Systematic Comparisons of Electrocardiographic Morphology Increase the Precision of QT Interval Measurement
Identifieur interne : 001941 ( Main/Corpus ); précédent : 001940; suivant : 001942Systematic Comparisons of Electrocardiographic Morphology Increase the Precision of QT Interval Measurement
Auteurs : Katerina Hnatkova ; Peter Smetana ; Ondrej Toman ; Axel Bauer ; Georg Schmidt ; Marek MalikSource :
- Pacing and Clinical Electrophysiology [ 0147-8389 ] ; 2009-01.
English descriptors
Abstract
Decreased intrasubject variability of QTc values is needed to increase the power and reduce the size of the so‐called thorough QT studies. One source of QTc variability is the lack of systematic measurements when electrocardiograms (ECG) with closely matching morphologies are not measured in an exactly corresponding way. The inaccuracy can be eliminated by postprocessing of QT measurements by ECG pattern matching. This study tested the effects of pattern matching in ECG measurements in two populations of healthy subjects (n = 48 + 56) and in a population of patients with advanced Parkinson's disease (n = 130) in whom both day‐time and night‐time data were available. Intrasubject QTc variability was measured by intrasubject standard deviations (SD) of QTc values obtained with manual measurements before and after pattern‐matching measurement alignments. In each subject, QT values (n = 230–320) in one drug‐free long‐term ECG recording were evaluated. The pattern‐matching adjustment of the QT measurement decreased the intrasubject QTc variability from 5.2 ± 1.0 to 4.5 ± 1.0 ms (P < 10−14) from 6.4 ± 1.7 to 5.5 ± 1.6 ms (P < 10−10) from 5.6 ± 1.5 to 4.6 ± 1.4 ms (P < 10−34) and from 6.1 ± 1.9 to 5.0 ± 1.7 ms (P < 10−33), in the two populations of healthy subjects and in the day‐time and night‐time recordings of Parkinson's disease patients, respectively. Hence, morphological pattern adjustment of QT interval measurements improves the quality of the QT data with substantial practical implications. Reductions in intrasubject QTc variability were reproducibly found in different populations and thus the technology might be recommended for every thorough QT/QTc study. Noticeable reductions of necessary study size are likely achievable in this way.
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DOI: 10.1111/j.1540-8159.2009.02185.x
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<record><TEI wicri:istexFullTextTei="biblStruct"><teiHeader><fileDesc><titleStmt><title xml:lang="en">Systematic Comparisons of Electrocardiographic Morphology Increase the Precision of QT Interval Measurement</title><author><name sortKey="Hnatkova, Katerina" sort="Hnatkova, Katerina" uniqKey="Hnatkova K" first="Katerina" last="Hnatkova">Katerina Hnatkova</name><affiliation><mods:affiliation>St. Paul's Cardiac Electrophysiology, London, United Kingdom</mods:affiliation></affiliation></author><author><name sortKey="Smetana, Peter" sort="Smetana, Peter" uniqKey="Smetana P" first="Peter" last="Smetana">Peter Smetana</name><affiliation><mods:affiliation>Wilhelminenspital der Stadt Wien, Vienna, Austria</mods:affiliation></affiliation></author><author><name sortKey="Toman, Ondrej" sort="Toman, Ondrej" uniqKey="Toman O" first="Ondrej" last="Toman">Ondrej Toman</name><affiliation><mods:affiliation>University Hospital Brno, Masaryk University, Brno, Czech Republic</mods:affiliation></affiliation></author><author><name sortKey="Bauer, Axel" sort="Bauer, Axel" uniqKey="Bauer A" first="Axel" last="Bauer">Axel Bauer</name><affiliation><mods:affiliation>1. 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One source of QTc variability is the lack of systematic measurements when electrocardiograms (ECG) with closely matching morphologies are not measured in an exactly corresponding way. The inaccuracy can be eliminated by postprocessing of QT measurements by ECG pattern matching. This study tested the effects of pattern matching in ECG measurements in two populations of healthy subjects (n = 48 + 56) and in a population of patients with advanced Parkinson's disease (n = 130) in whom both day‐time and night‐time data were available. Intrasubject QTc variability was measured by intrasubject standard deviations (SD) of QTc values