Supraceliac Aorta Research Articles

Technique of hepatic arterial anastomosis in living donor pediatric auxiliary partial orthotopic liver transplantation

Technique of hepatic arterial anastomosis in living donor pediatric auxiliary partial orthotopic liver transplantation

A simplified experimental model of large-for-size liver transplantation in pigs

OBJECTIVE:The ideal ratio between liver graft mass and recipient body weight for liver transplantation in small infants is unknown; however, if this ratio is over 4%, a condition called large-for-size may occur. Experimental models of large-for-size liver transplants have not been described in the literature. In addition, orthotopic liver transplantation is marked by high morbidity and mortality rates in animals due to the clamping of the venous splanchnic system. Therefore, the objective of this study was to create a porcine model of large-for-size liver transplantation with clamping of the supraceliac aorta during the anhepatic phase as an alternative to venovenous bypass.METHOD:Fourteen pigs underwent liver transplantation with whole-liver grafts without venovenous bypass and were divided into two experimental groups: the control group, in which the weights of the donors were similar to the weights of the recipients; and the large-for-size group, in which the weights of the donors were nearly 2 times the weights of the recipients. Hemodynamic data, the results of serum biochemical analyses and histological examination of the transplanted livers were collected.RESULTS:The mortality rate in both groups was 16.5% (1/7). The animals in the large-for-size group had increased serum levels of potassium, sodium, aspartate aminotransferase and alanine aminotransferase after graft reperfusion. The histological analyses revealed that there were no significant differences between the groups.CONCLUSION:This transplant method is a feasible experimental model of large-for-size liver transplantation.

Flutamide fails to reduce resuscitation requirements in a porcine ischemia-reperfusion model

BackgroundHemorrhagic shock and subsequent resuscitation can lead to ischemia-reperfusion injury, followed by multiorgan failure and death. Flutamide, a vasoactive nonsteroidal antiandrogen compound, is thought to improve tissue and organ perfusion. We tested whether administration of flutamide-cyclodextrin (FLU-CYD) alters physiologic parameters or resuscitation requirements in a porcine model of severe acidosis and shock secondary to combined hemorrhage + ischemia-reperfusion injury. Methods and materialsFifteen male pigs underwent a 35% blood-volume hemorrhage. Ischemia was induced by cross-clamping the supraceliac aorta for 50 min followed by reperfusion and resuscitation. FLU-CYD complex was administered during aortic clamping. Fluid resuscitation and epinephrine were titrated by protocol to maintain mean arterial pressure ≥40 mm Hg for 6 h. Sequential laboratory results were obtained and serum levels of FLU and 2-hydroxy-flutamide (FLUOH) were measured by mass spectrometry. ResultsMean requirements for injured control swine were 14.6 (± 1.21 standard error of the mean [SEM]) L crystalloid saline and 0.59 (± 0.29 SEM) g epinephrine, compared with 16.30 (± 1.33 SEM) L and 0.54 (± 0.16 SEM) g, respectively, in the FLU-CYD group (both P > 0.05). There were no significant differences in central hemodynamics between control and experimental groups. No significant differences for pH, bicarbonate, fibrinogen, or international normalized ratio were evident. FLU-CYD resuscitation was associated with a significant increase in lactate levels compared with controls (10.1 versus 5.7 mmol/L, P < 0.05). Histologic injury was significantly increased in the livers of FLU-CYD compared with sham (P = 0.022). High serum levels of FLU and the active metabolite FLUOH were measurable throughout the resuscitation period. ConclusionsFlutamide failed to show any benefit to resuscitation in a model of severe injury and was associated with increased acidosis, hemodilution, and liver injury compared with standard crystalloid resuscitation.

