Hand circulation after radial artery harvest for coronary artery bypass grafting.

Despite wide spread use of the radial artery (RA) graft for coronary artery bypass grafting, the change of hand circulation after RA harvest has not been fully clarified. Severe hand ischemia such as resting pain or gangrene is a rare complication and has been reported in 4 patients. These cases resulted from occlusive artery disease in forearm, which should be carefully explored before RA harvest. Incidence of mild hand ischemia such as hand claudication or fatigue is unknown, but our study suggested that around 10% of the patients developed mild hand ischemia after RA harvest. The blood flow to the forearm territory was decreased by 20% after RA harvest despite the compensatory dilatation of ulnar artery. The presence of low perfusion in the affected hand has been pointed out in some studies. We reported the decreased tissue oxygenation of the affected hand during hand grip exercise. The Allen test is the most popular preoperative screening method, but is associated with considerable numbers of false-positive and false-negative results. Full length scanning of ulnar artery by ultrasonography seems to have a lower false-positive rate. But further clinical experience is necessary to establish a more reliable screening method.