obtained with manual measurements before and after pattern‐matching measurement alignments. In each subject, QT values (n = 230–320) in one drug‐free long‐term ECG recording were evaluated. The pattern‐matching adjustment of the QT measurement decreased the intrasubject QTc variability from 5.2 ± 1.0 to 4.5 ± 1.0 ms (P < 10−14) from 6.4 ± 1.7 to 5.5 ± 1.6 ms (P < 10−10) from 5.6 ± 1.5 to 4.6 ± 1.4 ms (P < 10−34) and from 6.1 ± 1.9 to 5.0 ± 1.7 ms (P < 10−33), in the two populations of healthy subjects and in the day‐time and night‐time recordings of Parkinson's disease patients, respectively. Hence, morphological pattern adjustment of QT interval measurements improves the quality of the QT data with substantial practical implications. Reductions in intrasubject QTc variability were reproducibly found in different populations and thus the technology might be recommended for every thorough QT/QTc study. Noticeable reductions of necessary study size are likely achievable in this way.</div></front></TEI><istex><corpusName>wiley</corpusName><author><json:item><name>KATERINA HNATKOVA Ph.D.</name><affiliations><json:string>St. Paul's Cardiac Electrophysiology, London, United Kingdom</json:string></affiliations></json:item><json:item><name>PETER SMETANA M.D., Ph.D.</name><affiliations><json:string>Wilhelminenspital der Stadt Wien, Vienna, Austria</json:string></affiliations></json:item><json:item><name>ONDREJ TOMAN M.D.</name><affiliations><json:string>University Hospital Brno, Masaryk University, Brno, Czech Republic</json:string></affiliations></json:item><json:item><name>AXEL BAUER M.D.</name><affiliations><json:string>1. Medizinische Klinik, Technische Universität München, Munich, Germany</json:string></affiliations></json:item><json:item><name>GEORG SCHMIDT M.D.</name><affiliations><json:string>1. 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One source of QTc variability is the lack of systematic measurements when electrocardiograms (ECG) with closely matching morphologies are not measured in an exactly corresponding way. The inaccuracy can be eliminated by postprocessing of QT measurements by ECG pattern matching. This study tested the effects of pattern matching in ECG measurements in two populations of healthy subjects (n = 48 + 56) and in a population of patients with advanced Parkinson's disease (n = 130) in whom both day‐time and night‐time data were available. Intrasubject QTc variability was measured by intrasubject standard deviations (SD) of QTc values obtained with manual measurements before and after pattern‐matching measurement alignments. In each subject, QT values (n = 230–320) in one drug‐free long‐term ECG recording were evaluated. The pattern‐matching adjustment of the QT measurement decreased the intrasubject QTc variability from 5.2 ± 1.0 to 4.5 ± 1.0 ms (P < 10−14) from 6.4 ± 1.7 to 5.5 ± 1.6 ms (P < 10−10) from 5.6 ± 1.5 to 4.6 ± 1.4 ms (P < 10−34) and from 6.1 ± 1.9 to 5.0 ± 1.7 ms (P < 10−33), in the two populations of healthy subjects and in the day‐time and night‐time recordings of Parkinson's disease patients, respectively. Hence, morphological pattern adjustment of QT interval measurements improves the quality of the QT data with substantial practical implications. Reductions in intrasubject QTc variability were reproducibly found in different populations and thus the technology might be recommended for every thorough QT/QTc study. Noticeable reductions of necessary study size are likely achievable in this way.</p></abstract><textClass xml:lang="en"><keywords scheme="keyword"><list><head>Keywords</head><item><term>thorough QT/QTc study</term></item><item><term>QTc variability</term></item><item><term>ECG morphology</term></item><item><term>pattern matching</term></item></list></keywords></textClass></profileDesc><revisionDesc><change when="2009-01">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><original>false</original><mimetype>text/plain</mimetype><extension>txt</extension><uri>https://api.istex.fr/document/1558911AA9DECDFD9330F4DFF1E4681506AA655E/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Wiley, elements deleted: body"><istex:xmlDeclaration>version="1.0" encoding="UTF-8" standalone="yes"</istex:xmlDeclaration><istex:document><component