Recent studies have shown that coronary thrombus histopathology is associated with impaired myocardial reperfusion and poor clinical outcome in patients with acute myocardial infarction (AMI). We sought to investigate the age of thrombi aspirated during percutaneous coronary intervention (PCI) in patients with AMI and evaluate the relationship between histopathologic findings and major adverse cardiac and cerebrovascular events (MACCEs) defined as all-cause death, stroke, or myocardial infarction within 6 months of PCI.