The size and length of the wound after the saphenous vein is harvested for coronary artery bypass surgery is a common cause of abnormal wound healing (surgical site infection – SSI), extends the treatment process and the patient’s stay in the hospital, and significantly increases the cost of treatment. Many factors influence SSI. The main one is peripheral arterial disease (PAD; lower extremity artery disease). Peri­pheral arterial disease is common but unfortunately diagnosed rarely and often late. Its occurrence and consequently impaired blood supply to the lower extremities has a significant impact on the occurrence of SSI after the saphenous vein is harvested. An effective, simple, cheap, and common diagnostic solution for PAD in patients qualified for coronary artery bypass grafting may be the use of the ankle-brachial index in everyday practice.