When the heart is burning: amino-terminal pro-brain natriuretic peptide as an early marker of cardiac involvement in active autoimmune rheumatic disease.

BACKGROUND

We evaluated the influence of inflammation on cardiac endocrine function in autoimmune rheumatic disease (RD) patients with preserved left ventricular systolic function.

METHODS

160 consecutive RD patients (29 males, age 55 ± 14 years, left ventricular ejection fraction, LVEF, 63 ± 5%: inflammatory polyarthritis: 13%, systemic sclerosis: 25%, connective tissue diseases: 39%, systemic vasculitides: 23%) and 120 healthy controls (24 males, 55 ± 10 years) underwent clinical, echocardiographic evaluation and blood sampling for erythrocyte sedimentation rate, C-reactive protein (CRP), fibrinogen and plasma NT-proBNP.

RESULTS

A significant correlation was found between plasma NT-proBNP and inflammatory markers (all p<0.001), with CRP and diastolic dysfunction being the only independent predictors of NT-proBNP level. RD patients with active disease (57%) showed higher values of inflammatory markers and NT-proBNP (all p<0.01). Patients with subclinical cardiac involvement (Stage B by ACC/AHA HF-classification) had higher NT-proBNP (p<0.001) than controls and patients only at risk for HF (Stage A). NT-proBNP showed a significant diagnostic accuracy in discriminating stage B (n=93) versus stage A patients (n=67, AUC=0.755 ± 0.038, p<0.001) and controls (AUC=0.834 ± 0.030, p<0.001).

CONCLUSION

Higher CRP and the presence of left ventricular diastolic dysfunction were independently associated with higher NT-proBNP. NT-proBNP might be used in RD as a marker of both disease activity and subclinical cardiac involvement.