What causes coronary heart disease?

Atherosclerosis. Depends on one's personal risks smoking, obesity, hypertension, hyperlipemia, diabetes , family history. Simply, one blocks the feeding coronary artery to part of the heart muscle and low flow, or no flow causes ischemia which cause death of the heart cells, which is a heart attack! myocardial infarction is the medical term.Ekg and lab tests show the damage.