Current Management of Pulmonary Hypertension

Abstract

In Brief There is an increased awareness and recognition of pulmonary hypertensive disorders over the last 2 decades. This has paralleled the enhanced understanding of the pathogenesis and pathophysiology of these processes. Particularly, the genetic abnormalities in patients with familial primary pulmonary hypertension and primary pulmonary hypertension in patients with hereditary hemorrhagic telangiectasia have been described. Fortunately, some of the improved knowledge has furthered treatment options and other novel therapies. Despite these new developments, there remains a significant need for improved treatment options for these patients; the survival can still be as short as 6 months in patients with World Health Organization (WHO)/New York Heart Association Class IV symptoms. Clinically significant pulmonary hypertension is considered to be present when pulmonary artery mean pressure is 25 mm Hg or above. A new WHO classification of pulmonary hypertensive disorders was proposed in 1998. The new classification replaced the general categories “primary” and “secondary” pulmonary hypertension and sought to categorize patients into distinct groups with common pathophysiological abnormalities and accordingly similar treatment options. Once the correct cause of pulmonary hypertension is established, management consists of disease-specific treatment, general medical treatment, and possibly pulmonary vasodilator therapy, anticoagulation, or surgery. Pulmonary vasodilator therapy is recommended for patients with pulmonary arterial hypertension and select patients with sarcoidosis and small vessel thromboembolic disease. Titrated calcium channel blockers are now recommended in those patients with a favorable acute vasodilator response. Prostacyclin and its analogs are effective in the treatment of pulmonary arterial hypertension. Continuous intravenous epoprostenol and subcutaneous treprostinil infusion are approved therapies. Bosentan, an oral agent that blocks endothelin A and B receptors, was also approved in 2001 for treatment of patients with pulmonary arterial hypertension. Surgical and invasive options for conditions that cause severe pulmonary hypertension have not substantially changed over the last 5 years. These treatments include atrial septostomy, pulmonary thromboendarterectomy, correction of congenital or valvular heart disease, and lung or heart-lung transplantation. Future medical therapies will be first focused on better delivery systems for prostacyclins, improved endothelin antagonists, and the introduction of other groups of drugs. Prevention of pulmonary hypertension in at-risk groups, including those who are carriers for inherited primary pulmonary hypertension, and gene therapies for patients with specific genetic defects are treatment options that will hopefully be available in the not so distant future. Pulmonary hypertensive disorders may occur as result of various cardiac, pulmonary parenchymal, and vascular diseases. The genetic basis for the development of inherited primary pulmonary hypertension has recently been reported. Improved recognition and better understanding of the pathophysiology of these disorders has led to new treatment options. A new classification system was introduced in 1998. Once patients are accurately diagnosed according to the correct classification, specific therapy can be directed. Pulmonary artery vasodilators are the mainstay of therapy for patients with pulmonary arterial hypertension. Others require specific medical therapy. Select patients may be candidates for surgical therapies, and it is imperative to identify patients who may benefit from pulmonary endarterectomy. This article reviews the current treatment options and potential future therapies for patients with pulmonary hypertension.