Q&A: What is an artificial heart assist?

Q: What is an artificial heart?

The implantable artificial heart assist device introduced in this article is suitable for patients with severe heart failure whose heart (left ventricle) pumping function is weakened due to myocardial infarction and cardiomyopathy. The artificial heart assist device is suitable for patients who have difficulty maintaining blood circulation after drug treatment and whose diseases cannot be cured except for heart transplantation. Since it is implanted in the state of preserving the patient's heart, its function is to assist the work of the left ventricle while the patient is waiting for a heart transplant, so it is also called a "left ventricular assist heart" (see the figure below). In the classification of Japan's Pharmaceutical Affairs Law, it is classified as a "highly managed medical device" with the highest risk to the human body. The artificial heart assist device has been selected as a research object at the "Symposium on Accelerating the Introduction of High-Demand Medical Devices" held by the Ministry of Health, Labor and Welfare of Japan, and people have been looking forward to its early practical application.

Assists the function of the artificial heart
Assists the left ventricle in pumping blood to various organs.

Q: How to use an assisted artificial heart?

The implantable artificial heart is generally composed of two elements. They are the "blood pump" that assists the left ventricle and the "controller" that drives the blood pump. The blood pump can be implanted in the body, while the controller is used outside the body (see the figure below). The size and weight of the controller are moderate, and the patient can carry it on his shoulder. The controller of the artificial heart of Sunmedical Technology Research Institute weighs about 4.3kg, and the controller of Terumo weighs about 2kg. The feature is that when patients use the artificial heart, they can be discharged from the hospital for recuperation at home, and can also carry it with them when walking in daily life. The artificial hearts of Sunmedical and Terumo were both included in the insurance catalog in February 2011, and the price (price of medicine and medical equipment) after using health insurance is 18.1 million yen.

The main components of EVAHEART
include the implanted part (blue text) and the external use part. (This picture was drawn by Nikkei Electronics based on Sunmedical's data)

Q: What development trends have been reported previously?

Looking at the history of artificial heart assist, the world's first clinical application can be traced back to the United States in 1968. At that time, all products were external, and patients had to be hospitalized when using them. Subsequently, the development of implantable blood pumps continued to progress, and pulsatile blood pumps came out in the 1980s. Artificial hearts assist can pump blood through "thump thump" beating like a real heart. However, there are problems such as large size, which requires the patient's body shape, and it is easy to be damaged. Therefore, the development of a next-generation product is a continuous flow blood pump that transports blood through the rotation of the impeller. Both Sunmedical and Terumo's artificial hearts assist use continuous flow blood pumps, but the way they drive the impeller to rotate is very different.