Method for treating an arteriovenous fistula dilated venous segment in a hemodialysis patient whose arteriovenous fistula exhibits abnormally high venous blood flow or/and pressure. Includes: surgically reconstructing the AVF dilated venous segment, to form an AVF reconstructed venous segment, followed by covering and supporting the AVF reconstructed venous segment with implantable blood vessel external support, such that the arteriovenous fistula will exhibit normal venous blood flow and pressure. Also disclosed is a method for pre-determining an arteriovenous fistula reconstructed venous segment lumen diameter, as guidance for treating AVF dilated venous segments in hemodialysis patients. Also disclosed is use of an implantable blood vessel external support for treating a hemodialysis AVF dilated venous segment. Applicable for preventing or treating various pathological conditions (progressive heart disease, venous aneurysms, venous intimal hyperplasia, venous thrombosis, and bulges of the arm) in hemodialysis patients that are commonly associated with AVF dilated venous segments.
