This study was initiated on the preliminary premise that a thrombus whose formation was triggered by a thrombogenic substrate, such as within an atherosclerotic plaque (Tissue factor initiated thrombus), may evolve differently than the one evolving at the site of a recently implanted stent (foreign body triggered). Consequently, the thrombus composition of a de novo clot could differ from the other one, extracted during the occurrence of a subacute thrombosis, regarding the number of various cells, the amount of fibrin and platelet aggregates and the relationship among these components. In addition, it seems relevant to evaluate the numbers and the distribution of the local monocytes, once these cells may interact with platelets (via cell -adhesion mechanisms e.g., by CD31 [PECAM-1]) and by the extrinsic coagulation pathway (via TF/FVII elaborated by plaque-resident macrophages). Such a distinction, if eventually found, may reveal the mechanisms of thrombosis within coronary arteries, and may have clinical implications.