The Branham-Nicoladoni sign (compression fistula test) is a symptom of congenital arteriovenous fistula. The continued retention of abnormally extensive traffic between the large circulating arteries during the trunk formation phase is called a large arteriovenous fistula. There is still much debate as to what causes the abnormal development of the vascular primordium to form a vascular malformation. Some scholars believe that congenital arteriovenous fistulas are inherited from chromosomal malformations. However, Desaive and Bessone 840 cases of congenital malformations, only 7 cases suggest a genetic history. In early gestation, toxic infections, metabolic disturbances, fetal position and abnormal umbilical cord position causing compression trauma can affect normal fetal development. Deregulation of the endocrine and vegetative nervous systems can also affect the development of the arterial, venous and lymphatic systems. What are the preventive methods for the compression fistula test? Congenital arteriovenous fistula is a congenital disease, so there are no effective preventive measures. The diagnosis requires differential diagnosis with lesions in various areas, as well as prevention of complications. In particular, it is important to prevent the transfer of embolic material through the fistula to cause other embolic diseases. Localized congenital arteriovenous fistulas can be treated surgically with good results. However, most congenital arteriovenous fistulas are very difficult to treat because of the numerous small traffic branches between the arteries and veins and the wide range of lesions, sometimes involving the entire limb, and interventional treatment is sometimes effective. Indications for surgery: 1. Rapidly growing congenital arteriovenous fistulas should be treated by surgery as early as possible, preferably before the age of 6 years in children. 2, with heart failure, lesions involving peripheral nerves or lesions of large scope, vulnerable to injury causing bleeding. 3.Surgical treatment is best for those with slow and limited growth. Forced fistula test patients, pay attention to rest, to a healthy life, exercise, to eat more food containing more minerals. Do not do too intense exercise, try to keep happy and relaxed. Congenital arteriovenous fistula is a congenital disease, so there are no more effective preventive measures, it is recommended that you should do a good job of marriage and pregnancy tests to avoid the birth of affected children, strengthen your physical exercise and arrange your diet rationally.