[New aspects of blood coagulation inhibitory therapy within the scope of percutaneous transluminal coronary angioplasty (PTCA)].

Percutaneous transluminal coronary angioplasty (PTCA) is increasingly extended to patients with complex stenosis morphology or acute coronary insufficiency syndromes. Especially these patients are at high risk to suffer thrombotic complications during PTCA. Thus an effective anticoagulant regimen is of great importance during PTCA. PTCA-induced damage of the arterial wall induces the formation of a platelet-rich thrombus. After adhesion of platelets to the arterial wall further platelet aggregation is stimulated mainly by activated thrombin, followed by fibrin formation stabilizing the growing thrombus. This article describes the pathophysiologic basis of coagulation and thrombus formation during PTCA and potential targets for a therapeutic intervention. The results of clinical studies regarding the currently available antithrombotic, antiplatelet, and thrombolytic therapies are described. Furthermore, the results are reported of clinical studies of newer anticoagulant strategies such as inhibition of the platelet glycoprotein receptor GP IIb/IIIa with monoclonal antibodies and direct inhibition of activated thrombin with hirudin analogues. At present an aggressive anticoagulant regimen with heparin is recommended during the PTCA procedure. Heparin should not be continued after the intervention unless a complication during the procedure has occurred. Already before PTCA patients should receive 100 mg aspirin daily. Thrombolytic therapy during PTCA has failed to demonstrate an improvement of clinical results. Thus its use should be limited to bail-out situations. First results with hirudin analogues and GP IIb/IIIa receptor antagonists are promising. Further studies are, however, warranted before a general use can be recommended.