[Choice of an alternative access in failed endovascular intervention through the right radial artery]

The transradial access has deservedly become the 'gold standard' while performing various X-ray endovascular interventions both diagnostic and therapeutic ones. However, along with all its advantages, it is not without disadvantages. These difficulties for the most part are related to peculiarities of the anatomy of upper-limb arteries. It is exactly complex anatomy that is the most common cause of complications and compelled change of the access while using the right radial artery. The purpose of our study was to examine the symmetry of complex anatomy of upper-limb arteries in order to choose an optimal and safe way of conversion of the access in case of forced refusal from the right radial access. For this reason there was developed an open multicentre registry acronymized as COMPAAS (COMPlex Anatomy of Arteries and Symmetry). During the work of this Registry from February to December 2018, correspondents of the study became 35 colleagues from 23 clinics of 11 cities of Russia. The working group analysed a total of 127 patients presenting with 157 variants of complex anatomy of lower limb arteries: high bifurcation of the radial artery (84), complete loop or tortuosity (66), and compartmental calcification of brachial arteries (7). The anatomy of arteries on the opposite upper extremity was studied based on angiographic findings. The most frequent variant (84 cases) of complex anatomy was high bifurcation of the radial artery at the level of the a. brachialis (20.9% of cases), with the origin of the brachial artery at the level of the a. axillaris being revealed half as often (9.9%). The maximum percentage of symmetry was observed in the group of patients presenting with compartmental calcification of upper-limb arteries (85.7%). Complete loop or marked (more than 100°) tortuosity of arteries on both arms was revealed in 54% of cases. Besides, in 25% of cases, tortuosity was combined with the high origin of the radial artery. It is noteworthy that none of the 127 patients appeared to have complex anatomy on the a. ulnaris. When revealing pronounced calcification of arteries of the forearm or a combination of high bifurcation with tortuosity, it seems feasible to decide upon conversion of the access to the femoral one (a. femoralis) or ulnar (a. ulnaris). In isolated high bifurcation on the right, effective conversion to the contralateral (left) radial approach is possible in not less than 75% of cases.