Observational Study of Radial Artery Patency Following Catheterization With a 7F Sheath

Background:

Coronary catheterization is a commonly performed diagnostic and therapeutic procedure. The procedure is most commonly performed via the transfemoral approach (via the femoral artery). Recently the transradial approach (via the radial artery) has been gaining popularity since it is associated with decreased risk of bleeding and facilitates patient mobilization following the procedure (1-3). During the catheterization procedure a sheath (tube) is inserted into the access artery so as to enable insertion of catheters and devices into the body. Vascular sheaths may have different internal diameters, which are measured in French (F) units. Commonly used sheath sizes for coronary catheterization are 5F and 6F, however use of larger 7F sheaths is beneficial when more complex procedures are performed such as insertion of two coronary stents. Use of a 7F sheath creates a slightly larger orifice within the blood vessel wall and may potentially increase the risk of damage to the vessel wall and hemorrhage.

The palm of the hand normally receives dual blood supply via the radial and ulnar arteries. Prior to performing transradial catheterization the ability of the ulnar artery to supply blood to the whole palm is confirmed by performing an Allen Test, in order to avoid palmar ischemia if the radial artery becomes occluded following the procedure. Radial artery occlusion in the presence of a normal pre-procedural Allen Test is almost universally asymptomatic, however it may preclude future use of the radial artery for vascular access or as a coronary graft if bypass surgery is performed. The frequency of radial artery occlusion following transradial catheterization ranges from 5% to 15% in different reports (4), depending on many factors such patient selection, degree of anticoagulation during the procedure and the time interval between performance of the procedure and studying the radial artery patency. Use of larger sheaths has also been reported as a risk factor for radial artery occlusion (5), however the true incidence of this complication is unclear. It is desirable to discover the true rate of radial artery occlusion following catheterization with a 7F sheath, since such knowledge may assist physicians in planning the optimal catheterization strategy.

Aims:

The aim of the study will be to examine the occurrence of radial artery occlusion following transradial catheterization with a 7F sheath.