title: Transmyocardial coil implants: a novel approach to transmyocardial revascularization.
abstract: BACKGROUND
  Transmyocardial laser revascularization (TMLR) has potential benefit for patients with end-stage coronary artery disease and intractable angina not amenable to conventional revascularization techniques. Neovascularization has been proposed to occur around the laser channels. Our aim was to determine the feasibility of a novel nonlaser myocardial revascularization technique and its effect on angiogenesis in a nonischemic porcine model.
  
  
  METHODS
  In the first phase, six transmyocardial stainless steel coil implants (TMI) were deployed to the lateral wall of the left ventricle in each of 6 pigs. The animals were sacrificed at 8 and 12 weeks, with a single animal dying prematurely at 4 weeks, and the myocardium was assessed for new vessel growth. In the second phase, 8 implants were deployed in each of 12 pigs with regular fluoroscopic follow-up until sacrifice at 2 weeks to assess implant stability.
  
  
  RESULTS
  The deployment procedure was safe and feasible with no complications evident. A significant increase in new vessels at implant sites with 5.43 +/- 3.67, 4.97 +/- 2.44, and 3.57 +/- 2.29 seen per high power field at 12, 8, and 4 weeks, respectively, compared to 1.00 +/- 1.06 (p < 0.0001) in control myocardium. There was no evidence of implant migration in Phase 2.
  
  
  CONCLUSIONS
  TMIs can feasibly be deployed in the nonischemic pig model with a high success rate. The presence of angiogenesis at the implant site and the maintenance of this reaction for 3 months implies that TMI may offer an alternative to TMLR while providing a platform for delivery of angiogenic factors.
authors.affiliation: Department of Medicine, Montreal Heart Institute, Quebec, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Meerkin
authors.forename: Michel
authors.initials: M
authors.lastname: Pellerin
authors.forename: H Thomas
authors.initials: HT
authors.lastname: Aretz
authors.forename: Patrice
authors.initials: P
authors.lastname: Paiement
authors.forename: Stuart L
authors.initials: SL
authors.lastname: Houser
authors.forename: Raoul
authors.initials: R
authors.lastname: Bonan
mesh_terms: D000818:Animals; D004867:Equipment Design; D005240:Feasibility Studies; D009204:Myocardial Revascularization / Q000295:instrumentation*; D009206:Myocardium / Q000473:pathology; D013552:Swine