Fibrinolytic therapy in pulmonary embolism

There is reasonable evidence that suggests that fibrinolytic therapy accelerates the

resolution of PE while simultaneously reducing the recurrence of pulmonary embolism; it

can also improve other parameters, such as pulmonary blood flow, lung perfusion, and

right ventricular dysfunction. Unfortunately, conclusive evidence demonstrating a

mortality reduction is not found in the literature, particularly in those patients who are

clinically stable with intermediate to low risk of death. The clinician should assess the

mortality risk of the PE relative to both the potential benefits and the adverse effects of

fibrinolytic therapy for cardiac arrest and the various risk group presentations. In cardiac

arrest related to PE, there are no contraindications to medical fibrinolysis; fibrinolytic

therapy likely offers the reasonable chance at survival. In those patients not in cardiac

arrest, a categorization into high, intermediate, and low risk groups will aid in decision

making. In the absence of significant bleeding risk, those patients who are

hemodynamically unstable or have signs of right ventricular dysfunction would likely

benefit from fibrinolytic agents – i.e., the high risk group. Intermediate risk presentations

demonstrate less benefit such that the consideration of complications not infrequently

outweighs fibrinolytic advantage. The literature is mixed, however, in its

recommendations for the intermediate group. And, lastly, the low risk group does not

benefit from fibrinolysis. Despite this categorization, the decision to administer a

fibrinolytic agent remains challenging; the clinician must consider the risks of PE coupled

with the risks of fibrinolysis, as compared with this medication’s potential benefit. The

decision to administer a fibrinolytic agent in the setting of PE remains highly individual

and is most appropriately addressed by the clinician at the bedside.