Purpose of review: Until recently, little was known about the long-term outcome of pulmonary embolism. Long-term mortality and recurrence rates, the case fatality rate of recurrent events, and the frequency of persistent vascular defects remained largely unknown. Improvements in our knowledge of these aspects may help to define the optimal long-term treatment of pulmonary embolism. This review will address these issues.
Recent findings: The death rate after pulmonary embolism is less than 5% during 3-6 months of anticoagulant treatment, provided that the patient is hemodynamically stable and free of major underlying disease. The rate of recurrent thromboembolism is less than 5% on anticoagulant therapy, reaching 30% after 10 years. Recurrences are more likely to take the form of a new pulmonary embolism than deep venous thrombosis. Chronic thromboembolic pulmonary hypertension occurs in less than 5% of the patients. Most patients have persistent perfusion defects after the initial episode and further studies are required to determine the long-term significance of this finding.
Summary: Pulmonary embolism has a higher mortality rate than deep venous thrombosis. Patients with pulmonary embolism have no higher risk of recurrence, but any recurrence is more likely to be a new pulmonary embolism than a deep venous thrombosis. A significant number of patients develop persistent perfusion defects after pulmonary embolism.