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Royse et al. Vessel Plus 2020;4:5 I http://dx.doi.org/10.20517/2574-1209.2019.34 Page 13 of 22

Radial artery harvest
The key to simple RA harvest is to enter the correct anatomical plane, which is within the fascia
immediately surrounding the superficial radial nerve, radial artery and veins. Here, the RA lies in loose
areolar tissue and can be harvested with its two satellite veins with the minimum of dissection.

Tips: Please do not include surrounding tissues such as additional deep fascia, muscle or tendon fragments,
as this increases the trauma to the forearm without benefit. Specifically, such a harvest has no advantage for
influencing spasm.

An alternative is endoscopic harvest of RA and it is not recommended that this technique is used in the
initial experience. The open technique will provide for a clear understanding of the anatomy and minimise
any risk to the RA or forearm structures [Video 1].

Tips: Division of the proximal end of RA can be undertaken with metal clips or suture ligation (the
latter recommended in the initial experience). No separation of the satellite veins from the RA should be
performed prior to proximal division, as this often causes spasm of the proximal 1 cm of RA. However,
separation of the veins after division does not cause spasm, and the reason for this is not apparent.
Generally, spasm is less common or severe than that seen in the distal segment of the IMA and treatment is
the same, with use of papaverine and rarely use of a metal probe.

RA may be stored with the usual preparation used by the surgeon for IMA. The author uses 1% papaverine
with heparin and no blood, whereas others may dilute the solution with some blood of similar volume.
There is no convincing evidence of efficacy superiority for any method.

Grafting aorta-coronary with radial artery (keep it simple)
Using the same suture technique and suture material, as is the normal practice of the surgeon when grafting
with SVG, should result in the same technical result as is their usual practice.

Tips: The RA is easier to use than SVG as it has a thicker wall and is more elastic and so less prone to
kinking if it is of redundant length. A minor technique difference of the distal anastomosis is that the RA
does not require the construction of a “hood”. For SVG to adopt a satisfactory lie without flattening over
the toe (distal) region of the anastomosis, it is common for surgeons to leave some of the SVG redundant
so that a rounded “hood” is created. This occurs when the conduit anastomosis area is larger than the
coronary anastomosis area. This is not necessary for all arterial conduits, and exact size matching is
preferred and does not ever lead to restriction at the anastomosis.

The proximal anastomosis to the aorta is constructed as for an SVG anastomosis with the same suture
materials (e.g., 6O Prolene). No SVG intermediary hood between the aorta and the RA, or any alternative
anastomosis method, is required.

Sequential grafting
The rationale for single SVG conduits per distal coronary anastomosis arose from the experience gained
during the 1970s. It was common to use a single length of SVG to commence at the aorta and then
graft all distal targets with sequential anastomoses - the so-called “round the world” graft. Since the
most common site of SVG graft failure was near to the aortic anastomosis, the danger was that all grafts
would fail simultaneously, leading to large ischemic implications. The strategy of a separate conduit for
each anastomosis was therefore a strategy of limiting the impact of SVG graft failure to just one target
anastomosis. Sequential grafting therefore fell out of favour.