Currently, 15.4 million adults age 20 or older in the U.S. suffer from coronary heart disease (CHD), which is the single largest cause of death in the U.S. and also is the greatest cause of premature and permanent disability in the labor force; CHD is responsible for more than 50% of all cardiovascular events in men and women younger than age 75, and for 1 out of every 6 deaths.