In vivo validation of 4D flow MRI for assessing the hemodynamics of portal hypertension

AbstractPurpose:To implement and validate in vivo radial 4D flow MRI for quantification of blood flow in the hepatic arterial, portal venous, and splanchnic vasculature of healthy volunteers and patients with portal hypertension.Materials and Methods:Seventeen patients with portal hypertension and seven subjects with no liver disease were included in this Health Insurance Portability and Accountability Act (HIPAA)‐compliant and Institutional Review Board (IRB)‐approved study. Exams were conducted at 3T using a 32‐channel body coil with large volumetric coverage and 1.4 mm isotropic true spatial resolution. Using postprocessing software, cut‐planes orthogonal to vessels were used to quantify flow (L/min) in the hepatic and splanchnic vasculature.Results:Flow quantification was successful in all cases. Portal vein and supraceliac aorta flow demonstrated high variability among patients. Measurements were validated indirectly using internal consistency at three different locations within the portal vein (error = 4.2 ± 3.9%) and conservation of mass at the portal confluence (error = 5.9 ± 2.5%) and portal bifurcation (error = 5.8 ± 3.1%).Conclusion:This work demonstrates the feasibility of radial 4D flow MRI to quantify flow in the hepatic and splanchnic vasculature. Flow results agreed well with data reported in the literature, and conservation of mass provided indirect validation of flow quantification. Flow in patients with portal hypertensions demonstrated high variability, with patterns and magnitude consistent with the hyperdynamic state that commonly occurs in portal hypertension. J. Magn. Reson. Imaging 2013. © 2012 Wiley Periodicals, Inc.

In vivo validation of 4D flow MRI for assessing the hemodynamics of portal hypertension

To implement and validate in vivo radial 4D flow MRI for quantification of blood flow in the hepatic arterial, portal venous, and splanchnic vasculature of healthy volunteers and patients with portal hypertension. Seventeen patients with portal hypertension and seven subjects with no liver disease were included in this Health Insurance Portability and Accountability Act (HIPAA)-compliant and Institutional Review Board (IRB)-approved study. Exams were conducted at 3T using a 32-channel body coil with large volumetric coverage and 1.4 mm isotropic true spatial resolution. Using postprocessing software, cut-planes orthogonal to vessels were used to quantify flow (L/min) in the hepatic and splanchnic vasculature. Flow quantification was successful in all cases. Portal vein and supraceliac aorta flow demonstrated high variability among patients. Measurements were validated indirectly using internal consistency at three different locations within the portal vein (error = 4.2 ± 3.9%) and conservation of mass at the portal confluence (error = 5.9 ± 2.5%) and portal bifurcation (error = 5.8 ± 3.1%). This work demonstrates the feasibility of radial 4D flow MRI to quantify flow in the hepatic and splanchnic vasculature. Flow results agreed well with data reported in the literature, and conservation of mass provided indirect validation of flow quantification. Flow in patients with portal hypertensions demonstrated high variability, with patterns and magnitude consistent with the hyperdynamic state that commonly occurs in portal hypertension.

Long-Term Follow-Up of Aortohepatic Conduits in Pediatric Liver Transplantation

Introduction: Aortohepatic conduits are a vital option in liver transplantation and more commonly used in pediatric recipients. There is limited information on their long-term outcomes. This study is the largest series to date. Methods: We retrospectively reviewed all consecutive pediatric primary liver transplants performed between 1998 and 2009. Patient demographics, arterial reconstruction technique and the impact on morbidities and survival were studied. The results of aortohepatic conduits were compared with routine anastomosis (arterial revascularization by common hepatic or celiac artery of the recipient) performed in the same time period. Results: Aortohepatic conduits were required in 86/194 (44%) cases. Most common reasons were size (52%) and anatomical incongruities (16%). Grafts used were from the donor iliac arteries (78%), carotids (15%) and thoracic aorta (3%). Inflow was from the recipient infrarenal (95%) and supraceliac aorta (5%). Compared with Routine anastomosis group (N=108), patients with an aortohepatic conduit were younger (47% vs. 26% were < 12 months old, P=0.003), smaller (body weight was ≤6 kg in 27% vs. 10%, P=0.003), more likely to receive technical variant allografts (split/reduced liver or a live donor was used in 42% vs. 19%, P=0.001), and were more often hospital-bound before the transplant (51% vs. 35%, P=0.025). Postoperatively, Aortohepatic conduit group had a higher incidence of prolonged mechanical ventilation (19% vs. 7%, P=0.019) and small bowel obstruction (8% vs. 1%, P=0.023) compared with Routine anastomosis. No increased risk was observed for hepatic artery thrombosis (6% vs. 7%, P=0.66: all cases occurred within 1 month posttransplant), biliary complications (13% vs. 13%, P=0.97), and retransplants (8% vs. 14%, P=0.21). During a median follow-up of 82 months, Aortohepatic conduit group demonstrated a trend toward reduced overall patient survival rate at 5 years compared with Routine anastomosis (80% vs. 89%, respectively, P=0.068: Fig. A). Five-year graft survival was decreased in Aortohepatic conduit group (70% vs. 82%, P=0.047: Fig. B).[Figure]Causes of death and graft loss were similar between 2 groups. Subset analysis revealed that when an aortohepatic conduit was used, graft survival was comparable in recipients < 12 months of age or weighing ≤6 kg, but was diminished in those ≥12 months (65% vs. 84%, P=0.022) or >6 kg (69% vs. 84%, P=0.035). In contrast, graft survival was identical when patients were stratified by the type of the liver allograft (whole liver or technical variant) and pretransplant condition (home or hospital-bound). Conclusions: Aortohepatic conduits for children undergoing primary liver transplants provide a life-saving solution with excellent long-term arterial patency and survival, especially in high-risk recipients such as age < 12 months or body weight ≤6 kg.

