The heart is basically a fairly simple organ. Four chambers, some valves and cleverly interconnected piping – so the physical pump is ready.

But if our pump is no longer working properly, the situation is bad. In people with severe heart failure, the pump is so weak that it can’t move blood around the body efficiently – causing the person to pant a lot, even at rest, and the organs, which don’t have an adequate supply of blood, don’t they take in neither oxygen nor nutrients. Many times the only solution is a new heart.

However, heart donors are few and far between. In Germany this is mainly due to the fact that organ donation can only be done with explicit consent. That is why it is necessary to find alternative solutions to deal with heart problems.

Decades of research

For more than 60 years, cardiologists and heart surgeons have been discussing the dream of the artificial heart. For a weak heart, not yet completely damaged, there are systems that can support parts of it. But for patients, both of whose heart chambers are in bad shape, this is not enough: the entire heart must be replaced.

The development of such models has also been researched for decades. In 1982 it was held in the USA. the first permanent and complete heart implantation. However, these hearts are mostly rudimentary – without being adapted to the needs of each patient.

When the first artificial heart was implanted a decade ago, which was actually adapted to the patient, it caused a great sensation. French heart surgeon Alain Carpentier, who led the operation, had already become known for his research and work on heart valves, having replaced artificial materials with biological surfaces. The latter have the great advantage that after the operation the patient does not need to take anticoagulant drugs for the rest of his life – a medication that seriously increases the risk of bleeding.

Carpentier used such material in the rest of the heart as well, creating an artificial heart that adapts to the patient’s physical activity. Because anyone who does not want to be lying down all the time, but also sits, walks, runs and dances, needs a heart that works properly in these activities as well.

The first implantation of the so-called Carmat heart was done in a 76-year-old man with severe heart failure, who lived 74 days after the operation. In the past years, many adjustments have been made to the material of the surfaces, the operation and the pumps, as Stefan Pia, head of the Carmat company explains, while 50 more artificial hearts have been implanted. The 14 patients lived with an artificial heart until a donor was found. In 15 other cases the patients are still living with the artificial heart – the remaining patients have died.

Carmat heart problems

However, the Carmat heart presents some problems. For example, it’s too big – so it’s not suitable for all busts, and for many women.

In addition, the heart is very complex: it consists of 250 parts, “every one of which can break,” says Evgeny Potapov, head of the program for mechanical circulatory support at the German Cardiology Center of the Charité. That is why it can present more malfunctions than simpler artificial hearts. Also, as in all things, the advantages it offers come at a high cost – each heart costs around 200,000 euros.

According to the company’s data, after six months about half of the transplanted patients are no longer alive, Potapov points out – a high percentage. Of course this is not solely due to the Carmat heart, but also to the fact that the patients are usually seriously ill.

Finally, there are more people on the waiting list than there are heart donors. For less serious heart problems, however, simpler support systems can be preferred, which provide a solution for some years – while the search for an organ donation continues.

So far it is not a permanent solution

Could anyone live long with a Carmat heart? Although this does not seem particularly feasible at the moment, Pia emphasizes that the company aims to offer a long-term solution within the next year. Until now the Carmat heart is available on the European market only as an intermediate solution. “If it was half the size and had no technical issues, then I would support the product immediately,” says Potapov. However, at the end of 2021 the company removed the product from the market for a whole year due to major quality issues.

In the meantime, experiments are being carried out with the implantation of genetically modified hearts from pigs or with the reconstruction of heart tissues through tissue engineering. In the coming years it will be seen which technology will be the biggest innovation. As well as whether the willingness to donate organs will at least to some extent limit the problem.