title: Growth factors improve latissimus dorsi muscle vascularization and trophicity after cardiomyoplasty.
abstract: BACKGROUND
  Dynamic cardiomyoplasty consists of wrapping the electrostimulated latissimus dorsi muscle (LDM) around the failed heart. Partial ischemia followed by atrophy of the middle and distal part of the LDM were observed in 30% of clinical cases after LDM flap elevation from its origin. In the current study, we hypothesized that local administration of growth factors at the LDM/epicardial interface could improve muscle vascularization and trophicity.
  
  
  METHODS
  In 24 sheep, dynamic cardiomyoplasty was performed using the left LDM. A multiperforated catheter was positioned at the LDM/epicardial interface for a weekly administration, during a 1-month period, of the following factors: basic fibroblast growth factor (bFGF, n = 6), vascular endothelial growth factor (VEGF, n = 6), and regenerating agent (RGTA, n = 6). Six sheep injected with phosphate-buffered saline (used for dilution of the growth factors) were used as a control group. At 3 months, angiographic, histologic, and histomorphometric studies were performed.
  
  
  RESULTS
  Angiographic studies of the animals treated with growth factors demonstrated hypervascularization due to the development of new vessels. Histomorphometric and histologic studies showed a significant increase in the number of capillaries and arterioles (100 fields/muscle) in the groups treated with bFGF (443.0 +/- 101.2, p < 0.01), RGTA (293.2 +/- 29.3, p < 0.05), and VEGF (246.5 +/- 45.9, p < 0.05), as compared with the control group (81.5 +/- 11.4). A significantly lower atrophy score was observed in the groups treated with bFGF (1.4 +/- 0.18, p < 0.05), RGTA (1.59 +/- 0.17, p < 0.05), and VEGF (1.96 +/- 0.14, NS), as compared with the control group (2.48 +/- 0.16).
  
  
  CONCLUSIONS
  Local administration at the heart/muscle interface of growth factors increases muscle vascularization and avoids muscle atrophy in an experimental cardiomyoplasty model, both of which are advantageous to the contracting LDM. The local growth factors delivery system used in this study appears efficient, easy to implant, and manipulate and safe.
authors.affiliation: Department of Cardiovascular Surgery, Broussais Hospital, Paris, France.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Zakine
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Martinod
authors.forename: Paul
authors.initials: P
authors.lastname: Fornes
authors.forename: Marc
authors.initials: M
authors.lastname: Sapoval
authors.forename: Denis
authors.initials: D
authors.lastname: Barritault
authors.forename: Alain F
authors.initials: AF
authors.lastname: Carpentier
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Chachques
mesh_terms: D000818:Animals; D018421:Cardiomyoplasty; D003911:Dextrans / Q000008:administration & dosage / Q000494:pharmacology*; D016228:Endothelial Growth Factors / Q000008:administration & dosage / Q000494:pharmacology*; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage / Q000494:pharmacology*; D006133:Growth Substances / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology*; D036341:Intercellular Signaling Peptides and Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D008222:Lymphokines / Q000008:administration & dosage / Q000494:pharmacology*; D023421:Models, Animal; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D012756:Sheep; D019739:Skeletal Muscle Ventricle / Q000098:blood supply* / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
chemical_list: D003911:Dextrans; D016228:Endothelial Growth Factors; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D008222:Lymphokines; C104129:RGTA11; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D016222:Fibroblast Growth Factor 2