Predictive value of NT-pro BNP after acute myocardial infarction: relation with acute and chronic infarct size and myocardial function.

AIM OF THE STUDY: We sought to assess the relation of N-terminal brain natriuretic peptide (NT-pro BNP) determined on day 3 after onset of acute myocardial infarction (AMI) symptoms with acute and chronic infarct size and functional parameters assessed by cardiac magnetic resonance (CMR) imaging. Furthermore, we wanted to investigate its predictive value for recovery of myocardial function.

METHODS: CMR was performed in 49 consecutive patients within 6 days and in a subgroup 4 (n = 27) and 12 (n = 22) months after first acute ST-elevation AMI and successful primary angioplasty. NT-pro BNP was measured in the subacute phase at 66 ± 8 h after onset of symptoms.

RESULTS: Log-transformed NT-pro BNP (lgNT-pro BNP) significantly correlated with infarct size in % of left ventricular myocardial mass (r = 0.59 to 0.64; p < 0.004), with ejection fraction (EF) (r = -0.49 to -0.55; p < 0.004) as well as with segmental wall thickening (SWT, mm) (r = 0.41 to -0.52; p < 0.04) at any time of assessment. Multiple linear regression analysis revealed baseline EF and lgNT-pro BNP to predict global functional recovery. Patients with NT-pro BNP concentrations <the mean level of 1115 pg/ml significantly improved in EF and SWT (all p < 0.02) during the study period, whereas patients with NT-pro BNP >1115 pg/ml did not show significant functional recovery (all p = NS).

CONCLUSION: NT-pro BNP on day 3 after admission correlates with acute and chronic infarct size and myocardial function after AMI. Global and regional myocardial function did not recover in patients with higher NT-pro BNP (>1115 pg/ml) during subacute phase of AMI.