Thoracic Aorta to Popliteal Artery Bypass for Bilateral Lower-Extremity Critical Limb Ischemia

Thoracic aortic to infrainguinal arterial bypasses are rare in the literature, even more so when the outflow is the popliteal artery bilaterally. The case of a patient presenting with critical limb ischemia, chronic infrarenal aortic occlusion, and recurrent thrombosis of a unilateral axillobifemoral graft managed with thoracoretroperitoneal bitransobturator bipopliteal bypass is presented. The patient's vascular history was significant for multiple previous groin procedures for thrombectomy of her axillobifemoral graft, aortomesenteric bypass, redo aortomesenteric bypass for graft thrombosis, and multiple bowel resection procedures for acute mesenteric ischemia. The thoracic aorta and popliteal arteries were selected as sites for proximal and distal anastomoses, respectively, given anticipated difficulty in exposing the supraceliac aorta and femoral arteries. The technique of this operative approach is discussed.

A fresh cadaver laboratory to conceptualize troublesome anatomic relationships in vascular surgery

Opportunities are declining for residents to participate in complex open vascular surgical operations. Open simulation using fresh cadavers potentially can be used to familiarize residents with complex vascular exposures. We evaluated the use of fresh cadavers to assist resident comprehension of complex anatomic relationships in vascular surgery. Twenty-two postgraduate year (PGY) 3 (n = 12) and PGY 4 (n = 10) general surgery residents attended five structured 4-hour cadaver skills laboratories. Residents performed five conceptually difficult and infrequently encountered operative vascular exposures: the supraclavicular subclavian and vertebral arteries, supraceliac aorta, superior mesenteric artery, proximal and distal renal arteries, and common iliac artery bifurcations. Residents were tested (oral board examination style with percentage correct of a predetermined checklist) in their knowledge and understanding of the anatomic relationships before and after the cadaver laboratories. Participants' self-reported confidence in performing these complex vascular exposures was also measured before and after the course using the operative confidence score (1 = not confident; 5 = highly confident) for each exposure. Participation in the course resulted in increases in participant comprehension and self-reported operative confidence in the supraclavicular subclavian and vertebral arteries, supraceliac aorta, superior mesenteric artery, renal arteries, and iliac bifurcation exposures. Before vs after the course, the mean oral examination scores were 5% vs 87%, 26% vs 94%, 19% vs 86%, 30% vs 88%, and 29% vs 87%, respectively (all P < .001), and mean operative confidence scores were 1.1 vs 2.9, 1.3 vs 3.5, 1.2 vs 3.2, 1.2 vs 3, and 1.5 vs 3.9, respectively (all P < 0.001). Fresh cadaver laboratories can provide a learner-centered and safe environment for acquiring procedural understanding and operative confidence of complex vascular exposures. This may allow for the transformational change essential to becoming a competent vascular surgeon.

