Subclavian artery steal is staged according to the ultrasound results. According to the relationship between the direction of subclavian blood flow and systole and diastole of the patient, subclavian artery steal can be graded into four levels.
1. Grade I: Grade I is hidden blood theft, which is manifested by reduced systolic blood flow velocity in the vertebral artery.
2. Grade Ⅱ: Grade Ⅱ is early transient blood theft, with bi-directional blood flow changes, mainly positive, negative in systole and positive in diastole.
3. Grade III: Grade III is late transient blood theft, mainly manifested by bidirectional blood flow, mainly in the negative direction, negative in systole and early diastole, and positive in late diastole.
4. Grade IV: Grade IV is complete blood theft, and the direction of blood flow is completely negative.
It is recommended that patients suffering from subclavian artery blood theft should go to the hospital for examination in time and actively cooperate with the doctor’s treatment.