Coeliac artery compression syndrome: the effect of decompression

Systematic Review of the Efficacy of Treatment for Median Arcuate Ligament Syndrome

OBJECTIVE

Since the first description of the median arcuate ligament syndrome (MALS), the existence for the syndrome and the efficacy of treatment for it have been questioned.

METHODS

A systematic review conforming to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement was conducted, with a broader view on treatment for MALS including any kind of coeliac artery release, coeliac plexus resection, and coeliac plexus blockage, irrespective of age. Online databases were used to identify papers published between 1963 and July 2021. The inclusion criteria were abdominal symptoms, proof of MALS on imaging, and articles reporting at least three patients. Primary outcomes were symptom relief and quality of life (QoL).

RESULTS

Thirty-eight studies describing 880 adult patients and six studies describing 195 paediatric patients were included. The majority of the adult studies reported symptom relief of more than 70% from three to 228 months after treatment. Two adult studies showed an improved QoL after treatment. Half of the paediatric studies reported symptom relief of more than 70% from six to 62 months after laparoscopic coeliac artery release, and four studies reported an improved QoL. Thirty-five (92%) adult studies and five (83%) paediatric studies scored a high or unclear risk of bias for the majority of the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) items. The meaning of coeliac plexus resection or blockage could not be substantiated.

CONCLUSION

This systematic review suggests a sustainable symptom relief of more than 70% after treatment for MALS in the majority of adult and paediatric studies; however, owing to the heterogeneity of the inclusion criteria and outcome parameters, the risk of bias was high and a formal meta-analysis could not be performed. To improve care for patients with MALS the next steps would be to deal with reporting standards, outcome definitions, and consensus descriptions of the intervention(s), after which an appropriate randomised controlled trial should be performed.

Long-term symptom improvement and health-related quality of life after operative management of median arcuate ligament syndrome

OBJECTIVE

To investigate long-term symptom improvement and health-related quality of life (HRQOL) after operative intervention for median arcuate ligament syndrome (MALS).

METHODS

Clinical data of all consecutive patients treated by operative management of MALS from 1999 to 2018 were reviewed. A cross-sectional questionnaire using the Visick score, the Gastrointestinal Quality of Life Index, and Short Form (SF)-12v2 questionnaires was performed to assess long-term outcomes. The SF-12 HRQOL domains were compared between symptom-free and symptomatic patient groups and to averages for the US general population. Treatment failure was defined as no relief after surgery and Visick category 3 to 4 symptoms. Freedom from symptoms was estimated at 5 years.

RESULTS

A total of 100 patients were treated for MALS (mean age, 38 ± 18 years; 75% female). Open surgical release was performed in 81 and laparoscopic release in 19 patients. The most common presenting symptom was abdominal pain in 99 patients with postprandial exacerbation in 85. There was no mortality. Major adverse events at 30 days had occurred in 21 patients (open 19, laparoscopic 2) including myocardial infarction (n = 1), pancreatitis (n = 2), respiratory failure (n = 4), estimated blood loss of more than 1 L (n = 8), and postoperative ileus (n = 8). One patient treated by laparoscopic release required conversion for an aortic injury, which was treated by primary repair and splenectomy. Forty-six patients responded to the questionnaire with a mean follow-up of 8 ± 4 years. Initial symptom resolution or improvement was reported by 38 patients (83%), whereas 8 patients (17%) reported treatment failure. Seven of the 38 patients (18%) with initial treatment success reported symptom recurrence. The estimated 5-year freedom from symptoms was 67 ± 7%. All SF-12 HRQOL domains were significantly lower and below the average population range in symptomatic patients compared with those who were symptom free, in which all domains were within the average population range. The Gastrointestinal Quality of Life Index scores were also significantly lower in symptomatic patients. Forty respondents (87%) reported that they would still undergo operative management if given the choice, including all respondents who reported symptom recurrence.

CONCLUSIONS

The operative management of MALS can be performed with a low rate of complications. Approximately two-thirds of respondents were free of symptoms 5 years after the procedure. Treatment success in symptom-free patients was associated with an improved HRQOL on par with the population average compared with symptomatic patients. The vast majority of respondents would opt to have the operation again if given a choice. However, patients should be well-informed about the possibility of failure to relieve symptoms and symptom recurrence.

Celiac axis compression syndrome: laparoscopic approach in a strange case of chronic abdominal pain in 71 years old man

Celiac Axis Compression Syndrome by the Median Arcuate Ligament is a very rare condition characterized by chronic postprandial abdominal pain (angina abdominis), nausea, vomiting, which occurs mostly in young patients. The main treatment is a surgical procedure that consists of the division of the arcuate ligament combined with the section of the close diaphragmatic crus and the excision of the celiac plexus. Actually laparoscopic management is feasible and safe.

Open and laparoscopic treatment of median arcuate ligament syndrome

BACKGROUND

Median arcuate ligament syndrome (MALS) is a syndrome associated with chronic abdominal pain and radiographic evidence of celiac artery compression. We compared the evidence for both open and laparoscopic treatment of patients with MALS.

