For someone whose medical practice has had an impact on patients around the world, Dr. Alan Tick Hirsch was too modest to seek attention for it.

“He didn’t tell anybody what he’d done,” said his wife, Sue Duval.

Hirsch helped bring to the forefront the importance of preventing peripheral artery disease. At the same time, he worked so that millions of patients would get reimbursed for treatment for an affliction that affects 120 million people worldwide and often results in leg amputations and death.

Hirsch died April 14 at the age of 62. His cause of death has not yet been determined, Duval said.

The first time Dr. Russell Luepker met Hirsch 30 years ago, the two made an immediate connection. Both came from Boston to teach and practice medicine, and both had a keen interest in treating and preventing diseases of the circulatory system — the ones that cause heart attacks, aneurysms and strokes.

Luepker was impressed with Hirsch’s enthusiasm for and knowledge of the subject. Luepker was 10 years older, but he said Hirsch knew more about some aspects of the field. “His enthusiasm was infectious,” Luepker said. “And it spread to others. It catapulted him to leadership positions in his field.”

Hirsch came to the University of Minnesota after graduating from Harvard. Luepker said he was drawn to Hirsch’s intensity and knowledge of cardiovascular disease, and so he began mentoring him.

Hirsch studied the effect of exercise on improving blood flow to the limbs in hopes of preventing amputations. The field already had a standard of treatment for people with vascular disease, Luepker said, “the plumbing approach”— surgery to install a stent. There was considerable resistance to try something new, Luepker said.

But Hirsch, said Luepker, recognized the possible benefits of exercise in prevention. And he had a nonstop energy to prove it.

Hirsch directed a landmark nationwide trial, the Claudication: Exercise vs. Endoluminal Revascularization (CLEVER) Study, that confirmed those hopes. The results of that study and others, many led by Hirsch, showed that certain exercises were more effective and cheaper at treating peripheral artery disease than surgery.

Duval, a professor at the University of Minnesota Medical School, said Hirsch worked for 20 years to get exercise treatment covered by Medicare, which she said appears to be on track for approval this year.

“That was a dream come true,” Duval said. “He never stopped. He was never going to stop until he got it.”

Hirsch also helped form and lead the university’s program to reduce cardiovascular disease statewide.

“No other state has such a program,” said Dr. Daniel Garry, director of the University of Minnesota’s Lillehei Heart Institute. “It was a bold, audacious idea.”

Hirsch was a founder of the Society of Vascular Medicine in 1989, director of the University of Minnesota’s vascular medicine program, and had taken part in numerous studies published in medical journals nationwide.

“He was a leader nationally and internationally in his field,” Garry said.

Hirsch also maintained a practice at the university, where his patients adored his humor and energy, said Dr. Gary Francis, chief of the university’s cardiovascular division.

Duval said he would often sing songs to his patients, making them up on the spot. He would call them at night and talk to them like friends and family, she said.

“He was just so full of joy,” Duval said.

In addition to his wife, he is survived by his children, Jonathan Hirsch, Rebecca Hirsch and Alex Duval.