Plasma N-terminal pro-atrial natriuretic peptide predicts death after premature myocardial infarction, but not as well as radionuclide ejection fraction. A ten-year follow-up study.

OBJECTIVE

To assess N-terminal pro-atrial peptide (N-ANP) as a predictor of total and cardiac death in patients with previous premature myocardial infarction (MI).

DESIGN

In this prospective cohort study, we measured plasma N-ANP by ELIZA assays and ejection fraction (EF) by radionuclide ventriculography in a cohort of 247 patients (193 men and 54 women) who had had MI at a relatively young age (males: first MI at age < or =55; females <60).

RESULTS

After 10 years 44 patients had died, 36 from cardiac causes. After using a stepwise procedure to adjust for other prognostic factors (i.e. plasma total homocysteine (tHcy), C-reactive protein and age), the relative risk (RR) was 2.00 (95% confidence interval (CI) 1.05-3.80) (p = 0.03) for death of all causes and 2.32 (95% CI 1.19-4.55) (p=0.01) for cardiac death when the top quartile was compared to the three lower quartiles of N-ANP. When radionuclide EF entered the Cox model, N-ANP became insignificant as a predictor of mortality.

CONCLUSION

N-ANP was a significant predictor of total death and cardiac death in young survivors of MI, but radionuclide EF was a more independent prognostic variable.