Studying some essential cardiovascular hemodynamic classes* from Giraffe 

Studying some essential cardiovascular hemodynamic classes* from Giraffe 

July 1, 2024 by dr s venkatesan

*This publish might not be meant for cardiology fellows however for younger college students of drugs

Have you ever ever considered how a Giraffe’s coronary heart can pump blood to the summit of a prolonged neck and perfuse the mind?

In contrast to a blue whale which has an enormous coronary heart, a Giraffe’s coronary heart is just not as massive as one would Think about, A Giraffe’s coronary heart weighs .5 to . 6 % of whole physique mass. If the common weight of a Giraffe is 650kg, the center could be round 3 kg.It’s nearly in related proportion to the human coronary heart.( In a 70 kg man coronary heart weighs about 350 grams). Nonetheless, it generates extra energy and strain, as much as 300mmhg BP. 

Classes from Giraffe coronary heart

1. Though the center is just not massive, the partitions are thicker many instances instances. In easy phrases it mimics a coronary heart of Hypertrophic cardiomyopathy, which we all know has brisk ejection. The mix of thick wall and a small cavity attenuates the wall stress considerably .This permits the center to pump a superb stroke quantity, excessive into the mind positioned greater than 5 to eight ft above the center. What a exceptional phenomenon.(Laplace regulation executed within the finest method in biology) *Laplace regulation states , the wall stress is straight proportional to the cavity diameter, not directly associated to the thickness of the wall

2.We are able to additionally perceive the rules of the administration of cardiomyopathy from a Giraffe’s coronary heart. If the ventricles assume a tubular morphology, optimum power and cardiac energy might be accrued. This varieties the premise behind the ventricular discount and reconstruction surgical procedure for Ischemic dilated cardiomyopathy.(Batisda process and so forth)

3.The innovators and engineers of new-age mechanical help methods might be taught just a few essential insights from these distinctive and humble animal beings. (Lets take into consideration,axial pumps in ascending Aorta in sequence with LV. An Aortic Impella machine, that’s distal to the aortic valve and devoid of LV-related points. )

With every systole, blood has to journey a most of as much as 8 ft up, with sufficient energy on the similar time to not injure the vessel wall

When bending the alternative occurs, and the valves in each arterial and venous methods come to guard by dampening the movement and avoiding congestion.

 An alternate speculation: Siphon impact in cranial circulation 

Some imagine the center is assisted by an alternate mechanism within the Giraffes. The carotid artery might act like a siphon from the center. Siphons can defy gravity. Is it a actuality in dwelling beings? How is that this attainable? I’m not clear. In that case, that may be tried in human experiments on cerebral insufficiency.

 Ultimate message 

Each dwelling and (even non-living issues) surrounding us, hold sending some silent scientific messages. The hemodynamic of the Giraffe’s vascular system is an effective physiologic mannequin of circulation, that defy gravity. It reinforces a fundamental, however essential studying level* {that a} tubular & cylindrical coronary heart can generate extra energy than a big globular one.

Reference

1.Graham Mitchell Shane Ok. Maloney, Duncan Mitchell  The origin of imply arterial and jugular venous blood pressures in giraffes The Journal of Experimental Biology 209, 2515-2524

 2.Aalkjær C, Wang T. The cardiovascular challenges in giraffes. J Muscle Res Cell Motil. 2023 Jun;44(2):53-60. doi: 10.1007/s10974-022-09626-0. Epub 2022 Jul 25. PMID: 35879488.

3.Aalkjær C, Wang T. The Outstanding Cardiovascular System of Giraffes. Annu Rev Physiol. 2021 Feb 10;83:1-15. doi: 10.1146/annurev-physiol-031620-094629. Epub 2020 Nov 9. PMID: 33167747.