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Research paper thumbnail of Prevalence of long and short QT in a young population of 41,767 predominantly male Swiss conscripts

Heart Rhythm, 2009

BACKGROUND Abnormally long and short QT intervals are recognized to be associated with an increas... more BACKGROUND Abnormally long and short QT intervals are recognized to be associated with an increased risk for life-threatening ventricular arrhythmias. It is therefore important to define the upper and lower border of the normal QT. OBJECTIVE The aim of this study was to describe the normal distribution of the QT interval in a contemporary population of young conscripts and to define long and short limits of the QT interval. METHODS In Switzerland, all young male citizens must undergo compulsory conscription for the Swiss Army at the age of 18 to 19 years. In every conscript, an electrocardiogram (ECG) is performed. Retrospectively, 41,767 consecutive ECGs of Swiss citizens who underwent conscription for the army between March 1, 2004, and July 31, 2006, were analyzed. RESULTS The mean QTc Bazett interval was 394 Ϯ 22 ms. One percent of the conscripts had a Bazett QTc shorter than 347 ms, and one percent had a Bazett QTc longer than 445 ms, respectively. None of the subjects presented a QTc Bazett Ͻ 300 ms; the prevalence of a QTc Bazett Ͻ 320 ms was 0.02%. CONCLUSION The present study shows the distribution of QT intervals in an unselected young population. Because none of the subjects presented a QTc Ͻ 300 ms, it may be concluded that the short QT syndrome is a very rare entity in the population of young male adults.

Research paper thumbnail of The New ISO/IEC Standard for Automated ECG Interpretation

Hearts, 2021

Updates to industry consensus standards for ECG equipment is a work-in-progress by the ISO/IEC Jo... more Updates to industry consensus standards for ECG equipment is a work-in-progress by the ISO/IEC Joint Work Group 22. This work will result in an overhaul of existing industry standards that apply to ECG electromedical equipment and will result in a new single international industry, namely 80601-2-86. The new standard will be entitled “80601, Part 2-86: Particular requirements for the basic safety and essential performance of electrocardiographs, including diagnostic equipment, monitoring equipment, ambulatory equipment, electrodes, cables, and leadwires”. This paper will provide a high-level overview of the work in progress and, in particular, will describe the impact it will have on requirements and testing methods for computerized ECG interpretation algorithms. The conclusion of this work is that manufacturers should continue working with clinical ECG experts to make clinically meaningful improvements to automated ECG interpretation, and the clinical validation of ECG analysis alg...

Research paper thumbnail of Updates to IEC/AAMI ECG standards, a new hybrid standard

Journal of Electrocardiology, 2018

Available online xxxx The current set of IEC particular standards that pertain to electrocardiogr... more Available online xxxx The current set of IEC particular standards that pertain to electrocardiograph (ECG) devices, namely, 60601-2-25, 60601-2-27, and 60601-2-47, which define requirements and testing for the essential performance and basic safety of diagnostic ECG, ECG monitoring and ambulatory ECG systems, respectively. These standards have been harmonized with the corresponding AAMI standards, namely EC11, EC13 and EC38. Together these standards have been in existence for decades and have evolved separately even though the technology used in these three clinical applications is very similar. A work proposal was initiated in the ISO/IEC Joint Work Group 22 (JWG22), which over sees the revision of these standards, to update the standards by creating a single new hybrid standard. The goal of this work is a joint endeavor between ISO and IEC to combine the three separate particular standards that cover ECG device and to harmonize the similar requirements that are common across all three types of devices into one set of general requirements. The requirements that separate specific to meeting the intended use and essential performance for each of the 3 types of devices (diagnostic, patient monitoring, and ambulatory ECG recording) will continue to remain as separate requirements. Furthermore, manufactures of ECG devices have also been required to meet standards for disposable electrodes (AAMI EC12), ECG cables and leadwires (AAMI EC53), and arrhythmia analysis performance reporting (AAMI EC57). In addition to the primary goal, a secondary goal for the JW22 work is to also incorporate these three AAMI standards into the ECG hybrid standard. This paper describes the work being done and highlights key updates, and explains the rationale for approaches and changes being made. The Joint Work Group is currently in the process of updating the committee draft of the new hybrid standard before requesting comments from National Standard Committees participating in JWG22.

