Influence of Diabetes Mellitus : Diabetes causes micro vascular obstructive disease in heart, kidney, retina and peripheral nerves. Scrupulous rather than casual control of diabetes helps in protecting these organs. Coronary artery and cardiovascular disease are more prevalent in diabetic patients. In diabetics coronary artery disease is more diffusing and the target vessels for grafting usually similar in these patients. Patient's perception of angina is modified in diabetes and they usually come for treatment in more advanced condition. Statistics shows that 25 to 30 per cent of patients coming up for CABG are diabetic. Wyperglycemia has to be well controlled before 'and after coronary artery bypass surgery.