Atrial natriuretic factor and sympathetic activation in human heart failure. 
The neurohormonal changes occur early, have important prognostic value, and may play a role in the evolution and progression of heart failure in man.  Atrial natriuretic factor (ANF) is a natriuretic and vasorelaxant peptide.  Previous studies indicated that plasma ANF provides prognostic information and, ANF levels closely related to both severity of disease and catecholamine levels but, it is still unclear if high circulating levels of ANF, which are present in heart failure constantly, may be to correlate with sympathetic nervous activity in man.  Thus, the aim of the present study was to investigate the relations between the release of ANF and the sympathetic system in human heart failure.  We studied 18 patients with heart failure (CHF) and a control Group (n = 14) of healthy subjects.  To induce adrenergic activation in physiologic way patients were underwent to a low-exercise by cycle-ergometer in supine position.  Blood was collected at rest, and immediately after exercise for determination of plasma levels of ANF, norepinephrine and epinephrine levels.  ANF values at rest were 35.9 +/- 19.2 pg/ml in controls and 190.7 +/- 34.2 pg/ml (p < 0.001 vs controls) in CHF patients.  As well norepinephrine levels showed higher values in patients (295.7 +/- 47.8 pg/ml), than in normal subjects (143.5 +/- 33.3 pg/ml; p < 0.01).  In CHF patients epinephrine levels were 100.1 +/- 21.2 pg/ml (p < 0.01 vs controls).  ANF levels were in normal subjects 87.9 +/- 19.2 pg/ml (p < 0.01 vs rest) after exercise.  In CHF patients ANF values were 275.3 +/- 59.8 pg/ml; p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)