Pulmonary arterial hypertension in human immunodeficiency virus infection

Because of the improvement in survival rates of human immunodeficiency virus (HIV)-infected patients after the introduction of combined antiretroviral therapy, pulmonary arterial hypertension (PAH) has become an important cause of morbidity. As the awareness of PAH has increased, it is more likely that this condition will be diagnosed more frequently and earlier in the course of the disease and HIV infection. The etiopathogenesis is not clear; no evidence of direct infection of the pulmonary vascular tree has been found and the current evidence seems to favor a role of dysregulated cytokine response to HIV infection. The pathological changes of plexiform arteriopathy are indistinguishable from the pathological changes of idiopathic pulmonary arterial hypertension (IPAH). Dyspnea is the most common presenting symptom. Echocardiography, though always not accurate in diagnosing PAH and estimating its severity, remains the main screening tool. Right heart catheterization is the gold standard investigation for diagnosis. New therapies like prostanoids, endothelin receptor antagonists, and phosphodiesterase inhibitors have improved the outcome of patients with HIV-associated PAH. However, the overall prognosis of HIV-infected patients who develop PAH still remains poor.