Let’s imagine that organs can be perfectly grown in a lab and installed into a body without any chance of rejection or other complications usually associated with organ transplant.
You, a perfectly healthy adult human, go to the doctor and have them put a second heart in your chest that is connected to the circulatory system with your original heart.
What would be the effects of this? Could it even be done in this hypothetical situation at all?
If they’re in series the pressure will increase, if they’re in parallel the flow would increase. Just have a pacemaker organ connected to both to time the pumps. You could reduce blood pressure but increase the amount of blood flowing, therefore less wear and tear on the hearts, arteries, organs, etc.