Transesophageal echocardiography in evaluation of atrial masses.

Clinical and transthoracic echocardiographic findings in 92 patients who had atrial mass lesions identified by transesophageal echocardiography were retrospectively analyzed. Transthoracic echocardiography failed to diagnose or misdiagnosed 16 patients with small (< 3 cm) atrial thrombi, patients with thrombi localized to the appendage, or patients with technically difficult studies. The 3 patients with atrial myxoma who were not detected or were misdiagnosed by transthoracic echocardiography had small tumors (< 3 cm) or origin from the free wall of the atrium away from the atrial septum. Transthoracic study also failed to diagnose or misdiagnosed normal anatomic variants in 17 of 32 patients. In conclusion, transesophageal echocardiography is superior to the transthoracic study in evaluating the etiology and significance of atrial mass lesions.