Aortic anatomy plays a vital role in success of transradial (TR) procedures. The progressively increasing success rate achieved with TR procedures is related directly to the knowledge of possible anatomic obstacles and the appropriate techniques to overcome them.
The ascending aorta – the widest part of the aorta – is a direct continuation of the vestibular portion of the base of the left ventricle. It lies almost entirely within the pericardial sac, coursing vertically with a slight rightwards curve and terminating at the upper border of the second right costal cartilage. The total length of the ascending aorta averages 5 cm- 5.5 cm; however, it is influenced by body stature, diaphragm position and chest conformation. The arch of the aorta originates at the upper border of the right costochondral junction and terminates at the lower border of the body of the 4th thoracic vertebra. The arch has a U-shaped curvature due to a gentle upward curve, posterior and to the left. In an average adult <60 years of age, it measures 4.5 cm in length and 2.5 cm-3 cm in diameter. In patients >60 years of age, arch diameter of 3.5 cm is considered within normal limits.