AbstractThis study aimed to evaluate the guiding role of left adrenal vein (LAV) for right adrenal venous sampling (AVS). A total of 347 patients who were diagnosed with primary aldosteronism (PA) and underwent successful AVS procedures from January 2020 to July 2021 were retrospectively analyzed. According to the different quadrant position of the orifice of right adrenal vein (RAV), the area where the orifice of RAV is located is divided into three areas: A, B, and C and the area A is further subdivided into A1, A2, and A3 areas. By counting the area where the orifice of RAV is located, the guiding role of the LAV on the RAV is determined. Most of the orifice of RAV are located in area A, and the proportions of areas A, B, and C was 96.8%, 1.4%, and 1.7%, respectively. In area A, areas A1, A2, and A3 account for 80.9%, 17.0%, and 2.1%, respectively. High body mass index, female and smaller the angle between the LAV and horizontal line was associated with the closer positional relationship between the LAV on the RAV. These findings suggest that most of the horizontal position of the RAV orifice is close to the horizontal position of the most distal end of the LAV, which indicate that the LAV location can play an important role on the guiding for right AVS. Additionally, body mass index, sex, and the angle of the LAV was largely related to location of the orifice of the RAV.