Alterações contráteis segmentares e sua associação com arritmias ventriculares complexas, em pacientes chagásicos com eletrocardiograma normal ou borderline

Abstract

INTRODUÇÃO: Morte súbita representa a principal causa de óbito em chagásicos. Eventos fatais em pacientes saudáveis, com anormalidades contráteis, foram documentados. O objetivo deste trabalho é determinar a associação entre alteração contrátil e arritmias ventriculares complexas em pacientes chagásicos, classe funcional I, eletrocardiograma normal ou borderline e função ventricular preservada. MÉTODOS: Quarenta e nove pacientes com doença de Chagas e eletrocardiograma normal ou borderline realizaram ecocardiograma, teste ergométrico e Holter. Avaliou-se a contratilidade global e segmentar dos ventrículos e a presença de arritmias ventriculares complexas induzidas no esforço e espontâneas, respectivamente. A análise estatística foi feita pelo modelo Log-Linear geral. RESULTADOS: Idade média de 56 anos; 55% mulheres. Alterações contráteis segmentares em 24,5% dos pacientes; 12% dos Holter e 18% dos testes ergométricos positivos. Houve associação entre arritmia e alteração segmentar condicionada à presença da disfunção sistólica leve do ventrículo esquerdo. CONCLUSÕES: Alterações contráteis, na presença de disfunção global leve, indicam pacientes sob maior risco de arritmias complexas.

Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

“…Patients with CD and normal electrocardiogram (ECG) are known to have survival rate similar to that of the general population, and initial studies have shown that those with CD, segmental wall motion abnormality and preserved LVEF have worse prognosis 5,6 .…”

Clinical and Echocardiographic Predictors of Mortality in Chagasic Cardiomyopathy - Systematic Review

“…As for the addressed topics, 10 articles considered prognostic factors of mortality and risk of disease progression using echocardiography 13,19,22,23,26,28,30,32,35,36 , five studies assessed left ventricular ejection fraction (LVEF) 20,25,29,34,39 , alone or together with prognostic factors, seven articles assessed systolic and diastolic ventricular function with tissue Doppler 15-17,27,33,36,40 , five assessed concentrations of brain natriuretic peptide (BNP) 21,24,29,31,37 , one study assessed the prognostic value of troponin concentrations 18 , one study evaluated ventricular dyssynchrony 38 , two studies assessed cardiac dysautonomia 14,41 , two studies used two-dimensional echocardiography to assess ventricular deformation (strain, strain rate and twisting) 33,42 and one study addressed the proinflammatory and prothrombotic factors in Chagas disease 43 .…”

“…Studies with group comparison 13-18,21,24,26,27,31,33,35,37,40,41 aimed to evaluate the clinical, hemodynamic and evolution aspects of Chagas cardiomyopathy, while those aimed to identifying morphological and functional characteristics related to prognosis and mortality did not employ this methodology 19,20,22,23,25,28-30,32,34,36,38,39 . The identification of the predominance of publications aimed to investigate adult patients (between the third and fourth decades of life), when compared to those involving adolescents, seems justified by the physiopathology of the disease.…”

“…This fact, which persists a century after the first description of the disease, has motivated many studies on prognostic factors of mortality and risk of disease progression, among which 10 were included in this review 10,17,19,20,23,25,27,29,31,37 . All these studies recognize the importance of identifying the chagasic etiology of heart failure, given its destructive and overwhelming role due to incessant myocarditis, caused by extensive myocardial fibrosis, as well as being responsible for complex ventricular arrhythmias, which may explain poorer prognosis of chagasic patients when compared to patients with primary dilated cardiomyopathy 13,34 .…”