6.3.2 Biomarkers for Diagnosis: Recommendation Biomarkers: Recommendation for Diagnosis COR LOE Recommendation Comment/Rationale I A In patients presenting with dyspnea, measurement of natriuretic peptide biomarkers is useful to support a diagnosis or exclusion MODIFIED: 2013 acute and chronic recommendations have been combined into a diagnosis section. See Online Data Supplements A and B. Natriuretic peptide biomarker testing in the setting of chronic ambulatory HF provides incremental diagnostic value to clinical judgment, especially when the etiology of dyspnea is unclear.15 21 In emergency settings, natriuretic peptide biomarker levels usually have higher sensitivity than specificity and may be more useful for ruling out than ruling in HF.20 Although lower values of natriuretic peptide biomarkers exclude the presence of HF, and higher values have reasonably high positive predictive value to diagnose HF, clinicians should be aware that elevated plasma levels for both natriuretic peptides have been associated with a wide variety of cardiac and noncardiac causes (Table 2).38 41 6.3.3 Biomarkers for Prognosis or Added Risk Stratification: Recommendations Biomarkers: Recommendations for Prognosis COR LOE Recommendations Comment/Rationale I A Measurement of BNP or NT-proBNP is useful for establishing prognosis or disease severity in chronic HF.16,87 92 2013 recommendation remains current. 2017 ACC/AHA/HFSA Heart Failure Focused Update CLINICAL STATEMENTS AND GUIDELINES Figure 1. Biomarkers Indications for Use. Colors correspond to COR in Table 1. *Other biomarkers of injury or fibrosis include soluble ST2 receptor, galectin-3, and high- sensitivity troponin. ACC indicates American College of Cardiology; AHA, American Heart Association; ADHF, acute decom- pensated heart failure; BNP, B-type natriuretic peptide; COR, Class of Recommendation; ED, emergency department; HF, heart failure; NT-proBNP, N-terminal pro-B-type natriuretic peptide; NYHA, New York Heart Association; and pts, patients. 