Discuss the etiology and pathophysiology of coronary  artery disease (CAD)

Inquiry Problem
Discuss the etiology and pathophysiology of coronary 
artery disease (CAD).  Are there links between the
epidemiology and etiology/pathophysiology in CAD?  Is
there a physiological link between CAD and exercise that
manifests in certain symptoms?
In a roughly 3 page essay to address the above
statement/questions.