Evaluation and management of chronic pulmonary thromboembolic disease.

Pulmonary embolism (PE) is common and the majority of patients survive the acute event. Survivors are at increased risk for adverse outcomes, including persistent thrombi, recurrent embolism, chronic thromboembolic pulmonary hypertension (CTEPH), and death. Anticoagulation protects against recurrence, which has a high mortality rate. The recommended duration of anticoagulation for patients with reversible PE risk factors is 3 months. For patients with idiopathic PE or persistent risk factors, extended duration of anticoagulation is preferred, balanced with an individual patient's risk of hemorrhage, which in itself is a major cause of morbidity and mortality. Among patients with malignancy who develop venous thromboembolism (VTE), low-molecular-weight heparin is preferred over oral vitamin K antagonists in the first 6 months. Thereafter, anticoagulation should be continued indefinitely with either low-molecular-weight heparin or oral vitamin K antagonists. Inferior vena cava filters are not routinely recommended and should only be used in patients who have a contraindication to anticoagulation. Patients who have had VTE and with persistent or recurrent dyspnea should be evaluated for recurrence of VTE or development of CTEPH. Patients with recurrent VTE should be anticoagulated indefinitely. Routine screening for CTEPH in asymptomatic patients is not recommended. Echocardiography often provides the first indication of the presence of pulmonary hypertension. Once presence of CTEPH is established by right-sided heart catheterization and perfusion imaging (ie, ventilation/perfusion scintigraphy, computed tomography angiography, or pulmonary angiography), patients should be referred early to a center with expertise, as it is potentially surgically curable by pulmonary endarterectomy. Those who are deemed inoperable after being evaluated may gain symptomatic benefit from drugs approved for idiopathic pulmonary arterial hypertension. Lung transplantation may also be an option for patients who are not candidates for pulmonary endarterectomy.