Fundamental issues to be addressed before and during a transradial procedure.

The transradial approach (TRA) is being increasingly adopted in Europe, and is currently implemented in 60% of angioplasty procedures in France. This vascular route improves the comfort of the patient as well as that of the paramedical staff whilst allowing a reduction in hospitalization duration and cost. Most importantly, it reduces the risk of vascular and bleeding complications with a potential impact on mid-term mortality. With the classical transfemoral approach, certain patients are more prone to access site complications (elderly patients, women, severely obese patients). These population is also the same in which the TRA is the most difficult to perform. For this reason, operators are advised to start their learning period with the easiest cases: a palpable radial artery in a young patient in a non-emergency setting. Though the radial artery is a small vessel, slightly less than 3 mm in diameter, it is large enough to accommodate devices for simple and complex angioplasties such as bifurcations with kissing balloons, rotablator procedures and saphenous venous graft angioplasty with distal protection devices. A negative Allen test used to be considered an absolute contraindication to the TRA. In fact, assessment of the palmar arches using pulse oxymetry examination is now recommended. It is more sensible and less frequently negative. However, given the low risk of radial occlusion and the extremely low morbidity rate, the patency of the palmar arch is less frequently tested in "radial" centres. The TRA is already the gold standard approach in some countries in Europe. It requires specific practice in order to avoid a number of pitfalls such as spasm, which can be almost completely avoided by a good prevention, anatomic difficulties, which can be easily solved by a good knowledge of anatomic variations.