Nascimento Bruno Ramos, Araújo Christiano Gonçalves, Rocha Manoel Otávio Costa, Domingues José Darlan Pinheiro, Rodrigues Aline Braga, Barros Márcio Vinicius Lins, Ribeiro Antonio Luiz Pinho
Serviço de Cardiologia e Cirurgia Cardiovascular, Hospital das Clínicas da Universidade Federal de Minas Gerais, 30130-100, Belo Horizonte, Brazil.
J Electrocardiol. 2012 Jan-Feb;45(1):43-8. doi: 10.1016/j.jelectrocard.2011.04.011. Epub 2011 Jun 24.
The meaning of electrocardiographic changes appearing during the clinical follow-up of Chagas disease (ChD) is unknown. In this study, a patient cohort with ChD was followed to describe the electrocardiographic changes that may make it possible to identify patients whose left ventricular function has deteriorated.
The study sample consisted of a prospective cohort followed since 1998 to 1999, involving 220 patients aged 15 to 55 years, 30 controls, and 190 with ChD, without other comorbidities. The group was reexamined between 2004 and 2006, and new electrocardiograms were obtained for 153 patients, 25 (83%) of 30 in the control group and 128 (72%) of 177 in the ChD group. Electrocardiographic variables associated with a significant decrease in ejection fraction (5% or more) were identified.
A significant decrease in ejection fraction was observed in 21 patients in the ChD group (18.7%) but in none of the non-ChD group (P = .024). Only the presence of a new electrocardiographic abnormality and an increase in QRS duration correlated with a decrease in an ejection fraction of 5% or more. QRS duration was correlated with both an increase in left ventricle diastolic diameter and a deterioration in the ejection fraction (r(s) = 0.225, P = .017, and r(s) = -0.300, P < .001). A QRS increase of 5 milliseconds had 77.8% sensitivity and 62.2% specificity for identifying patients with significant decrease in ejection fraction.
The increase in the duration of the QRS complex and the appearance of new electrocardiographic alterations may help in identifying patients with a significant decrease (of 5% or more) in left ventricle ejection fraction.
恰加斯病（ChD）临床随访期间出现的心电图变化的意义尚不清楚。在本研究中，对一组恰加斯病患者进行随访，以描述可能有助于识别左心室功能恶化患者的心电图变化。
研究样本包括自1998年至1999年以来随访的一个前瞻性队列，涉及220名年龄在15至55岁之间的患者，30名对照者和190名恰加斯病患者，无其他合并症。该组在2004年至2006年期间重新进行检查，为153名患者获取了新的心电图，对照组30名中的25名（83%）以及恰加斯病组177名中的128名（72%）。确定了与射血分数显著降低（5%或更多）相关的心电图变量。
恰加斯病组中有21名患者（18.7%）观察到射血分数显著降低，而非恰加斯病组中无一例出现这种情况（P = 0.024）。只有新出现的心电图异常和QRS波时限增加与射血分数降低5%或更多相关。QRS波时限与左心室舒张直径增加以及射血分数恶化均相关（r(s) = 0.225，P = 0.017，r(s) = -0.300，P < 0.001）。QRS波时限增加5毫秒对识别射血分数显著降低的患者具有77.8%的敏感性和62.2%的特异性。
QRS波群时限增加和新的心电图改变的出现可能有助于识别左心室射血分数显著降低（5%或更多）的患者。
