Without knowing Lay's medical history, experts are not exactly sure how strong a role either heart failure or stress played in his death. If he had a previous heart attack, for example, this would have placed Lay at greater risk for another one.
Zipes added that it's also possible Lay didn't die from a heart attack but instead from heart failure.
Heart attacks are caused by the blockage of blood flow to the heart -- usually from fat clogging the arteries -- whereas heart failure is a disruption of the heart's electrical rhythm.
Regardless, the important thing to keep in mind, doctors said, is that heart disease is the leading cause of death in the United States.
According to Dr. Clyde Yancy, medical director of the heart failure and transplantation department at the University of Texas Southwestern Medical Center, "We are all at risk, not just CEOs, but the everyday men and women as well."