Abstract: A method and medicament for treating and preventing platelet activation or thrombosis in the presence of heparin-and platelet factor 4-complex reactive antibodies using a 2-O desulfated heparin with an average degree of sulfation of 0.6 sulfate groups per monosaccharide or greater and an average molecular weight or 2.4 kD or greater. The medicament preferably is administered intravenously, by aerosolization or orally. Preferably, the 2-O desulfated heparin medicament includes a physiologically acceptable carrier which may be selected from the group consisting of physiologically buffered saline, normal saline, and distilled water. Additionally provided is a method of synthesizing 2-O desulfated heparin.

Abstract: A catheter for preventing the stenosis or restenosis of a body vessel or cavity, e.g., a blood vessel, whereby a membrane may be applied to the inner surface of the vessel or cavity. The inventive catheter tip utilizes (a) two inflatable chamber balloons which, when inflated, isolate a portion of the vessel or cavity for treatment and (b) an inflatable treatment balloon disposed between the two chamber balloons which provides a means for treating the isolated site. The invention permits the flow of body fluid, e.g., blood, to the distal side of the catheter tip while the balloons are in an inflated state. The invention further permits the rinsing and flushing of fluids or medications of an isolated longitudinal portion of the vessel or cavity prior to and after an application of a membrane located on the treatment balloon.