Use of Epoprostenol in the Treatment of Pulmonary Arterial Hypertension

Pulmonary Hypertension (PH) is defined as a disorder in which the mean Pulmonary Arterial Pressure (mPAP) is greater than 20 mmHg at rest. Pulmonary Arterial Hypertension (PAH) is considered when mPAP is > 20 mmHg and pulmonary vascular resistance (PVR) is ⩾ 3 WU. PAH is a chronic progressive disease resulting in right heart failure and premature death. It is postulated to be due to an inactivating mutation of a gene named bone morphogenetic protein receptor type 2 (BMPR2), whose predominant function is halting vascular proliferation. It has a lamentable prognosis if not rapidly diagnosed and adequately treated. Treatment of PAH has evolved in the past few decades since many related pathways and potential therapeutic targets have been explored. Parenteral prostanoids are the most effective therapeutic options for PAH. Epoprostenol is a synthetic analog of prostacyclin and a potent vasodilator that was Food and Drug Administration (FDA)-approved in December 1995 for intravenous use to treat PAH. It has also been used to treat different PAH subtypes, including connective tissue-related PAH like lupus and systemic sclerosis, congenital heart disease, and drug-induced PAH. It is effective in reducing mortality rates and improving survival rates. Although the use of Epoprostenol for PAH is challenging, it has been one of the most successful therapies used. In this manuscript, we review the pathophysiology of PAH and the risk stratification tool. We also discuss the mechanism of action of PAH-targeted therapies while focusing on the role of epoprostenol that has been investigated in many clinical trials. Finally, we discuss two ongoing clinical trials which highlight some potential therapeutic options.