Alteplase Treatment of Acute Pulmonary Embolism in the Intensive Care Unit

Acute pulmonary embolism is a deadly event that occurs in 1 per 1000 persons and is responsible for 50 000 to 100 000 deaths each year in the United States.^1–3  A pulmonary embolism is an obstruction of the pulmonary artery or one of its branches by a thrombus. The signs and symptoms range from massive pulmonary embolism that results in unstable hemodynamic status to a small peripheral embolus that can be asymptomatic. To aid in the delineation of the types of pulmonary embolism, the American Heart Association has proposed several definitions⁴  (Table 1). These definitions have been used in clinical trials and practice guidelines to help stratify patients and aid in treatment selection.

Approximately 44% of patients who have pulmonary embolism have a confirmed deep vein thrombosis.⁵  The pathogenesis of venous thromboembolism can be explained on the basis of the Virchow triad^6...