Assessing the Association Between Cardiovascular Acoustic Biomarkers and Heart Failure: A Systematic Literature Review

OBJECTIVES: Heart failure (HF) outcomes remain poor—impacting patients, caregivers, and healthcare systems. Hence, options to improve prediction and monitoring are needed. Cardiovascular acoustic biomarkers (CABs) may represent valuable noninvasive means to assess incumbent HF. We conducted a systematic literature review (SLR) to evaluate associations between CABs and HF outcomes.

METHODS: We searched EMBASE and MEDLINE for studies published between January 1, 2013–March 16, 2023, evaluating CABs in patients with HF. Gray literature (eg, congress and pre-print publications) searches were included. Two reviewers independently examined all articles; a third resolved conflicts. Data were extracted from articles meeting inclusion criteria.

RESULTS: In total, 3074 records were screened, 73 full-text articles were assessed for eligibility, and 28 publications were included. Third heart sound (S3) and electromechanical activation time (EMAT) were the most-used CABs for monitoring HF. Five of 6 publications reported significantly increased S3 presence in patients with worsening HF. Ten studies reported associations between clinical outcomes and S3 strength or amplitude (n=5) and/or presence (n=6) in patients with HF. Of 5 studies, 4 reported prolonged EMAT or its derivatives in patients with more severe HF. Six studies reported associations between EMAT and clinical outcomes of myocardial infarction (n=1) or HF (n=5). Studies reporting first heart sound amplitude, fourth heart sound presence, left ventricular ejection time, and systolic dysfunction index were limited.

CONCLUSIONS: Based on the reported associations between CABs and HF outcomes from studies in this SLR, the presence of S3 or prolonged EMAT or its derivatives may predict adverse cardiac events. Detection of these CABs in a remote setting could offer clinical and societal benefits. While these findings emphasize that EMAT and S3 may be useful in diagnosing and monitoring HF, additional studies designed to test the predictive power of these, and other less well-characterized CABs, are needed.