title: Development of a biological ventricular assist device: preliminary data from a small animal model.
abstract: BACKGROUND
  Engineered heart tissue (EHT) can be generated from cardiomyocytes and extracellular matrix proteins and used to repair local heart muscle defects in vivo. Here, we hypothesized that pouch-like heart muscle constructs can be generated by using a novel EHT-casting technology and applied as heart-embracing cardiac grafts in vivo.
  
  
  RESULTS
  Pouch-like EHTs (inner/outer diameter: 10/12 mm) can be generated mainly from neonatal rat heart cells, collagen type I, and serum containing culture medium. They contain a dense network of connexin 43 interconnected cardiomyocytes and an endo-/epicardial surface lining composed of prolylhydroxylase positive cells. Pouch-like EHTs beat spontaneously and show contractile properties of native heart muscle including positive inotropic responses to calcium and isoprenaline. First implantation studies indicate that pouch-like EHTs can be slipped over uninjured adult rat hearts to completely cover the left and right ventricles. Fourteen days after implantation, EHT-grafts stably covered the epicardial surface of the respective hearts. Engrafted EHTs were composed of matrix and differentiated cardiac muscle as well as newly formed vessels which were partly donor-derived.
  
  
  CONCLUSIONS
  Pouch-like EHTs can be generated with structural and functional properties of native myocardium. Implantation studies demonstrated their applicability as cardiac muscle grafts, setting the stage for an evaluation of EHT-pouches as biological ventricular assist devices in vivo.
authors.affiliation: Institute of Experimental and Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
authors.forename: Yalin
authors.initials: Y
authors.lastname: Yildirim
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Naito
authors.forename: Michael
authors.initials: M
authors.lastname: Didié
authors.forename: Bijoy Chandapillai
authors.initials: BC
authors.lastname: Karikkineth
authors.forename: Daniel
authors.initials: D
authors.lastname: Biermann
authors.forename: Thomas
authors.initials: T
authors.lastname: Eschenhagen
authors.forename: Wolfram-Hubertus
authors.initials: WH
authors.lastname: Zimmermann
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D021522:Bioartificial Organs; D016027:Heart Transplantation / Q000379:methods*; D006352:Heart Ventricles / Q000166:cytology / Q000254:growth & development / Q000637:transplantation; D006353:Heart-Assist Devices / Q000469:parasitology; D009200:Myocardial Contraction / Q000502:physiology; D032383:Myocytes, Cardiac / Q000637:transplantation; D009924:Organ Culture Techniques / Q000379:methods; D010496:Pericardium / Q000166:cytology / Q000254:growth & development; D051381:Rats; D017208:Rats, Wistar; D023822:Tissue Engineering / Q000379:methods*