version="2.0" type="serialArticle" xml:lang="en"><header><publicationMeta level="product"><publisherInfo><publisherName>Blackwell Publishing Inc</publisherName><publisherLoc>Malden, USA</publisherLoc></publisherInfo><doi origin="wiley" registered="yes">10.1111/(ISSN)1540-8159</doi><issn type="print">0147-8389</issn><issn type="electronic">1540-8159</issn><idGroup><id type="product" value="PACE"></id><id type="publisherDivision" value="ST"></id></idGroup><titleGroup><title type="main" sort="PACING CLINICAL ELECTROPHYSIOLOGY">Pacing and Clinical Electrophysiology</title></titleGroup></publicationMeta><publicationMeta level="part" position="01001"><doi origin="wiley">10.1111/pace.2009.32.issue-1</doi><numberingGroup><numbering type="journalVolume" number="32">32</numbering><numbering type="journalIssue" number="1">1</numbering></numberingGroup><coverDate startDate="2009-01">January 2009</coverDate></publicationMeta><publicationMeta level="unit" type="article" position="17" status="forIssue"><doi origin="wiley">10.1111/j.1540-8159.2009.02185.x</doi><idGroup><id type="unit" value="PACE2185"></id></idGroup><countGroup><count type="pageTotal" number="12"></count></countGroup><titleGroup><title type="tocHeading1"><i>COMPUTER APPLICATION</i></title></titleGroup><copyright>©2009, The Authors. Journal compilation ©2009, Blackwell Publishing, Inc.</copyright><eventGroup><event type="firstOnline" date="2008-12-23"></event><event type="publishedOnlineFinalForm" date="2008-12-23"></event><event type="xmlConverted" agent="Converter:BPG_TO_WML3G version:2.3.2 mode:FullText source:FullText result:FullText" date="2010-03-02"></event><event type="xmlConverted" agent="Converter:WILEY_ML3G_TO_WILEY_ML3GV2 version:3.8.8" date="2014-02-06"></event><event type="xmlConverted" agent="Converter:WML3G_To_WML3G version:4.1.7 mode:FullText,remove_FC" date="2014-11-03"></event></eventGroup><numberingGroup><numbering type="pageFirst" number="119">119</numbering><numbering type="pageLast" number="130">130</numbering></numberingGroup><correspondenceTo>Address for reprints: Marek Malik, Ph.D., M.D., St. Paul's Cardiac Electrophysiology, 16 Verulam Avenue, Purley, Surrey, London CR8 3NQ, United Kingdom. Fax: +44‐20‐8660‐6031; e‐mail: <email>marek.malik@btinternet.com</email></correspondenceTo><objectNameGroup><objectName elementName="appendix">Appendix</objectName></objectNameGroup><linkGroup><link type="toTypesetVersion" href="file:PACE.PACE2185.pdf"></link></linkGroup></publicationMeta><contentMeta><unparsedEditorialHistory>Received August 18, 2008; revised September 25, 2008; accepted October 11, 2008.</unparsedEditorialHistory><countGroup><count type="figureTotal" number="7"></count><count type="tableTotal" number="0"></count><count type="formulaTotal" number="27"></count><count type="referenceTotal" number="19"></count><count type="linksCrossRef" number="40"></count></countGroup><titleGroup><title type="main">Systematic Comparisons of Electrocardiographic Morphology Increase the Precision of QT Interval Measurement</title><title type="shortAuthors">HNATKOVA, ET AL.</title><title type="short">SYSTEMATIC QT INTERVAL MEASUREMENT</title></titleGroup><creators><creator creatorRole="author" xml:id="cr1" affiliationRef="#a1"><personName><givenNames>KATERINA</givenNames><familyName>HNATKOVA</familyName><degrees>Ph.D.</degrees></personName></creator><creator creatorRole="author" xml:id="cr2" affiliationRef="#a2"><personName><givenNames>PETER</givenNames><familyName>SMETANA</familyName><degrees>M.D., Ph.D.</degrees></personName></creator><creator creatorRole="author" xml:id="cr3" affiliationRef="#a3"><personName><givenNames>ONDREJ</givenNames><familyName>TOMAN</familyName><degrees>M.D.</degrees></personName></creator><creator creatorRole="author" xml:id="cr4" affiliationRef="#a4"><personName><givenNames>AXEL</givenNames><familyName>BAUER</familyName><degrees>M.D.</degrees></personName></creator><creator creatorRole="author" xml:id="cr5" affiliationRef="#a4"><personName><givenNames>GEORG</givenNames><familyName>SCHMIDT</familyName><degrees>M.D.</degrees></personName></creator><creator creatorRole="author" xml:id="cr6" affiliationRef="#a1"><personName><givenNames>MAREK</givenNames><familyName>MALIK</familyName><degrees>Ph.D., M.D.