information for ECG diagnosis. Indeed, as recommended by the
ACC/AHA/ACP-ASIM task force: “Electrocardiogram readers should understand the importance of
comparing a current tracing to previous tracings in order to make correct diagnoses. All abnormal
tracings should be compared with available previous tracings. The accuracy of some diagnoses may be
considerably enhanced by reviewing previous tracings.” [33]. It is thus of utmost importance to provide
a storage format enabling any device or computer program performing the analysis and interpretation of
a current ECG to perform a reliable re-analysis of the previous ECGs. For assessing serial changes between
ECG measurements it is necessary that the measurements are computed in the same way on each
recording in order to avoid any bias.
The binary encoding of ECG data within SCP-ECG and the included content self-control capabilities allow
for an efficient encoding, an encapsulation of all ECG-related parameters, and a small memory footprint
compliant with mHealth scenarios for an early detection of cardiac diseases, anywhere and anytime [31],
[40]. These features not only provide an advantage in data transmission and archiving, but also when the
data need to be encrypted (for protecting the data and the confidentiality), or signed (protection against
changes).
1 Scope
This document specifies the common conventions required for the interchange of specific patient data
(demographic, recording conditions .), ECG signal data and metadata, ECG measurements and ECG
annotations, and ECG interpretation results.
This document specifies the content and structure of the information which is to be interchanged
between digital ECG electrocardiographs/devices and computer ECG management systems, as well as
other computer or information systems (cloud, etc.) where ECG data can be stored.
This document defines the way to describe and encode standard and medium to long-term
electrocardiogram waveforms measured in physiological laboratories, hospital wards, clinics and
primary care medical check-ups, ambulatory and home care. It covers electrocardiograms such as 12-
lead, 15-lead, 18-lead, Cabrera lead, Nehb lead, Frank lead, XYZ lead, Holter ECGs and exercise ECGs that
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are recorded, measured and analysed by equipment such as electrocardiographs, patient monitors,
wearable devices. It also covers intracardiac electrograms recorded by implantable devices as well as the
analysis results of ECG analysis and interpretation systems and software that are compatible with SCP-
ECG.
ECG waveforms and data that are not in the scope of this technical specification include real-time ECG
waveform encoding and analysis used for physiological monitors, and intra-cardiac or extra cardiac ECG
mapping.
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/IEC 10646, Information technology — Universal Coded Character Set (UCS)
2
ISO/IEEE 11073-10101:2004, Health informatics — Point-of-care medical device communication —
Part 10101: Nomenclature
ISO/IEEE 11073-10102:2014, Health informatics — Point-of-care medical device communication —
Part 10102: Nomenclature — Annotated ECG[9]
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
acquiring cardiograph / acquiring device
cardiograph/device recording the original ECG signal
3.2
analysis Time Window
defines the time interval (starting date and time and duration) that will be used to select an ECG excerpt
that will be analysed by a computer program and/or by a health professional viz a cardiologist
3.3
confirming
process whereby a trained and experienced cardiologist reviews the computer-generated (or already
overread) interpretation of an ECG in order to confirm the computer-generated (or already overread)
interpretation or to make the final changes to the interpretation text. The confirmed ECG is the final
clinically acceptable version for diagnosis and treatment

2
Impacted by ISO/IEEE 11073-10101:2004/Amd.1:2017
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3.4
CSE Project
project supported by DG XII of the European Commission aiming at the development of Common
Standards for (Quantitative) Electrocardiography (see references [32] and [44] to [50])
3.5
ECG excerpt
portion of a continuous ECG recording that has been either visually selected by a health professional or
by a computer based algorithm or according to a predefined protocol (viz a 10 s excerpt every hour)
3.6
interpretive device
device (cardiograph, wearable equipment, smartphone, computer, cloud, etc.) analysing and interpreting
the ECG signal
3.7
message
textual body of information
3.8
overreading
process whereby a cardiologist or a cardiology fellow reviews the computer-generated interpretation of
an ECG in order to verify the accuracy or to make changes to the interpretation text
NOTE An overread ECG is generally not the final clinically acceptable version for diagnosis and treatment.
Usually, the overreading process precedes the confirming process.
3.9
record
entire data file which is transmitted, including the ECG data and associated information, such as patient
identification, demographic and other clinical data, measurements, annotations, interpretation results,
etc.
