**8. Conclusion**

Risk stratification of acute PE is fundamental not only to select an appropriate treatment strategy, but also to potentially reduce costs of management (Figure 2). An appropriate risk stratification algorithm would include clinical, imaging and biomarkers. High risk PE is diagnosed in the presence of shock or persistent hypotension and should warrant urgent management. Thrombolysis with alteplase (rtPA), streptokinase, or urokinase is the recommended therapy. Embolectomy could represent an alternative therapy for patients with shock in the acute setting when thrombolysis has been unsuccessful.

Hemodynamically stable patients without RV dysfunction or myocardial injury are at lowrisk for PE-related adverse events. These patients may be eligible for early hospital discharge or even outpatient treatment.

In the remaining normotensive patients, a plausible strategy is to combine biomarkers with echocardiography. The presence of RV dysfunction and myocardial injury identifies patients at intermediate risk.

Whether intermediate risk patients will have any survival benefit with early initiation of reperfusion therapy (and what type of therapy) is not well accepted. Current recommendations proposed thrombolysis be instituted in selected patients at high risk for adverse events without contraindications (Grade IIB ESC and ACCP VIII Edition), and intravenous unfractionated heparin should be reserved to conditions in which thrombolysis is contraindicated (Grade IA ESC and ACCP VIII Edition). An ongoing study assessing the benefit of thrombolysis as compared with anticoagulation in hemodynamically stable patients with evidence of RV dysfunction and an elevated troponin levels will hopefully provide some insights (NCT00639743).
