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Page 14 of 22 Royse et al. Vessel Plus 2020;4:5 I http://dx.doi.org/10.20517/2574-1209.2019.34

In the era of arterial grafting, sequential grafting is essential to maximise the efficient use of conduit. The
underlying premise is that arterial conduits will remain patent in the long term, distinct from the SVG
experience.

A wide variety of sequential anastomosis techniques has been described [92-95] , but we describe a simple and
pragmatic approach in this section. The conduit is then draped over the coronary artery at whatever angle
appears to offer the best “lie” without tension. This may vary from directly overlying (“parallel”), to crossing
at right angles (“diamond”) or somewhere in between (“oblique”). An incision is made longitudinally
in both coronary artery and conduit of equal size. If the first suture placed passes through the native
coronary artery at a point where the heel of the conduit would lie, and the second needle is then used to
pass through the conduit at the heel, this angle is preserved. The anastomosis may then be completed with
whatever usual suture method is preferred by the surgeon.

Tips: Arterial conduits may be constructed with parallel or oblique anastomoses due to the ability of
the arterial conduit to adopt curves with redundant length of conduit as they are not prone to kinking.
However, the SVG is very prone to kinking and it is essential for most sequential anastomoses that it be
constructed to prevent any curvature to SVG, which usually results in the lie of the SVG and the coronary
target being at right angles to each other - the diamond anastomosis.

Tips: It is generally easier to construct sequential anastomoses along the length of the conduit from its
proximal to distal end, as this facilitates the movement of the free distal end of the conduit during suturing.
Consideration should be made to creating the aortic anastomosis first, followed by sequential grafting along
the length of the conduit as required.

Y (composite) grafting
The key elements of Y grafting are established by the techniques already described [95-99] . Use of RAY where
the LIMA and left RA are harvested simultaneously results in no prolongation of the operation over usual
practice and additionally may be useful if the right RA has been used to perform diagnostic coronary
angiography.

To perform the Y anastomosis, place two folded gauze over the distal ascending aorta after division of
the thymus. This stabilises the movement from the heart facilitating suturing. At the level of the inferior
aspect of the brachiocephalic vein, make a longitudinal incision on the chest wall aspect of the LIMA
approximately 50% longer than for the LAD anastomosis. The proximal end of the RA [or free right internal
mammary artery (RIMA)] is then sutured using the usual method of the surgeon. The two conduits should
be tacked together to prevent inadvertent torsion occurring.

The LAD territory should be grafted with the LIMA first, and sequential grafts performed to diagonal
arteries as appear comfortable by draping the LIMA over the branches. This sequence is necessary to
position the Y graft correctly, which should lie near to the lateral border of the pulmonary artery. If a hole
was made in the pericardium to pass the conduits, the Y should be positioned near to this hole. The RA (or
second IMA) should then be used to revascularize the circumflex and/or the right coronary territory by
performing sequential anastomoses along its length from proximal to distal. The final anastomosis for each
conduit is an end-to-side anastomosis.

If cardioplegic arrest is used, release of the conduit clamps may allow early reperfusion as well as optimal
conditions for inspection of the anastomoses for leaks and for the lie of conduits.

Tips: The complexity of this operation is usually exaggerated; however, caution is advised during the early
experience when using it for unstable patients, rescue situations or other factors that lead to additional