Jamie Dimon just turned 70. Here’s how a brush with death reshaped the JPMorgan CEO’s outlook and made him realize he had no regrets

When Jamie Dimon was wheeled into the operating room for emergency heart surgery, he didn’t know whether he would make it out—what he did know was that he had no big regrets in life.

As he turns 70 on Friday, the JPMorgan CEO can safely say he’s had a distinguished career. He has become the face of American banking over his decades-long career—and was even at one point, Wall Street’s savior. He is well-known for navigating the bank nearly unscathed through the 2008 housing crash and...