The main advantage offered by percutaneous TRA is represented by the very low incidence of relevant vascular access site complications and bleeding and allows for early mobilization of the patient and thus to early discharge. As bleeding complications are increasingly recognized as strong and independent predictors of short and long-term outcomes following PCI, TRA may be the preferred access site by experienced teams. Radial artery (RA) cannulation, however, carries a risk of RA occlusion with an incidence of 4.8% to 19%. This is usually of no consequence, because the hand receives blood from both the radial and ulnar arteries (UA) with extensive collateral channels; however, some patients have incomplete palmar arches and might not have adequate communications between the ulnar and radial arteries. In these patients, there is a potential risk of hand ischemia in the event of RA occlusion.