Cardiovascular Biomarkers

The value of circulating biomarkers to care for patients with cardiovascular disease has grown significantly over the last few decades. The majority of clinical data focus on the use of natriuretic peptides (NPs) for the diagnosis, prognosis, and management of patients with heart failure (HF) and troponin measurements in patients with suspected or proven acute coronary syndrome (ACS). Part of the reason for the slow adoption of biomarkers beyond these two classes has been limitation in the optimal modes of application of new assays. Future studies are needed to clarify the use of biomarkers, with the ultimate goal of simplifying the diagnosis, prognosis, and patient care of complex cardiovascular conditions. This chapter reviews the use of established biomarkers for HF, ACS, and atrial fibrillation (AF). Tables include a summary of emerging and established cardiovascular biomarkers, characteristics of B-type natriuretic peptide and amino-terminal pro-B-type natriuretic peptide, cutoff points for NP measurement, differential diagnosis of elevated NP concentrations, biomarkers in HF with preserved ejection fraction, summary of NP management trials, third universal definition of myocardial infarction, and guidelines for recommendations of biomarkers in HF. Figures depict the various causes of NP release, the complex mechanism of troponin release in patients with HF, the ischemic and nonischemic etiologies of troponin release, timing of biomarker release during myocardial infarction, and the biomarkers involved in the pathogenesis of AF. Algorithms demonstrate evaluating outpatients with dyspnea in the clinic using NPs in their workup and the use of troponin to assist with determining an appropriate management strategy for a patient with ACS. This review contains 7 highly rendered figures, 8 tables, and 202 references.