<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>2954-3835</journal-id>
<journal-title><![CDATA[Cardiovascular and metabolic science]]></journal-title>
<abbrev-journal-title><![CDATA[Cardiovasc. metab. sci]]></abbrev-journal-title>
<issn>2954-3835</issn>
<publisher>
<publisher-name><![CDATA[Asociación Nacional de Cardiólogos de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2954-38352023000100008</article-id>
<article-id pub-id-type="doi">10.35366/110246</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Echocardiographic and electrocardiographic factors associated with non-response to cardiac resynchronization therapy]]></article-title>
<article-title xml:lang="es"><![CDATA[Factores ecocardiográficos y electrocardiográficos asociados con la no respuesta a la terapia de resincronización cardiaca]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Villanueva-Balandrán]]></surname>
<given-names><![CDATA[Araceli]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Aldana-Varela]]></surname>
<given-names><![CDATA[Oswaldo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hernández-Mercado]]></surname>
<given-names><![CDATA[Marco Antonio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,ISSEMyM, «Lic. Arturo Montiel Rojas» Toluca Medical Center ]]></institution>
<addr-line><![CDATA[State of México ]]></addr-line>
<country>México</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,ISSEMyM, «Lic. Arturo Montiel Rojas» Department of the Toluca Medical Center ]]></institution>
<addr-line><![CDATA[State of Mexico ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>03</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>03</month>
<year>2023</year>
</pub-date>
<volume>34</volume>
<numero>1</numero>
<fpage>8</fpage>
<lpage>12</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2954-38352023000100008&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2954-38352023000100008&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2954-38352023000100008&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract:  Introduction:  Heart Failure (HF) is a public health problem in Mexico and worldwide. It is one of the most frequent causes of hospitalization and death in the cardiology and internal medicine departments. Cardiac Resynchronization Therapy (CRT) has been an effective treatment for selected patients with HF. However, even in patients with class I recommendations, the rate of non-response is up to 30%, which makes it necessary to identify predictors of non-response.  Objective:  to find predictors of non-response to CRT.  Material and methods:  the electrocardiographic and echocardiographic features of patients who received CRT at ISSEMyM Medical Center of Toluca (IMCT) were analyzed between June 1st 2003, and June 1st 2019. We looked for an association between these features and the response or non-response to CRT one year after the implantation. A sample of 24 patients with a class I recommendation for CRT were studied; a Multivariate logistic regression analysis was performed to identify predictors of non-response.  Results:  62.5% of the patients with a Left Ventricle End-Diastolic Diameter (LVEDD) &#8805; 77 mm were non-responders (p = 0.003); 75% of the patients with fragmented QRS in the electrocardiogram previous to the CRT were non-responders, although this last result with a non-statistically significant p (0.083).  Conclusions:  the LVEDD &#8805; 77 strongly predicts non-response to CRT. As for the fragmented QRS pattern, even when 75% of patients had it were non-responders, a bigger sample might be required to find statistical significance.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen:  Introducción:  la Insuficiencia Cardiaca (IC) es un problema de salud pública en México y a nivel mundial, es una de las causas más frecuentes de hospitalización y de muerte en los servicios de cardiología y medicina interna. La Terapia de Resincronización Cardiaca (TRC) ha sido un tratamiento efectivo en pacientes seleccionados con IC. Sin embargo, aun en los pacientes con recomendación clase I, la tasa de no respondedores es de hasta 30%, por lo que es necesario identificar predictores de no respuesta.  Objetivos:  encontrar predictores de no respuesta a la terapia de resincronización cardiaca.  Material y métodos:  se revisaron las características electrocardiográficas y ecocardiográficas en pacientes que recibieron TRC en el Centro Médico ISSEMyM Toluca entre el 1o de junio de 2003 y el 1o de junio de 2019. Se buscó la asociación entre estos factores y la respuesta o no respuesta a un año del implante. Se analizó una muestra de 24 pacientes con recomendación clase I para TRC. Se utilizó análisis de regresión logística multivariable para identificar predictores de no respuesta.  Resultados:  el 62.5% de los pacientes que tenían un Diámetro Telediastólico del Ventrículo Izquierdo (DTVI) &#8805; 77 mm fueron no respondedores (p = 0.003); 75% de los pacientes con patrón fragmentado del QRS en el electrocardiograma fueron no respondedores, aunque este último resultado tuvo una p estadísticamente no significativa (0.083).  Conclusiones:  el DTVI &#8805; a 77 mm es un fuerte predictor de no respuesta a la TRC. En cuanto al patrón fragmentado del QRS, a pesar de que 75% no respondió, podría ser necesaria una muestra de pacientes más grande para encontrar significancia estadística.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[cardiac resynchronization therapy]]></kwd>
<kwd lng="en"><![CDATA[heart failure]]></kwd>
<kwd lng="en"><![CDATA[fragmented QRS]]></kwd>
<kwd lng="en"><![CDATA[dilated left ventricle]]></kwd>
<kwd lng="es"><![CDATA[terapia de resincronización cardiaca]]></kwd>
<kwd lng="es"><![CDATA[insuficiencia cardiaca]]></kwd>
<kwd lng="es"><![CDATA[QRS fragmentado]]></kwd>
<kwd lng="es"><![CDATA[ventrículo izquierdo dilatado]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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