The heart of innovation: How bold questions transformed heart surgery at the University of Minnesota

Not long ago, the human heart was considered untouchable. If there was a problem with someone’s heart, fixing it was a surgical feat most doctors would not attempt.

That changed at the University of Minnesota, where surgeons, engineers, and researchers began tackling problems that stood in the way of operating on a beating heart. Their work laid the foundation for modern cardiac care and reshaped medicine.

When heart surgery became possible, new questions followed

For Javier Navarro Rueda, PhD, assistant professor in the Department of Surgery and a member of the University of Minnesota's Visible Heart Lab, progress in heart surgery is best understood through the questions it created.

“How do we slow the heart? How do we stop it? How do we restart it? How do we return to normal pacing and maintain it?” he said, noting that every hurdle that followed became a clinical or engineering problem to solve.

Beginning in the 1950s, those questions shaped a series of breakthroughs, one problem at a time.

Building a hospital for the impossible

In 1951, the University opened the Variety Club Heart Hospital, the first heart-focused hospital in North America. At a time when heart surgery was still rare and dangerous, it gave surgeons a dedicated place to test bold ideas and gave patients new hope.

How slowing the heart made repair possible

One of the first major barriers was time. In 1952, University of Minnesota surgeons F. John Lewis and Richard Varco performed the first successful open-heart surgery using deep hypothermia. By carefully cooling the body, they slowed the body’s need for oxygen and created a brief but critical window to open and repair the heart.

Stopping the heart without stopping life

Some heart conditions required the heart to be completely still. To solve that problem, University of Minnesota heart surgeon C. Walton Lillehei developed cross-circulation, a technique that used a parent as a living heart-lung machine for their child. While lifesaving, the approach carried serious risks for both patients.

Seeking a safer alternative to the risks of human donors, Dr. Lillehei and colleague Richard DeWall introduced the DeWall-Lillehei bubble oxygenator in 1955. This breakthrough replaced complex and expensive hardware with an elegant, disposable system of plastic tubing that safely oxygenated a patient’s blood while their heart was stopped. Looking back, Navarro Rueda notes that breakthroughs like this only happen when medicine and engineering move forward together.

The design that set a global standard

By the 1970s, heart surgery had shifted toward long-term survival. In 1977, University doctors helped implant the first successful St. Jude Aortic Valve. Its durable two-disc design allowed blood to flow more naturally and reliably, and it became one of the most widely used artificial heart valves in the world.

Keeping pace

In 1957 a blackout shut down wall-powered pacemakers at the University of Minnesota. For nearly three hours, staff rushed to keep their young patients alive using emergency drugs.

The crisis pushed Lillehei to turn to Earl Bakken, who built the first portable, battery-powered pacemaker. The shift from wall power to battery power transformed cardiac pacing and helped fuel the growth of the company Bakken founded, Medtronic.

From historic firsts to future cures

That same problem-solving culture continues today in places like the Visible Heart Lab. Even when current technologies work well, progress never stops.

“If the current devices work, we are already thinking two or three versions ahead to improve them,” Navarro Rueda said.

The next breakthrough in heart care may begin with research happening today and with people willing to take part in studies that move medicine forward.

Want to get involved? Explore research studies on StudyFinder to see where you might be a fit.