Thrombogenicity of angiographic catheters.

A radioimmunoassay for measurement of canine fibrinopeptide A, which provides a quantitative index of thrombin action on fibrinogen, has been applied to measurements of the thrombogenicity of five angiographic catheters commercially available and presently in clinical use. Examples of thin-walled polyethylene, wired polyethylene, Teflon, polyurethane, and woven Dacron catheters were characterized in terms of chemical composition, surface physiochemical properties, and their procoagulant activities assessed in vivo in an experimental system that closely simulated their actual clinical use. The catheters could be divided into three groups based on the fibrinopeptide A levels generated during a 30-minute test period as well as on the surface deposition of fibrin and platelets, as judged by scanning electron microscopy. Group I (thin-walled polyethylene) showed no increase in fibrinopeptide A levels over control and no fibrin deposition, but moderate platelet deposition. Group II (wired polyethylene and Teflon) showed moderate increases in fibrinopeptide A levels, with moderate fibrin and platelet deposition. Group HI catheters (polyurethane and woven Dacron) showed marked fibrinopeptide A production and extensive fibrin deposition that contained variable numbers of platelet aggregates. We conclude that fibrinopeptide A levels correlate well with surface fibrin deposition and therefore are useful to assess the degree to which different catheters stimulate fibrin production. It may be that the procoagulant effects of these catheters are mediated through the textural and physiochemical properties of the surfaces of these devices, which are in contact with blood.