Determine usefulness of thromboelastography (TEG) as a valuable tool in ex-vivo assessing platelet response to aspirin and clopidogrel (dual) treatment and on-treatment platelet reactivity during acute ST segment elevation myocardial infarction (STEMI) in an acute phase during primary PCI (PPCI) and also during recovery been on maintenance medical therapy and to determine the correlation between platelet response to clopidogrel treatment and the outcome of patients.