While the diagnostic accuracy of echocardiography alone for the detection of PAH remains suboptimal [13], several algorithms combining clinical features, transthoracic echocardiography, pulmonary function tests, 6 min walking distance (6MWD) test and cardiac biomarkers, namely N-terminal pro-brain natriuretic peptide (NT-proBNP) have been proposed for the detection of SSc patients who should undergo RHC [13,52]. This evidence concerns the gene NPPB and pulmonary arterial hypertension.