The world’s smallest heart pump

It is only three millimetres in size, but can pump up to 3.5 litres of blood per minute: the world’s smallest heart pump. The Aachen-based company Abiomed has produced this technical marvel.

After 20 years of development, the heart pumps, even smaller than peas, have been successfully tested on patients in the USA. The small pump, called ECP, can be easily inserted via catheter in practically any hospital. This was not possible until now.

A heart pump with a memory

The trick to the new pump is that it starts off only three millimetres in size but then expands itself to a good six millimetres when it reaches the desired position in the heart.

The construction comprises, among other things, ultra-fast rotating propellers that do the pumping, as well as a special “memory plastic” that can remember its original shape (and size) for a good half hour. This is why the three-millimetre pump cannot be kept in stock. It is always reduced to its mini size just before it is installed.

All its surfaces must, of course, be extremely smooth so that no blood cells are injured. Another important factor is how the mini pump is supplied with energy. Obviously, there is no room for electrics and batteries in the expandable system itself. Instead, the ECP is made to rotate by a 1.2 m long, ultra-thin metal cable. This runs from the femoral artery to the heart and is driven outside the body by a special DC motor – which, in turn, needs a cooling system.

Sounds pretty complex and immobile? Well, it certainly is!

Hope for high-risk patients

But mobility was never the plan. The ECP is only intended to be used for a maximum of six hours. So who will this little miracle actually be used on? For example, in the case of high-risk patients, the mini pump can relieve the strain on the patient’s own heart to such an extent that urgently needed surgery can be carried out – something which, until now, was not possible under the sole strength of the patient’s own heart. The mini heart pump is, therefore, only suitable for temporary use and, after a successful mission, is first pulled through a channel with a fixed diameter – you’ve guessed: the three millimetres again – and then extracted through the catheter.

Incidentally, the world’s smallest heart pump, which was conceptualised in Aachen, was developed to application maturity by a team of engineers in Berlin.

Thank you Abiomed, our heart beats for you!