Current Controversies in Thrombolytic Use in Acute Pulmonary Embolism

Acute pulmonary embolism (PE) has an annual incidence of 100,000 cases in the United States and is divided into three categories: nonmassive, submassive, and massive. Several studies have evaluated the use of thrombolytics in submassive and massive PE.

Our aim was to provide emergency physicians with an updated review of the controversy about the use of thrombolytics in submassive and massive PE.

Nonmassive PE is defined as PE in the setting of no signs of right ventricular strain (echocardiogram or biomarker) and hemodynamic stability. Submassive PE is defined as evidence of right ventricular strain with lack of hemodynamic instability. Massive PE occurs with occlusive thromboembolism that causes hemodynamic instability. Thrombolysis is warranted in patients with massive PE. Thrombolytic use in submassive PE with signs of right ventricular strain or damage presents a quandary for physicians. Several recent studies have evaluated the use of thrombolytics in patients with submassive PE. These studies have inconsistent definitions of submassive PE, evaluate differing primary outcomes, and use different treatment protocols with thrombolytics and anticoagulation agents. Although significant study heterogeneity exists, thrombolytics can improve long-term outcomes, with decreased bleeding risk with half-dose thrombolytics and catheter-directed treatments. Major bleeding significantly increases in patients over age 65 years. The risks and benefits of thrombolytic treatment-primarily improved long-term outcomes-should be considered on a case-by-case basis. Shared decision-making with the patient discussing the risks and benefits of treatment is advised.

Thrombolytic use in massive PE is warranted, but patients with submassive PE require case-by-case analysis with shared decision making. The risks, including major hemorrhage, and benefits, primarily improved long-term outcomes, should be considered. Half-dose thrombolytics and catheter-directed treatment demonstrate advantages with decreased risk of bleeding and improved long-term functional outcomes. Further studies that assess risk stratification, functional outcomes, and treatment protocols are needed.