</degrees></personName></creator></creators><affiliationGroup><affiliation xml:id="a1" countryCode="GB"><unparsedAffiliation>St. Paul's Cardiac Electrophysiology, London, United Kingdom</unparsedAffiliation></affiliation><affiliation xml:id="a2" countryCode="AT"><unparsedAffiliation>Wilhelminenspital der Stadt Wien, Vienna, Austria</unparsedAffiliation></affiliation><affiliation xml:id="a3" countryCode="CZ"><unparsedAffiliation>University Hospital Brno, Masaryk University, Brno, Czech Republic</unparsedAffiliation></affiliation><affiliation xml:id="a4" countryCode="DE"><unparsedAffiliation>1. Medizinische Klinik, Technische Universität München, Munich, Germany</unparsedAffiliation></affiliation></affiliationGroup><keywordGroup xml:lang="en"><keyword xml:id="k1"><i>thorough QT/QTc study</i></keyword><keyword xml:id="k2"><i>QTc variability</i></keyword><keyword xml:id="k3"><i>ECG morphology</i></keyword><keyword xml:id="k4"><i>pattern matching</i></keyword></keywordGroup><abstractGroup><abstract type="main" xml:lang="en"><p> <i>Decreased intrasubject variability of QTc values is needed to increase the power and reduce the size of the so‐called thorough QT studies. One source of QTc variability is the lack of systematic measurements when electrocardiograms (ECG) with closely matching morphologies are not measured in an exactly corresponding way. The inaccuracy can be eliminated by postprocessing of QT measurements by ECG pattern matching. This study tested the effects of pattern matching in ECG measurements in two populations of healthy subjects (n = 48 + 56) and in a population of patients with advanced Parkinson's disease (n = 130) in whom both day‐time and night‐time data were available. Intrasubject QTc variability was measured by intrasubject standard deviations (SD) of QTc values obtained with manual measurements before and after pattern‐matching measurement alignments. In each subject, QT values (n = 230–320) in one drug‐free long‐term ECG recording were evaluated. The pattern‐matching adjustment of the QT measurement decreased the intrasubject QTc variability from 5.2 ± 1.0 to 4.5 ± 1.0 ms (P < 10<sup>−14</sup>) from 6.4 ± 1.7 to 5.5 ± 1.6 ms (P < 10<sup>−10</sup>) from 5.6 ± 1.5 to 4.6 ± 1.4 ms (P < 10<sup>−34</sup>) and from 6.1 ± 1.9 to 5.0 ± 1.7 ms (P < 10<sup>−33</sup>), in the two populations of healthy subjects and in the day‐time and night‐time recordings of Parkinson's disease patients, respectively. Hence, morphological pattern adjustment of QT interval measurements improves the quality of the QT data with substantial practical implications. Reductions in intrasubject QTc variability were reproducibly found in different populations and thus the technology might be recommended for every thorough QT/QTc study. Noticeable reductions of necessary study size are likely achievable in this way.</i> </p><!-- (PACE 2009; 32:119–130)
</abstractGroup></contentMeta></header></component></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>Systematic Comparisons of Electrocardiographic Morphology Increase the Precision of QT Interval Measurement</title></titleInfo><titleInfo type="abbreviated"><title>SYSTEMATIC QT INTERVAL MEASUREMENT</title></titleInfo><titleInfo type="alternative" contentType="CDATA" lang="en"><title>Systematic Comparisons of Electrocardiographic Morphology Increase the Precision of QT Interval Measurement</title></titleInfo><name type="personal"><namePart type="given">KATERINA</namePart><namePart type="family">HNATKOVA</namePart><namePart type="termsOfAddress">Ph.D.</namePart><affiliation>St. Paul's Cardiac Electrophysiology, London, United Kingdom</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">PETER</namePart><namePart type="family">SMETANA</namePart><namePart type="termsOfAddress">M.D., Ph.D.</namePart><affiliation>Wilhelminenspital der Stadt Wien, Vienna, Austria</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">ONDREJ</namePart><namePart type="family">TOMAN</namePart><namePart type="termsOfAddress">M.D.</namePart><affiliation>University Hospital Brno, Masaryk University, Brno, Czech Republic</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">AXEL</namePart><namePart type="family">BAUER</namePart><namePart type="termsOfAddress">M.D.