Each aerobic organism has a certain mechanism, commonly a kind of heart, of specific volume capacity, to force "blood" to circulate, in order to provide food and oxygen to its vital organs. I wonder whether studies have been made to clarify the influence that heart rate has on organs' functionality (apart of the rate of circulation).
In other words: If we replace "blood" circulation mechanism by another mechanism that could provide a stable circulation flow, would it have any major influence in vital organs' functionality?
Perhaps you will find some answers in the lvad publications.
10.1159/000491872
10.1111/j.1540-8191.2010.01075.x.
As the researchers explained, the heart is not just a muscle pump but also a large endocrine gland. The heart contains important hormonal secretions that affect almost all functions and physiology of the body. Cardiac hormones and peptides play a very important role in regulating electrolytes - body fluids and the secretion of other hormones
Is it possible to remove the heart tissue and replace it by mechanical means? I think this will cause a multiple organ failure. Is there any experiment related to this?
Patients fitted with total artificial hearts have their hearts explanted and completely replaced by mechanical contraptions that perfuse the body. This was usually undertaken as a "bridge" to keep patients alive and in relative good condition while waiting for an allogenic heart transplant.
Medical practice has currently migrated away from "total" heart replacements and towards pumps that are fitted inside the heart and take over the task of pushing blood. Interestingly, these pumps work continuously and thus the patient has no pulse! Despite this, these pumps really improve patient status dramatically!
Pushing blood without a pulse does appear to have some unforeseen drawbacks; carotid baroreceptor rely on pulses to monitor arterial pressure and thus "read" lower pressures, unnecessarily stimulating the sympathetic nervous system. The lack of pulse could also lead to more gastrointestinal bleeding in these patients, through hitherto unforeseen mechanisms.
As for total cardiac explantation and fitment of artificial hearts, Lotfali Bolboli is indeed correct. Heart produces several hormones, like BNP. BNP levels rapidly drop to almost zero after explantation and BNP supplementation is necessary to protect patients from rapid renal failure (10.1016/j.jtcvs.2003.07.023).
All in all, there's nothing to indicate that there exist insurmountable obstacles to replacing the heart with something else that provides "stable circulation flow", but the challenges are great and have currently led medical science to gravitate towards devices that help patients' biological hearts!
I hope that helped.
The pulse isn't just about bulk delivery,, That rhythmic pounding creates shear forces vital for healthy blood vessels, triggering beneficial signals (like nitric oxide release). It also helps flush waste via lymphatics and seems important for fine-tuning function in organs like the kidneys and brain. Stick a patient on a totally non-pulsatile pump (like some heart assist devices), and you start seeing problems bleeding, valve issues – highlighting the pulse's hidden jobs.( i had these Sources: JACC Heart Failure 2023 meta-analysis (LVADs), PNAS 2023 (lymphatics/glymphatics), Guyton & Hall Physiology 15th Ed)*
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