Heart disease still has a grip on what's killing us, but it's a loose one: 614,348 people in the U.S. died of heart disease in 2014, compared with 591,699 of cancer. This is a big shift from the 1950s, when deaths related to heart disease were more than double of those related to cancer — and an even more radical difference when compared to the start of this century, when only two states, Alaska and Minnesota, saw more cancer fatalities than heart disease.