Initial and programmed combination therapy with oral drugs for severe idiopathic pulmonary arterial hypertension

A 49-year-old woman suffering from rapidly progressing right-sided heart failure assessed as World Health Organization functional class (WHO-FC) IV is described. After treatment with oxygen and diuretics, she was in WHO-FC III on admission to our hospital, as confirmed by her poor exercise tolerance in cardiopulmonary exercise testing. Upon detailed examination, she was diagnosed as having idiopathic pulmonary arterial hypertension (IPAH). Right heart cathe-terization (RHC) revealed severe pulmonary hypertension (mPAP = 65 mmHg) with a markedly decreased cardiac index (CI = 1.0 L/minute/m ²), and an acute vasoreactivity test with nitric oxide inhalation did not show any response. Due to her severe condition, we decided to attempt oral combination therapy consisting of bosentan, tadalafl, and beraprost, prescribed in the same order and titrated up to their maximum respective doses, instead of intravenous (IV) epoprostenol therapy. Her clinical symptoms improved day by day, and the hemodynamic parameters recovered to nearly normal ranges about 6 months after initiation of the combination therapy. Initial/programmed oral combination therapy for severe IPAH patients is not yet fully established, and there is less evidence concerning its efficacy than IV epoprostenol therapy. However, it has tremendous advantages for PAH patients when they respond well. It is very important to further identify what types of PAH patients will respond to this oral combination therapy and should be treated with it as the first-line therapy.