Real Heart´s solution to a total artificial heart (TAH)
The heart consists of two atriums and two chambers. The right side is a low-pressure system and the left a high pressure system. The non-oxygenated blood from the body flows into the right atrium, then goes through the right chember into the pulmonary circulation, is oxygenated and will return to the left atrium and then be pumped through the left chamber into the body again. Between the atria and chambers are valves preventing the blood from going backwards during pumping.
It has traditionally been considered the heart is a kind of “squeeze pump” where the muscle of the chambers squeezes blood out into the body. Swedish research, however, has in recent years shown that the heart is not squeeze-pumping, but is functionally a piston pump. Between the atrium and chember is the so-called AV-plane. AV plane is short for atrioventricular plane. In this plane, there are valves both on the left and right side.
Pump movement is a rapid downward movement of the entire AV-plane. The movement is almost like a pistol shot. Very fast and with quick pressure increase. When the AV-plane moves downwards the valves close and the volume of blood in the chamber is bouncing off the bottom of the chamber and into the respective arteries on both sides. This is the principle of operation which gives rise to the pulse in the bloodstream.
The pulse is important to maintain the function of many organs. It has also been shown that the heart rate is important to prevent the major blood vessels from solidifying.
Another important effect of this principle pumping motion is that as the valves closed during the downward movement created the negative pressure in the atrium. This negative pressure is important for the blood to be drawn into the atrium and refill the atrium with a new portion of the blood to be pumped out to the lungs and aorta during the next pumping movement.
Scandinavian Real Hearts total artificial heart (TAH) is created so that it is an almost exact copy of both the principal normal pumping motion, normal pressure and that it can give rise to normal pulse. Refilling of the atriums is also done in a normal way.
Another important factor is most likely chamber design. There is much to suggest that the chamber design is of importance to get the right acceleration of blood into the arteries during each pumping motion. This together with the design of the chamber’s interior surface (trabeculation) is most likely important to prevent clot formation. These factors will be further scientifically studied by the company.