Abnormal radial artery in Down syndrome: a rare but clinically important association.

We report a 3-year-old boy with DS in whom radial artery pulsations were incidentally detected to be bilaterally absent. Bilateral ulnar artery and all other peripheral pulsations were normal. His blood pressure in right upper arm was normal, 96/66 mm Hg. Twodimensional echocardiography was normal. Doppler ultrasonography of the arterial trunks of the upper limbs suggested normal ulnar artery waveforms up to the wrist joints and absent radial artery waveforms. Aortogram and bilateral upper limb angiography were performed. This revealed a vestigial right radial artery (absent except in proximal 3 cm) and a hypoplastic left radial artery [Figure 1]. The aortogram was normal and it did not reveal any associated arterial or venous malformations.