Pulmonary arterial hypertension.

Pulmonary arterial hypertension is a progressive disease of pulmonary vasculature characterized by increased mean pulmonary arterial pressure and elevated vascular resistance with normal left-sided pressures, differentiating it from left-sided heart disease. The pathogenesis involves thrombosis, vasoconstriction, and remodeling of small pulmonary arteries. It presents with common symptoms such as shortness of breath, chest pain, and decreased exercise tolerance. Left untreated, progressive increase in right ventricular overload leads to right heart failure and death. Over the course of the past decade, better understanding of the pathogenesis and an increasing number of treatment options have resulted in improved prognosis and quality of life.