From a joke about making 'nano cauliflower' to a real discovery. Mario Castro tells DW how a pan-European consortium cracked the code of the fractal patterns that make up cauliflower.
The heart is a pulsating miracle
Refined suction and pressure pump
The heart beats incessantly. But how does it work? And how can modern medicine repair a defective heart? It's a fist-shaped, hollow muscle that contracts about 70 times every minute. It pumps up to 10,000 liters of blood per day through the body - if necessary it can pump even more blood - in fact, five times as much when you jog.
The heart is a pulsating miracle
Double the work
Our hearts consist of two pumps – not just one but two. The right ventricle pumps blood into the lungs where the blood is filled with oxygen. At the same time, the left ventricle pumps the same amount of blood into our body's circulation system. It's no simple task. The pressure in the body's main circulation is higher than in the pulmonary system.
The heart is a pulsating miracle
And the beat goes on
Each half of the heart consists of an atrium and a ventricle. Blood only flows in one direction due to the heart valves (green), which function as non-return valves. They are located between the atria and the chambers, as well as between the chambers and the adjoining vessels.
The heart is a pulsating miracle
True muscle
The heart is just a muscle - but a very special one. It's like a muscle in your arm or leg. It contract just as fast and powerfully. But the heart is particularly durable and doesn't suffer from fatigue. All heart muscle cells are coupled together so that the organ contracts as one.
The heart is a pulsating miracle
Natural pacemaker
It's impossible to will your heart to stop beating because it isn't controlled by the nervous system. It responds to its own clock. Special muscle cells in the sinus nodes produce a small and regular electrical pulse that spreads quickly throughout the heart to allow it to contract. If the sinus node fails, the atrioventricular (AV) node takes over.
The heart is a pulsating miracle
Heart skips a beat
If the heart loses its rhythm, for instance, through ventricular fibrillation, it's unable to relax and remains cramped. Then it stops pumping blood. A shock sensor known as a defibrillator can be used to interrupt this life-threatening situation and allow the heart's natural clock to take over again. Anyone can operate a defibrillator.
The heart is a pulsating miracle
Lifesaver
An artificial pacemaker can help a patient whose heart beats too slowly. The device generates electrical impulses and transmits them to the heart. Surgeons implanted the first pacemaker in 1958. Modern pacemakers will function for five to 12 years - on average, they last about eight years.
The heart is a pulsating miracle
On an open heart
Before operating on a heart, surgeons have to stop it and shut down circulation - like death itself. Scientists resolved the problem in the 1950s with the development of the heart-lung machine. The device takes over the function of the heart and lungs for a short period, enriching the blood with oxygen and pumping it through the body.
The heart is a pulsating miracle
Through the groin to the heart
Modern medicine makes it possible to examine the heart or operate on it without having to open up a patient's chest. The surgeon inserts a cardiac catheter - a thin plastic tube - through the groin, elbow or wrist, and guides it through veins and arteries to the heart. The patient requires only local anesthesia.
The heart is a pulsating miracle
Foldable heart valves
If a heart valve fails or is worn out, it has to be replaced. Surgeons can use pork as an organic substitute or a mechanical heart valve made of metal. There are also foldable, artificial heart valves (see photo). Because you they can be folded, they can be inserted in a minimally invasive way via a catheter, allowing the patient to avoid open heart surgery.
The heart is a pulsating miracle
Clogged arteries
Coronary arteries supply the heart muscle with blood, with nutrients and oxygen. When the vessels become clogged, the tissue dies, resulting in a heart attack. Surgeons can bypass the restricted point (marked green in this graphic) by using a redundant vein or a vascular prosthesis made of plastic.
The heart is a pulsating miracle
Metal support
If a coronary vessel becomes constricted, surgeons can insert a catheter and dilate the constricted point with a balloon. A stent is used to prevent the vessel from contracting. Stents are fine tubes made of metal to support blood vessel walls from the inside.
The heart is a pulsating miracle
A second life
Surgeons performed the first heart transplant in 1967. The procedure was a sensation at the time, but it's very common today. Every year, surgeons transplant thousands of hearts donated by people who have died. But recipients have to take medication for the rest of their lives to prevent their bodies from rejecting the foreign organ.
The heart is a pulsating miracle
Pump it up!
But heart donations are rare. If a person's own heart fails, there are cases where it can be supported with an artificial heart. The person keeps their own heart, but it is supported with an implanted pump.
The heart is a pulsating miracle
Heart of brown plastic
Scientists are working on an artificial heart, which they hope will be able to completely replace a patient's diseased heart. The device has been tested successfully in an animal study with a calf.
