Work

Associations of Electromechanical Activation Time With Cardiac Structure and Function and Clinical Outcomes

Year: 2025

Type: article

Abstract: BACKGROUND: The electromechanical activation time (EMAT) measured by acoustic cardiography is the time between QRS onset and the first heart sound. Increased EMAT is associated with a reduced left ventricular ejection fraction (LVEF). OBJECTIVES: The objective of the study was to determine whether EMAT has utility as a cardiovascular (CV) screening test in the community. METHODS: Participants (n = 3,401) in Dallas Heart Study-2 had acoustic cardiography, cardiac magnetic resonance imaging, and blood sampling at baseline. Clinical outcomes, including a composite of CV death/heart failure (HF) hospitalization or major adverse clinical events (CV death, HF hospitalization, nonfatal myocardial infarction, stroke, and atrial fibrillation), were ascertained after a median follow-up of 12.4 years. Multivariable models evaluated whether EMAT was associated with cardiac structure and function and clinical outcomes. Discrimination for reduced LVEF (<55%) was assessed by C-statistics. RESULTS: Higher continuous EMAT was independently associated with a lower LVEF (P < 0.001) and greater left ventricular end-diastolic volume (P = 0.04). However, an increased EMAT had poor discrimination for reduced LVEF (C-statistic = 0.52), was inferior to N-terminal pro-B-type natriuretic peptide (NT-proBNP) (C = 0.59, P < 0.01 vs EMAT), and did not improve discrimination beyond NT-proBNP alone (P = 0.90). Baseline EMAT was associated with CV death/HF hospitalization (HR: 1.3; 95% CI: 1.2-1.4; P < 0.001) and with major adverse clinical events (HR: 1.2; 95% CI: 1.1-1.4; P < 0.001) in models adjusted for age, race, and sex, but these associations did not persist after additional adjustment for NT-proBNP (P > 0.10 for both). CONCLUSIONS: In a community cohort, an increased EMAT was associated with a lower LVEF and adverse prognosis but had poor discriminatory capacity for the former and was not independent of NT-proBNP for the latter.

Source: JACC Advances

DOI: 10.1016/j.jacadv.2025.102371