Editorial comment: The right coronary artery: which graft and how to use it?

right mammary through the transverse sinus to the first marginal. For the right coronary system, we used the gastroepiploic artery targeted to the PDA. Today, because of the off-pump technique, we perform a lot of Y composite grafting with two mammaries. It all depends on the location of the marginal that we have to graft on the lateral wall of the heart. So, for example, if we have to graft only one proximal marginal artery, we will use two mammaries in an in situ configuration and the gastroepiploic artery targeted to the PDA. If there are several marginals to graft on the lateral wall of the heart, then we prefer to use a Y graft configuration with two mammaries, and if, only if, the right coronary artery is very stenosed, then we will complete the CABG with the right mammary on the PLA or PDA. We will do exactly the same with the gastroepiploic artery. We have clearly demonstrated that with the gastroepiploic artery as well as the right mammary used in a Y graft configuration, when targeted to the right coronary system, if you want to have a functional graft, and I mean by functional, an antegrade flow through the graft, you have to have a very narrowed right coronary artery. In order to evaluate the severity of the RCA, we prefer to use the MLD, minimum lumen diameter, rather than percentage of stenosis, because I think that the percentage of stenosis is clearly not a good tool to evaluate the severity of the lesion. But if you have an MLD of less than 0.7 mm, then, yes, we will use an arterial graft targeted to the RCA. If the MLD is above 1 mm, then we will use a saphenous vein graft. So today, you are completely right, we will prefer to use a vein if the lesion is, let's say, moderate to 70–80%—and once again I don't like to speak in terms of per cent of stenosis, I think that it is not a good tool to evaluate severity of the stenosis—and if it is above 80%, then, yes, we will use an artery. Dr D. Taggart (Oxford, UK): Let me ask the audience before we come to the gastroepiploic. If you use a second mammary artery routinely, and let's define routinely by over 50%, how many in the audience use a second mammary artery in 50% …