Real-world evidence on pulmonary arterial hypertension: interim analysis from the Italian observational study INSPECTIO

Abstract Background Pulmonary arterial hypertension (PAH) is a rare, progressive disease leading to right-sided heart failure. The interest in risk assessment based on non-invasive parameters is growing, and insights from clinical practice are needed in this regard. INSPECTIO is an Italian observational study aimed at filling this knowledge gap. The results of an interim analysis at month 12 are presented below. Purpose The primary objective was to assess the change from baseline to month 12 in the number of the non-invasive low-risk parameters among World Health Organization functional class, 6-minutes walking distance, Brain Natriuretic Peptide (BNP) or N-terminal proBNP. Secondary objectives are the evaluation of echocardiographic and haemodynamic parameters, and the proportion of patients in which the therapy was optimized according to the guidelines. Methods Prospective, multicentre study on PAH patients at low/intermediate mortality risk treated with macitentan and/or selexipag as part of the oral combination therapy. Results Among 177 patients who were enrolled in 29 centres, 148 patients [median age 63.0 years (Q1/Q3: 53.5/73.0), 76.4% females] completed the 12-month follow up and were considered for this analysis. The median time from PAH diagnosis was 22.6 months (4.9/60.1). Sixty-four (43.2%) patients had idiopathic PAH; 4 (2.7%) heritable; 80 (54.1%) associated with other diseases [58 (72.5%) connective tissue disease, 11 (13.8%) congenital heart disease corrected for at least one year, 5 (6.3%) portal hypertension, 5 (6.3%) human immunodeficiency virus infection, 1 (1.3%) drug and toxins]. At baseline, 45.9% patients and 28.4% were in double and triple oral combination therapy, respectively. Primary objective: at month 12, the number of noninvasive low-risk parameters increased in 43 (29.1%) patients and remained stable in 80 (54.1%) patients [mean change 0.16 (p=0.017)]. The values at baseline, at month 12 and the change from baseline for each noninvasive parameter are shown in Table 1. Mean right atrial (RA) area (end-systole) and tricuspid annular plane systolic excursion (TAPSE) remained unchanged while a reduction of systolic pulmonary artery pressure (sPAP) was observed. Regarding the haemodynamic parameters, the mean pulmonary arterial pressure decreased [median change -4.5, (p=0.0346)], while cardiac index, pulmonary vascular resistance, and RA pressure remained stable (Table 2). The number of patients on triple therapy increased from 42 to 51 (+21.4%). Conclusions This study confirms that a noninvasive low-risk profile can be achieved with current combination PAH therapy. The modest or absent changes in echocardiographic and hemodynamic parameters suggest that treatment of PAH in real world is yet to be improved; on the other hand, the optimization of therapy in a significant portion of patients can possibly account for the improvement or stabilization observed.Noninvasive parametersEcho and hemodynamic parameters