The relationship between spontaneous echocontrast, transesophageal echocardiographic parameters, and blood hemoglobin levels.

Background: Spontaneous echocontrast (SEC) or "smoke" is an intracavitary echocardiographic finding seen in situations of stasis or low blood flow. Increased hematocrit and fibrinogen levels have been associated with SEC in prior studies. Whether low hemoglobin (Hb) levels are an independent predictor of lower prevalence of SEC is a question that remains unanswered.