Long-term digital blood flow after radial artery harvesting for coronary artery bypass grafting

The radial artery is widely used as a bypass conduit in coronary artery bypass surgery, but the long-term flow readjustment in the hands and fingers induced by the removal of the radial artery is poorly understood.

Using pulse-volume-recording plethysmography, digital blood flow was measured semiquantitatively in 24 patients immediately after harvesting of the radial artery for coronary artery bypass grafting (short-term group) and reassessed in 15 of these patients 3 years later (long-term group). Measurements taken from the fingers of the operated arms were evaluated and compared to those taken from the opposite or control arms. The short- and long-term changes in digital blood flow were also compared.

Postoperatively, there was an overall decrease in blood flow to all the fingers of the operated arms. There was also evidence of redistribution of digital blood flow favoring the thumb and index finger over the fourth and fifth fingers, with the same distribution pattern seen in the fingers of control arms. Over time, the digital blood flow in operated arms recovered to levels similar to those in control arms.

The study showed that there was an overall decrease in digital blood flow following radial artery harvesting. The resulting blood supply in the remaining ulnar artery still provided more flow to the thumb and index fingers than to the fourth and fifth fingers, indicating the existence of an autoregulatory mechanism operating to satisfy the physiologic needs of the fingers. The long-term results showed that the overall decrease in distal blood flow immediately after radial artery harvesting was significantly recovered by physiologic adaptation.