Serum NT-proBNP could signal asymptomatic myocardial fibrosis

Elevated serum levels of the N-terminal pro-B-type peptide (NT-proBNP) seems to be an indicator of histopathologically proven myocardial fibrosis even among apparently healthy individuals, a recent study has found.

The researchers enrolled 63 autopsies (mean age 82 years, 52 percent men) without apparent heart disease who had available serum NT-proBNP measurements within 6 years before death. The percentage areas of myocardial fibrosis in four cardiac segments were measured for each participant, and its correlation with blood chemistry was assessed.

Person’s correlation analysis showed a significant and positive association between myocardial fibrotic area and serum NT-proBNP levels (r, 0.49, 95 percent confidence interval [CI], 0.28–0.66; p<0.001).

In accordance with the guidelines of the European Society of Cardiology, NT-proBNP measurements were divided into three categories: <125, 125–229, and ≥300 pg/mL. The age- and sex-adjusted myocardial fibrotic area increased significantly and linearly across these categories (p<0.001).

Moreover, after removing 13 cases with NT-proBNP levels ≥900 pg/mL, linear mixed models confirmed that for every 1-unit increment in the natural log-transformed serum NT-proBNP concentrations, the percentage area of myocardial fibrosis reflected a corresponding and significant increase of 1.10 units (95 percent CI, 0.30–1.90).

“These findings highlight the possibility that serum NT-proBNP measurement could be used for the detection of asymptomatic myocardial fibrosis and enhance our understanding of the association between asymptomatic elevated serum NT-proBNP and the development of heart failure and cardiovascular mortality,” the researchers said.