Most people with coronary heart disease can feel healthy for years before they start experiencing symptoms. The most common symptom is a heart attack. If coronary heart disease is not treated, some of the plaques in the coronary arteries can break away and block the blood flow to the heart. Coronary heart disease is the most common cause of sudden death. It is also the most common cause of death in people over 65 years old. Men are 10 times more likely to get coronary heart disease than women.