METHODS

We reviewed the English-language literature between 1963 and 2012. Presenting symptoms, clinical improvement, operative details, and intraoperative and postoperative complications were noted.

RESULTS

A total of 400 patients underwent surgical (open and laparoscopic) treatment for MALS. Three hundred thirty-nine patients reported immediate postoperative symptom relief (85%). Late recurrence of symptoms was reported in 19 patients in the open group (6.8%) and seven patients in the laparoscopic group (5.7%). Eleven out of 121 patients (9.1%) in the laparoscopic group required open conversion secondary to bleeding.

CONCLUSIONS

The available evidence demonstrates that both laparoscopic and open ligament release, celiac ganglionectomy, and celiac artery revascularization may provide sustained symptom relief in the majority of patients diagnosed with MALS. The role of arterial revascularization following ligament release remains unclear. The rate of open conversion with the laparoscopic approach is high, but no perioperative deaths have been reported.

Median Arcuate Ligament Syndrome: A Nonvascular, Vascular Diagnosis

Median arcuate ligament syndrome (MALS) is often diagnosed when idiopathic, episodic abdominal pain is associated with dynamic compression of the proximal celiac artery by fibers of the median arcuate ligament. The character of the abdominal pain is often postprandial and associated with gradual weight loss from poor food intake, suggestive of chronic mesenteric ischemia. However, the pathognomonic imaging feature of dynamic, ostial celiac artery compression with expiration does not consistently predict clinical improvement from revascularization. Proposed but unproven pathophysiological mechanisms include neurogenic pain from compression of the splanchnic nerve plexus and intermittent ischemia from compression of the celiac artery. Alterations in blood flow and ganglion compression are both associated with delayed gastric emptying, another physiological correlate of the clinical syndrome. Published reports describe a variable response to revascularization and nerve plexus resection suggest a need for translational research to better characterize this poorly understood clinical entity. We illustrate the current gaps in our knowledge of MALS with the case of a 51-year-old woman with a 4-year history of chronic abdominal pain who responded to a combination of ganglion resection and celiac artery reconstruction.

Recurrent abdominal pain and weight loss in an adolescent: celiac artery compression syndrome

Celiac artery compression syndrome is a rare cause of abdominal pain and weight loss, likely caused by compression of the celiac artery or plexus by the median arcuate ligament. A case of celiac artery compression syndrome in a 17-year-old male patient with severe postprandial pain and weight loss is described. Imaging techniques such as computed tomography, angiography and Doppler ultrasound identified the abnormality, which was corrected by laparoscopic surgery.

Retroperitoneal endoscopic release in the management of celiac artery compression syndrome

INTRODUCTION

Celiac artery compression syndrome (CACS) can be treated successfully by division of the median arcuate ligament and celiac plexus fibers. The standard technique is the open approach by an upper midline or left subcostal incision. Only six single cases in which a laparoscopic transabdominal approach for CACS was used have been reported. We prospectively evaluated the feasibility of the endoscopic retroperitoneal approach for treatment of CACS.

METHODS

All patients with symptoms suggestive of CACS were evaluated using splanchnic duplex ultrasound scanning, gastric exercise tonometry (GET), and multiplane selective splanchnic angiography. The criteria for treatment were chronic abdominal symptoms, respiratory-dependent CA stenosis, and abnormal GET result. The release was performed by a retroperitoneal endoscopic approach. Anatomic success of the procedure was confirmed by angiography.

RESULTS

The endoscopic retroperitoneal approach was used to treat 46 patients with CACS. One patient (2%) required conversion to an open procedure due to suprarenal artery bleeding. Release was ended prematurely in one patient due to a pneumothorax resulting in loss of working space. A postoperative pneumothorax developed in two patients, of which one needed treatment. No other complications were observed. Postoperative angiography during inspiration and expiration showed normal vessel anatomy in 36 of 46 patients. Six of 10 patients with persisting intraluminal stenoses were treated endovascularly. Five of these were successful, which brings the primary-assisted anatomic patency for the total group to 89% (41 of 46 patients). Three patients are being observed, and endovascular treatment remains an option in case of insufficient improvement. On median follow-up of 20 months (range, 2-42 months) 41 patients were free of symptoms or showed significant improvement.

CONCLUSIONS

The endoscopic retroperitoneal approach for the release of the CA in CACS, with additional endovascular treatment of persistent stenosis, is feasible and effective. Short-term results were comparable with the open procedure.

