Swelling of feet after cardiac stenting is considered to be caused by cardiac insufficiency and venous thrombosis in lower limbs. 1. Cardiac insufficiency: after undergoing cardiac stent surgery, the function of the heart decreases, so that a large amount of water and sodium are stored in the body, and the lower limbs are at the weight-bearing place of the body, which will show the symptom of swollen feet after undergoing cardiac stent surgery. 2. Lower extremity venous thrombosis: after cardiac stent surgery, due to prolonged bed rest and lack of exercise will lead to deep vein thrombosis in the lower extremities, and the patient will have the symptoms of swollen feet after cardiac stent. When uncomfortable symptoms appear after cardiac stent surgery, you should go to the hospital in time for relevant examination and give regular treatment after clarifying the cause of the disease.