BOSTON — Born with a heart defect, Bouba Dieme knows a heart transplant is a long shot.

But thanks to recent medical advances, Dieme, 32, received an LVAD implant while waiting on the transplant list, and expects to live a longer, healthier life because of it.

That’s why he walks.

Dieme, who lives in Milton with his wife and three children, had the procedure 18 months ago, which saw a battery-operated, mechanical pump-like device implanted in his chest to maintain the pumping ability of his heart. On Saturday, he led a team at the Boston Heart Walk for the second year in a row.

“It’s great being able to be part of this and raise awareness in any way,” he said. “My LVAD is very new technology, and that’s thanks to the research the American Heart Association funds.”

Dieme’s team, Heart of a Giant, and thousands of others raised more than $1.2 million for the Boston Heart Walk, an annual American Heart Association campaign to help fight heart disease and stroke.

“I’m excited about what our contribution today will do for the next generation,” Dieme said.

Heart of a Giant, a Boston Heart Walk team led by Bouba Dieme, of Milton, poses for a group photo at the Hatch Shell.

The annual event, which started at the Hatch Shell and featured 1, 3 and 6-miles routes along the Charles River Esplanade, brought together companies, medical professionals, community volunteers, survivors, and many more people who are impacted by heart disease and stroke.

Kaitlyn Clark, of Weymouth, was determined to help the fight against cardiovascular disease after her father Kevin died of a heart attack four years ago, at age 57.

“I forced my family to get involved in the cause,” Clark said.

The family doubled their efforts last year, when Clark’s brother lost a close friend to a heart attack. Clark said their tie-dyed shirts were two colors this year, to represent their two angels.

This story is far too common. Despite positive trends over the decades, cardiovascular disease is still the number one cause of death in the United States, claiming more lives than all cancers combined.

Each day, about 2,150 Americans die from heart disease. Stroke, the nation’s No. 5 killer and the leading cause of severe disability, claims the lives of nearly 219,000 people each year.

Nobody is more aware of these sobering statistics than Randolph resident Barbara O’Malley, who lost her father to complications from open heart surgery in the same year she had to have a similar surgery. Two years ago, O’Malley’s mother suffered a stroke.

Cardiovascular disease “runs in the family, I guess,” O’Malley said at Saturday’s walk.

She was walking with her children and grandchild this year, as part of team Heartbeats for Babs.

Though the team was named in her honor, O’Malley said they weren’t walking just for her.

“I’m walking for everybody here,” she said. “For every survivor.”

Team Heartbeats for Babs, comprised of Barbara O’Malley (far right), with (from left) Alexandra Hall, Kayla Caron (O’Malley’s daughter), Bo Caron (her grandson) and Nick O’Malley (her son).

Fellow survivor Shannon Heafey, a Tewksbury native who lives in Charlestown, said she was inspired by the “support system” at the walk.

“It’s cool to see organizations and communities that stand behind you,” she said, gesturing at the thousands of enthusiastic, colorfully-dressed walk participants around her.

Heafey was one of several survivors to speak at the walk, telling her story of a congenital heart defect and 18 heart surgeries throughout her childhood. She was introduced on stage by event emcee Emily Riemer, an anchor at WCVB NewsCenter 5, as someone who has been “fighting to beat the odds” since birth.

“I definitely had to grow up quick,” she said.

Shannon Heafey, a Tewksbury native who lives in Charlestown, was one of several survivors of heart disease to speak at the walk.

Another congenital heart defect survivor, 11-year-old Eva Gambon, was represented at the walk by her 6-year-old friend Alexander Vasquez.

Gambon, of Rockport, couldn’t be at the walk because she recently had her seventh heart surgery. Vasquez was thinking of her throughout the day.

The Malden first-grader was leading a team of 22 people, said his mother, Jessica Vasquez. Her son learned about congenital heart defects last year in school.

“I wanted to help by raising money,” he explained.

Alexander Vasquez, 6, of Malden, was at the walk to support his friend and congenital heart defect survivor, Eva Gambon, of Rockport.

Another young team leader and first-time walker, Brockton resident Josie Pina, turned three this year.

Pina, who had open heart surgery at seven weeks old, has had “phenomenal” health since then, said her mother Delilah Pina.

Delilah Pina heard about the Boston Heart Walk last year. She got 16 friends and family members on board for Team Josie Strong.

Seeing the walk for the first time, “I’m so amazed,” Pina said. “There are so many people coming out, and so much money being raised.”

The Boston Heart Walk is among 300 Heart Walks held in communities across the nation. Nearly one million people walk each year for a singular mission, to cure heart disease and stroke.

Over the past 25 years, the American Heart Association and the American Stroke Association have funded $3.4 billion in research, which has led to many breakthroughs in the understanding and treatment of these diseases.

Delilah Pina, of Brockton, with her daughter Josie, 3, who had open heart surgery at seven weeks old.

Holliston residents Wendy and Jim Bruno understand better than most that this research, sadly, can mean the difference between life and death.

Their son, Gregory, died at age 18 from a virus-caused heart condition he didn’t know he had. This year, a decade after Gregory’s death, his parents formed team Gregory’s Goalies to raise money in honor of their soccer-loving son.

“It’s wonderful to have everyone here,” Wendy Bruno said, her son’s face smiling from each team member’s t-shirt. “I love looking at the shirts and seeing all these Gregorys.”

They were walking not just for Gregory, but for other families, too.

“If enough research is done, they may be able to catch these things in the future,” Bruno said. “That’s the hope.”

Wendy and Jim Bruno (center) of Holliston, with their team, Gregory’s Goalies, named for their son who died at age 18 from a virus-caused heart condition.

If you would like to make a donation to the Boston Heart Walk, please visit bostonheartwalk.org.