Two Explanations for the Link Between Stress & Heart Attack.
Scientists may have a better understanding of why ongoing stress raises an individual’s risk of having a heart attack. They believe stress triggers the body to make extra disease-fighting white blood cells, and this can cause inflammation in the arteries of people with a condition called atherosclerosis, where the artery walls are thickened by a buildup of plaque. Other studies suggest that stress causes blood to clot differently. Both factors can lead to reduced blood flow to the heart.
Nature Medicine, June 2014