title: The severity of ventricular arrhythmia correlates with the extent of myocardial sympathetic denervation, but not with myocardial fibrosis extent in chronic Chagas cardiomyopathy : Chagas disease, denervation and arrhythmia.
abstract: To investigate the correlation between the extent of myocardial sympathetic denervation and fibrosis and the presence of degrees of severity of ventricular arrhythmias in chronic Chagas cardiomyopathy (CCC).
  
  
  
  Forty-three CCC patients with left ventricular ejection fraction (LVEF) ≥ 35% were divided into three groups: SVT group-presenting Sustained Ventricular Tachycardia (SVT) (n = 15), NSVT group-exhibiting episodes of non-SVT (NSVT) on 24-h Holter monitoring (n = 11), and Control group-exhibiting neither SVT nor episodes of NSVT (n = 17). The patients underwent SPECT imaging for myocardial sympathetic innervation with123Iodine-MIBG (MIBG) and myocardial perfusion with99mTc-Sestamibi (MIBI) for the evaluation of regional myocardial fibrosis.
  
  
  
  The summed rest perfusion scores were similar in the three groups. The summed difference score between MIBG and MPI images, which evaluated the extent of denervated but viable myocardium, was significantly higher in SVT group (20.0 ± 8.0) as compared with the control group (2.0 ± 5.0, P < .0001) and with the NSVT group (11.0 ± 8.0, P < .05).
  
  
  
  The occurrence of ventricular arrhythmias of different degrees of severity correlates quantitatively with the extent of cardiac sympathetic denervation, but not with the extent of fibrosis, suggesting that myocardial sympathetic denervation plays a major role in triggering ventricular arrhythmia in CCC.
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Leonardo Pippa
authors.initials: LP
authors.lastname: Gadioli
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Carlos Henrique
authors.initials: CH
authors.lastname: Miranda
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Antonio Osvaldo
authors.initials: AO
authors.lastname: Pintya
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Alexandre Baldini
authors.initials: AB
authors.lastname: de Figueiredo
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: André
authors.initials: A
authors.lastname: Schmidt
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Benedito Carlos
authors.initials: BC
authors.lastname: Maciel
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Marin-Neto
authors.affiliation: Division of Cardiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil. msimoes@fmrp.usp.br.
authors.forename: Marcus Vinicius
authors.initials: MV
authors.lastname: Simões
mesh_terms: D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000000981:diagnostic imaging*; D002598:Chagas Cardiomyopathy / Q000000981:diagnostic imaging*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005355:Fibrosis; D006321:Heart / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging; D009206:Myocardium / Q000473:pathology; D010477:Perfusion; D011446:Prospective Studies; D012720:Severity of Illness Index; D013562:Sympathectomy; D013599:Systole; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D017256:Technetium Tc 99m Sestamibi
keywords: Chronic Chagas cardiomyopathy; myocardial fibrosis; myocardial sympathetic denervation; ventricular arrhythmias