BACKGROUND Coronary stent thrombosis is a catastrophic complication of percutaneous coronary intervention. There is a paucity of long-term data regarding the clinical outcome of patients who have suffered stent thrombosis. MATERIAL/METHODS We sought to assess the long-term clinical outcome of patients who suffered de novo ST-segment elevation myocardial infarction as well as those who suffered ST-segment elevation myocardial infarction as a result of stent thrombosis. In both patient groups, major cardiac adverse events were studied during a 1-year follow-up period. RESULTS A total of 1890 consecutive patients who presented with ST-segment elevation myocardial infarction during the period January 2003 to December 2005 were studied: 1843 (97.5%) suffered de novo ST-segment elevation myocardial infarction, and 47 (2.5%) suffered ST-segment elevation myocardial infarction as a consequence of stent thrombosis. The rate of cardiogenic shock was significantly higher in the stent thrombosis group than in the de novo thrombosis group (21.3% vs 4.8%, respectively) (P<0.001). Mortality rates at 30 days (6.4% vs 8.8%) and at 1 year (17.0% vs 14.9%) showed no significant difference between the 2 groups. The repeat revascularization rate was higher among patients with post-stent thrombosis (35.7% vs 9.1%) (P<0.001), as was the major cardiovascular event rate (57.1% vs 31.2%) (P<0.001). CONCLUSIONS The long-term clinical outcome of patients who have suffered stent thrombosis is poor. Additional research is warranted to further improve therapeutic measures associated with stent thrombosis.