Chronic Thromboembolic Pulmonary Hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a distinct type of pulmonary hypertensive disease, characterized by incomplete or abnormal resolution of acute pulmonary embolism such that residual emboli become organized and fibrotic. CTEPH can occur in patients without a prior history of venous thromboembolism, and is diagnosed based on precapillary pulmonary hypertension on right heart catheterization with evidence of chronic emboli on ventilation/perfusion scan, chest imaging, or pulmonary angiogram. Pulmonary endarterectomy (PEA) is often curative, and results in improved survival. In patients for whom PEA is not feasible, medical therapy has been effective in improving hemodynamics and functional capacity.