Coronary perfusion pressure (CPP) refers to the pressure gradient that drives coronary blood pressure. The heart's function is to perfuse blood to the body; however, the heart's own myocardium (heart muscle) must, itself, be supplied for its own muscle function. The heart is supplied by coronary vessels, and therefore CPP is the blood pressure within those vessels. If pressures are too low in the coronary vasculature, then the myocardium risks ischemia (restricted blood flow) with subsequent myocardial infarction or cardiogenic shock.