The incidence of left atrial (LA) spontaneous echo contrast (SEC) and the clinical and echocardiographic variables related to it were prospectively evaluated in a series of 60 patients with mitral stenosis (MS) undergoing transoesophageal echocardiography (TEE) with a 5 MHz multiplane transducer. LA-SEC was found in 39 patients (65 %) employing TEE. Statistical analysis showed a significant relationship between the presence of SEC and MS without mitral regurgitation (MR) (P«)’o5), MS with ~MR grade II