Technique of Recanalization of Long-Segment Flush Superior Mesenteric Artery Occlusions

To describe technical tips for recanalization of long-segment flush superior mesenteric artery (SMA) occlusions. Ultrasound-guided left brachial artery access was gained in 2 patients with a 7F 90-cm sheath being advanced to the supraceliac aorta. The SMA stump was visualized using a selective inferior mesenteric artery (IMA) catheterization via femoral approach. A combination of a 7F 100-cm Multipurpose (MPA) guide and a 5F 125-cm MPA catheter was utilized to provide support for selective catheterization. Subsequently, a 0.018-inch wire and catheter were advanced crossing the area of occlusion. Predilatation was performed, followed by placement of covered stent. Both patients had uncomplicated course and resolution of symptoms. Flush SMA occlusions are challenging lesions but may be treated by antegrade percutaneous recanalization with good results. Technical aspects that facilitate recanalization include brachial approach, use of a stiff system (sheath, guide, and catheter) and concomitant injection to facilitate visualization of the SMA stump.

Hydrogen sulfide: improved hemodynamics and mitigation of ischemia-reperfusion injury in a large animal model (54.8)

Abstract Hemorrhagic shock can lead to ischemia-reperfusion (IR) injury followed by multi-organ failure and death. We tested intravenous Hydrogen sulfide (H2S) in a porcine hemorrhagic shock-resuscitation model evaluating IR injury. Experimental design: Sham (n=3); H2S untreated group (n=5); and H2S treated group (n=14). Animals were splenectomized, induced 35% hemorrhage and ischemia by cross-clamping the supraceliac aorta for 50 minutes. Intravenous fluid and H2S were administered at cross-clamp. Serial hemodynamic measurements and blood plasma analysis were followed for 6 h post-cross clamp release. The mean lactate levels (a measure of injury) were markedly lower in H2S group (7.0±1.6 mmol/L) compared to untreated group (9.3±1.2 mmol/L). Epinephrine requirement was significantly (P&amp;lt;0.05) lower in H2S group (727±645 µg) compared to untreated group (3052±1700 µg). Cardiac output was significantly (P&amp;lt;0.05) lower in H2S treated pigs. The intravenous fluid, hematocrit, and body temperature did not differ significantly (P&amp;lt;0.05). Blood plasma pro-inflammatory cytokines (IL1-β, IL-6, IFN-γ, TNF-α) at 6 h post-cross clamp release were significantly lower (P&amp;lt;0.05) compared to baseline in both H2S treated (n=4) and untreated groups (n=3). Organ (liver, kidney, heart, lung, small bowel, aorta) histopathology and gene expression (iNOS, eNOS, HO-1, HIF-1α, TNFα, IL-6, IFN-γ, IL1-β, etc.,) analyses are in progress. H2S improved hemodynamics and appears to be protective against IR injury.

Laparoscopic Release of the Median Arcuate Ligament for Celiac Artery Compression Syndrome in the Community Hospital Setting: A Case Report

