A 25-year-old boy has no heart for 555 days： artificial heart maintains life to change heart.

　　In the past 18 months, few people have noticed that Stan Larkin is a man without a heart.

　　This 25-year-old black guy has a thick body, likes to hang out with his younger brother and always takes his three young children to the park to play. He looks like a normal man.

　　The only special thing is that he always carries a gray backpack and never leaves his body for 24 hours. Go out, carry your bag on your back, even if you sit down for a haircut, put it at your feet.

　　Two pipes came out from the corner of the backpack, penetrated into Larkin’s clothes, buried under his ribs and connected to his "heart". As early as 2014, Larkin’s heart was removed and replaced by a Total Artificial Heart made by Syncardia Systems, Inc The backpack is filled with a portable driving device that provides power for it.

　　To put it simply, this backpack and all-artificial heart system maintain Larkin’s life.

　　It was not until May 9th that he transplanted a donor’s heart at the frankl Cardiovascular Center of the University of Michigan that he finally unloaded the backpack.

　　Cynthia’s total artificial heart handed out the baton, successfully ending its 555-day term.　　

　　"Many people may be afraid of using artificial hearts, and what I want to tell you is that you need to overcome this fear because it will help you." Before leaving the hospital, Larkin described this journey as a "roller coaster" when sharing his experiences with the public at a media meeting. He feels that he can recover quickly after surgery, thanks to the escort of the total artificial heart while waiting for the transplant.

　　"I feel like I can jog now." The man who just changed his heart two weeks ago said with a smile.

　　A machine will become my heart, think about it, a machine.

　　Larkin never thought that a man could live without a heart, let alone this happened to himself.

　　He hesitated for half a month before agreeing to the doctor’s treatment plan to install a total artificial heart for him. "A machine is going to be my heart," he said with an incredible expression. "Think about it, a machine!"

　　But he had to accept the machine. At the age of 16, Larkin went into shock on the basketball court without warning. Soon, he was diagnosed with arrhythmogenic right ventricular cardiomyopathy.

　　In human body, the heart promotes blood circulation throughout the body through the relaxation and contraction of atrium and ventricle. Larkin’s disease will make the myocardium of the right ventricle be replaced by progressive fibrous adipose tissue, which will cause the right ventricle to expand and not contract normally, which will lead to arrhythmia and even sudden death.

　　"The best choice for him is to receive a heart transplant." Jonathan Gaft, Larkin’s attending doctor and frankl Cardiovascular Center of the University of Michigan, said, "But at the same time, we feel that his condition is changing very fast, and he may not wait for the day when his matching donor heart arrives."

　　According to Billy Coen, director of the Technology and Innovation Center of Texas Heart Association, some patients with advanced heart failure often have to wait for months or even years to get a suitable heart source. Because the heart is too weak, key organs including kidneys and liver are likely to fail in the process. Without some forms of support such as artificial heart, many patients will die while waiting. According to the data provided by the American Organ Acquisition and Transplantation Network (OPTN), 49% of people on the waiting list for heart transplantation have to wait for one year or more.

　　Larkin’s situation is getting worse. After developing from right ventricular dysplasia to total heart failure with bilateral ventricular involvement, his left and right ventricles could not effectively collect and pump blood. He was so weak that he could hardly get into the car by himself.

　　Prior to this, the doctor implanted an automatic cardioverter defibrillator for him. When necessary, it will send electrical pulses to "activate" the regular operation of the heart. However, after the illness worsened, this commonly used cardiac auxiliary equipment was not enough to maintain Larkin’s life.

　　In November 2014, after a series of physiological tests, the doctor decided to remove Larkin’s heart and implant a Cynthia artificial heart to replace the original left and right ventricles and four valves.

　　This new "heart" is a pneumatic bicentric pump. After connecting with Larkin’s atrium, aorta and pulmonary artery, it began to perform its duties. As a mechanical heart, it can pump 9.5 liters of oxygenated blood per minute, which is beyond the ability of ordinary healthy heart and close to the level of athletes.

　　There is no sensor or engine in Larkin’s body. Through two pipes, the electric external driver transmits oxygen and creates vacuum, controls the synthetic material membrane separating air and blood in the ventricle of the total artificial heart, and pumps blood to the whole body.

　　"Tick-tock … … Tick-tock … …” This machine has accompanied his life all day. With each accurately calibrated compressed oxygen pulse, the driving equipment in the backpack makes a strong, stable and rhythmic sound, which sounds like a fast horse galloping through the hard road.

　　A few weeks later, Larkin, who was used to the noise, finally fell asleep with it. "It kept me alive," he said. "That’s it ‘ The sound of heartbeat ’ 。”

　　Larkin is challenging the limits of this equipment.

　　Two days before Christmas in 2014, Larkin walked out of the hospital with his family and became the first person in Michigan to leave the hospital with a total artificial heart.

　　"Although there is a backpack connected to my body, it’s like a real heart," Larkin joked. "It feels like I’m going to school with a backpack full of books on my back."

