Regensburg (ddp). The birth cry is usually the first sound of a person – for the first time, breathes the new earthlings air and uses it to get heard. With this cry it should have but still a more mysterious circumstances: it means that come babies with a hole in the heart of the world, which includes the birth cry. A little this story listening to to superstition – something’s there really turn?

«In principle true», says Ernst Tamm from the Chair of human anatomy and embryology of the University of Regensburg: “the so-called foramen ovale in the interventricular septum between the left and right atrium is very important for the baby in the womb. This opening increased the oxygen supply to the unborn. “After the embryonic period, the heart is in principle already designed like the adults, lacking but still breathing via lungs”, Tamm explains. The first breath is a new request to the heart, because the oxygen supply now takes a different approach.

The prenatal heart pumps the blood of the umbilical cord to the placenta of mother. There it is enriched with oxygen and distributed in the body of the child. The post-natal heart must, however, driving two cycles: the right side of the heart is responsible for the pulmonary circulation, the left for the systemic circulation. The blood in the lungs is pumped from the right, from here it flows back then to the left side of the heart, which in turn pushes the oxygen-rich blood to the large body cycle. For the child in the womb, the pulmonary circulation has little meaning. The foramen establishes therefore still a connection between the two circuits oval. The blood thus bypass the pulmonary circulation and from the right directly into the left atrium and the systemic circulation.

«The hole in the partition is set up like a valve» Tamm explains. The walls that limit the hole overlap and open only to a page. Pushes the blood, however, opens the valve to the left atrium and enables the short of the right to the left circuit. This changes with the first breaths: the blood in the right atrium now flows through the right ventricle into the lungs. This outweighs the blood pressure in the left Chamber and automatically pushes the walls of the opening. Usually, they start then with each other to twisted and permanently close the hole. «In some people the walls of the foramen are too short however oval for», Tamm says. This remains an opening and can affect the function of the heart – one of the most common congenital heart disease in humans.