title: Skeletal myoblast sheet transplantation improves the diastolic function of a pressure-overloaded right heart.
abstract: OBJECTIVE
  The development of right ventricular dysfunction has become a common problem after surgical repair of complex congenital heart disease. A recent study reported that tissue-engineered skeletal myoblast sheet transplantation improves left ventricular function in patients with dilated and ischemic cardiomyopathy. Therefore myoblast sheet transplantation might also improve ventricular performance in a rat model of a pressure-overloaded right ventricle.
  
  
  METHODS
  Seven-week-old male Lewis rats underwent pulmonary artery banding. Four weeks after pulmonary artery banding, myoblast sheet transplantation to the right ventricle was performed in the myoblast sheet transplantation group (n = 20), whereas a sham operation was performed in the sham group (n = 20).
  
  
  RESULTS
  Four weeks after performing the procedure, a hemodynamic assessment with a pressure-volume loop showed a compensatory increase in systolic function in both groups. However, only the myoblast sheet transplantation group showed a significant improvement in the diastolic function: end-diastolic pressure (sham vs myoblast sheet transplantation, 10.3 +/- 3.1 vs 5.0 +/- 3.7 mm Hg; P < .001), time constant of isovolumic relaxation (11.1 +/- 2.5 vs 7.6 +/- 1.2 ms, P < .001), and end-diastolic pressure-volume relationship (16.1 +/- 4.5 vs 7.6 +/- 2.4/mL, P < .005). The right ventricular weight and cell size similarly increased in both groups. A histologic assessment demonstrated significantly suppressed ventricular fibrosis and increased capillary density in the myoblast sheet transplantation group in comparison with those in the sham group. Reverse transcription-polymerase chain reaction demonstrated an increased myocardial gene expression of hepatocyte growth factor and vascular endothelial growth factor in the myoblast sheet transplantation group but not in the sham group.
  
  
  CONCLUSIONS
  Skeletal myoblast sheet transplantation improved the diastolic dysfunction and suppressed ventricular fibrosis with increased capillary density in a rat model of a pressure-overloaded right ventricle. This method might become a novel strategy for the myocardial regeneration of right ventricular failure in patients with congenital heart disease.
authors.affiliation: Department of Cardiovascular Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Takaya
authors.initials: T
authors.lastname: Hoashi
authors.forename: Goro
authors.initials: G
authors.lastname: Matsumiya
authors.forename: Shigeru
authors.initials: S
authors.lastname: Miyagawa
authors.forename: Hajime
authors.initials: H
authors.lastname: Ichikawa
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ueno
authors.forename: Masamichi
authors.initials: M
authors.lastname: Ono
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Saito
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Shimizu
authors.forename: Teruo
authors.initials: T
authors.lastname: Okano
authors.forename: Naomasa
authors.initials: N
authors.lastname: Kawaguchi
authors.forename: Nariaki
authors.initials: N
authors.lastname: Matsuura
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Sawa
mesh_terms: D000818:Animals; D003971:Diastole; D006352:Heart Ventricles / Q000473:pathology / Q000601:surgery*; D006439:Hemodynamics; D008297:Male; D032448:Myoblasts, Skeletal / Q000637:transplantation*; D051381:Rats; D011917:Rats, Inbred Lew; D023822:Tissue Engineering; D018497:Ventricular Dysfunction, Right / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D016278:Ventricular Function, Right; D017725:Ventricular Pressure