Purpose of review: Venous thromboembolism is a spectrum of disease comprising deep vein thrombosis, thrombus in transit, acute pulmonary embolism, and chronic thromboembolic pulmonary hypertension (CTEPH) as a rare and late possible sequela.
Recent findings: On the basis of a prospective long-term study, the incidence of CTEPH is estimated at 3.8% within 2 years of all patients surviving an episode of symptomatic idiopathic pulmonary embolism. Young age, a large perfusion defect, and idiopathic clinical presentation are associated with a higher probability of CTEPH. Current pathophysiological concepts suggest a misguided thrombus resolution process that is triggered by infection, inflammation, autoimmunity, and malignancy. Diagnosis and therapy of CTEPH are interdisciplinary achievements and nowadays still based on a positive lung perfusion scan and for assessment of operability on a classical pulmonary angiography. Treatment of choice is surgical pulmonary endarterectomy of the pulmonary obstructions, which leads to restoration of normal pulmonary hemodynamics at rest in nearly 80% of patients. In expert centers, surgical mortality is under 10%.
Summary: CTEPH has emerged as a 'dual' pulmonary vascular disorder with major vessel vascular remodeling of thrombus organization, combined with a small vessel pulmonary arteriopathy that is a target for classic vasodilator treatments.