The mind-body interaction has always intrigued humans. Most people, on the basis of either intuition or personal experience, believe that emotional stress can cause or alter the course of even major physical diseases. Sir William Osler described his typical patient with angina pectoris as 'a man whose engine is always set full speed ahead' and described his patients with cardiac disease as 'worriers'. In recent years there has been tangible evidence for the existence of this interaction however modern medicine is still trying to unravel its intricacies. In this article we review the current knowledge regarding the effect of depression, anxiety disorders and the detrimental effect it has on coronary heart disease. In addition we discuss some of the proven acute psychological triggers for acute coronary syndrome.