Introduction: Celiac artery compression syndrome (CACS) is a rare disorder causing postprandial abdominal pain and weight loss secondary to mechanical compression of the celiac axis by an abnormally low insertion of the diaphragm at the median arcuate ligament (MAL). Historically, correction was performed through an upper midline laparotomy and release of the muscular fibers of the MAL causing celiac axis compression. Advanced laparoscopic techniques have been recently employed by some authors to confer the benefits of minimally invasive surgery to this patient population1–4 in the academic setting. We present a case of successful laparoscopic release of the MAL for CACS in the community hospital setting. Case: A 66-year-old man with longstanding history of postprandial abdominal pain and weight loss was referred for possible CACS. A mesenteric arteriogram was performed, which demonstrated a high-grade stenosis in the proximal celiac axis. The patient was prepared for a laparoscopic release of the MAL. A fellowship-trained minimally invasive/bariatric surgeon (T.S.D.) and a fellowship-trained vascular surgeon (W.K.) performed the operation. The patient was placed in the supine position with arms extended. A footboard was utilized to allow full reverse Trendelenburg position to be employed. Abdominal access was achieved using an Optiview approach through a left subcostal anterior axillary 12-mm incision. A 12-mm trocar was placed midway between the umbilicus and xyphoid process, two additional right upper quadrant ports were placed (5 mm, 12 mm), and a Nathanson liver retractor was placed through a 5-mm subxyphoid incision. The lesser sac was accessed by opening gastrocolic and gastrospenic attachments using an ultrasonic dissector. Both the left lobe of the liver and stomach were retracted anteriorly using the Nathanson retractor, allowing full view of the lesser sac and retroperitoneum. The left gastric, common hepatic, and splenic arteries were identified and traced back to the celiac trifurcation. The celiac axis was then circumferentially dissected and a vessel loop was applied. The area of compression was readily apparent upon gentle caudal retraction of the celiac artery. Monopolar hook electocautery was employed to carefully release the muscular attachments of the MAL that were causing arterial compression. The MAL was completely released when the supraceliac aorta was fully exposed from muscular diaphragmatic fibers. The patient did well postoperatively and was discharged home with an indwelling Foley catheter secondary to urinary retention and benign prostatic hypertrophy. Upon 2-week follow-up, the patient described full resolution of postprandial symptoms. Before surgery, the patient describes only tolerating full liquids, but at follow-up, is able to tolerate a regular solid diet for the first time in years. Conclusion: Laparoscopic release of the MAL for CACS is a technically demanding procedure with a high risk of open conversion and complications, even in the academic setting. However, with appropriately trained surgeons, this rare disorder can be treated in community hospital setting. No competing financial interests exist. Runtime of video: 5 mins 03 secs

Aortic Transection and Diverting Bypass as Treatment of Repetitive Recurrent Abdominal Aortic False Aneurysm Rupture in a Patient With Behcet’s Disease

Abdominal aortic false aneurysms in patients with Behcet's disease have been reported frequently and repaired successfully by various procedures; however, anastomotic false aneurysms have often been reported to occur after the operation. In this article, we report a case of four-time repetitive, recurrent suprarenal abdominal aortic false aneurysm ruptures that lasted for 7 years. The location of this aneurysm was not easy to repair not only by open surgical procedures but by endovascular stent because the aortic defect was too close to the visceral arterial branches. The last operation consisted of primary repair of aortic defect, transection of abdominal aorta at the level of supraceliac aorta with end closure, and a thoracic aorta to abdominal aorta bypass with Dacron graft. An 8-year follow-up revealed no more abdominal aortic aneurysm recurrence.

Thrombosed abdominal aortic aneurysm associated with an extensively “shaggy” aorta repaired anatomically via a thoracoabdominal approach with supraceliac aortic clamping: Report of a case

A 76-year-old man with a history of multiple laparotomies and severe coronary artery disease was referred to our hospital after the sudden development of pain and numbness in the lower extremities. Computed tomography showed a thrombosed abdominal aortic aneurysm and diffuse aortic atherosclerosis; compatible with a "shaggy aorta." A good response to thrombolytic therapy permitted elective scheduling of abdominal aortic surgery after coronary artery bypass grafting. We operated via an extended left retroperitoneal approach through a thoracoabdominal incision. Epiaortic ultrasonography revealed that only the supraceliac aorta was free of mobile thrombi and had minimal plaque; we therefore placed a proximal aortic cross-clamp there. Anatomic aortic reconstruction was then performed successfully using an aorto-biiliac graft to restore adequate distal blood flow. There were no vital-organ ischemic complications, and the postoperative course was satisfactory.

Endovascular aneurysm repair for ruptured abdominal aortic aneurysm: The Albany Vascular Group approach

Improvements in endovascular technology and techniques have allowed us to treat patients in ways we never thought possible. Today, endovascular treatment of ruptured abdominal aortic aneurysms is associated with markedly decreased morbidity and mortality compared with the open surgical approach, yet there are several fundamental obstacles in our ability to offer these endovascular techniques to most patients with ruptured aneurysms. This article will focus on the technical aspects of endovascular aneurysm repair for rupture, with particular attention to developing a standardized multidisciplinary approach that will help vascular surgeons deal with not just the technical aspects of these procedures but also address some of the challenges, including the availability of preoperative computed tomography, the choice of anesthesia, the percutaneous vs femoral cutdown approach, use of aortic occlusion balloons, need for bifurcated vs aortouniiliac stent grafts, need for adjunctive procedures, diagnosis and treatment of abdominal compartment syndrome, and conversion to open surgical repair.

