Based in the Lausanne region since the 1970s, the entrepreneur has revolutionised care for multiple diseases via his inventions.
At age 90, Hans Wallstén has not lost an ounce of enthusiasm. Sitting at his desk in Paudex (Vaud), overlooking the lake, he calmly recounts the steps in his career. Opposite him, small, carefully labelled and organised boxes contain models of his greatest invention, the stent – a major medical innovation. The tiny metal device is implanted in the body without surgery. It is used to stop the narrowing (stenosis) of a cavity in an organism, such as a coronary artery to prevent a heart attack, for example. “Several variations of the stent have been developed since my invention in the 1980s,” says the native of Sweden. “Today, an estimated two million stents are implanted worldwide every year.”
Though nearing retirement, the inventor kept his creativity flowing.
Originally, this graduate of Chalmers University of Technology worked in a sector very different from medicine. “Until age 45, I had a career in the paper industry in Sweden,” he says. “I developed several processes to improve paper manufacturing. Then I ran a paper mill for several years.” At the end of the 1960s, the Swedish Bonnier Group contacted him, offering him funding to set up a company to market his inventions. Hans Wallstén accepted, and that is how his first company, Inventing, came to be. “I set it up and successfully developed it in Sweden for five years before coming to Lausanne in 1973 to create another development centre,” he says.
The device met with resounding success. By 1989, 1,200 Wallstents had been implanted. That same year, Medinvent was sold to US pharmaceutical giant Pfizer.
He stumbled into the medical field by chance. “In 1979, Zurich-based cardiologist Ake Senning asked me to collaborate on a project to develop a spiral-shaped prosthesis to prevent stenosis. But the device wasn’t effective.”
Research continued at Inventing, and Hans Wallstén designed a self-expanding metal meshwork tube. He filed a patent for the implant in 1982 and, with financial backing from Bonnier, founded the company Medinvent in Villars-Sainte-Croix to develop the invention.
Following a number of tests on animals, this initial stent, dubbed the “Wallstent”, was implanted through a catheter in the small coronary arteries of a human patient for the first time ever in 1986 at Toulouse University Hospital, then at the Lausanne University Hospital. The device met with resounding success. By 1989, 1,200 Wallstents had been implanted. That same year, Medinvent was sold to US pharmaceutical giant Pfizer.
Though nearing retirement, the inventor kept his creativity flowing. He tackled the problem of menorrhagia, heavy menstrual bleeding that affects one in ten women and requires surgery and hospitalisation. Hans Wallstén then developed “Cavaterm”, a solution used to treat menorrhagia in 15 minutes using a heat balloon. The entrepreneur started his last company, Wallstén Medical (now Veldana Medical), in Morges. Even since then, Hans Wallstén has not stopped inventing. He recently applied for a new medical patent. “I will never stop thinking about how to innovate,” he says. “My job is my only retirement hobby.”
Several variations of the stent have been developed since my invention in the 1980s. Today, an estimated two million stents are implanted worldwide every year.