We describe the clinical and echocardiographic findings in eight patients with right atrial spontaneous echo contrast who were identified from 648 consecutive patients undergoing transesophageal echocardiography. Common findings in these patients were right atrial enlargement (8 patients), tricuspid regurgitation (7 patients), atrial fibrillation or flutter (6 patients), elevated right ventricular pressure (5 patients), moderate or severe mitral valve disease (5 patients), and right to left interatrial shunts (3 patients). Right heart catheterization in three patients showed markedly elevated right atrial, right ventricular, and pulmonary artery pressures. Two patients had thromboembolic events-one patient had recurrent pulmonary emboli, and another patient with an atrial septal aneurysm had recurrent transient ischemic attacks. Right atrial echo contrast is an uncommon finding at echocardiography that is associated with severe right heart dysfunction. It may also be associated with paradoxical or pulmonary embolism.