Table 1 Trial interventions

ORAH

The skin is incised by scalpel making a 3 cm long incision. The radial artery is dissected free and a vascular clamp is positioned across the artery. If saturation in the index finger on the non-dominant hand is unchanged and the pulsatile flow measured by pulse-oximetry is not compromised, the incision is continued from 2 cm proximally to the wrist and all the way to about 4 cm from the fossa cubiti. The radial artery is dissected free from surrounding tissue by scissors. Side branches are localised and divided by electrical cutters (‘Cautery Forceps’ manufactured by Starion Instruments). When the artery is totally free it is ligated and divided at both ends. The incision is closed with Vicryl 3–0 continuous suture in the subcutis and Vicryl 4–0 continuous intradermal suture.

ERAH

A 2 to 3 cm long incision is made over the radial artery at the wrist on the non-dominant arm. As with the open procedure a pulse-oximetry is placed on the arms index finger. The artery is clamped with a vascular clamp thereby insuring the hand is sufficiently perfused from the ulnary artery. The Maquet Haemopro system (manufactured by MAQUET Gmbh & Co. KG) is then used to dissect the artery free by ligating the side-branches using the Haemopro’s scopical ligating forceps. To free the artery proximally a stab incision is made in the fossa cubiti through which the artery is ligated and divided. The incision in the fossa cubiti is only approximated by Steri-strips but the incision near the wrist is closed with Vicryl 3–0 in the subcutis and Vicryl 4–0 intra-dermally.

Mammario-radial graft

A mammario-radial graft (Y-graft) is performed before extracorporeal circulation (ECC) is begun. When the mammary artery has been mobilised and the radial artery harvested, an end-to-side anastomosis is done with the proximal end of the radial artery being attached to the side of the mammary artery. The anastomosis is sewn with a Prolene 7–0 suture. Free flow through the anastomosis is checked and papaverin solution is applied to the LIMA and radial artery grafts. ECC is begun, the cross-clamp is positioned, and cardioplegia is given. The anastomoses of the radial artery to the coronaries are done from the proximal site going distally. After all radial artery anastomoses are done, the LIMA to LAD anastomosis is performed. After measuring flow in the grafts using ultrasound, the ECC is weaned according to department procedure. Closure and the remaining hospital stay also follow department procedures.

Aorto-radial graft

An aorto-radial graft (free radial artery graft) is performed when the radial artery graft is sewn directly onto the aorta ascendens. This is done after all coronary anastomoses have been completed. ECC is still in effect and a sideclamp is positioned on the aorta ascendens where the cardioplegia cannula is placed. The puncture site for the cardioplegia cannula is also used as the proximal anastomosis site. The proximal anastomosis is done using a Prolene 6–0 suture. Air is removed by retrograde de-airing removing the small vascular clamp positioned on the radial artery graft. The cross-clamp is removed after measuring flow in the grafts using ultrasound and ECC is weaned according to department procedure. Closure and the remaining hospital stay also follow department procedures.