Patient and disease characteristics of pulmonary arterial hypertension patients for prostacyclin receptor agonist selexipag treatment initiation

Aim: to evaluate demographic and disease characteristics in pulmonary arterial hypertension (PAH) patients, for which selexipag is prescribed as PAH-specific treatment.Materials and methods: the study enrolls 73 patients with PAH, where there were 49 patients with idiopathic PAH and 24 patients with associated conditions. These patients were diagnosed in department of pulmonary hypertension and heart disease of the National Medical Research Centre of cardiology named after academician E.I. Chazov of Ministry of Health. Clinical, functional and hemodynamic characteristics of PAH patients were examined. The diagnosis was confirmed according to Eurasian (2019) and Russian (2020) guidelines for the diagnosis and treatment of pulmonary hypertension.Results: At selexipag initiation, median of patient`s age was 43 years, 86,3% were female. Etiological analysis revealed idiopathic PAH in 49 (67,1%) patients, 24 (32,9%) had associated conditions: 14 (19,2%) had connective tissue disease-associated PAH, 6 (8,2%) had PAH after correction of the initial heart defect, 4 (5,5%) had HIV-associated PAH. The median 6-minute walking distance (6MWD) was 370 (300,0-443,75) m, which was corresponding to WHO functional class III, the median Borg dyspnea index was 5 (3,0-6,0). 7 (9,6%) patients did not undergo 6MWD due to severity of their condition. According to right heart catheterization data the median mean pulmonary arterial pressure was 58,5 (48,25-65,0) mmHg, the median right atrium pressure was 7,5 (5,0-10,0) mmHg, the median venous oxygen saturation 58,5% (56,0-66,0), the median cardiac index was 2,0 (1,6-2,5) liter/min/ m2, the median pulmonary vascular resistance was 15,0 (10,3-19,1) Wood units. At selexipag initiation, according to Eurasian (2019) and Russian (2020) guidelines 1 (1,3%) was at low risk, 21 (28,8%) were at intermediate risk and 51 (69,9%) were at high risk of 1-year mortality. Due to risk status, selexipag was initiated in double (50,7%) and triple (49,3%) PAH-specific therapy.Conclusions: At selexipag initiation, PAH-patients typically have WHO FC III and are at high risk, despite receiving PAH-specific treatment. Selexipag was prescribed as part of a combination regimen in most patients.