Recently, heart attack that caused by coronary heart disease is the major cause of death in U.S.
Another cause that give same contribution as coronary heart disease is angina.
Patients with angina will have not enough blood, and become had the chest pain.

According to the American Heart Association, it is nearly 450K in 2005 for death and 1.1 million for heart attack cases.
Most of the heart attack root cause came from our bad lifestyle.
Obesity or overweight and smoking are main leader of causes for this silent killer.

Current research by SAMHSA (Substance Abuse and Mental Health Service Administration) reported on December 17, 2009, adolescents across all age groups perceive a greater risk to smoking cigarettes than the use of alcohol and other substances including cocaine and LSD.

Nearly 70% of adolescent aged 12-17 perceived great risk from smoking one or more packs of cigarettes per day, and female more likely than males.

The bad news is obesity and overweight also raising to make significant contribution for this complicated disease.
See other report in this site how obesity and overweight phenomenon.

Indirectly, if we see the data from SAMHSA, American youth generation starting to establish silent killer in their next age with their bad lifestyle.
Fighting smoking and overweight is important due maintain our quality of live for better health.
Not only heart attack but also almost all major disease.

Related article: Benefits for quit smoke and how to stop smoking