Objectives: The aim of this study was to determine the prognostic utility of midregion proadrenomedullin (MR-proADM) in all patients, cardiac and noncardiac, presenting with acute shortness of breath. Background: The recently published BACH (Biomarkers in Acute Heart Failure) study demonstrated that MR-proADM had superior accuracy for predicting 90-day mortality compared with B-type natriuretic peptide (area under the curve: 0.674 vs. 0.606, respectively, p 3.28), and it was also superior to all other biomarkers. MR-proADM added significantly to the best clinical model (bootstrap-corrected c index increase: 0.775 to 0.807; adjusted standardized hazard ratio: 2.59; 95% confidence interval: 1.91 to 3.50; p