A 70-year-old woman presented with acute coronary syndrome. Coronary angiography documented occlusion of the left circumflex coronary artery, and coronary angioscopy showed large red thrombi at the site of occlusion. These thrombi were aspirated using a RESCUE thrombectomy catheter, after which coronary flow was reestablished. Histological examination of the aspirated thrombi revealed platelets, irregularly intermingled erythrocytes, and a large number of leukocytes (mainly neutrophils); tissue resembling vascular endothelium also was present.