Subclinical right ventricular dysfunction in intermittent and persistent mildly asthmatic children on tissue Doppler echocardiography and serum NT-proBNP: Observational study.

Background: Bronchial asthma may lead to pulmonary hypertension, right ventricular (RV) dysfunction, and cor pulmonale due to elevated afterload on the RV later in life. The aim of this study was to determine whether serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) might serve as a biomarker for detecting subclinical RV dysfunction using echocardiography during the early stages of bronchial asthma.

Methods: Sixty-eight pediatric patients with asthma (asthma group) and 69 age- and sex-matched healthy children (control group) were enrolled. The study was conducted in a tertiary woman and child diseases education and research hospital from January 2013 to December 2013. RV function (2-D and tissue-Doppler echocardiography), pulmonary function (spirometry) and serum NT-proBNP concentration were evaluated.

Results: Mean age was 10.5 ± 2.8 years in the asthma group and 10.2 ± 2.7 years in the control group (P = 0.522). RV diastolic function was significantly decreased in the asthma group (ratio of tricuspid lateral annular early diastolic peak velocity to tricuspid lateral annular late diastolic peak velocity [E'/A'], 1.29 ± 0.68 vs 1.74 ± 0.89, P = 0.001). RV myocardial performance index was significantly higher in the asthma group than in the control group (0.28 ± 0.06 vs 0.24 ± 0.07, respectively; P = 0.003). Finally, serum NT-proBNP concentration was significantly higher in the asthma group than in the control group (292.3 ± 142.2 pg/mL vs 208.2 ± 70.1 pg/mL, respectively; P = 0.003).

Conclusion: Increased serum NT-proBNP is associated with subclinical RV dysfunction in asthmatic children. RV function is significantly affected in children with bronchial asthma.