Summary
Patients with high-risk pulmonary embolism (PE), i.e. those with shock or hypotension
at presentation, are at high risk of in-hospital death, particularly during the first
hours after admission. A meta-analysis of trials which included haemodynamically compromised
patients indicated that thrombolytic treatment significantly reduces the rate of inhospital
death or PE recurrence. Therefore, thrombolysis should be administered to patients
with high-risk PE unless there are absolute contraindications to its use. Uncontrolled
data further suggest that thrombolysis may be a safe and effective alternative to
surgery in patients with PE and free-floating thrombi in the right heart. On the other
hand, normotensive patients generally have a favourable short-term prognosis if heparin
anticoagulation is instituted promptly, and they are thus considered to have non-high-risk
PE. Generally, the bleeding risk of thrombolysis appears to outweigh the clinical
benefits of this treatment in patients without haemodynamic compromise. However, within
the group of normotensive patients with PE, some may have evidence of right ventricular
dysfunction on echocardiography or computed tomography, or of myocardial injury based
on elevated cardiac biomarkers (troponin I or T, heart-type fatty acid-binding protein).
These patients have an intermediate risk of an adverse outcome in the acute phase
of PE. Existing data suggest that selected patients with intermediate-risk PE may
benefit from early thrombolytic treatment, particularly if they have a low bleeding
risk. However, controversy will continue to surround the optimal treatment for this
group until the results of a large ongoing thrombolysis trial are available in a few
years.
Keywords
Pulmonary embolism - thrombolysis / thrombolytic agents - plasminogen activators -
thrombosis - venous thrombosis
