Thrombolysis for pulmonary embolism.
More than 10 years ago, thrombolytic therapy with urokinase and streptokinase for pulmonary embolism was found to have considerable advantages over standard heparin therapy. After the introduction of alteplase, a recombinant tissue plasminogen activator, further studies confirmed this benefit. However, thrombolytic therapy for pulmonary embolism has not gained universal acceptance, even though it now has U.S. Food and Drug Administration approval. Clear advantages of thrombolytic therapy over conventional heparin therapy are improved pulmonary capillary blood volume, accelerated clot lysis and accelerated pulmonary perfusion. Earlier reversal of right-sided heart failure, a lower incidence of recurrent pulmonary embolism, a reduced risk of chronic pulmonary hypertension and reduced mortality have been claimed as advantages, but these have not been adequately proved. A recent survey suggests that about half of all patients with pulmonary embolism are potential candidates for thrombolytic therapy. In a subset of patients with hemodynamic compromise, thrombolysis has definite advantages over heparin therapy.