Shocking! The heart is actually a Möbius strip? What’s even more surprising is…

Experts in this article:

Lv Mingming, Master's student in cardiovascular medicine at North Sichuan Medical College

Hu Houxiang, Chief Physician, Department of Cardiology, Affiliated Hospital of North Sichuan Medical College, Professor, Doctor of Medicine, Master Supervisor

If I asked you to draw a heart

Is this your first reaction?

Can you draw one?

But in fact

Heart shape and heart shape

It doesn't matter

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So

What does the human heart look like?

The answer may surprise you...

The heart is a Möbius strip?

Research has found that our heart is a hollow organ, divided into four chambers: the left atrium, the right atrium and the ventricle. However, the shape of the heart is not a simple combination of four chambers, but a spiral Möbius strip.

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As early as the 17th century, people discovered that myocardial fibers run in a spiral shape, and similar findings were found in subsequent dissections, but no one knew where the spiral began and ended, let alone the significance of the spiral structure. It was not until half a century ago that Spanish scientist Torrent-Guasp solved this cardiac anatomy puzzle after dissecting the hearts of nearly a thousand different species.

He discovered that the heart is a wide-noodle-like muscle band that is twisted in a spiral. This myocardial band starts at the root of the pulmonary artery and ends at the root of the aorta. The myocardial band is twisted in a spiral shape to form an 8-shaped figure, which means that the shape of the heart is similar to a Mobius strip twisted three times.

Why is the heart

What about this complex spiral structure?

We all know that structure is the basis of function.

This spiral structure of the myocardium causes the heart to twist when it contracts, thereby actively pumping blood out and into the heart. This twisting deformation is like twisting a towel. Heart contraction is a process of twisting and tightening, while heart relaxation is a process of untwisting in the opposite direction after the twisting movement. From this, we can see that the heart is not as simple as contracting and relaxing like a balloon.

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So how did such a complex heart form?

Torrent-Guasp believes that the development of the heart reflects the evolution of the heart from worms to fish, amphibians and finally mammals 1 billion years ago. For example, around the 18th day of human embryos, a pair of parallel heart tubes will form at the head end of the embryo, and then the left and right heart tubes will fuse into one heart tube, which is the primitive heart, which is similar to the theory that the heart structure is composed of a single muscle band.

The heart tube grows unevenly because each section grows at a different rate. From the head to the tail, there are several enlarged areas, called the glomerulus, ventricle, atrium and venous sinus. In addition to growth, the heart tube also undergoes a series of changes such as twisting, displacement and fusion.

At the beginning of the 5th week, the heart's shape is basically complete, but the four chambers of the heart are not yet completely separated. Next, the heart will continue to complete the internal separation of the atria, ventricles and other structures until the end of the 8th week. If there is an obstacle in the separation process, it will cause congenital heart disease, such as atrial septal defect, ventricular septal defect, etc. Therefore, the 3rd to 8th week of pregnancy is a critical period for the development of the embryonic heart. During this period, if the pregnant woman is infected with certain viruses or exposed to a harmful environment, it may cause obstacles to the development of the fetal heart and form congenital heart disease.

How does the heart beat?

By observing the beating heart, Torrent-Guasp distinguished between two longitudinal movements, shortening and lengthening, and two lateral movements, narrowing and widening, and believed that contraction was propagated from top to bottom along the myocardial band to support this series of mechanical activities.

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Recent studies have found that the electrical signals of a normal heartbeat originate from the sinoatrial node. The sinoatrial node is located in the right atrium at the bottom of the heart. After the sinoatrial node is formed, the electrical signals are transmitted from top to bottom (i.e. from the bottom of the heart to the apex of the heart), causing the atria and ventricles to contract and relax successively, i.e. the beating of the heart. This also provides further support for Torrent-Guasp's view.

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