Image of a heart in the chest

Heart disease is still the No. 1 killer of Americans, but decades of progress in reducing deaths from heart disease may have now stalled, according to data released this week.

On Thursday, the Centers for Disease Control and Prevention reported that heart disease remained the top killer in the United States in 2014, accounting for one out of four deaths in men and more than one in five deaths in women.

Yet after years of notable declines, the death rate from heart disease has remained almost flat since 2011, falling at an annual rate of less than 1 percent, found a JAMA Cardiology study published Wednesday. By comparison, heart disease death rates fell by 3.7 percent each year between 2000 and 2011.

Likely to blame, researchers said, are the obesity epidemic and increasing rates of Type 2 diabetes — both risk factors for heart disease.

Although heart disease has been the leading killer of Americans for nearly a century, significant investments in prevention and treatment advances led death rates to fall dramatically over that time. Researchers noted that if the rates of decline from 2000 to 2011 had persisted, deaths from heart disease would have fallen below cancer in 2013.

“Many in the cardiovascular community were poised to celebrate the ‘We’re number 2’ moment,” wrote Donald Lloyd-Jones, M.D., of the Feinberg School of Medicine at Northwestern University in Chicago, in an editorial that accompanied the study. “Heart disease death rates came tantalizingly close to falling to second, and now the gap may be widening.”

Cancer remains the No. 2 cause of death in the United States, followed by chronic lower respiratory diseases, unintentional injuries and stroke. According to the JAMA Cardiology study, stroke mortality declined 4.5 percent each year between 2000 and 2011, but slowed to 0.4 percent a year from 2011 to 2014.

If current trends persist, public health goals set by the American Heart Association to reduce the burden of cardiovascular diseases by 20 percent by 2020 may fall short, the researchers wrote. According to the study, heart disease and stroke death rates would need to fall by more than 2 percent annually — much higher than current rates.

“As a societal imperative, we must redouble our prevention efforts on all fronts,” Lloyd-Jones wrote.

Until patients, doctors, public health officials and politicians are serious about avoiding the development of risk factors in the first place, “beginning in utero and lasting through early childhood well into middle age, we will continue to require more medical interventions, and incur more costs, to curb [cardiovascular disease].”