Hepatic Artery Reconstruction With Autologous Inferior Mesenteric Artery Graft in Living Donor Liver Transplant Recipients.

INTRODUCTION: In living donor liver transplantation (LDLT), hepatic arterial continuity is crucial to avoid biliary leakage, biliary stricture, cholangitis, and graft and patient loss. Sometimes there exist factors making anastomosis difficult or even impossible. In these cases, a vascular graft may be needed to bridge the two arteries for revascularization. METHOD: Medical records of 297 patients who underwent LDLT between June 2000 and July 2016 at the Hepatopancreatobiliary Surgery and Liver Transplantation Unit of Dokuz Eylul University Hospital were reviewed retrospectively. Twenty-eight (9%) patients younger than the age of 18 were excluded from the study. The remaining 269 patients were included in the study. We analyzed data of patients who developed hepatic arterial complications during or after LDLT and underwent revascularization using autologous interposed inferior mesenteric artery (IMA) grafts. RESULTS: In 8 (2.9%) of the 269 patients who underwent LDLT and were included in the study, autologous interposed IMA grafts were used for the hepatic artery revascularization. All of the patients were males. Their mean age was 42 (range, 25-57). The mean duration of follow-up was 83.25 months (range, 3-144 months). One patient developed intraoperative hepatic arterial thrombosis (HAT) after autologus IMA reconstruction and this patient needed retransplantation. No arterial complications developed in the other 7 patients. CONCLUSION: Autologous interposed IMA graft could be used as an alternative vascular graft in hepatic artery revascularization to provide tension-free hepatic arterial continuity.

Allogeneic anorectal transplantation in rats: technical considerations and preliminary results.

Fecal incontinence is a challenging condition with numerous available treatment modalities. Success rates vary across these modalities, and permanent colostomy is often indicated when they fail. For these cases, a novel potential therapeutic strategy is anorectal transplantation (ATx). We performed four isogeneic (Lewis-to-Lewis) and seven allogeneic (Wistar-to-Lewis) ATx procedures. The anorectum was retrieved with a vascular pedicle containing the aorta in continuity with the inferior mesenteric artery and portal vein in continuity with the inferior mesenteric vein. In the recipient, the native anorectal segment was removed and the graft was transplanted by end-to-side aorta-aorta and porto-cava anastomoses and end-to-end colorectal anastomosis. Recipients were sacrificed at the experimental endpoint on postoperative day 30. Surviving animals resumed normal body weight gain and clinical performance within 5 days of surgery. Isografts and 42.9% of allografts achieved normal clinical evolution up to the experimental endpoint. In 57.1% of allografts, signs of immunological rejection (abdominal distention, diarrhea, and anal mucosa inflammation) were observed three weeks after transplantation. Histology revealed moderate to severe rejection in allografts and no signs of rejection in isografts. We describe a feasible model of ATx in rats, which may allow further physiological and immunologic studies.

Comparative morphometric analysis of 5 interpositional arterial autograft options for adult living donor liver transplantation.

UNLABELLED: In living donor liver transplantation, the right-sided graft presents thin and short vessels, bringing forward a more difficult anastomosis. In these cases, an interpositional arterial autograft can be used to favor the performance of the arterial anastomosis, making the procedure easier and avoiding surgical complications. OBJECTIVE: We compared the inferior mesenteric artery (IMA), the splenic artery (SA), the inferior epigastric artery (IEA), the descending branch of the lateral circumflex femoral artery (LCFA), and the proper hepatic artery (PHA) as options for interpositional autograft in living donor liver transplantation. METHOD: Segments of at least 3 cm of all 5 arteries were harvested from 16 fresh adult cadavers from both genders through standardized dissection. The analyzed measures were proximal and distal diameter and length. The proximal diameter of the RHA and the distal diameter of the SA, IMA, IEA and the LCFA were compared to the distal diameter of the RHA. The proximal and distal diameters of the SA, IEA and LCFA were compared to study caliber gain of each artery. RESULTS: All arteries except the IMA showed statistical significant difference in relation to the RHA in terms of diameter. Regarding caliber gain, the arteries demonstrated statistical significant difference. All the harvested arteries except PHA were 3 cm in length. CONCLUSION: The IMA demonstrated the best compatibility with the RHA in terms of diameter and showed sufficient length to be employed as interpositional graft. The PHA, the SA, the IEA and the LCFA presented statistically significant different diameters when compared to the RHA. Among these vessels, only the PHA did not show sufficient mean length.

The fetal porcine aorta and mesenteric acellular matrix as small-caliber tissue engineering vessels and microvasculature scaffold.

