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2020/04/12 06:54:33

Heart of the person

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Content

Main article: Body of the person

As heart is arranged

Heart of the person - four-chamber. It is separated by a continuous partition into two parts – right and left (in the right half of heart blue blood, in left — arterial flows). The right and left half of heart are separated by an incomplete partition into two reported departments: upper department – auricles (the right and left auricles) and the lower department – ventricles (the right and left ventricles).

Openings between auricles and ventricles are closed by folding valves which are attached by tendinous threads to heart walls. Between the left auricle and the left ventricle there is a two-fold (mitralny) valve, between the right auricle and the right ventricle the three-leaved valve is located.

The mass of heart fluctuates within 200 — 400 g on volume heart comparably with a fist (750 cm3).

Intracardial nervous system: as heart is controlled

Main article: Intracardial nervous system

Though heart first of all is controlled by a brain and the autonomic nervous system, it also has own mini-"brain" called by intracardial nervous system. It controls external vegetative signals and supports a full-fledged work of heart in any situations. Read more here.

3D model of "brain" of heart created by researchers from Thomas Jefferson University

Own electrical system

The human heart taken from a thorax is actually capable to fight during the short time frame as it has an own electrical system and will continue to receive necessary elements from an ambient air.

Heartbeat

Heart of the average person fights with frequency of 72 blows in a minute. Thus, in 65 years of life heart is capable to be reduced by 2.5 billion times.

For comparison we will notice that heart of a mouse fights with frequency of 500 beats per minute, and at an elephant this value — only 25 beats per minute.

In work of heart there are moments of a respite – then it "is silent" between reductions. For lifetime heart "has a rest" about two decades.

One video below we observe through MRT work of heart which at us, as well as at other mammals, four-chamber.

Two cameras which on video are located at the left below are the auricles collecting blood from all body (the right auricle) and from lungs (the left auricle). Having saved up the come blood, auricles are reduced, at the same time valves open, and blood comes to two other cameras — ventricles, they are visible more to the right above. Then there comes the phase of reduction of ventricles. The closed valves do not pass blood back in auricles, and it streams in an artery — the vessels departing from heart (they in this foreshortening are not visible).

After that there occurs complete relaxation of heart, it "has a rest". Valves in the basis of arteries do not allow blood to go back. But rest is short — it is necessary to turn to work again and to perform the next reduction. Looking at this video, the doctor can tell whether the patient of congenital defects or other diseases of heart has no he.

Pumping from 6 to 30 liters of blood a minute

Heart is the powerful pump which is pumping over blood through arteries and veins. The blood volume which is pumped over by heart in one minute is 6 l (with a speed of blood-groove of 2 km/h, i.e. the way of blood by hand to language takes 15 seconds, from one brush to another — 13 seconds and from a hip to foot — 2 seconds), but can reach also 30 l/min if heart is overflowed with blood, for example, when the person is in a status of excitation or executes heavy physical activity.

At rest heart pumps over 360 l of blood per hour, 8640 l per day (i.e. 15 t), 3,153,600 l in a year. Throughout life heart of the man misses through itself 224 million liters of blood, and the woman's heart — 249 million, and it is equivalent to an amount of water, vytekayemy of Seine in 10 minutes.

Human heart creates pressure which is enough that blood scattered on seven and a half meters forward.

Therefore it is clear why it is so easy to feel heartbeat. That blood passed on all organism quickly, the big pressure which results from strong reductions of walls of the ventricles pushing blood is necessary.

Energy

Daily in heart there is such power consumption on blood pumping that it would be enough to pass more than 30 kilometers by truck.

During life heart develops the amount of energy comparable with the energy spent by the spacecraft at flight to the Moon and back.

The heart connected to the cardiopulmonary bypass

Quite so bodies before transplantation look.

Heart operations

Main article: Heart operations

Artificial heart

2019: Completely soft heart is printed on the 3D printer

One of problems of artificial heart is that it is very difficult to integrate metal and plastic mechanisms with fabric as they can damage it or blood because of unnatural style of movements.

In May, 2019 heart was created using the 3D-printer thanks to what researchers could make a difficult inner pattern, at the same time using soft and flexible materials. All artificial organ is uniform "monoblock" therefore scientists should not worry how different internal mechanisms are combined with each other (except for entrance and output ports through which blood will come and leave).

In tests the artificial organ proved to be not bad, but scientists noted one important part: meanwhile such heart cannot become a human implant. The matter is that present materials bear only several thousands of blows (it will last approximately for half an hour of work). However in plans of researchers to pick up those materials which will serve much longer.