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?
As others have pointed out the issues, I will answer a different question.
It would be cool to have a backup heart. It sits unused and quite until needed. Clearly some issues with experiencing the same conditions as the first heart. If it were biological, then it would weaken without use.
But a small pump to survive a heart attack would be nice.
NAD.
Having said that, if your “primary” heart is having issues it’s usually something that a second heart wouldn’t be able to bypass.
For example, if the heart chambers are just fluttering then your second heart could try to take over, but I imagine that if the primary failing one would cause so much ruckus that the secondary wouldn’t be able to keep up normal blood flow.
I imagine a better system with some electronics that can either work as a pacemaker or take over completely in an emergency situation by just plain stopping the heart and taking over until help arrives, or something like that.
Again, NAD