He invented a successful medical device as a student. Here's his advice for new grads

When he was 25 years old, Thorsten Siess, a mechanical engineering student at the University of Aachen in Germany had an idea: What if there was a way to keep the heart pumping blood during surgery or following a heart attack with a device that affixes a tiny motor to the tip of a catheter?

"This would be able to be put into patients without the need for a major operation," says Siess. "Normally, of course, you would have to split the sternum."

Today, Siess's idea is a reality — a medical device called the Impella — and he serves as the chief technology officer of Abiomed, which is part of Johnson & Johnson.