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Animals : an open access journal from MDPI2025; 15(13); 1993; doi: 10.3390/ani15131993

Application of Acoustic Cardiography in Assessment of Cardiac Function in Horses with Atrial Fibrillation Before and After Cardioversion.

Abstract: Left atrial mechanical dysfunction is common in horses following the treatment of atrial fibrillation (AF). This study aimed to evaluate the use of an acoustic cardiography monitor (Audicor) in quantifying cardiac mechanical and hemodynamic function in horses with AF before and after treatment and to correlate these findings with echocardiographic measures. Twenty-eight horses with AF and successful transvenous electrical cardioversion were included. Audicor recordings with concomitant echocardiographic examinations were performed one day before, one day after, and two to seven days after cardioversion. Key variables measured by Audicor included electromechanical activating time (EMAT), heart rate-corrected EMATc, left ventricular systolic time (LVST), heart rate-corrected LVSTc, systolic dysfunction index (SDI), and intensity and persistence of the third and fourth heart sound (S3, S4). A repeated-measures ANOVA with Tukey's test was used to compare these variables over time, and linear regression and Bland-Altman analyses were applied to assess associations with echocardiographic findings. Following conversion to sinus rhythm, there was a significant decrease in EMATc and LVSTc ( < 0.0001) and a significant increase in LVST ( = 0.0001), indicating improved ventricular systolic function, with strong agreement between Audicor snapshot and echocardiographic measures. However, S4 quantification did not show clinical value for assessing left atrial function after conversion.
Publication Date: 2025-07-07 PubMed ID: 40646892PubMed Central: PMC12248963DOI: 10.3390/ani15131993Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The plain language overview: This research studies how a device called an acoustic cardiography monitor can assess heart function in horses suffering from atrial fibrillation, a condition affecting heart rhythms, before and after treatment. The results showed significant improvements in various parameters indicating better heart function, and a strong correlation was observed between the results provided by the device and traditional heart imaging techniques.

Introduction and Purpose of the Research

  • The research aims to test the usefulness of an acoustic cardiography monitor, Audicor, as a tool for measuring mechanical and blood flow characteristics of the heart in horses affected by atrial fibrillation (AF), both before and after treatment.
  • This experiment is conducted with an additional goal of relating the results derived from the Audicor device to those obtained through standard echocardiography methods.

Methodology of the Study

  • The study involves 28 horses diagnosed with AF and successfully treated via transvenous electrical cardioversion, a procedure used to restore normal heart rhythm.
  • Each horse underwent an Audicor recording and echocardiography one day before, one day after, and two to seven days after the cardioversion treatment.
  • Different variables were measured using Audicor, such as electromechanical activating time (EMAT), heart rate-adjusted EMATc, left ventricular systolic time (LVST), heart rate-adjusted LVSTc, the systolic dysfunction index (SDI), and intensity and duration of the third and fourth heart sounds (S3, S4).
  • A statistical method (repeated-measures ANOVA with Tukey’s test) was used for comparison of variables over time, while linear regression and Bland-Altman methods were employed to study correlations with echocardiographic findings.

Major Findings and Conclusions

  • The research found that after successful conversion to a normal sinus rhythm, there was a significant drop in EMATc and LVSTc, suggesting better function of the heart’s ventricles.
  • There was a notable increase in LVST, further indicating improvements in ventricular systolic function.
  • A significant agreement was found between the results from Audicor and echocardiography, ascertaining the reliability of Audicor in such cardiac evaluations.
  • However, the study found that the measure of the fourth heart sound (S4) did not prove clinically useful in determining the function of the left atrium after conversion to sinus rhythm.

Cite This Article

APA
Schneider MJ, Piotrowski IL, Junge HK, van Steenkiste G, Vernemmen I, van Loon G, Schwarzwald CC. (2025). Application of Acoustic Cardiography in Assessment of Cardiac Function in Horses with Atrial Fibrillation Before and After Cardioversion. Animals (Basel), 15(13), 1993. https://doi.org/10.3390/ani15131993

Publication

ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 15
Issue: 13
PII: 1993

Researcher Affiliations

Schneider, Mélodie J
  • Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland.
Piotrowski, Isabelle L
  • Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland.
Junge, Hannah K
  • Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland.
van Steenkiste, Glenn
  • Equine Cardioteam Ghent, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
Vernemmen, Ingrid
  • Equine Cardioteam Ghent, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
van Loon, Gunther
  • Equine Cardioteam Ghent, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
Schwarzwald, Colin C
  • Clinic for Equine Internal Medicine, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland.

Grant Funding

  • No grant number / Stiftung fu00fcr Herz- und Kreislaufkrankheiten, Hergiswil, Switzerland (2019)

Conflict of Interest Statement

The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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