Edema of the lower limbs has a certain relationship with the heart, but it may also be caused by physiological factors, liver disease, kidney disease and so on. 1. Heart disease: if you suffer from pericarditis, right heart failure, myocardial sclerosis, pericardial effusion and other diseases, it is easy to affect the venous blood return of the lower extremities, the phenomenon of lower extremity edema, known as cardiogenic edema. 2. Physiological factors: if long-term high salt diet, long standing and sedentary, drinking a lot of water before going to bed, etc., it may cause water to gather in the lowest place of the body, resulting in lower limb edema symptoms. 3. Liver disease: when there is portal hypertension, cirrhosis, liver cancer, hepatic lymphatic fluid reflux obstacle, etc., which leads to hypoproteinemia and lower limb edema, it is called hepatogenic edema. 4. Kidney disease: if you suffer from nephrotic syndrome, nephritis, hypertensive nephropathy, etc., it will easily cause renal dysfunction, and even renal failure, resulting in lower limb edema, which is called nephrogenic edema. In case of lower limb edema, you should go to the hospital in time, and give appropriate treatment and therapy after clarifying the cause of the disease.