Left atrial appendage spontaneous echo contrast in patients with atrial arrhythmias using integrated backscatter and transesophageal echocardiography

Integrated backscatter (IBS) imaging technology has been used in a wide ran ge of clinical conditions to help characterize tissue abnormalities includi ng myocardial diseases(1-5) and thrombi.(6-8) Previously, we and others(9-1 1) reported quantitative assessment of left atrial (LA) cavity spontaneous echo contrast (SEC) using IBS. However, it is not known whether LA appendag e (LAA) SEC can also be measured quantitatively, and if there exists a rela tion between LAA Doppler flow velocities and a quantitative measure of SEC. Use of IBS in assessing the severity of SEC may reduce errors resulting fr om human subjectivity. SEC assessment is highly influenced by the experienc e level of the operator in the use of transesophageal echocardiography. Ine xperienced observers may either under- or overestimate the presence and sev erity of SEC, leading to a possible change in the clinical management of th e patient. A quantitative IBS evaluation may provide an additional objectiv e tool, if not a replacement, for qualitative assessment of SEC, especially in situations in which an observer may not be comfortable in visually grad ing the presence or severity of SEC. The present study assessed LAA SEC in patients with atrial arrhythmia using IBS and its correlation with qualitat ive grades of SEC and clinical and echocardiographic predictors of thromboe mbolism.