Mullen | You Can Be Replaced: That’s your heart hollering at you to slow down 

On a warm April day in 1995, he called his wife at her office at 5:10 p.m. He had picked up their two children—ages 7 and 5—at after-school care. He managed to drive the kids the two miles home.

Later he would recount how he wondered, as his vision blurred and the pain in his chest gripped him, if he would black out, roll the car and take his kids to death with him.

They got home. The man told the kids to put away their backpacks. He called 911. Then he called his wife: “Can you come home,” he whispered. “I think I’m having a heart attack.”

When the wife arrived at their home 15 minutes later, her husband was stretched out on the dining room floor, their two kids watching in terror as three EMTs hovered over their dad. Oxygen mask on his face, questions about drug allergies, soothing voices telling him they would take care of him—it all swirled in a cloud of ether around the family.

Ten days later, he underwent triple arterial bypass surgery. Almost 10 years to the day later, there was another bypass. It worked just the way his first cardiac surgeon told him, in the matter-of-fact way your auto mechanic might warn you not to neglect your car’s 60,000-mile tune-up: “You’ll need another one in 10 years. Pay attention.”

There you have it: Life, death and plugging along. Memories of the heart attack survivor I know surfaced after all this time, first, with the sudden death of broadcasting icon Tim Russert, 58, at his NBC office on June 14.

Then three days later, 64-year-old Larry H. Miller—car dealership king, Utah sports empire builder and philanthropist—had his own close call with mortality, most likely related to his Type 2 diabetes, and is recuperating in a Salt Lake City hospital.

When struggling to make sense of these tragedies, people—many of them caring strangers—say, “There were no warning signs.” But those who are closest to hard-driving, Type-A stress magnets like Russert and Miller are just as likely to tell you there were signs, and they showed up long before the breakdown.

Just 24 hours after Russert died, his personal physician revealed some of the

Meet the Press host’s medical history. Russert had coronary artery disease. He took regular medication to lower cholesterol and control hypertension, had even used a treadmill the morning he died. Russert had passed a stress test two months before.

Medical literature calls Russert’s condition “asymptomatic.” Which means no one could have predicted a chunk of plaque would break loose from an artery and stop his heart. Still, the words of everyone who lovingly eulogized Russert offer the subtext by which we might learn something.

Probably missing the irony, ABC’s Sam Donaldson said Russert thrust himself into his work “wholeheartedly.” He added that a person who fights his way to the top of the Sunday morning talk shows, as Russert did, has to work relentlessly to stay there. There’s no guarantee you’ll stay on top, Donaldson said, “except through very hard work.”

Russert scrambled every week to get the top guest, his colleagues recalled. His interview skills were intense, keen. And I wouldn’t be surprised if leading up to his collapse, he looked and felt like hell.

The heart attack survivor I know had the same “asymptomatic” condition. He, too, had a negative stress test days before his coronary.

For years, Miller’s family members have been concerned about his poor health. They have tried to get him to treat his diabetes—manageable through diet, exercise and blood sugar testing. Miller’s oldest son, Greg, told the news media this week “I’m sure he had [diabetes] for a number of years before he acknowledged it to himself.”

Greg Miller, like all loved ones of people who seem bent on working themselves to death, has nagged his dad to slow down. A full 18 months ago, Greg—a fit and avid bicyclist—mentioned Larry’s obsession to work drives him harder than anything else.

While tangentially involved in a cycling event the Miller companies were principally funding, I saw Greg shrug his shoulders, then heard him say of his dad “he won’t take care of himself.”

People who die before their time often believe—mistakenly—they are irreplaceable. For some, 14-hour days are a form of recreation. So you book the best political guest of the week, every week. Then you die at 58. That math is pretty tough to add up.

It could have gone that way for the survivor I know. Instead, he slowed down a bit. He takes his meds. He also took up bird watching, target shooting and walking.

He’s on board, he hopes, for another 10 years. But if he knows anything now, it’s that no one is irreplaceable.