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Introduction: 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., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: Thromboembolic events have been observed in heart failure (HF) patients supported by long-term mechanical circulatory support (MCS) devices. It has been hypothesized that these adverse events may be the result of platelet activation associated with high rotational speeds common to axial flow pumps. In this study, markers of platelet activation were investigated in HF patients supported by a HeartMate II left ventricular assist device (LVAD)., Methods: The study group consisted of 34 HF patients supported by a HeartMate II axial flow LVAD implanted for destination therapy (DT). This patient population was 94% male (31 M, 3 F), supported by LVAD for 30 to 723 days (average 268 days), and with an anticoagulation regimen of Coumadin (0-8 mg daily dose) and aspirin (0-325 mg daily dose). Platelet adhesion markers (soluble P-selectin and solube CD40 ligand), platelet count (PC), hematocrit (Hct), and creatinine (Cr) were measured., Results: The soluble P-selectin marker was within normal platelet activity limits for all end points. The soluble CD40 ligand marker indicated platelet inactivity for all end points. Despite high shear stresses associated with a high-speed axial flow pump, the HeartMate II had no discernable effect on platelet activation. Current clinical doses of aspirin also appear to have little effect on platelet activation. Platelet count, hematocrit, and creatinine were normal in these patients over duration of support., Conclusions: There were no discernable changes in platelet activation markers soluble P-selectin and soluble CD40 ligand in HF patients support by HeartMate II LVAD independently of length of support, anti-platelet, and anti-coagulation regimens.