Nearly Half of All Heart Attacks Don't Have Symptoms

Silent heart attacks, which have no symptoms but still involve a loss of blood flow to the heart, make up 45% of all heart attacks and triple the chances of dying from heart disease, according to a study published Monday.

The study, published in the American Heart Association's publication Circulation, found that silent heart attacks make up nearly half of all heart attacks and increase the chance of death by all causes by 34%.