In-hospital mortality is high when pulmonary embolism is complicated by hemodynamic instability and/or pulmonary hypertension. Death occurs frequently within the first hours after admission. This implies specific diagnostic and therapeutic management. Spiral CT seems to be an excellent diagnostic procedure in this setting. However, pulmonary angiography and perfusion lung scan can also be employed. Cardiac echography can help in the diagnosis and therapeutic decision making. Supportive therapy mainly includes correction of hypovolemia if present, a limited volume loading in other cases, and the use of dobutamine. Norepinephrine is the drug of choice when hypotension is present. Thrombolytic agents are indicated in case of hemodynamic instability. Modalities of administration and contra indications are currently well established. Surgical embolectomy should be performed in cases of uncontrolled shock, when thrombolysis is contra-indicated or uneffective.