title: Determinants of right ventricular muscle mass in idiopathic dilated cardiomyopathy: impact of left ventricular muscle mass and pulmonary hypertension.
abstract: BACKGROUND
  Although chronic pulmonary hypertension and right ventricular (RV) function carry important functional and prognostic implications in idiopathic dilated cardiomyopathy (IDC), little information on RV muscle mass (RVMM) and its determinants has been published.
  
  
  METHODS
  Our study comprised thirty-five consecutive patients with IDC, left ventricular (LV) ejection fraction<40% and NYHA class≥2. Hemodynamic data and parameters on LV and RV geometry were derived from right heart catheterisation and cardiac magnetic resonance imaging.
  
  
  RESULTS
  RVMM was normalized to body size using a common linear, body surface area based approach (RVMMI) and by an allometric index (RVMM-AI) incorporating adjustment for age, height and weight. Stepwise multiple regression analysis revealed that pulmonary artery pressure and left ventricular muscle mass were independent predictors of RVMM-AI. The interventricular mass ratio of RV and LV mass (IVRM) was closely related to RVMM (r=0.79, p<0.001) and total muscle mass (r=0.39, p<0.02). However, there was no significant relationship between LVMM and IVMR (r=0.17, p=0.32).
  
  
  CONCLUSIONS
  Our data suggest that an increase in RV mass in IDC may be explained by two mechanisms: First, as a consequence of the myopathic process itself resulting in a balanced hypertrophy of both ventricles. Second, due to the chamber specific burden of pulmonary artery pressure rise, resulting in unbalanced RV hypertrophy.
authors.affiliation: 1. Department of Cardiology and Angiology, University of Bochum, Germany;
authors.forename: Julia
authors.initials: J
authors.lastname: Vormbrock
authors.affiliation: 1. Department of Cardiology and Angiology, University of Bochum, Germany;
authors.forename: Jeanette
authors.initials: J
authors.lastname: Liebeton
authors.affiliation: 1. Department of Cardiology and Angiology, University of Bochum, Germany;
authors.forename: Sophia
authors.initials: S
authors.lastname: Wirdeier
authors.affiliation: 1. Department of Cardiology and Angiology, University of Bochum, Germany;
authors.forename: Axel
authors.initials: A
authors.lastname: Meissner
authors.affiliation: 1. Department of Cardiology and Angiology, University of Bochum, Germany;
authors.forename: Thomas
authors.initials: T
authors.lastname: Butz
authors.affiliation: 1. Department of Cardiology and Angiology, University of Bochum, Germany;
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Trappe
authors.affiliation: 2. Department of Cardiology, Johanniter-Krankenhaus, Duisburg, Germany.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Plehn
mesh_terms: D000328:Adult; D000368:Aged; D006328:Cardiac Catheterization / Q000379:methods; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000000981:diagnostic imaging / Q000473:pathology; D011859:Radiography
keywords: Right ventricular muscle mass; heart failure; myocardial hypertrophy.