On January 13, the news that the first patient with artificial heart implantation in Shandong Province was successfully discharged from the hospital in Qingdao quickly appeared on the hot search, and just a few days ago, the first 57-year-old man in the United States to transplant a pig heart was exposed by the media as "no abnormal reaction in 3 days"! So the question is, which is better for patients to implant pig hearts or use artificial hearts? Which approach is more promising?
The artificial heart does not completely replace the patient's own heart, it is a cardiac assistance system to be exact. The artificial heart is composed of two parts, in vivo and outside the body, the internal part mainly includes artificial blood vessels and blood pumps, through the blood pump to suck out the blood of the patient's ventricle, and then through the aorta to all parts of the human body to achieve blood circulation. The blood pump is placed under the heart and weighs about 0.4 kg.
The outer part of the body is a box-like controller, weighing about 6 pounds, which can be carried in a backpack for walking. A wire runs through the navel to connect the artificial heart pump to the controller and is equipped with multiple removable batteries to power the heart pump.
The 57-year-old man in the United States is the world's first successful transplant of pig heart in a normal patient, because in 2020 a pig heart was transplanted into a brain-dead woman. Different from transplanting human hearts, pig hearts belong to "xenotransplantation" and need to solve two tricky problems: one is the immune rejection between pigs and humans; the other is that pig hearts may carry bacteria and toxins that cause human diseases. This is also the reason why "xenotransplantation" has not been promoted for many years, and it has not been until the rise of genetic engineering in recent years that progress has been made.
So from the technical difficulty of speaking, pig heart transplantation is far larger than the artificial heart, to know that as early as the 1940s artificial heart was developed by the American doctor John Gibbon, and then by the mayo medical center doctors improved, the birth of the famous "Mayo artificial heart and lung machine". Subsequently, the artificial heart continued to improve, the size became smaller and smaller, the function became more and more complete, and some people have used the artificial heart for 11 years in the world.
In contrast, pig heart transplantation is still in its infancy, and the United States is in the leading stage. However, China is also in the first echelon in terms of organ transplantation. For example, the Pig Heart of american men has modified a total of 10 genes, namely 3 genes that cause human rejection, a gene that promotes the rapid growth of pig hearts, and 6 genes that make it easier for the human body to accept pig hearts, and behind these work there is the figure of Yang Luhan, a Chinese Sichuan girl.
It turned out that After graduating from Peking University, Yang Luhan went to Harvard University in the United States to pursue a doctorate, and the supervisor was the famous Church. Church is not simple, he is an authority in the field of biology, but also a professor at the Massachusetts Institute of Technology and Harvard University.
In 2014, Yang Luhan led a 10-person study piglet to knock out the disease-causing gene in the pig using CRISPR-Cas 9, a gene cutting technology. In 2017, the world's first non-toxic "pig 1.0" implantable in humans was bred. Yang Luhan cleared the way for pig heart transplantation, so some people in the industry predicted that the realization of "human implantation of pig heart" would not exceed 5 years.
With this achievement, Yang Luhan was named "30 Under 30 Under 30 in Science and Medical Field" by Forbes in 2014. Now Yang Luhan has returned to China to become a scientific research center and has developed "non-toxic" pigs to 3.0.
And then there's the practicality. In 2001, New England published a survey article stating that people with heart disease were randomly divided into two groups, one taking medication and one using an artificial heart. After a period of time, it was found that drug treatment was inferior to artificial heart in terms of survival rate, efficacy and controllability. The prospects for an artificial heart are undoubtedly enormous.
What kind of effect the transplanted pig heart plays on the patient needs to be further observed, and further adjustment may be made in the process. However, once successful, patients do not need to carry additional equipment, and life is more convenient. In addition, pig heart is only a small application of "xenotransplantation", and it is possible to extend more uses after the technology matures, such as retinal transplantation, liver transplantation, kidney transplantation, etc. There are opportunities to try.
Cost is also one of the factors that hinder the large-scale rollout of a technology. The cost of installing a labor is about 300,000-500,000 yuan, due to the existence of immune rejection in the artificial heart and the human body, it needs to be maintained with drugs every year, which costs about 100,000 yuan per year. Objectively speaking, this cost is still relatively high in China, and it is mainly used by patients with economic conditions. However, as technology evolves, costs will continue to fall.
How much it cost american patients to transplant pig hearts, the media did not report, but it is undoubtedly an astronomical number. Some experts said that after the technology matures, a genetically modified pig heart can be produced every few months, and the price will drop sharply. However, experts also said that the price of pig hearts is likely to remain high for a long time, which is not acceptable to ordinary people.
Which is better, artificial heart or pig heart? From the current stage, artificial heart is feasible, but from the perspective of future prospects, replacing "pig heart" is more promising. Our country has a large population and a large difference in income, and from any point of view, both routes need to be taken, not one of them.
Original: Blog post