Did you know that "cyborgs" don't just appear in science fiction books, they also exist in the real world?
Peter Houghton is an Englishman. In the last years of his life, he had no pulse, no heartbeat, and no blood pressure. If you connect him to a heart monitor, a straight line will always appear on the device.
But he is not dead, he lives. In his heart, there is an electronic pump the size of a thumb that drains the blood from his left ventricle around the clock and sends it into the aorta, and so on.
The electronic pump was connected to a wire that protruded from his skull behind his ear and connected to a controller with a battery—the controller of his life.
Peter relied on this electronic pump and lived a normal life for seven and a half years. Until 2007, at the age of 69, he died of multiple organ failure, and doctors pronounced him dead by removing the battery from the electronic pump.
Peter is currently the longest-living person with an artificial heart. And his example, to some extent, proves that it is possible for human beings to live entirely on artificial hearts.
An artificial heart that does not beat.
The electronic pump used by Peter, called the "Javik 2000", was invented by American scientist Robert Javik in the 90s of the last century.
In those days, artificial hearts were basically used as a transition before heart transplantation**. This is because patients with severe heart failure need to be fitted with a ventricular assist device to replace the patient's tired, barely moving heart before they can find a suitable donor heart.
At that time, ventricular assist devices were pulsatil, meaning that artificial devices would mimic the way the heart beats and carry blood throughout the body.
However, some scientists have found that blood vessels and organs do not feel the heart's pulse at all, and that it is important that the blood circulates in the body, not beats.
Through animal experiments, they proved it. This concept completely turns the way artificial hearts are designed.
It was against this backdrop that Javik 2000 was born. It is battery-powered, small, non-pulsating, and works very quietly with minimal noise and vibration. It will be installed in the patient's left ventricle with an impeller inside the pump to 1 1 per minuteAt 20,000 revolutions, it pumps 5 liters of blood per minute, similar to a normal heart.
This heart pump is not limited to transition**, the designers believe that it has the potential to replace a heart transplant as a permanent**.
In the UK, patients applying for donor hearts are subject to rigorous vetting, and the heart will be transplanted to younger patients with milder symptoms, while older patients with more severe symptoms are almost impossible to pass the vetting process, which is equivalent to a death sentence.
Peter Houghton is undoubtedly the latter. Prior to the surgery, the 61-year-old was diagnosed with dilated cardiomyopathy, which is only 10% normal in heart function, has difficulty breathing with the slightest exertion, and can make him sweat profusely just by talking. He could not walk, could not lie flat, and could only sleep with a pillow cushion and sit.
Doctors believe that Peter has only a few weeks left to live. So, when Peter learns that such a heart pump exists, he volunteers to be the experimenter of "Javik 2000", "I'm just going to trade a definite slow death for an uncertain choice." ”
People who have lost their heartbeat.
In June 2000, Peter underwent surgery to implant a heart pump.
The doctor opened his ribcage, slit open his pericardium, revealing the barely moving heart, and then dug out a piece of heart muscle at the tip of the heart and pumped it into his swollen left ventricle.
The wire connected to the heart pump passed through his neck and reached the back of his left ear. There, the doctor drilled a screw hole in the skull with an electric drill and attached a miniature three-pin socket that connected to an external battery and controller.
In the past, wires usually protruded from the stomach, but because the fat layer of the stomach is thick, there is a high probability of infection. The scalp has almost no fat and the socket is firmly attached to the skull, so this time the doctor let the wires stick out of the skull.
After the surgery was completed, Peter became a "cyborg" who lived entirely on batteries. On the 11th day after surgery, Peter was discharged from the hospital. Two weeks after surgery, he was able to walk three kilometers.
Slowly, Peter was able to live like a normal person. He has participated in many fundraisers for heart charity**, he has even climbed mountains, flown around the world to give lectures, and once he participated in a charity march that covered 144 kilometers.
However, he could not leave the battery for a moment. The battery needs to be replaced twice a day, and the body needs to be connected to the power source when you go to bed at night. Also go out with a backpack with his controller and batteries.
The doctor joked that he was like "Frankenstein."
One winter, when he was out shopping, he suddenly felt a sharp pain in his head. It turned out that a thief had snatched his backpack - the thief thought it contained a camera. As soon as the wire was disconnected, the alarm in the bag made a screeching sound, and the thief was so frightened that he threw the bag down and ran away.
The kind passer-by picked up the bag and gave it back to Peter, who fumbled for the wires, but fortunately the power was not long and did not cause serious consequences.
