title: Skeletal muscle abnormalities in pulmonary arterial hypertension.
abstract: BACKGROUND
  Pulmonary arterial hypertension is a progressive disease that is characterized by dyspnea and exercise intolerance. Impairment in skeletal muscle has recently been described in PAH, although the degree to which this impairment is solely determined by the hemodynamic profile remains uncertain. The aim of this study was to verify the association of structural and functional skeletal muscle characteristics with maximum exercise in PAH.
  
  
  METHODS
  The exercise capacity, body composition, CT area of limb muscle, quality of life, quadriceps biopsy and hemodynamics of 16 PAH patients were compared with those of 10 controls.
  
  
  RESULTS
  PAH patients had a significantly poorer quality of life, reduced percentage of lean body mass, reduced respiratory muscle strength, reduced resistance and strength of quadriceps and increased functional limitation at 6MWT and CPET. VO2 max was correlated with muscular variables and cardiac output. Bivariate linear regression models showed that the association between muscular structural and functional variables remained significant even after correcting for cardiac output.
  
  
  CONCLUSIONS
  Our study showed the coexistence of ventilatory and quadriceps weakness in face of exercise intolerance in the same group of PAH patients. More interestingly, it is the first time that the independent association between muscular pattern and maximum exercise capacity is evidenced in PAH, independently of cardiac index highlighting the importance of considering rehabilitation in the treatment strategy for PAH.
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Breda
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Andre Luis
authors.initials: AL
authors.lastname: Pereira de Albuquerque
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Carlos
authors.initials: C
authors.lastname: Jardim
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Luciana Kato
authors.initials: LK
authors.lastname: Morinaga
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Milena Mako
authors.initials: MM
authors.lastname: Suesada
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Caio Julio Cesar
authors.initials: CJ
authors.lastname: Fernandes
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Dias
authors.affiliation: Radiology Department, University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Rafael Burgomeister
authors.initials: RB
authors.lastname: Lourenço
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Joao Marcos
authors.initials: JM
authors.lastname: Salge
authors.affiliation: Pulmonary Department, Heart Institute University of São Paulo Medical School, Sao Paulo, Brazil.
authors.forename: Rogerio
authors.initials: R
authors.lastname: Souza
mesh_terms: D000328:Adult; D001706:Biopsy; D001823:Body Composition; D016022:Case-Control Studies; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology*; D011788:Quality of Life