title: Evaluation of new Forcefield technology: reducing platelet adhesion and cell coverage of pyrolytic carbon surfaces.
abstract: BACKGROUND
  Platelet adhesion and activation are a significant source of clinical complications. Preventing foreign surface-platelet interaction may improve biocompatibility of implantable medical devices. This study evaluated efficacy of novel technique for electrically modifying surface of conductive biomaterial and attaching blood components to prevent thrombogenesis. Specifically, this new surface modification technology, Forcefield (ATS Medical, Inc, Minneapolis, Minn), was designed to prevent platelet adhesion on pyrolytic carbon. A modulated low-voltage current is directly applied to pyrolytic carbon surfaces to stimulate adherence of a layer of charged proteins from circulating blood components that is resistive to platelet deposition.
  
  
  METHODS
  Feasibility of Forcefield technology was tested in line with cardiopulmonary bypass circuit in patients undergoing standard cardiac surgery (n = 6). Forcefield treatment was applied to segment of pyrolytic carbon with 15 minutes (n = 3) and 30 minutes (n = 3) of electrically stimulated exposure time, and resulting segments were compared with untreated pyrolytic carbon segment. Platelet adhesion confluence was then quantified by scanning electron microscopy.
  
  
  RESULTS
  Confluence of the Forcefield-treated pyrolytic carbon segments (3.3% ± 2.2%) was significantly reduced relative to untreated pyrolytic carbon control segments (81.7% ± 24%, P < .001). There were no discernible differences in cell confluence with Forcefield-treated segments as function of exposure time (15 or 30 minutes).
  
  
  CONCLUSIONS
  Forcefield technology may enable modification of pyrolytic carbon surfaces to prevent platelet adhesion and thrombogenesis of implanted medical devices, including heart valves, stents, catheters, and ventricular assist devices, and may eliminate the need for anticoagulant and antiplatelet therapies.
authors.affiliation: Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Louisville, Louisville, KY, USA. mark.slaughter@louisville.edu
authors.forename: Mark S
authors.initials: MS
authors.lastname: Slaughter
authors.forename: Brian
authors.initials: B
authors.lastname: Pederson
authors.forename: Joel D
authors.initials: JD
authors.lastname: Graham
authors.forename: Michael A
authors.initials: MA
authors.lastname: Sobieski
authors.forename: Steven C
authors.initials: SC
authors.lastname: Koenig
mesh_terms: D000368:Aged; D002244:Carbon; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000295:instrumentation*; D020099:Coated Materials, Biocompatible / Q000009:adverse effects; D004553:Electric Conductivity; D004867:Equipment Design; D005240:Feasibility Studies; D006801:Humans; D007087:Illinois; D008297:Male; D008855:Microscopy, Electron, Scanning; D010865:Pilot Projects; D010973:Platelet Adhesiveness; D013499:Surface Properties; D013673:Technology Assessment, Biomedical; D013927:Thrombosis / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors
chemical_list: D020099:Coated Materials, Biocompatible; C009139:pyrolytic carbon; D002244:Carbon