</namePart><affiliation>1. Medizinische Klinik, Technische Universität München, Munich, Germany</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">GEORG</namePart><namePart type="family">SCHMIDT</namePart><namePart type="termsOfAddress">M.D.</namePart><affiliation>1. Medizinische Klinik, Technische Universität München, Munich, Germany</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">MAREK</namePart><namePart type="family">MALIK</namePart><namePart type="termsOfAddress">Ph.D., M.D.</namePart><affiliation>St. Paul's Cardiac Electrophysiology, London, United Kingdom</affiliation><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="article" displayLabel="article"></genre><originInfo><publisher>Blackwell Publishing Inc</publisher><place><placeTerm type="text">Malden, USA</placeTerm></place><dateIssued encoding="w3cdtf">2009-01</dateIssued><edition>Received August 18, 2008; revised September 25, 2008; accepted October 11, 2008.</edition><copyrightDate encoding="w3cdtf">2009</copyrightDate></originInfo><language><languageTerm type="code" authority="rfc3066">en</languageTerm><languageTerm type="code" authority="iso639-2b">eng</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType><extent unit="figures">7</extent><extent unit="formulas">27</extent><extent unit="references">19</extent></physicalDescription><abstract lang="en">Decreased intrasubject variability of QTc values is needed to increase the power and reduce the size of the so‐called thorough QT studies. One source of QTc variability is the lack of systematic measurements when electrocardiograms (ECG) with closely matching morphologies are not measured in an exactly corresponding way. The inaccuracy can be eliminated by postprocessing of QT measurements by ECG pattern matching. This study tested the effects of pattern matching in ECG measurements in two populations of healthy subjects (n = 48 + 56) and in a population of patients with advanced Parkinson's disease (n = 130) in whom both day‐time and night‐time data were available. Intrasubject QTc variability was measured by intrasubject standard deviations (SD) of QTc values obtained with manual measurements before and after pattern‐matching measurement alignments. In each subject, QT values (n = 230–320) in one drug‐free long‐term ECG recording were evaluated. The pattern‐matching adjustment of the QT measurement decreased the intrasubject QTc variability from 5.2 ± 1.0 to 4.5 ± 1.0 ms (P < 10−14) from 6.4 ± 1.7 to 5.5 ± 1.6 ms (P < 10−10) from 5.6 ± 1.5 to 4.6 ± 1.4 ms (P < 10−34) and from 6.1 ± 1.9 to 5.0 ± 1.7 ms (P < 10−33), in the two populations of healthy subjects and in the day‐time and night‐time recordings of Parkinson's disease patients, respectively. Hence, morphological pattern adjustment of QT interval measurements improves the quality of the QT data with substantial practical implications. Reductions in intrasubject QTc variability were reproducibly found in different populations and thus the technology might be recommended for every thorough QT/QTc study. Noticeable reductions of necessary study size are likely achievable in this way.</abstract><subject lang="en"><genre>Keywords</genre><topic>thorough QT/QTc study</topic><topic>QTc variability</topic><topic>ECG morphology</topic><topic>pattern matching</topic></subject><relatedItem type="host"><titleInfo><title>Pacing and Clinical Electrophysiology</title></titleInfo><genre type="Journal">journal</genre><identifier type="ISSN">0147-8389</identifier><identifier type="eISSN">1540-8159</identifier><identifier type="DOI">10.1111/(ISSN)1540-8159</identifier><identifier type="PublisherID">PACE</identifier><part><date>2009</date><detail type="volume"><caption>vol.</caption><number>32</number></detail><detail type="issue"><caption>no.</caption><number>1</number></detail><extent unit="pages"><start>119</start><end>130</end><total>12</total></extent></part></relatedItem><identifier type="istex">1558911AA9DECDFD9330F4DFF1E4681506AA655E</identifier><identifier type="DOI">10.1111/j.1540-8159.2009.02185.x</identifier><identifier type="ArticleID">PACE2185</identifier><accessCondition type="use and reproduction" contentType="copyright">©2009, The Authors. 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