Effect of posture on heart rate and cardiac axis of mice
Mohan, M.; Anandh, B.; Thombre, D.P.; Surange, S.G.; Chakrabarty, A.S.
Indian Journal of Physiology and Pharmacology 31(3): 211-217
1987
ISSN/ISBN: 0019-5499 PMID: 3429031 Document Number: 294618
Effect of change in body posture on cardiac electrical axis has not been well documented. Hence the present work was undertaken to study the effect of passive head-up and head-down postures on ventricular QRS axis and heart rate of anesthetised mice. During head-up posture, there was a statistically significant (P less than 0.02) increase in heart rate whereas during head-down posture, the heart rate decreased insignificantly. These changes in heart rate can be explained on the basis of synus and aortic nerve mediated baroreceptor reflexes. Ventricular QRS axis showed a significant increase (P less than 0.02) during head-up posture and an insignificant decrease during head-down posture. A change in the posture is likely to produce a change in anatomical orientation of heart within the thorax resulting in alteration of electrical axis of the heart.