Current understanding of the role of bosentan in inoperable chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension may occur in the context of incomplete lysis of acute pulmonary emboli, resulting in the obstruction of pulmonary blood flow, as well as progressive right ventricular dysfunction and failure. The treatment of choice for this condition is surgical removal of the obstructing material. However, in many patients, surgery is not possible due to either an unfavourable distribution of the disease, the development of a concurrent small vessel pulmonary arteriopathy, or the presence of significant comorbid conditions. There is increasing evidence that the medical therapies that are used in other forms of pulmonary hypertension may also be effective in inoperable chronic thromboembolic pulmonary hypertension. This article examines the rationale for the use of the oral dual endothelin receptor antagonist bosentan in this life-threatening condition.