　　Like every ordinary person celebrating Christmas, he went shopping in the shopping center, went to church to participate in activities, and accomplished something he had been longing for for for a long time — — Picked up the basketball with the device that kept him alive.

　　Gaft, the attending physician, took a deep breath when he saw the pictures of him dribbling.

　　"This artificial heart is not designed for playing street basketball," Gaft said. "Larkin is really challenging the limits of this equipment."　

　　Hu Shengshou, academician of China Academy of Engineering and president of Fuwai Hospital, introduced in an article that artificial heart broadly includes ventricular assist devices and total artificial heart, in which ventricular assist devices are mainly left ventricular assist devices.　

　　It has been 80 years since the Soviet scientist De Mihov transplanted the artificial heart into dogs in 1937. In 1969, American doctor Cooley completed the first successful total artificial heart transplant in Texas Institute of Medicine, and assisted the patient with a total artificial heart for 64 hours before the heart transplant.

　　In China, the related blood pumps being developed by Tianjin TEDA Cardiovascular Hospital, Beijing anzhen hospital and Suzhou University are still in the animal experimental stage. There is no breakthrough report on the development of total artificial heart in China.

　　Cynthia total artificial heart is recognized as the most successful of more than 10 kinds of total artificial heart devices that have been published so far. Ten years ago, it was approved by the US Food and Drug Administration (FDA) as an auxiliary treatment before heart transplantation. It is also the only total artificial heart certified by the United States, Canada and Europe for clinical application.

　　Although Larkin, who came home with Cynthia’s artificial heart, can’t move completely freely, for example, the electric drive device connected to him prevents him from standing under the shower, picking up children or carrying them around his neck as usual, all this is very rare.

　　When the total artificial heart was just implanted, two pipes drilled from Larkin’s left rib were connected to a driving device called "Blue Giant".

　　It weighs 188 kilograms and looks like a washing machine. This means that Larkin can only be tethered to the hospital by this cumbersome machine until it takes the doctor months or even years to find a matching heart donor for him.

　　Fortunately, in June of that year, this small and portable all-artificial heart drive device newly developed by Syncadia Systems was approved by the US Food and Drug Administration. Larkin’s "washing machine" was replaced by a "backpack", so he no longer had to be trapped in the hospital.　

　　"When eligible patients become stable, they can switch to portable drives," the production company said. "It provides patients with a wider range of activities and allows them to return to their families and communities to wait for a matching donor heart." It is powered by two lithium-ion batteries and can be recharged with a standard power socket or an adapter of a car.

　　This equipment, weighing about 6 kilograms, was named "Freedom".

　　In order to permanently replace the human heart, it has to overcome many technical difficulties.

　　It seems that Larkin is doing well with a total artificial heart. At home, he doesn’t need more treatment, as long as he eats a low-sodium diet and takes blood-thinning drugs to keep healthy. Of course, as a person with a total artificial heart, he has to be like a robot and can’t leave the power supply for too long — — The lithium battery in the equipment is enough to run for 3 hours.

　　However, total artificial heart is only used as an alternative transitional treatment before heart transplantation, and it can not be maintained for a long time. Cynthia’s total artificial heart, which is at the forefront of the industry, is also starting the clinical trial of permanent artificial heart transplantation.

　　Academician Hu Shengshou introduced that although heart transplantation is the best treatment for many patients with end-stage heart failure who can’t be treated by drugs or surgery, it is still the goal pursued by the medical community for many years to use artificial heart instead of natural heart because of the limitation of heart source and the fact that heart transplantation is not suitable for patients under 40 years old.

　　Although the current research is more and more advanced, in order to permanently replace the human heart, the total artificial heart has to overcome many technical difficulties. For example, as an artificial mechanical device, it does not have the self-repairing function of human heart, and it is impossible to stably simulate the heart beating more than 100,000 times a day for a long time without wear.

　　"Larkin is still waiting for a heart transplant, and we hope to transplant him as soon as there is a suitable donor. During this period, he can return to health in some normal life at home, and when the opportunity comes, he will be transplanted in the best condition. " Dr Jonathan Gaft said.

　　In order to serve the heart of this substitute, Larkin’s family took over most of the work of the nurse. The mother, who was afraid of touching two pipes at first, was used to often changing the bandage covering the entrance of the pipe for her son.

　　"We have to be careful so that he won’t get infected," she said. "Now, I’m a professional."

　　After 555 days of being accompanied by Cynthia’s total artificial heart and "freedom" drive equipment, Larkin finally got a heart from a donor.

　　Now, in his chest, a fresh human heart is beating steadily.

　　This is the third heart he experienced, which made him feel "reborn". "You can stop worrying about small things and do many things that you once thought you could never do again."

　　Including hugging his three children again.

　　"They will attack me," the father showed a spoiled smile. "They can’t wait for a long time. They will hang in front of my neck, jump on my back and ride on my neck. In short, they will run around me. " China Youth Daily Zhongqing Online Reporter Chen Yinan