What is it like to live with a heart pump and completely lose your heartbeat? Peter said he felt as if he had really become a cold-blooded, heartless man. "I've become less emotional, and yes, very noticeably less emotional. ”
Doctors have different opinions about the changes in his mood. Some doctors believe that the heart is indeed associated with emotions. For example, when a person is angry or scared, his heart rate is disordered, and the chaotic heart rate activates the part of the brain that controls stimulation and excitement; Conversely, when a person's heart rate is stable, the brain produces substances that make you feel calm and relaxed.
Peter's heart was no longer beating, which most likely affected his mood. On the other hand, there are also doctors who believe that Peter only suffers from clinical depression, and his mood swings are not too big because he is pessimistic about his life prospects.
In November 2007, after seven and a half years on batteries, Peter passed away. The doctor re-removed the heart pump in his body, and it was still like new, with very little wear and tear on the bearings inside.
And the mystery of Peter's emotions is unsolvable. After all, Peter had set foot in a no-man's land, and no one had ever survived with an artificial heart for so long as he did.
Hope for tens of thousands of heart failure patients.
In fact, the history of artificial hearts is very short.
It was only in 1969 that the first artificial heart implant was performed. At the Texas Heart Transplant Center in the United States, a 47-year-old man is implanted with a ventricular assist device as a pre-transplant transition**. The artificial heart was only in the patient's body for 64 hours before it was replaced with a donor heart, but the patient died of an infection shortly after surgery.
The first time an artificial heart was made permanent** was in 1982. The patient, Barney Clark, was 61 years old at the time and, like Peter, had no hope of waiting for a donor heart. His implanted artificial heart was "Javik 7", and he lived for 112 days with this electronic heart.
To this day, heart transplantation remains the main predominant cause of patients with severe heart failure.
There are just over 5,000 heart transplants performed worldwide each year, and tens or even hundreds of thousands of patients are eagerly waiting for a suitable donor heart. Every year, a large number of patients die while waiting.
Especially for patients with end-stage heart failure, an artificial heart is almost their only hope.
In 2019, half of all patients had to wait more than a year for a heart transplant. **the conversation
At the same time, the technology of artificial hearts is constantly evolving.
The earlier "Javik 7" was later improved and renamed "Syncardia Tah", a fully artificial heart that assists both the left and right ventricles.
In the past, patients who had an artificial heart implanted had to lie in the hospital all the time in order to wait for the transplant. With the implantation of "Syncardia Tah", the patient can live a normal life until a donor heart is found.
Stan Lakin, a 25-year-old boy in the United States, who has a rare cardiomyopathy, had this artificial heart implanted. According to a 2016 report, he lived a healthy life for 555 days after surgery. But no new reports about him were found.
In 2015, Javik Heart launched the heart pump "Javik 15mm". It has a diameter of only 15 mm and is specially designed for pediatric heart failure patients aged 1 to 10 years. However, the cost of the artificial heart is extremely expensive, and the cost of the device alone is as high as 190,220,000 US dollars (about 1,351.56 million yuan), not including the cost of surgery.
In China, the research and development of artificial hearts is also constantly advancing.
Three domestic artificial hearts, including Evaheart, CH-VAD and Heartcon, have been approved for marketing. Dr. Gong Ming of the Cardiac Surgery Center of Beijing Anzhen Hospital believes that these domestic artificial hearts have reached the international leading level.
In July 2022, the first artificial heart implant operation in China was also performed at Beijing Anzhen Hospital. The patient is Mr. Zhang, 47, from Inner Mongolia Autonomous Region, who suffers from severe dilated cardiomyopathy. One month after the operation, Mr. Zhang was discharged from the hospital with a black crossbody bag containing an extracorporeal controller for an artificial heart.
In the future, artificial hearts will become more and more important.
You can imagine that after the technology of artificial heart matures, heart failure patients no longer need to wait for a kind stranger to donate their heart, but directly resort to technology, implant a miniature artificial heart, which can extend life expectancy and improve the quality of life.
References[1]Stephen Westaby. Open a Heart, Guangxi Normal University Press. [2]khan, sanna, and waqas jehangir. 2014. "evolution of artificial hearts: an overview and history".[3] World Heart Day |Can an "artificial heart" bring a patient back to life? The Paper [4]."longest-living recipient of artificial heart worldwide". 2007. los angeles times.[5]"obituary: peter houghton". 2007. the guardian.[6]"heartfelt: man says metal heart left him cold". abc news.[7]longest-living recipient of an artificial heart dies. the washington post.
*丨Bring Science Home (ID: steamforkids), Popular Science China.