Utility of a Smart Phone Application in Assessing Radial Artery Patency - the CAPITAL iRADIAL Study

Accessing the arteries of the heart through the blood vessels of the wrist is becoming increasingly popular. By obtaining access via the artery in the arm as opposed to the groin, there is less risk of complications and improved patient satisfaction. However, using the wrist can cause blockage of the artery after the procedure. If there is too little blood flow from a second artery that supplies the hand, this could result in significant injury. Therefore, it is important to test these blood vessels in the wrist prior to having this procedure. The best way to evaluate these arteries involves the use of ultrasounds but this takes a long time and is expensive. Therefore, the artery is usually evaluated with a clinical test known as the modified Allen's test, which relies on the doctor watching the flushing of the hand during compression of the artery. Currently smart phones with cameras are able to assess blood flow by passing light through the skin and watching differences in brightness. This may be a better way to assess the arteries in the hand as it is less subjective than simply watching the flushing of the hand. This study aims to assess the ability of an iPhone application in determining whether there is sufficient blood flow through the arteries of the wrist and comparing it to the clinical test commonly used.