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Page 10 of 17 Hong et al. Vessel Plus 2022;6:4 https://dx.doi.org/10.20517/2574-1209.2021.88

Figure 7. As indicated, the proximal anastomosis may be performed as completion of previous elephant trunk (A) and frozen elephant
trunk (B) repairs. The graft-to-graft anastomosis is readily performed and aids hemostasis. If needed, a strip of felt can provide
additional support to secure the anastomosis. The figure is used with the permission of Baylor College of Medicine.

After the primary suture line is completed, the graft is carefully examined for gaps, overlapping sutures, or
tears in the aorta. Felt-pledgeted mattress sutures are applied to ensure a secure anastomosis, given that
blood pressure targets are higher in the postoperative period. The cross-clamp initially placed proximal to
the left subclavian artery is then moved onto the graft to reestablish flow to the left subclavian and vertebral
arteries.

Visceral and renal perfusion
After the patient is weaned from LHB, the distal cannula and distal aortic cross-clamp are removed. This
portion of the aorta is then opened longitudinally [Figure 8]. The dissecting septum and thrombus are
removed, facilitating exposure of the entire aorta, including the intercostal, visceral, and lumbar branches.
Briskly back-bleeding intercostal or lumbar arteries are oversewn to avoid steal. Selective visceral perfusion
with isothermic, self-oxygenated blood is performed by using 9-French balloon-tipped catheters extending
from a Y-branch of the LHB and inserted into the celiac axis and SMA at a flow rate of 300-400 mL/min.
We protect the renal arteries with cold (4 °C) histidine-tryptophan-ketoglutarate perfusate (300 mL every 6-
12 min) delivered by using 9-French balloon-tipped catheters extending from a separate cooling circuit; the
patient’s temperature is carefully monitored to avoid overcooling. Alternatively, the LHB circuit can be used
to provide isothermic, self-oxygenated blood to all four branching arteries.

Reimplantation of intercostal or lumbar arteries
We identify 2 or 3 pairs of arteries feeding the spinal cord between T7 and L2 that are large and have
minimal or no back-bleeding. These are to be used for reimplantation with an island patch or an 8-mm
interposition Dacron graft. We typically use an island patch and a side-to-side anastomosis with 3-0
polypropylene sutures [Figure 9]. To reduce the risk for subsequent pseudoaneurysm formation, we
minimize the inclusion of the native aorta in the patch. Felt-pledgeted mattress sutures are liberally used for
reinforcement if the aortic tissue is fragile. The proximal aortic cross-clamp is then moved distally to the
island patch to perfuse the spinal cord through the intercostal or lumbar arterial patch.