3.10
reference beat
reference/representative ECG cycle computed through any (but not specified) algorithm comprising the
P, QRS and the ST-T waves
3.11
rhythm data
full original ECG data, or the decompressed and reconstructed ECG data if lossless compression is used
NOTE Rhythm data are typically 10 s in length for a standard 12-Lead ECG (stored in sections 6 and/or 14),
but may last several minutes for stress tests, a few hours for drug trials and up to 7 days for Holter recordings
(stored in section 12).
3.12
section
aggregate of data elements related to one aspect of the electrocardiographic recording, measurement,
annotation or interpretation
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3.13
universal statement codes
ECG interpretation codes described in Annex B of this document
NOTE See glossary in Annex G for other technical terms related to this part of EN 1064.
4 Symbols and abbreviated terms
AAMI American Association for the Advancement of Medical Instrumentation
AC Alternating Current
AHA American Heart Association
AIM Advanced Informatics for Medicine Programs of the European Commission Directorate
General XIII
ANSI American National Standards Institute
ASCII American Standard Code for Information Interchange
AVM Amplitude Value Multiplier (see 5.8.3)
CEN Comité Européen de Normalization - European Committee for Standardization
CIED Cardiac Implantable Electronic Device
CRC Cyclic Redundancy Check
CRT Implanted Cardiac Resynchronization Therapy device
CSE Common Standards for quantitative Electrocardiography
DG Directorate General (of the European Commission)
EU European Union
ECG Electrocardiogram
EN Europäische Norm (European Standard)
ENV Europäische Norm Vorausgabe (European Pre-standard)
ICD Implanted Cardioverter Defibrillator
ID Identification
IEC International Electrotechnical Commission
IEEE Institute of Electrical and Electronic Engineers
ISO International Organization for Standardization
LSB Least significant bit
MSB Most significant bit
RMS Root Mean Square
SCP Standard Communications Protocol
SCP-ECG Standard Communications Protocol for computerized Electrocardiography
TC Technical Committee
UTF-8 Universal Coded Character Set + Transformation Format – 8-bit (specified in
ISO/IEC 10646)
VCG Vectorcardiogram
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5 Definition of the data contents and format
5.1 General considerations
5.1.1 The data record which is to be interchanged shall be divided into different sections. The contents
and format of each of these sections are defined in this document.
5.1.2 All text data (character strings) shall be stored in the 8-bit Universal Character Set
Transformation Format of ISO/IEC 10646 (also known as UTF-8)
5.1.3 All character strings shall be encoded in UTF-8 and NULL terminated
5.1.4 For all signed binary values 2's-complement coding shall be applied
5.1.5 All single and multiple byte binary values are regarded as unsigned integers, if not otherwise
specified
5.1.6 Endianness: binary values spanning more than 1 byte shall be transmitted and/or stored
according to the little endian mode, i.e. in ascending order of significance (the least significant byte is
transmitted and/or stored first, the most significant byte last)
5.1.7 Consecutive bytes are numbered from left to right (starting with 1). Bits of a byte are numbered
from right to left (0 = LSB, 7 = MSB)
5.1.8 The first byte in the record (i.e. the first byte of the Checksum) is defined as Byte 1
5.1.9 ECG samples are indexed and numbered starting with sample number 1. Sample index 0 is not
used in the present document. Sample indexes are stored as ones-based 16-bit or 32–bit unsigned
integers. The first sample starts at time 0. The second sample is at time (0 + 2) ms in case of 500 samples/s
sampling rate
5.1.10 Sections are numbered starting from 0 (the Pointer Section) to 32 767
5.1.11 The term “Reference Beat” used in this document refers to an ECG complex which is chosen as
representative of a class of such complexes. No specific statistical meaning is implied by this term; for
example, it may be an averaged beat (obtained by averaging the waveforms of a set of beats of the same
type), a “Median Beat” (obtained by computing the median of the waveforms of a set of beats of the same
type), a selected or any other representative single cycle taken from the total ECG recording. This
“Reference Beat” does include the P-wave if present (not in case of atrial fibrillation), the ST-T segment
and the T wave of this beat
An ECG may have multiple reference beats. The term “reference Beat type” used in this document refers
to any one of an ordered list of reference beats, starting with reference beat type 0 (zero). Reference beat
type 0 (sometimes also called “dominant beat”) is, in general, the primary heart beat excepting
extrasystole or artefact. It is used for the calculation of the full set of global measurements and the per-
lead measurements stored in sections 7 (Clause 5.10) and 10 (Clause 5.13) and is, by definition, the
reference beat used for the so-called contour interpretation of the ECG. The ordering of
...