TICLOPIDINE AND ASPIRIN PRETREATMENT REDUCES COAGULATION AND PLATELETACTIVATION DURING CORONARY DILATION PROCEDURES

Objectives. It is unknown whether a therapeutic combination of aspirin (ASA) and ticlopidine might effectively decrease activation of hemost asis. Background. Percutaneous transluminal coronary angioplasty (PTCA ), rotational atherectomy and stent implantation are pro cedures that fracture or ablate endothelium and plaque, a situation that activates hemostasis. Methods. In 85 patients undergoing PICA for a 77.8 +/- 1% stenosis, we measured markers of coagulation and platelet activation ( thrombin-antithrombin complexes [TAT], prothrombin fragment 1 + 2 [F-1 +2] serotonin and the presence of circulating activated platelets reac ting with monoclonal antibodies against glycoproteins exposed on plate let membranes). Blood samples were drawn from a peripheral vein and fr om the coronary ostium before the procedures. Both immediately and 10 min after angio plasty, and 10 min afterward, samples were collected f rom a probing catheter (0.018 in. [0.46 cm]) positioned beyond the ste nosis. All patients were being treated with antianginal drugs and ASA, 250 mg/day. Seventy of them had taken ticlopidine, 250 mg, twice dail y for less than or equal to 1 day (less than or equal to 24 h) (n = 28 ) or for greater than or equal to 3 days (greater than or equal to 72 h) (n = 42). Heparin (150 U/kg) was administered before angioplasty. T hirty patients underwent PICA; 15 of them were not treated with ticlop idine and 15 were given ticlopidine (greater than or equal to 72 h). T hirty-five patients had stent implantation, 20 rotational atherectomy. Results. Before and during the procedures, there was greater thrombin generation (expressed by higher TAT and F-1+2 plasma levels) in patie nts not taking ticlopidine or taking it for less than or equal to 24 h (p < 0.05). Platelet activation and plasma serotonin levels were also significantly higher in the no ticlopidine or less than or equal to 2 4-h ticlopidine groups. Conclusions. The combined use of ticlopidine, ASA and heparin effectively controls activation of coagulation in pati ents with stable or unstable angina undergoing coronary dilation.