[Measurement of human brain natriuretic peptide in patients with Chagas' disease].
OBJECTIVE
To measure the serum levels of brain natriuretic peptide (BNP) in patients with chronic chagasic heart disease and in individuals with positive serology for Chagas' disease and no heart impairment, and to correlate the serum BNP levels with the degree of cardiac impairment, cardiac dimensions, presence of a pacemaker, and ejection fraction.


METHODS
Serum BNP concentrations were determined by use of the Triage-BNP Test produced by BIOSITE. Serum BNP was assessed in 25 patients from the Chagas' disease outpatient clinic of the Hospital Universitario Oswaldo Cruz, who were divided into 2 groups as follows: 1) G1--comprising 13 asymptomatic patients with positive serology for Chagas' disease and no heart disease detectable on electrocardiography, chest X-ray, and echocardiography; and 2) G2--comprising 12 patients with Chagas' disease and heart impairment.


RESULTS
Significantly more elevated BNP levels were detected in the chagasic patients with cardiac impairment: (G1=4.4 +/-4.4 pg/ml, G2=293.0+/-460.2 pg/ml); (P<0.01). In the 2 groups, the serum levels of BNP correlated neither with age nor with sex. The levels were directly proportional to functional class and cardiac area on chest X-ray. Although a trend towards an increment in systolic function impairment was observed, no linear correlation with the ejection fraction on echocardiography occurred. The presence of definitive pacemaker and electrocardiographic alterations did not change the serum BNP levels.


CONCLUSIONS
Asymptomatic individuals with a positive serology for Chagas' disease and no evidence of ventricular dysfunction have serum BNP levels similar to those of the general population.
Melo
Railton Bezerra de
RB
UFP, Recife, PE.
Parente
Giordano Bruno de Oliveira
GB
Victor
Edgar Guimarães
EG
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002598:Chagas Cardiomyopathy / Q000097:blood; D014355:Chagas Disease / Q000097:blood*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012720:Severity of Illness Index
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain