Objective. To evaluate predictors of pulmonary arterial hypertension (PAH) in a prospective cohort of patients with systemic sclerosis (SSc).Methods. Routine clinical assessments as well as measurements of the diffusing capacity for carbon monoxide/alveolar volume (DLCO/VA) ratio and N-terminal pro-brain natriuretic peptide (NT-proBNP) level were performed in a prospective cohort of 101 SSc patients who did not have PAH or severe comorbidities. After a planned 36-month followup, we evaluated the predictive value of these parameters for the development of precapillary PAH, as demonstrated by cardiac catheterization, disease progression, and death. Criteria for cardiac catheterization were a systolic pulmonary artery pressure (PAP) of >40 mm Hg on echocardiography, a DLCO value of <50% without pulmonary fibrosis, and unexplained dyspnea. Conclusion. This prospective study identified a decreased DLCO/VA ratio and an increased NT-proBNP as predictors of PAH in SSc. Use of these markers should result in improved PAH risk stratification and allow earlier initiation of therapy.

Objective. To evaluate N-terminal pro-brain natriuretic peptide (NT-proBNP) as a marker of early pulmonary artery hypertension (PAH) and to study changes in the levels of this marker following treatment with dihydropyridine-type calcium-channel blocker (DTCCB) in patients with systemic sclerosis (SSc).Methods. We evaluated 40 consecutive SSc patients who had been hospitalized for followup care (mean ؎ SD age 56 ؎ 11 years and mean ؎ SD duration of cutaneous disease 9 ؎ 9 years; 27 with limited cutaneous and 13 with diffuse cutaneous disease) but who had no clinical symptoms of heart failure and had a normal left ventricular ejection fraction. At baseline, 10 patients had PAH, defined as a systolic pulmonary artery pressure (sPAP) >40 mm Hg, as measured by echocardiography. Levels of NT-proBNP were determined at baseline (after discontinuation of DTCCB treatment for 72 hours), after taking 3 doses of DTCCB following treatment reinitiation (assessment 1), and after 6-9 months of continuous DTCCB treatment (assessment 2) in the 20 patients who attended regular appointments (including the 10 patients with PAH at baseline).Results. At baseline, 13 patients had high NTproBNP values for their ages. High NT-proBNP levels identified patients with PAH with a sensitivity of 90%, a specificity of 90.3%, a positive predictive value of 69.2%, and a negative predictive value of 96%. The NT-proBNP level correlated with the sPAP (r ‫؍‬ 0.44; P ‫؍‬ 0.006). By assessment 1, the number of patients with PAH and high levels of NT-proBNP had decreased from 9 of 10 to 2 of 10 (P ‫؍‬ 0.02). This decrease was partially sustained at assessment 2 (4 of 10 patients; P ‫؍‬ 0.06).Conclusion. NT-proBNP is a useful biologic marker that can be used to diagnose early PAH in SSc patients without clinical heart failure. Measurement of NT-proBNP may be valuable for the evaluation of treatment with DTCCB and vasodilators in patients with PAH.