Accessory hepatic artery: incidence and distribution

Background: Anatomic variations of the hepatic arteries are common. Preoperative identification of these variations is important to prevent inadvertent injury and potentially lethal complications during open and endovascular procedures. Objective: To evaluate the incidence, extra-hepatic course, and presence of side branches of accessory hepatic arteries, defined as an additional arterial supply to the liver in the presence of normal hepatic artery. Methods: Eighty-four human male cadavers were dissected using a transperitoneal midline laparotomy. The supra-celiac aorta, celiac axis, and hepatic arteries were dissected, and their trajectories were identified to describe arterial branching patterns. Results: Normal hepatic arterial anatomy was identified in 95% of the cadavers and six (5%) had accessory hepatic arteries. In five cadavers the accessory hepatic artery followed its course through the fissure for ligamentum venosum, and in one it coursed adjacent to the hepatic artery through the margin of the lesser omentum. One cadaver had a single side branch, which provided arterial blood supply to the left adrenal gland in the absence of any left inferior phrenic artery. Conclusion: Accessory hepatic artery most often follows the course of the hepatic fissure for ligamentum venosum. Albeit uncommonly found in 5% of cases, this finding should be identified during open and endovascular procedures to prevent inadvertent injury.

Open Surgical Treatment for Chronic Mesenteric Ischemia in the Endovascular Era: When It is Necessary and What is the Preferred Technique?

Treatment of chronic mesenteric ischemia has evolved during the last 2 decades. Endovascular treatment has first emerged as an alternative to bypass in the elderly or higher-risk patient, but has become the primary modality of treatment in most patients with suitable lesions, independent of their surgical risk. Open mesenteric revascularization with bypass or (rarely) endarterectomy still has an important role in the treatment of patients with more extensive disease, including long-segment or flush occlusions, small vessel size, multiple tandem lesions, and severe calcification. Our preference for open reconstruction in good-risk patients with multivessel disease is a supraceliac aorta to celiac and superior mesenteric artery (SMA) bypass, whereas an iliac artery to SMA bypass or, occasionally, an infrarenal aortic to SMA bypass is used in the higher-risk group. In this article, we summarize the selection criteria, techniques, and outcomes of open mesenteric reconstruction in the endovascular era.

Direct Anastomosis of the Donor Hepatic Artery to the Supraceliac Aorta without Extension Graft during Adult Liver Transplant in the Era of Extended Criteria Donors: Report of a Case

Arguably, one of the most challenging aspects of liver transplant surgery is the hepatic artery reconstruction. When the donor and recipient arteries are normal, this anastomosis can still be difficult. However, when the recipient artery has been dissected or is small other alternative reconstructions must be considered. Routinely, the donor surgery includes removing the iliac artery and vein specifically to aid in alternative reconstruction techniques. With the increase use of extended criteria donors (i.e., specifically age >55) the iliac vessel may be unusable because of atherosclerotic disease. This paper describes revisiting an alternative technique for hepatic artery reconstruction during cadaveric liver transplant when the recipient artery has been dissected and the iliac vessels were unusable secondary to arterial plaque from a 75 yo donor. Herein, we describe the successful anastomosis of the celiac artery with aortic patch from the donor directly to the supraceliac aorta of the adult recipient.

