Serum NT pro-BNP: relation to systolic and diastolic function in cardiomyopathies and pericardiopathies

BACKGROUND: NT pro-BNP is a marker of systolic and diastolic dysfunction. OBJECTIVE: To determine NT pro-BNP levels in patients with chagasic, hypertrophic, and restrictive heart diseases, as well as with pericardial diseases, and their relation to echocardiographic measurements of systolic and diastolic dysfunction. METHODS: A total of 145 patients were divided into the following groups: 1) Chagas’ heart disease (CHD) – 14 patients; 2) hypertrophic cardiomyopathy (HCM) – 71 patients; 3) endomyocardial fibrosis (EMF) – 26 patients; 4) pericardial effusion (PE) – 18 patients; and 5) constrictive pericarditis (CP) – 16 patients. The control group was comprised of 40 individuals with no heart disease. The degree of myocardial impairment and pericardial effusion were assessed by two-dimensional echocardiography and the degree of restriction by pulsed Doppler transmitral flow. The diagnosis of CP was confirmed through magnetic resonance imaging. NT pro-BNP levels were determined through electrochemiluminescence immunoassay. RESULTS: NT pro-BNP was increased (p < 0.001) in CHD (median = 513.8 pg/ml), HCM (median = 848 pg/ml), EMF (median = 633 pg/ml), CP (median = 568 pg/ml), and PE (median = 124 pg/ml), when compared with the control group (median = 28 pg/ml). No statistically significant differences were found between CP and EMF (p = 0.14). In the hypertrophic group, NT pro-BNP was correlated with left atrial size (r = 0.40; p < 0.001) and with E/Ea ratio (p < 0.01). In the restrictive group, there was a trend of correlation with E-wave peak velocity (r = 0.439; p = 0.06). CONCLUSION: NT pro-BNP is increased in the different cardiomyopathies and pericardial diseases and is correlated with the degree of systolic and diastolic dysfunction.