Background Pulmonary Arterial Hypertension (PAH) is a major cause of mortality in SSc. N-terminal pro-brain natriuretic peptide (NT-proBNP) has emerged as a candidate biomarker that may enable the early detection of systemic sclerosis-related pulmonary arterial hypertension (SSc-PAH).
Objectives To incorporate N-terminal pro-brain natriuretic peptide (NT-proBNP) into a screening algorithm for systemic sclerosis-related pulmonary arterial hypertension (SSc-PAH) that could potentially replace transthoracic echocardiography (TTE) as a less costly and more convenient “first tier” test.
Methods NT-proBNP levels were measured in patients from 4 clinical groups: a group with right heart catheter (RHC) diagnosed SSc-PAH prior to commencement of therapy for PAH; a group at high risk of SSc-PAH based on TTE; a group with interstitial lung disease; and systemic sclerosis (SSc) controls with no cardiopulmonary complications. NT-proBNP levels were compared using ANOVA and correlated with other clinical variables using simple and multiple linear regression. ROC curve analyses were performed to determine the optimal cut-point for NT-proBNP and other clinical variables in prediction of PAH.
Results NT-proBNP was highest in the PAH group compared to other groups (p<0.0001), and higher in the risk group compared to controls (p<0.0001). NT-proBNP was positively correlated with systolic pulmonary artery pressure (PAP) on TTE (p<0.0001), and mean PAP (p=0.008), pulmonary vascular resistance (p=0.001) and mean right atrial pressure (p=0.006) on RHC. A composite model wherein patients screened positive if NT-proBNP ≥209.8pg/ml, and/or DLCOcorr <70.3% with FVC/DLCOcorr ≥1.83, had a sensitivity of 100% and specificity of 77.8% for SSc-PAH.
Conclusions We have proposed a screening algorithm for SSc-PAH, incorporating NT-proBNP level and PFTs. This model has high sensitivity and specificity for SSc-PAH and if positive, should lead to TTE and confirmatory testing for PAH. This screening algorithm needs to be validated prospectively.
Disclosure of Interest None Declared