Cardiovascular disorders are disorders of the heart (e.g. coronary heart disease - CHD); of the circulatory system (e.g. high blood pressure); and can cause as strokes (where blood flow is restricted to parts of the brain). These disorders are linked to stress, due to the activation of the sympathetic branch of the autonomic nervous system, leading to an increase in adrenaline. High levels of adrenaline increase heart rate, which causes further strain on the heart. This can lead to high blood pressure, which can cause the blood vessels to wear away. It can also dislodge plaque on the walls of blood vessels, leading to blocked arteries, which can cause heart attacks and strokes.