'Monk' Actor Jason Gray-Stanford on His Heart Transplant Miracle: 'A Light in Me Was Almost Out'

While home for the holidays in December 2019, actor Jason Gray-Stanford was ending the decade on the healthy note that had become his routine: a low-salt breakfast, brisk walk with his dog Woodford in a park near his family's Vancouver, Canada home, then a spin class.

At 49, the LA-based Monk star had been diligent about managing the heart failure his doctor diagnosed in early 2018. (Heart failure means the heart is not pumping as well as it should, and it's a chronic, progressive condition.) He changed his diet, took his medications and adjusted his workouts. "I was doing what I could to keep the life I liked to lead," he tells PEOPLE in this week's issue.

And on that Dec. 30 morning, it all seemed to be coming together as he strode into an Equinox and mounted a spin bike for class.

"I was feeling fresh," he recalls. "Fifteen minutes later I woke up on the floor with all the gym eyes on me. It wasn't just embarrassing; it was a sign that something was definitely wrong."

It was the first troubling sign leading to the shocking news 10 months later that his heart and kidneys were in complete failure, he'd need an immediate heart transplant or he'd be dead within a few months — and that a matching donor had miraculously become available that day.

Since the Nov. 12, 2020 transplant, Gray-Stanford, 51, has made a full recovery. "This gift I've been given has relit a light that was almost out.," he says.

Until now he's only shared the news of his transplant and diagnosis with close family and friends. He's speaking up to help raise awareness for organ donations and cardiovascular health, and to encourage people to sign up as organ donors.

"I am so fortunate and so grateful that I was able to receive this transplant," says the actor. "If there's a modicum of inspiration someone can take from what I've gone through, then it's my job to get out there, and say something. It's as close to a miracle as you get."

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Of his eight-year run on Monk, the comedy "was a delight in all ways," he says. "Pretty lucky guy I was."

For the next several years he worked on a series of other shows. It was towards the end of 2017 when Gray-Stanford was in Vancouver shooting a guest appearance for X-Files when he felt an unusual sluggishness during workouts.

"I was worried because I wasn't performing at my peak and I didn't understand why," he says. "I assumed I was run down and would bounce back."

But he didn't, and soon after in January 2018, saw a doctor who discovered his heart was "in a very crazy arrhythmia." Says Gray-Stanford: "I felt panic."

That discovery led to a hospitalization and diagnosis of heart failure and a small blood clot in his heart. "My reaction was, 'No way,'" Gray-Stanford recalls. "'This doesn't happen to me, absolutely not.' It was surreal."

Stabilized with blood thinners and diuretics, he later returned to Los Angeles and underwent a battery of tests uncovering its cause: idiopathic dilated cardiomyopathy. While doctors suspect a viral infection triggered it, "we don't know for sure," says his doctor, Mustafa Toma, medical director of the heart transplant service at St. Paul's Hospital in Vancouver.

Gray-Stanford never imagined doctors would be informing him that his kidneys and heart were completely failing. "They said, 'You got two choices, we can start the heart transplant process and hopefully get you a new heart or you're dead, you're looking at another few months,'" he recalls. "It was surreal, it hit me so hard."

Astonishingly, later that day, a doctor announced a heart was coming in and that "it is an incredible match for you,'" Gray-Stanford recalls. To find such a match so quickly, says Toma, is "highly, highly uncommon. It is amazing. Some patients end up waiting two or three years to get a heart transplant, unfortunately."

His prognosis is "quite good," says Toma.

"Every day that I get is so important to me now," says Gray-Stanford, who is teaming up with the American Heart Association. "I don't know how many I got left. But I'm certainly going to attack each one with as much spirit as I possibly can."