title: Is autonomic function associated with left ventricular systolic function in Chagas heart disease patients undergoing treatment for heart failure?
abstract: BACKGROUND
  The association between cardiac autonomic and left ventricular (LV) dysfunction in Chagas disease (ChD) is controversial.
  
  
  METHODS
  A standardized protocol that includes the Valsalva maneuver, a respiratory sinus arrhythmia (RSA) test, and an echocardiographic examination was used. Spearman correlation coefficients (rho) were used to investigate associations.
  
  
  RESULTS
  The study population consisted of 118 ChD patients undergoing current medical treatment, with an average LV ejection fraction of 51.4±2.6%. The LV ejection fraction and diastolic dimension were correlated with the Valsalva index (rho=0.358, p<0.001 and rho=-0.266, p=0.004, respectively) and the RSA (rho=0.391, p<0.001 and rho=-0.311, p<0.001, respectively).
  
  
  CONCLUSIONS
  The impairment of LV function is directly associated with a reduction of cardiac autonomic modulation in ChD.
authors.affiliation: Faculdade de Medicina e Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, BRAZIL.
authors.forename: Lotte
authors.initials: L
authors.lastname: Raadschilders
authors.affiliation: Faculdade de Medicina e Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, BRAZIL.
authors.forename: Manoel Otavio da Costa
authors.initials: MO
authors.lastname: Rocha
authors.affiliation: Faculdade de Medicina e Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, BRAZIL.
authors.forename: Lidiane
authors.initials: L
authors.lastname: Sousa
authors.affiliation: Department of Medical Microbiology en Infectious Diseases, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Nouwen
authors.affiliation: Faculdade de Medicina e Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, BRAZIL.
authors.forename: Antonio Luiz
authors.initials: AL
authors.lastname: Ribeiro
mesh_terms: D001341:Autonomic Nervous System / Q000503:physiopathology*; D002598:Chagas Cardiomyopathy / Q000150:complications / Q000503:physiopathology*; D004452:Echocardiography; D006333:Heart Failure / Q000188:drug therapy* / Q000209:etiology; D006801:Humans; D014636:Valsalva Maneuver; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology*