Transesophageal echocardiography (TEE) has been used to identify patients with left atrial thrombi (LAT) and spontaneous contrast echo (SCE). Patients with LAT or SCE are at high risk for cerebral embolism. The aim of this study was to examine the relationship between SCE detected with TEE [5MHz] and coagulation and fibrinolysis factors. We took blood samples from 83 patients to measure plasma levels of TAT, PIC, D-dimer, fibrinogen and thrombomodulin (TM) just before TEE examination. The patients were classified into four groups according to SCE grade based on echo density and area of the left atrium occupied by SCE. Plasma TAT and D-dimer were higher in the high grade SCE group than in the lower SCE group. Plasma TM was lower in the high grade SCE group. From these results, high grade SCE detected by TEE correlates with activation of coagulation and fibrinolysis.