Analysis of anticoagulant and antiplatelet capacity of Nitinol-Polypyrrole devices doped with drugs.

SANDOVAL MJ; FLAMINI DO; MASSHEIMER VL; VALLE MI; SAIDMAN SB

Mar del Plata

Congreso; LXI Reunión Anual Científica de la Sociedad Argentina de Investigación Clínica; 2016

Sociedad Argentina de Investigación Clínica

Hemostasis plays an active role in atherosclerotic disease and arterial stenosis. Nitinol (NiTi) is used in several biomedical applications such as stents. Despite its biocompatibility, elasticity and corrosion resistance, some Ni2+ and Ti2+ ions may be released, resulting in local and systemic unwanted effects. The use of polypyrrole (PPy) coating, protects from ion release and, allows doping with drugs designed such as heparin (Hep) and sodium salicylate (NaSa). This work evaluates the effect on blood coagulation and platelet aggregation (PA) of NiTi-PPy devices (slices of 1cm2) doped with Hep (0.2; 0.3; 0.4 g/L), NaSa (0.1 and 0.5 M) or the combination of NaSa plus Hep (0.5M + 0.2 g/L). The slices were incubated 35 min with human plasma, and immediately after aliquots were taken for coagulation tests. Platelet poor plasma (PPP) was used for thrombin time (TT) and fibrinogen (F) measurements, and platelet rich plasma (PRP) for PA assays. TT was prolonged by Hep device. The anticoagulant effect was proportional to Hep concentration (25 - >120 sec; 0.2 to 0.4 g/L). F content was unchanged compared to PPP (316±16.5 vs 322±35.7 mg/dL). The 0.1 M NaSa slice inhibited PA (42% IPA). TT time was enlarged (34.8±9.9 sec.), F content decreased (15% vs PPP) and IAP was higher (90% IAP, p