The Challenge of Intermediate-Risk Pulmonary Embolism.

BACKGROUND: Intermediate-risk pulmonary embolism is a common disease that is associated with significant morbidity and mortality; however, a standardized treatment protocol is not well-established.

AREAS OF UNCERTAINTY: Treatments available for intermediate-risk pulmonary embolisms include anticoagulation, systemic thrombolytics, catheter-directed therapies, surgical embolectomy, and extracorporeal membrane oxygenation. Despite these options, there is no clear consensus on the optimal indication and timing of these interventions.

THERAPEUTIC ADVANCES: Anticoagulation remains the cornerstone of treatment for pulmonary embolism; however, over the past 2 decades, there have been advances in the safety and efficacy of catheter-directed therapies. For massive pulmonary embolism, systemic thrombolytics and, sometimes, surgical thrombectomy are considered first-line treatments. Patients with intermediate-risk pulmonary embolism are at high risk of clinical deterioration; however, it is unclear whether anticoagulation alone is sufficient. The optimal treatment of intermediate-risk pulmonary embolism in the setting of hemodynamic stability with right heart strain present is not well-defined. Therapies such as catheter-directed thrombolysis and suction thrombectomy are being investigated given their potential to offload right ventricular strain. Several studies have recently evaluated catheter-directed thrombolysis and embolectomies and demonstrated the efficacy and safety of these interventions. Here, we review the literature on the management of intermediate-risk pulmonary embolisms and the evidence behind those interventions.

CONCLUSIONS: There are many treatments available in the management of intermediate-risk pulmonary embolism. Although the current literature does not favor 1 treatment as superior, multiple studies have shown growing data to support catheter-directed therapies as potential options for these patients. Multidisciplinary pulmonary embolism response teams remain a key feature in improving the selection of advanced therapies and optimization of care.