Cardiac peptides differ in their response to exercise - Implications for patients with heart failure in clinical practice

Aims Cardiac peptides have diagnostic and prognostic value in heart failure . Their plasma concentrations, however, are sensitive to rapid changes in h aemodynamics. As blood sampling under standard conditions is not feasible i n clinical practice, it is important to know which peptides are most resist ant to change. Therefore, the present study investigated the differences in response to exercise between atrial natriuretic peptide, N-terminal proatr ial natriuretic peptide, brain natriuretic peptide and the recently identif ied N-terminal probrain natriuretic peptide. Methods and Results Fifty-two patients with chronic heart failure performed a symptom-limited graded bicycle exercise. Blood samples for determination of plasma concentrations of cardiac peptides were drawn at rest and at pea k exercise. There was a significant difference in percentage increase in re sponse to exercise between the four peptides (P < 0.0001). N-terminal proat rial natriuretic peptide increased less than atrial natriuretic peptide (5 +/- 18% vs 59 +/- 58%; P < 0.0001). The difference in increase between N-te rminal probrain natriuretic peptide and brain natriuretic peptide was less distinct but: still significant (24 +/- 24% vs 38 +/- 52%, P < 0.05). Conclusions Both N-terminal proatrial natriuretic peptide and N-terminal pr obrain natriuretic peptide increased less in response to exercise than thei r C-terminal counterparts. This implies that the circumstances under which blood sampling for measurements of N-terminal proatrial natriuretic peptide and N-terminal probrain natriuretic peptide should be performed are more f avourable than the blood sampling conditions for atrial natriuretic peptide and brain natriuretic peptide.