The orifice of the recipient right hepatic vein is maximally extended caudally or to the left on IVC to provide for optimal graft outflow. There are several ways to enlarge the orifice of RHV on recipient IVC. One is to elongate RHV orifice toward caudal side, in which RHV is incised caudally with a patch plasty of the recipient RHV to remove the acute angle between RHV and IVC under the side clamp of IVC beneath the RHV, which was proposed by Asan group Korea [6]. In another way, IVC is divided horizontally for a distance corresponding to the transverse dimension of the orifice in the graft [7, 8]. The cranial and caudal flaps are excised so that a large triangular or oval opening is created and matched with that of the graft [9]. This method, which can be done with either partial clamp or cross-clamp of IVC, seems most prevalent worldwide. In these methods, MHV + LHV is closed in the preparation of IVC. Our current way, which is supposed to provide the maximum orifice, is to extend the incision to connect RHV and MHV + LHV, which usually provides the orifice 5–6 cm in diameter [10]. As described above, this procedure is most facilitated by placing the cross-clamp on the suprahepatic vena cava as far cranial as possible. It is important to recognize that graft regeneration causes the right liver graft to rotate axially from right to left, which will result in a possible kinking of anastomosis or the compression of the anastomosis [11]. In this aspect, it is important to achieve an anastomosis with enough reservoir capacity to tolerate any kind of axial kink or compression by graft regeneration or surrounding tissues, for which making a large orifice on IVC to the possible extent is utmost important in recipient operation. For this purpose, we use cryopreserved homologous venous patch on the left wall of RHV to cover the widely opened anterior wall of recipient IVC as a roof-like reservoir [10, 11] (Fig. 12.3). In the presence of MHV (the extended right liver graft) or reconstructed MHV tributaries (the modified right liver graft), venoplasty between MHV and RHV is commonly undergone on bench surgery to create a common orifice with RHV permitting a single anastomosis to recipient IVC [3].

Unlike in right liver graft, outflow reconstruction in left liver is usually constructed between MHV + LHV on recipient IVC and the graft common orifice of MHV + LHV in end-to-end fashion [12]. However, it is also recommended as with the case in right liver to enlarge the orifice of the confluence of MHV and LHV in both the recipient IVC and the graft. First step is to unify LHV and MHV making an incision on the septum between MHV and LHV. Second, to enlarge the orifice further, the right wall of MHV is incised, and a venous patch is attached. The same patch procedure is usually needed in the graft [13, 14] (Fig. 12.4). This plasty of IVC can be accomplished with the partial clamping of IVC beneath the confluence of MHV + LHV; however, a larger orifice can be achieved by the same technique described in Sect. 12.2. We usually open recipient’s three hepatic veins continuously in left liver graft to achieve a maximal orifice on recipient IVC. When anastomosis is planned between thus widely opened anterior wall of IVC and the graft MHV + LHV which is generally short in height (2–5 mm), one certainly worries about tenting effect lifting the posterior wall of IVC upward resulting in a possible outflow block [15]. To avoid this phenomenon, a wall-like venous patch around MHV + LHV of the graft at the bench surgery to elongate the height and enlarge the orifice of MHV + LHV is mandatory [16].