Five patients with pulmonary embolism, in whom rightsided intracardiac thromboembolus was detected by echocardiography and confirmed by either angiography, surgery or postmortem examination, are described. One of these patients died from massive pulmonary embolism after right heart catheterization. In two patients treated medically, either partial or total lysis of the thromboembolus was demonstrated echocardiographically; in another two patients, the right atrial thromboembolus was successfully removed surgically. Typical locations and echocardiographic characteristics of right-sided throm-boemboli are described. The potential usefulness of two-dimensional echocardiography in both the diagnosis and the management of patients with right-sided intracardiac thromboembolism is discussed.