Research paper thumbnail of Prevalence of long and short QT in a young population of 41,767 predominantly male Swiss conscripts

Heart Rhythm, 2009

BACKGROUND Abnormally long and short QT intervals are recognized to be associated with an increas... more BACKGROUND Abnormally long and short QT intervals are recognized to be associated with an increased risk for life-threatening ventricular arrhythmias. It is therefore important to define the upper and lower border of the normal QT. OBJECTIVE The aim of this study was to describe the normal distribution of the QT interval in a contemporary population of young conscripts and to define long and short limits of the QT interval. METHODS In Switzerland, all young male citizens must undergo compulsory conscription for the Swiss Army at the age of 18 to 19 years. In every conscript, an electrocardiogram (ECG) is performed. Retrospectively, 41,767 consecutive ECGs of Swiss citizens who underwent conscription for the army between March 1, 2004, and July 31, 2006, were analyzed. RESULTS The mean QTc Bazett interval was 394 Ϯ 22 ms. One percent of the conscripts had a Bazett QTc shorter than 347 ms, and one percent had a Bazett QTc longer than 445 ms, respectively. None of the subjects presented a QTc Bazett Ͻ 300 ms; the prevalence of a QTc Bazett Ͻ 320 ms was 0.02%. CONCLUSION The present study shows the distribution of QT intervals in an unselected young population. Because none of the subjects presented a QTc Ͻ 300 ms, it may be concluded that the short QT syndrome is a very rare entity in the population of young male adults.

Research paper thumbnail of The New ISO/IEC Standard for Automated ECG Interpretation

Hearts, 2021

Updates to industry consensus standards for ECG equipment is a work-in-progress by the ISO/IEC Jo... more Updates to industry consensus standards for ECG equipment is a work-in-progress by the ISO/IEC Joint Work Group 22. This work will result in an overhaul of existing industry standards that apply to ECG electromedical equipment and will result in a new single international industry, namely 80601-2-86. The new standard will be entitled “80601, Part 2-86: Particular requirements for the basic safety and essential performance of electrocardiographs, including diagnostic equipment, monitoring equipment, ambulatory equipment, electrodes, cables, and leadwires”. This paper will provide a high-level overview of the work in progress and, in particular, will describe the impact it will have on requirements and testing methods for computerized ECG interpretation algorithms. The conclusion of this work is that manufacturers should continue working with clinical ECG experts to make clinically meaningful improvements to automated ECG interpretation, and the clinical validation of ECG analysis alg...

Research paper thumbnail of Updates to IEC/AAMI ECG standards, a new hybrid standard

Journal of Electrocardiology, 2018

Available online xxxx The current set of IEC particular standards that pertain to electrocardiogr... more Available online xxxx The current set of IEC particular standards that pertain to electrocardiograph (ECG) devices, namely, 60601-2-25, 60601-2-27, and 60601-2-47, which define requirements and testing for the essential performance and basic safety of diagnostic ECG, ECG monitoring and ambulatory ECG systems, respectively. These standards have been harmonized with the corresponding AAMI standards, namely EC11, EC13 and EC38. Together these standards have been in existence for decades and have evolved separately even though the technology used in these three clinical applications is very similar. A work proposal was initiated in the ISO/IEC Joint Work Group 22 (JWG22), which over sees the revision of these standards, to update the standards by creating a single new hybrid standard. The goal of this work is a joint endeavor between ISO and IEC to combine the three separate particular standards that cover ECG device and to harmonize the similar requirements that are common across all three types of devices into one set of general requirements. The requirements that separate specific to meeting the intended use and essential performance for each of the 3 types of devices (diagnostic, patient monitoring, and ambulatory ECG recording) will continue to remain as separate requirements. Furthermore, manufactures of ECG devices have also been required to meet standards for disposable electrodes (AAMI EC12), ECG cables and leadwires (AAMI EC53), and arrhythmia analysis performance reporting (AAMI EC57). In addition to the primary goal, a secondary goal for the JW22 work is to also incorporate these three AAMI standards into the ECG hybrid standard. This paper describes the work being done and highlights key updates, and explains the rationale for approaches and changes being made. The Joint Work Group is currently in the process of updating the committee draft of the new hybrid standard before requesting comments from National Standard Committees participating in JWG22.