[Is the Allen test still useful in patients undergoing transradial cardiac coronary angiography?]

The last decade has seen an increasing use of the radial artery access for coronary angiography as it combines low rates of vascular complications and early mobilization. Since its description by Campeau the percutaneous transradial access was associated with low rates of occlusion but although the incidence of ischemia is uncommon, consequences can be disastrous. That's why assessment of collateral circulation of the hand is required. Traditionally the modified Allen test was used as a tool to assess palmar arch collaterals but no consensus exists about its proper role. So the purpose of our review is to see if the modified Allen test can predict ischemic complications of the hand and if it still should be done.