Objective To evaluate mid-regional pro-adrenomedullin (MR-proADM) and mid-regional pro-atrial natriuretic peptide (MR-proANP) as prognostic biomarkers in a representative ‘real world’ cohort of patients with suspected acute coronary syndrome (ACS).

Design Prospective observational multicentre cohort study.

Setting Chest pain units of three major hospitals in Germany from 2007 to 2008.

Patients Patients presenting with signs and symptoms suggestive of an ACS.

Main outcome measures Primary end point was death or non-fatal myocardial infarction (MI), and secondary end point was death, non-fatal MI, stroke, need for coronary revascularisation, and hospital admission for cardiovascular cause or acute heart failure within 6 months after enrolment.

Results 1386 patients (male/female=920/466) were enrolled. Follow-up information was available for 97.8% of patients (median follow-up time 183 days). Forty-three patients reached the primary end point, and 132 the secondary end point. Patients who reached a primary end point had significantly higher MR-proANP (271 vs 101 pmol/l, p<0.001) and MR-proADM (0.86 vs 0.59 nmol/l, p<0.001) concentrations than those who did not. Cox regression analysis revealed a 2.55-fold risk of death or non fatal MI (95% CI 1.48 to 2.46, p<0.001) for an increment of the log-transformed MR-proANP concentration by 1 SD after adjustment for cardiovascular risk factors, and a 1.91-fold risk (95% CI 1.48 to 2.46, p<0.001) for MR-proADM. Both peptides could result in significant reclassification of patients when added to the Global Registry of Acute Coronary Events risk score, with an overall net reclassification improvement of 41.2% for MR-proADM and 35.7% for MR-proANP.

Conclusions MR-proADM and MR-proANP are predictors of future cardiovascular events in patients presenting with acute chest pain and might facilitate the choice of treatment in those patients complementary to established risk scores.