Abstract
Left atrial function (LAF) is crucial to hemodynamics, but the effects of preload variation on its echocardiographic indices remain unclear. This study aimed to identify preload-independent phasic LA echocardiographic variables and to assess blood donor dogs as a hypovolemia model. Twenty-six healthy, client-owned dogs underwent transthoracic echocardiography before and after standardized blood donation. Phasic LA volumes and strain parameters were assessed, and a subgroup of dogs donating ≥ 10 mL/kg was also analyzed. After blood withdrawal, significant reductions were observed in maximum LA volume (p = 0.0350), LA ejection volume and LA ejection fraction (p = 0.0204), reservoir strain (p = 0.0149), and contractile strain (p = 0.0149), confirming their preload dependency. Conversely, minimum volume (p = 1.0000), pre-atrial contraction volume (p = 0.4373), and conduit strain (p = 0.2156) did not change significantly in the subgroup, indicating lower sensitivity to acute volume variation. These results demonstrate that different LA functional phases respond differently to preload changes and suggest that some parameters may be more stable for clinical interpretation under variable hemodynamic conditions. The blood donation model proved to be a practical and ethically acceptable method for assessing preload-dependent variables in conscious dogs.
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The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.
References
Matsumoto, A. Y. et al. Echocardiographic evaluation of left atrial function: physiological and clinical aspects. Arq. Bras. Cardiol. - Imagem Cardiovasc. 27, 87–96 (2014).
Marino, P. N., Degiovanni, A. & Zanaboni, J. Complex interaction between the atrium and the ventricular filling process: the role of conduit. Open. Heart. 6, e001042 (2019).
Blume, G. G. et al. Left atrial function: physiology, assessment, and clinical implications. Eur. J. Echocardiogr. 12, 421–430 (2011).
Genovese, D. et al. Load dependency of left atrial strain in normal subjects. J. Am. Soc. Echocardiogr. 31, 1221–1228 (2018).
Gottfridsson, P. et al. Left atrial contraction strain and controlled preload alterations, a study in healthy individuals. Cardiovasc. Ultrasound. 20, 4–9 (2022).
Coelho, M. R. et al. Evaluation of left atrial function in asymptomatic dogs with chronic myxomatous mitral valve disease: two-dimensional feature-tracking echocardiography and simpson’s monoplanar methods. Pesq Vet. Bras. 40, 188–196 (2020).
Savarino, P. et al. Left atrial volume and function in Cavalier King Charles spaniels at different ACVIM stages. Res. Vet. Sci. 180, 105428 (2024).
Paranjape, V. V., Henao-Guerrero, N., Menciotti, G. & Saksena, S. Volumetric evaluation of fluid responsiveness using a modified passive leg Raise maneuver during experimental induction and correction of hypovolemia in anesthetized dogs. Vet. Anaesth. Analg. 50, 211–219 (2023).
Paranjape, V. V., Henao-Guerrero, N., Menciotti, G. & Saksena, S. Performance of four cardiac output monitoring techniques vs. intermittent pulmonary artery thermodilution during a modified passive leg Raise maneuver in isoflurane-anesthetized dogs. Front. Vet. Sci. 10, 1238549 (2023).
Marshall, K. A. et al. Ultrasound measurements of the caudal Vena Cava before and after blood donation in 9 Greyhound dogs. Can. Vet. J. 59, 973–980 (2018).
Tréz, T. A. Considerações sobre o conceito Dos 3Rs e o potencial conflito com novas compreensões do animal experimental. Rev. Bras. Zoociências. 19, 97–113 (2018).
Kuo, K. W. & McMichael, M. Small animal transfusion medicine. Vet. Clin. North. Am. Small Anim. Pract. 50, 1203–1214 (2020).
Decloedt, A., Verheyen, T., Sys, S., De Clercq, D. & van Loon, G. Quantification of left ventricular longitudinal strain, strain rate, velocity, and displacement in healthy horses by 2-dimensional speckle tracking. J. Vet. Intern. Med. 25, 330–338 (2011).
McGraw, K. O. & Wong, S. P. Forming inferences about some intraclass correlation coefficients. Psychol. Methods. 1, 30–46 (1996).
Keene, B. W. et al. ACVIM consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs. J. Vet. Intern. Med. 33, 1127–1140 (2019).
Baron Toaldo, M. et al. Left atrial speckle tracking echocardiography in clinically healthy dogs: variability and prediction intervals. Vet. J. 270, 105577 (2021).
Thomas, W. P. et al. Recommendations for standards in transthoracic two-dimensional echocardiography in the dog and Cat. J. Vet. Intern. Med. 7, 247–252 (1993).
Hall, J. E. & Hall, M. E. Guyton and Hall Textbook of Medical Physiology. 14th ed. (Elsevier, Philadelphia, 2020).
Gan, G. C. H., Bhat, A., Chen, H. H. L., Fernandez, F., Byth, K., Eshoo, S. & Thomas, L. Determinants of left atrial reservoir strain: independent effects of left atrial volume and left ventricular global longitudinal strain. Echocardiography 37, 2018–2028 (2020).
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We would like to thank the Graduate Program in Veterinary Medicine at FMVZ-UNESP, Botucatu.
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Conceptualization, R.B.C. and M.L.G.L.; methodology, R.B.C., M.C.F.L. and A.A.L.S.; investigation, R.B.C.; formal analysis, M.H.T.; data curation, R.B.C.; writing—original draft preparation, R.B.C.; writing—review and editing, R.B.C., M.L.G.L., R.F. and C.J.L.R.; supervision, M.L.G.L.; statistical interpretation, R.B.C.; statistical analysis, M.H.T. All authors have read and agreed to the published version of the manuscript. This study have been deposited in the Unesp Intitucional Repository São Paulo State University, Unesp – Brazil in the accession repository link below:https://repositorio.unesp.br/entities/publication/2600cbd2-d495-4314-8221-58bb8a96683e.
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Cepinho, R.B., de Souza, A.A.L., Reyes, C.J.L. et al. Left atrial strain response to acute preload reduction in healthy dogs using a translational blood donation model. Sci Rep (2026). https://doi.org/10.1038/s41598-026-35086-4
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DOI: https://doi.org/10.1038/s41598-026-35086-4


