Abstract： Background The radial artery is currently regarded as a useful approach for coronary intervention procedures. Adequate anatomical information of the radial artery should be helpful in performing transradial coronary procedures. Few data about the Chinese population have been obtained in this field. Therefore, we tried to evaluate the incidence and clinical significance of anomalous patterns, and their influence on the intervention procedure.Methods In an estimated sample of 3000 cases, radial artery and subclavical artery angiography were performed after insertion of the sheath and coronary angiography (CA). The evaluable data including branch anomaly, tortuosity of the radial artery and procedural characteristics were analyzed. The procedure success was defined as CA or percutaneous coronary intervention (PCI) completed with the initial radial artery approach without changing to other routes.Results In this study, 1897 cases of CA was undertaken and 1103 cases of CA combined with PCI were performed.The success rate of transradial intervention (TRI) was 96.6% (2899/3000). The approach in 44 cases was changed to the contralateral radial artery and 57 cases were changed to the brachial artery or femoral artery due to failure with the initial radial artery approach. The angiography of the upper limb artery was performed in all cases. Anatomic variations of upper limb arteries were noted in 610 patients (20.3%), which included tortuous configurations of the radial artery (5.0%), hypoplasias (2.2%), radioulnar loop (1.1%), abnormal origin of the radial artery (7.7%), stenosis of radial artery (1.4%), a tortuous configuration of the brachial artery (0.9%), a tortuous configurations of the subclavian artery (1.9%), lusoria subclavian artery (0.1%), and subclavian artery occlusion (0.03%). The procedural success rate in the normal population was higher than in the variation group (97.6% vs 93.0%, P<0.001). In addition, other procedural outcomes and incidence of complications except radial artery occlusion were also significantly superior to variation group.Conclusions Anatomic variations of the radial artery were common, making up an important limitation in the trans-radial approach. Selection of appropriate instruments and understanding some tips and tricks were helpful to overcome the obstacles and effectively reduce the learning curve.