Twenty-one of 64 patients (33%) with pulmonary embolisms with right ventricular (RV) dilation and 6 of 126 patients (5%) with pulmonary embolisms without RV dilation died during hospitalization (p <0.001). In the 64 patients with RV dilation, in-hospital mortality occurred in 2 of 18 hemodynamically unstable patients (11%) who underwent pulmonary embolectomy, in 2 of 6 hemodynamically stable patients (33%) treated with thrombolytic therapy plus intravenous heparin, and in 17 of 40 hemodynamically stable patients (43%) treated with intravenous heparin (p <0.025 comparing pulmonary embolectomy with no pulmonary embolectomy).