Very interesting question. Unfortunately for us to have two working hearts, we will need to have double of everything which includes: Two hearts, four lungs (2 x 2 lungs) and double all our blood vessels. I have never heard of a case where a baby is born with two hearts (unless you’re looking at joined twins). The heart and the cardiovascular system is very big, it contains a lot of vessels and connects to the lungs and to all your organs. So to have 2 hearts that has all these connections is impossible.
One of the first things to develop in a baby while it is in the mother, is its own heart. That is why when a mother goes for their first scan the doctor listens to the baby’s heart to make sure it is okay. At that stage if the baby had 2 hearts one of them would have to be working for it to be alive otherwise it would die. The other most likely will just be a lump of tissue that could be removed if the baby is born.
But what we are doing in hospitals now, is for people with poor hearts, we are able to give them a transplant of a plastic heart which can help beat for them. This works along with their own heart and so in a way they have 2 hearts beating for them. This allows them to survive – so in this case, having a second heart is very important for them to be able to live.
If we were able to have plastic hearts as well as our own this will greatly improve our life. Firstly our heart will not have to work as hard so it will survive for longer and be healthier for a longer time. Also all our body will get more blood and oxygen quicker and more often, so our organs will be healthier as well. But we have not yet designed something which will work with healthy heart, only transplants for hearts that are poorly. It is a very complicated thing to design and get to work so i’m sure it’ll be many more years before someone tries something like this.
Our hearts are incredible organs, and they generally work brilliantly.
There are very few occasions where a secondary heart would really be needed (like Fiona, I’m not personally aware of a case of an individual possessing two hearts). It’s only in very intense physical activity that a hearts capacity can be truly reached (most people never ‘push’ it that far). However, a hearts function may be limited if it is diseased (so look after it!).
I never knew people were even trying to implant a second heart.
If you could theoretically graft a second heart onto the same aorta (tube that leaves your heart for the rest of the body) could this improve exercise performance? Well, considering the classical model of exercise performance, I think it just might. if you had two hearts then you could pump twice as much blood to the muscles during high intensity exercise when they need it. More blood, more oxygen, longer exercise performance. I think this must be classified as cheating though???