Brain natriuretic peptide in patients with heart failure:relation with left ventricular function and exercise breathness severity

Objective Rapid heart rate and diastolic dysfunction are common in patients with early stage of heart failure.Exercise breathness is main symptom in such patients.Atrial natriuretic peptide(ANP)is a cardiac hormon that secreated by increased atrial stretch.Positive correlation between plasma ANP concentrations and atrial pressures have been found in cardiac patients and healthy subjects.Brain natriuretic peptide (BNP) is released primarily in respons to ventricular wall stress.The aim of this study,therefore,was to determine the left ventricular ejection and filling function associated with higher ANP and BNP levels in patients with heart failure and to correlate exercise BNP with VE/VCO2 slop assessed by cardiopulmonary exercise test.Methods 30 normal subjects and 32 patients underwent complete m-mode and cross sectional echocardiography and Doppler ultrasound examination.Aortic flow velocity and diastolic flow velocity was recorded by pulsed wave Doppler.The following diastolic variables were measured:peak left ventricular ejection time and filling time and velocity.Peak early mitral filling velocity (E wave),peak atrial filling velocity (A wave) and left ventricular filling time,E/A ratio were derived.ANP and BNP were assessed by radioimmunoassy at same time.Results In 32 patients with heart failure,18 patients had ischemic heart disease, 14 patients had nonischemic heart disease. Resting heart rate in patients with heart failure were higher than normal subjects(P0.05).Compared with normal subjects,left ventricular dimension increased(P0.05) and shortening fraction reduced (P0.05), stroke distance reduced(P0.05).Early diastolic filling velocity did not show significant difference(P0.05). 2.ANP significantly correlated with BNP in patients with heart failure(r=0.73,P0.01),There are no significant difference between end-diastolic dimension6.5 cm and end-diastolic dimension6.5 cm in both ANP and BNP concentration(P0.05). 3.Resting heart rate correlated with BNP (r=-0.67, P0.01). BNP did not correlate with left ventricular size and atrial size. But significant correlated with left ventricular ejection time (r=0.71,P0.01) and filling time(r=-0.41,P0.01) as well as E/A ratio(r=0.62,P0.01).ANP only correlated with E/A ratio(r=0.55,P0.01).4.Exercise BNP correlated with VE/VCO2 slop (r=0.70,P0.01) by cardiopulmonary exercise test.Conclusions ANP and BNP were elevated in early stage heart failure patients due to ischemic heart disease and dilated cradiomyopathy,significant correlated with cardiac function by Doppler echocardiogram.Exercise BNP related with VE/VCO2 slop in cardiopulmonary exercise test in such patients.