BACKGROUND: The extracellular matrix (ECM) is characterized by not only well-preserved scaffolds of organs and vascularized tissues, but also by extremely low immunogenicity during allo- or xeno-implantation. This study aimed to establish a model of a composite microvasculature network scaffold with a small-caliber-dominant vascular pedicle by decellularizing fetal porcine aorta and the conterminous mesentery. METHODS: The aorta and the conterminous mesenteric vascular system originating from the inferior mesenteric artery were harvested from fetal pigs at late gestation. All of the cellular components were removed by sequential treatment with Triton X-100 and sodium dodecyl sulfate. After the degree of decellularization was assessed, the fetal porcine aorta and mesenteric acellular matrix (FPAMAM) were transplanted into dogs. RESULTS: Gross and histologic examination demonstrated the removal of cellular constituents with preservation of ECM architecture, including macrochannels and microchannels. The residual DNA content in the FPAMAM was less than 2 %. The aorta and microchannels were perfused well, and the fetal porcine aorta had good patency for more than 3 months. CONCLUSIONS: The integrity of the FPAMAM provided a scaffold for the reconstruction of a rich vascular network with numerous segmentally radiating branches. Decellularized fetal porcine vascular tissue might be a potential alternative for xenogeneic transplantation based on its optimized properties and low immunogenicity. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Rescue for rare complications of the hepatic artery in living donor liver transplantation using grafts of autologous inferior mesenteric artery.

This report describes two rescued cases with rare complications of the hepatic artery in living-donor liver transplantation (LDLT). In both cases a segment of the autologous inferior mesenteric artery (IMA) was successfully used as an arterial graft for re-vascularization under microsurgery. The first case was that of a pseudoaneurysm of the hepatic artery, which caused massive gastrointestinal bleeding. The hepatic arteries of the pre- and post-aneurysm were divided, and the arterial graft from the recipient's IMA was interposed for reconstruction. The second case was that of an intimal dissection of the recipient's hepatic artery. Because the dissection extended to the root of the common hepatic artery, the autologous IMA was interposed between the donor's hepatic artery and the proximal stump of the recipient's splenic artery. Reconstruction using the arterial graft of the autologous IMA is feasible for re-vascularization of the hepatic artery in liver transplantation.

Failed AAA endograft exclusion due to type II endoleak: explant analysis.

PURPOSE: To report the patient history and analysis of an explanted modular bifurcated endograft that was implanted to exclude an abdominal aortic aneurysm (AAA). CASE REPORT: An 80-year-old man with a 6-cm AAA underwent uneventful endovascular implantation of a bifurcated AneuRx stent-graft. His postprocedural clinical course was uneventful, although persistent contrast enhancement of the aneurysm remained via the inferior mesenteric artery (IMA). By 6 months, an endoleak connecting to the lumbar and mesenteric arteries became apparent. Over the ensuing 12 months, the endoleak and aneurysm enlarged; branch artery embolization was attempted in 4 percutaneous procedures. Despite successful IMA occlusion, the aneurysm continued to increase in diameter and volume, necessitating conversion to a conventional bypass at 20 months. Analysis of the explanted specimen revealed an intact endograft with fibrous incorporation of the stent framework at the proximal and distal fixation sites only; no incorporation of the endograft was noted within the aneurysm. The feeding channel for the endoleak was not identified. CONCLUSIONS: Serial imaging is a vital component of endograft surveillance, and persistent type II endoleaks that cannot be completely embolized endanger the longevity of the aneurysm exclusion. Explant analysis can play an important role in understanding the mechanisms of endograft failure.

Endovascular stent-graft in abdominal aortic aneurysms: the relationship between patent vessels that arise from the aneurysmal sac and early endoleak.

PURPOSE: To determine the association of patent sac branch vessels (lumbar and inferior mesenteric arteries [IMAs]) with early endoleak rate after stent-graft repair of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: Pre- and postoperative computed tomographic (CT) angiograms in 158 patients who underwent stent-graft AAA repair were retrospectively reviewed to determine the preoperative patency of IMAs and other sac branch vessels (feeders) and presence or absence of immediate postoperative endoleak. Relationships of early endoleak rate with total branch vessel, IMA, and lumbar artery patency and graft type were evaluated. RESULTS: There was a significant association between patency of sac feeders and rate of early endoleak, especially type 2. As total patent feeders increased from zero to three to four to six, total endoleak rate increased from 6% (one of 17) to 35% (30 of 86); type 2 endoleak rate, from 0% to 25%. IMA patency was significantly associated with total early endoleak rate. Increasing lumbar artery patency also was associated with significantly higher total and type 2 endoleak rates: With zero to three lumbar arteries, the total endoleak rate was 17% and type 2 endoleak rate was 13%, as compared with 60% and 50%, respectively, with more than six patent lumbar arteries. CONCLUSION: Sac branch vessel patency is associated with significantly higher early total and type 2 endoleak rates after stent-graft repair of AAAs; thus, patent sac branches play an important role in the pathogenesis of endoleaks.