N-terminal pro-brain natriuretic peptide is associated with pulmonary hypertension or diastolic dysfunction in patients with systemic sclerosis: An Australian prospective cross-sectional study.

Introduction: Pulmonary arterial hypertension and left ventricular diastolic dysfunction are associated with significant morbidity and mortality in systemic sclerosis. N-terminal pro-brain natriuretic peptide has been proposed as part of composite screening algorithms for pulmonary arterial hypertension. Our aim was to assess the prevalence of pulmonary hypertension and diastolic dysfunction, and evaluate their association with serum N-terminal pro-brain natriuretic peptide in systemic sclerosis patients.

Methods: Patients with systemic sclerosis were prospectively enrolled to undergo N-terminal pro-brain natriuretic peptide testing and transthoracic echocardiography at a tertiary Australian centre from January to October 2022. We collected demographic and transthoracic echocardiography variables including pulmonary hypertension estimated by tricuspid regurgitant velocity and diastolic dysfunction assessed by the ASE/EACVI 2016 guidelines. Pearson's correlation coefficient was used to evaluate association between N-terminal pro-brain natriuretic peptide and echocardiographic parameters.

Results: Sixty-one patients were enrolled (median age = 62 years (interquartile range = 55-69 years); 84% female). Two-thirds of patients had limited systemic sclerosis (40/61). Five patients (8%) had high likelihood of pulmonary hypertension by transthoracic echocardiography. Seven patients (11%) had diastolic dysfunction; however, seven patients (11%) had indeterminate diastology. Six patients underwent right heart catheterisation, with five patients diagnosed with pulmonary hypertension. N-terminal pro-brain natriuretic peptide in patients with pulmonary hypertension or diastolic dysfunction was significantly higher (median = 207 and 226 pg/mL, respectively) compared to patients without either condition (median = 69 pg/mL, p = 0.01). N-terminal pro-brain natriuretic peptide showed a statistically significant although limited correlation with estimated pulmonary pressures measured by tricuspid regurgitant velocity (r = 0.44, p = 0.002) and left ventricular filling pressures (r = 0.27, p = 0.04).

Conclusion: Pulmonary hypertension and diastolic dysfunction are both observed in systemic sclerosis. N-terminal pro-brain natriuretic peptide is associated with both conditions; however, it cannot distinguish between the two disease processes. Right heart catheterisation may be required to make this distinction.