Abstract: Echocardiographic measurements are important prognostic indicators but might be influenced by heart rate and blood pressure. This is particularly important when comparing repeated examinations. Objective: To determine the effect of physiological stress at mildly increased heart rates and pharmacological challenge using IV administration of N-butylscopolammonium bromide and metamizol sodium on heart rate, blood pressure, and echocardiographic measurements. Methods: Twenty healthy Warmblood horses. Methods: Randomized crossover study. Horses were examined echocardiographically by 2-dimensional, M-mode, pulsed wave (PW) Doppler, and PW tissue Doppler imaging with simultaneous ECG recording and noninvasive blood pressure measurements during rest, physiological stress, and pharmacological challenge. Cardiac dimensions and functions were measured by a blinded observer. Data were analyzed using repeated-measures analysis of variance. Results: Mean heart rate and arterial blood pressure were significantly higher during physiological stress (46 ± 2 bpm, 93 ± 16 mm Hg) and pharmacological challenge (62 ± 13 bpm, 107 ± 17 mm Hg) compared with rest (34 ± 3 bpm, 86 ± 12 mm Hg; P < .05). Compared with rest, physiological stress resulted in increased left atrial fractional area change (34.3 ± 7.5 vs 27.3 ± 5.1%; P = .01) and left ventricular late diastolic radial wall motion velocity (13 ± 3 vs 10 ± 2 cm/s; P = .01) but had no significant effect on most other echocardiographic variables. Compared with rest, pharmacological challenge led to significantly decreased left atrial and diastolic ventricular dimensions (left ventricular internal diameter: 10.3 ± 0.9 vs 10.7 ± 0.8 cm; P = .01), increased aortic and pulmonary diameters, and ventricular wall thickness. Conclusions: Physiological stress at mildly increased heart rates significantly enhanced atrial pump function. Larger heart rate and blood pressure increases during pharmacological challenge resulted in altered cardiac dimensions. This should be taken into account when evaluating echocardiographic measurements at increased heart rates.
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The research shows how stress, both physiological and through drug-induced challenges, impacts the heart rate, blood pressure, and echocardiographic measurements in healthy Warmblood horses. It reveals that changes in heart rate and blood pressure significantly influence certain cardiac measurements, which need to be considered in a veterinary context.
Research Methodology
The researchers studied 20 healthy Warmblood horses, conducting a randomized crossover study to gather comprehensive and reliable data.
A variety of techniques were used to study these horses, including 2-dimensional, M-mode, pulsed wave (PW) Doppler, and PW tissue Doppler imaging. These were measured alongside an ECG recording and noninvasive blood pressure measurements.
The researchers tested these horses under rest conditions, physiological stress, and a pharmacological challenge using N-butylscopolammonium bromide and metamizol sodium.
All resulting cardiac dimensions and functions were measured by an impartial observer and analyzed using repeated-measures analysis of variance.
Research Findings
During both physiological stress and the pharmacological challenge, the horses’ mean heart rate and arterial blood pressure significantly increased when compared with rest.
Physiological stress resulted in an increase in left atrial fractional area change and left ventricular late diastolic radial wall motion velocity. However, most other echocardiographic variables remained unaffected.
The pharmacological challenge resulted in decreased left atrial and diastolic ventricular dimensions, increased aortic and pulmonary diameters, and ventricular wall thickness.
Conclusion
The research shows how stress, both physiological and pharmacological, can impact cardiac measurements in horses. Specifically, physiological stress with mildly increased heart rates significantly enhanced atrial pump function.
Moreover, larger heart rate and blood pressure increases during pharmacological challenge resulted in altered cardiac dimensions.
Therefore, when evaluating echocardiographic measurements at increased heart rates, these factors should be considered carefully.
Cite This Article
APA
Dufourni A, Buschmann E, Vernemmen I, Van Steenkiste G, van Loon G, Decloedt A.
(2024).
Effect of physiological and pharmacological stress on heart rate, blood pressure, and echocardiographic measurements in healthy Warmblood horses.
J Vet Intern Med.
https://doi.org/10.1111/jvim.16967
Equine Cardioteam Ghent University, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Buschmann, Eva
Equine Cardioteam Ghent University, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Vernemmen, Ingrid
Equine Cardioteam Ghent University, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Van Steenkiste, Glenn
Equine Cardioteam Ghent University, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
van Loon, Gunther
Equine Cardioteam Ghent University, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Decloedt, Annelies
Equine Cardioteam Ghent University, Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Gehlen H, Kroker K, Deegen E, Stadler P. Einfluss von Detomidin auf echokardiographische Funktionsparameter und kardiale Hämodynamik bei Pferden mit und ohne Herzgeräusch.. Schweiz Arch Tierheilkd 2004;146(3):119-126.
Gehlen H, Marnette S, Stadler P. Stress echocardiography in warmblood horses: active stress induction by treadmill and longing exercise.. Pferdeheilkunde 2005;21(4):303-310.
Gehlen H, Becker J, Deegen E, Stadler P. Veränderung echokardiographischer Funktionsparameter unter Dobutaminwirkung bei Warmblutpferden mit und ohne Herzgeräusch.. Vet Med 2004;91:103-111.
Gehlen H, Marnette S, Stadler P. The influence of adrenaline on echocardiographic parameters of left ventricular function in the horse.. Equine Comp Exerc Physiol 2005;2(2):89-96.
Verheyen T, Decloedt A, De Clercq D, Deprez P, Sys S, van Loon G. Electrocardiography in horses, part 1: how to make a good recording.. Vlaams Diergeneeskd Tijdschr 2010;79(5):331-336.
Bland M. Clinical measurement.. In: Bland M, ed. An Introduction to Medical Statistics. 4th ed. Oxford: Oxford University Press; 2015:313-346.
Piotrowski G, Goch A, Wlazłowski R, Gawor Z, Goch JH. Non-invasive methods of atrial function evaluation in heart diseases.. Med Sci Monit 2000;6(4):827-839.
Pagel PS, Kehl F, Gare M, Hettrick DA, Kersten JR, Warltier DC. Mechanical function of the left atrium: new insights based on analysis of pressure-volume relations and Doppler echocardiography.. Anesthesiology 2003;98(4):975-994.
Yu CM, Sanderson JE. Right and left ventricular diastolic function in patients with and without heart failure: effect of age, sex, heart rate, and respiration on Doppler-derived measurements.. Am Heart J 1997;134(3):426-434.
Disatian S, Bright JM, Boon J. Association of age and heart rate with pulsed-wave Doppler measurements in healthy, nonsedated cats.. J Vet Intern Med 2008;22(2):351-356.
Covella M, Milan A, Totaro S. Echocardiographic aortic root dilatation in hypertensive patients: a systematic review and meta-analysis.. J Hypertens 2014;32(10):1928-1935.
Vizzardi E, Maffessanti F, Lorusso R. Ascending aortic dimensions in hypertensive subjects: reference values for two-dimensional echocardiography.. J Am Soc Echocardiogr 2016;29(9):827-837.
Farasat SM, Morrell CH, Scuteri A. Do hypertensive individuals have enlarged aortic root diameters? Insights from studying the various subtypes of hypertension.. Am J Hypertens 2008;21(5):558-563.
Mertens HM, Mannebach H, Trieb G, Gleichmann U. Influence of heart rate on systolic time intervals: effects of atrial pacing versus dynamic exercise.. Clin Cardiol 1981;4(1):22-27.
Robinson S, Ring L, Augustine DX. The assessment of mitral valve disease: a guideline from the British Society of Echocardiography.. Echo Res Pract 2021;8(1):G87-G136.