Role of iloprost and bosentan in pulmonary arterial hypertension

BACKGROUND: Pulmonary hypertension is a disorder that is perpetually fatal unless a tentative therapy is instituted. It can be described as a syndrome considering its clinical and pathophysiological manifestations. In this disorder, there is an imbalance within the vascular mediators which possibly arises due to pulmonary endothelial cell injury or dysfunction. Pharmacotherapy in PAH is aimed to reverse the imbalance present among the chemical mediators, offer relief to patients from symptoms and prolong their survival. In addition to other supportive measures, iloprost and bosentan form the cornerstone of treatment. Iloprost, a vasodilator and stable analogue of prostacyclin, confers great benefit through vasodilation, antiproliferative effects and inhibition of platelet aggregation. Bosentan, an oral non-specific endothelin-receptor antagonist with dual activity on both ETA and ETB receptors, has been shown to improve the patient's quality of life on the overall. METHOD: Review of relevant literature was conducted using manual library search and internet articles. The key words employed were pulmonary hypertension, prostacyclin, endothelin-receptor antagonist, hereditary haemorrhagic telangiectasia, iloprost and bosentan. The National Heart, Lung and Blood Institute website was also used in the course of this review. RESULTS: Several studies were able to outline the haemodynamic advantages of iloprost and bosentan in pulmonary arterial hypertension, as evident by improvement in six-minute walk test of patients treated with these agents. CONCLUSION: This review was able to outline the pharmacotherapeutic benefits and role played by inhaled iloprost (in addition to its stable nature and minimal adverse effects) and bosentan in the management of PAH. Several studies have shown that these agents improve the patient's quality of life on the overall considering their favourable effect on pulmonary haemodynamics, symptoms reduction and exercise tolerance.