What Really Triggers a Heart Attack?

Doctors are trying to zero in on heart attack origins but prevention, not prediction, remains the prime strategy for helping patients.

Published: February 16, 2007

For decades, doctors were convinced that plaque-filled arteries narrowed the flow of blood and led to heart attacks and strokes. Todays emerging view, however, is that the majority of heart attacks are caused by plaque that builds up in the arterial walls but does not actually narrow the artery. Rather, this "vulnerable plaque" eventually ruptures, fracturing within the wall and exposing the cholesterol deposits in the plaque to flowing blood.