Aim Pulmonary arterial hypertension (PAH) is an increasingly recognised complication of systemic lupus erythmatous, but may remain underdiagnosed if asymptomatic.

The purpose of this study is to assess correlation of six minute walk test (6WMT) and serum pro-BNP levels with echocardiographic findings of pulmonary arterial hypertension in patients with systemic lupus erythematosus.

Methods This is a prospective cross sectional study of 50 SLE patients using resting transthoracic echocardiography to estimate the systolic pulmonary artery pressure (sPAP).

Results Five out of 50 patients were diagnosed to have PAH with sPAP >30 mm Hg (range 31–40 mmHg) based on echocardiography. Spirometric parameters also did not show any difference between the two groups(p>0.05), but the difference in total distance walked in six minute and serum proBNP level between SLE patients with and without PAH was considered significant(p<0.05). A high correlation was found between pulmonary artery pressure and serum proBNP level but not between pulmonary artery pressure and the six minute walked distance in SLE patients.

Conclusion The point prevalence of PAH in SLE patients was 10% in our study and the significant correlation between pulmonary artery pressure and serum proBNP level suggests that it can be used as a valuable marker for early diagnosis of asymptomatic pulmonary hypertension in patients with systemic lupus erythematosus.