PAH is characterized by dyspnea, fatigue, and lower extremity edema as a result of heart failure. In PAH, in situ thrombosis may occur in the lungs, and pulmonary endothelial dysfunction is well-recognized. As aspirin inhibits platelet aggregation, there may be value in using aspirin to treat PAH. Simvastatin has beneficial effects on blood vessels in other types of cardiovascular disease. Therefore, simvastatin may similarly benefit patients with PAH.