Hybrid Repair of Aortic Aneurysms Involving the Visceral and Renal Vessels

We sought to analyze our experience with hybrid treatment of aortic aneurysms involving the renal and visceral arteries. We conducted a retrospective review of 36 consecutive patients who underwent renal/visceral bypasses followed by aortic endografting. Patient demographics, medical history, operations, complications, graft patency, and patient survival were recorded. Observational and comparative analyses were performed. Mean patient age was 71 years. Mean aneurysm diameter was 6.3 cm (range 4.1-9.4 cm). Crawford aneurysm types included 1 type I, 10 type II, 12 type III, 10 type IV, and 3 pararenal aneurysms. Four patients were symptomatic. One hundred twenty-three bypasses were performed (median of three per patient), including 62 renal, 32 superior mesenteric, and 29 celiac arteries. Retrograde inflow (using the iliac arteries, aorta, or a limb of an aortobifemoral graft) was obtained in 30 patients and antegrade inflow was performed in six (three from the supraceliac aorta and three celiac branch to renal bypasses). In-hospital mortality occurred in 3 patients (8.3%). Patient survival was 80% at a mean follow-up of 6 months. Major morbidity occurred in 17 patients (47%) and included need for dialysis (5), ischemic colitis (3), failure to thrive (5), temporary paraparesis (1), and need for reoperation (7). No patient sustained permanent paraplegia. Mean length of stay was 26 days (range 8-100 days). Primary renovisceral bypass graft patency rate at 8 months was 93%. During follow-up, 14 patients developed at least one endoleak, 2 patients required percutaneous intervention, and the rest remained under observation. At last follow-up, four type 2 endoleaks and one type 3 endoleak with stable or decreasing aneurysm size. Hybrid repair of aortic aneurysms involving the renal and visceral arteries is feasible with a reasonable mortality and satisfactory short-term visceral graft patency rate. However, the morbidity of the debranching procedures is high. More stringent patient selection may improve these results.

Obstruction of the Celiac Axis Resulting in a Pancreaticoduodenal Artery Aneurysm

A 47-year-old woman complained of abdominal pain, and a computed tomography scan indicated compressive obstruction of the celiac axis and a 4-cm retropancreatic aneurysm. An angiogram identified the aneurysmal vessel as the posterior pancreaticoduodenal artery. All foregut structures were supplied by this aneurysmal vessel. Via an open approach, the inflow and outflow of the aneurysm were ligated, and blood flow to the celiac axis was reconstructed via a bypass from the supraceliac aorta. A follow-up scan indicated complete thrombosis of the aneurysm. The patient is now symptom free. Open reconstruction of the celiac axis is mandatory when ligation of a pancreaticoduodenal aneurysm results in foregut ischemia. Ligation and reconstruction can be done safely and effectively in the elective setting.

Prospective and Retrospective ECG Gating for Thoracic CT Angiography: A Comparative Study

The objective of our study was to compare radiation dose, contrast load, thoracic aortic attenuation value, and image quality parameters of MDCT thoracic aortography performed with prospective and retrospective cardiac gating. Studies were performed on 80 patients (prospective ECG gating, n = 40; retrospective ECG gating, n = 40) either being evaluated for thoracic aortic aneurysm (n = 23) or aortic dissection (n = 36) or undergoing postsurgical or postintervention follow-up (n = 21). Image acquisition parameters and radiation dose (CT dose index volume [CTDI(vol)] and dose-length product [DLP]) were obtained from image archival data. Contrast load and aortic attenuation values were obtained from a data registry. The comparative degrees of motion artifact and banding artifact were assessed on parasagittal maximum-intensity-projection (MIP) images and reformatted images in the plane of the aortic valve. CTDI(vol) and DLP in the prospective ECG-gating group was 28.8 +/- 2.12 mGy (mean +/- SD) and 833.7 +/- 115.77 mGy/cm, respectively, which are significantly lower (p < 0.001) than those values in the retrospective ECG-gating group (74.7 +/- 13.42 mGy and 2,547.3 +/- 553.27 mGy/cm). The average contrast load in the prospective gating group was 109.1 +/- 14.74 mL and in the retrospective gating group, 101.3 +/- 10.45 mL (p < 0.05). The average aortic attenuation values (in Hounsfield units) for the prospective and retrospective ECG-gated groups were 447.6 and 350.2 HU, respectively, for the mid ascending aorta, 413.6 and 325.7 HU for the mid aortic arch, 418.2 and 327.6 HU for the mid descending aorta, and 355.0 and 306.2 HU for the supraceliac aorta. Subjective scores of motion artifact and banding artifact were equivalent between the two groups. Compared with retrospective ECG-gated thoracic CT angiography, prospective ECG-gated thoracic CT angiography was associated with a lower radiation dose, slightly increased contrast load, increased aortic attenuation values, and equivalent image quality.