Catheter-Based Approaches for the Treatment of Acute Pulmonary Embolism.

Except when contraindicated, anticoagulation should be initiated when pulmonary embolism (PE) is strongly suspected and the bleeding risk is perceived to be low, even if the evaluation has not been completed. Low-risk patients with acute PE are simply continued on anticoagulation. Severely ill patients with high-risk (massive) PE require aggressive therapy, and if the bleeding risk is acceptable, systemic thrombolysis should be considered. However, despite clear evidence that parenteral thrombolytic therapy leads to more rapid clot resolution than anticoagulation alone, the risk of major bleeding including intracranial bleeding is significantly higher with thrombolytic therapy. It has been demonstrated that right ventricular dysfunction as well as abnormal biomarkers (troponin and brain natriuretic peptide) are associated with increased mortality in acute PE. In spite of this, intermediate-risk (submassive) PE comprises a fairly broad clinical spectrum so that there is not a solid evidence base permitting a consistent algorithm for clinicians to follow. Thus, for several decades, thromboembolism basic scientists, clinical trialists, and clinicians have worked toward a lower risk solution for treatment of patients with more than simply low-risk PE. Catheter-based therapy, consisting of various devices and techniques, with or without low-dose thrombolytic therapy, offers one potential solution and continues to evolve.