BACKGROUND Stent thrombosis is potentially lethal complication with huge economic burden. The role of insufficient response to antiplatelet therapy is still unclear reason for its occurrence. CASE REPORT We presented 54-year-old man with recurrent stent thrombosis on the 4th, 9th and 12th day after the primary percutaneous coronary intervention in spite of double antiaggregation therapy (aspirin+clopidogrel). All possible procedural causes were excluded and reimplantation of intracoronary stent was insufficient to resolve the problem, so four platelet tests were performed: flow cytometry, Platelet Function Analyzer-100 test, aggregometry, and determination of gene polymorphism for P2Y12 receptor (directly involved in the mechanism of thienopyridine), and GPIIbIIIa receptor (final receptor in aggregation). The patient was the carrier of the major haplotype H1H1 for P2Y12 receptor and minor A1A2 for GPIIbIIIa receptor. The results of all the performed tests showed insufficient antiplatelet effect of aspirin and sufficient response to thienopyridin (not to clopidogrel, but to ticlopidine). CONCLUSION Performance of platelet function tests is necessary in the case of major adverse cardiac events especially stent thrombosis, after implantation of intracoronary stent.

Environmental protection and energy saving are crucial problems set up against today's cement industry. The use of industrial by-products such as silica fume, slag, lime and fly ash in the concrete as cement substitution reduce cement production, and consequently lower the CO2 emission and save energy. This research work is inspired with the idea of replacing part of the cement with by-products of thermal power plants and metallurgical industry. Research already done in this area show that concrete prepared with blended cements has better permeability properties than the ordinary Portland cement concrete. In the present research emphasis was given on deformation properties of concrete and the effect of quaternary blended cements on total shrinkage, creep and mechanical properties of concrete. After performing shrinkage and creep tests and obtaining experimental results, shrinkage strain and creep coefficient were calculated according to European standard EN 1992-1 and Gardner/Lockman model, in order to compare the results and evaluate whether the values proposed by standards and model can be used during structural design of concrete prepared with quaternary blended cement.