The third heart sound for diagnosis of acute heart failure.

Dyspnea is a common presenting complaint in the emergency department (ED). Rapid identification of heart failure as the etiology leads to early implementation of targeted therapies. Although having only intermediate sensitivity, the S3 is a highly specific finding among older adults with heart failure. Identification of an S3 by routine auscultation can be problematic given the chaotic and noisy ED environment, patient comorbid conditions, and intolerance of ideal positioning for auscultation. Technologies using computerized analysis of digitally recorded heart tones have recently been developed to aid the clinician with bedside detection of abnormal heart sounds. Data using these technologies and their applications in the ED are reviewed as well as implications for future use and research.