Clinical Approach to Chronic Gastrointestinal Ischaemia: From 'Intestinal Angina' to the Spectrum of Chronic Splanchnic Disease

Stenotic disorders of the splanchnic arteries are not rare, and it is generally assumed that symptoms are rare in patients with a single splanchnic stenosis, and even in patients with multiple-vessel stenoses. Currently, only gastric exercise tonometry aids the diagnostic evaluation, as it indicates actual ischaemia. Patients with stenotic disorders without complaints are referred to as having chronic splanchnic disease (CSD) and those with ischaemic complaints as having chronic splanchnic syndrome (CSS). The classical presentation of CSS, including the triad postprandial pain, weight loss and upper abdominal bruit, is also known as 'intestinal angina'. From the experience of our multidisciplinary working team on gastrointestinal ischaemia in 110 patients with stenoses of at least one splanchnic artery, two different clinical patterns were observed. In our series approximately 60% of patients with single-vessel stenoses, including the coeliac artery compression syndrome, have CSS. They have fewer complications, very low mortality, but most can be successfully treated by stenting or surgical treatment. Patients with multivessel splanchnic stenoses have more classical ischaemic complaints. Progression to a bowel infarction was seen in 34%, and mortality was 21%, mostly from bowel or myocardial infarction. Treatment should be tailored based upon perioperative risk assessment and local vascular anatomy. This may consist of autologous arterial bypass of one or two vessels, preferably antegrade. stenting or a combination of both. This differentiation between single- and multivessel splanchnic disease has considerable consequences for optimal work-up and treatment.

Single vessel abdominal arterial disease

The long-standing discussion concerning the mere existence of single vessel abdominal artery disease can be closed: chronic gastrointestinal ischaemia (CGI) due to single vessel abdominal artery stenosis exists, can be treated successfully and in a safe manner. The most common causes of single vessel CGI are the coeliac artery compression syndrome (CACS) in younger patients, and atherosclerotic disease in elderly patients. The clinical symptoms of single vessel CGI patients are postprandial and exercise-related pain, weight loss, and an abdominal bruit. The current diagnostic approach in patients suspected of single vessel CGI is gastrointestinal tonometry combined with radiological visualisation of the abdominal arteries to define possible arterial stenosis. Especially in single vessel abdominal artery stenosis, gastrointestinal tonometry plays a pivotal role in establishing the diagnosis CGI. First-choice treatment of single vessel CGI remains surgical revascularisation, especially in CACS. In elderly or selected patients endovascular stent placement therapy is an acceptable option.

Definitive Test to Diagnose Median Arcuate Ligament Syndrome: Injection of Vasodilator During Angiography

The diagnosis of median arcuate ligament (MAL) syndrome and its correlation with symptoms has been controversial since the disease entity was described. The authors describe a technique that will identify patients who will benefit from intervention. Eight patients with isolated celiac artery compression from MAL were identified by the authors. Their technique involved selective cannulation of the superior mesenteric artery (SMA) and injection of a vasodilator during angiography. Symptom reproduction and loss of collateral filling of the celiac territory represented a positive test: 4 of the 8 patients had a positive test and underwent successful surgical treatment of the condition; 3 of them remained asymptomatic at follow-up; 1 patient continues to have mild abdominal discomfort. Of the 4 patients with a negative test, 2 were found to have other conditions causing their symptoms. Vasodilator injection into the SMA is a useful diagnostic test to identify patients with symptomatic MAL syndrome.

Median arcuate ligament syndrome--a novel treatment using an intrathecal morphine pump to relieve intractable visceral pain

PURPOSE

Median arcuate ligament syndrome, which presents with intractable visceral pain, is difficult to both diagnose and treat. This case report describes the first use of an intrathecal morphine pump as an effective therapeutic intervention.

CLINICAL FEATURES

We describe a 39-year-old female who presented with a four-year history of misdiagnosed debilitating abdominal pain. After multiple failed attempts at medical management and surgeries, a trial of intrathecal narcotics provided significant relief. Six months after insertion of an intrathecal morphine pump, the patient was pain-free and had resumed all activities of daily living.

CONCLUSION

The use of an intrathecal narcotic pump should be considered for treatment of patients with intractable visceral pain secondary to median arcuate ligament syndrome.

Clinical anatomy of celiac artery compression syndrome: a review

Anatomic variations are often responsible for a variety of clinical conditions. In this review we investigate compression of the celiac artery and the superior mesenteric artery by the median arcuate ligament (MAL), diaphragmatic crura, or the celiac nerve plexus. This clinical condition known as celiac artery compression syndrome (CACS) has proven controversial in definition and relevance. This condition was first described as chronic abdominal pain because of the mesenteric ischemia caused by extrinsic compression of the celiac artery. Dunbar and others presented surgical approaches to decompress the celiac artery by releasing the MAL. Definitive answers have been sought to classify and relieve the clinical symptoms patients experience postprandially. Persistent symptoms following surgical treatment for CACS have led investigators to question the existence of this disease. Advances in technology such as angiographic MRI and color duplex ultrasonography have refreshed the importance of considering compression of the celiac artery during differential diagnoses. Because of the varying anatomic etiologies of disease, it is not possible to pinpoint a single cause for CACS. Potential etiologies for compression of the celiac artery include a "high take off" origin of the celiac artery compressed by normal diaphragmatic crura and MAL, a normal origin of the celiac artery with long diaphragmatic crura and MAL, large bilaterally fused celiac ganglia (with or without the involvement of the superior mesenteric ganglia) compressing the celiac trunk, celiacomesenteric trunk compression by diaphragmatic crura and MAL, or combinations of the above mentioned entities. In this review we describe potential sources of compression of the celiac artery by regional structures and treatments of CACS in an effort to justify the relevance of CACS in modern medicine.

Celiac trunk compression syndrome requiring surgery in 3 adolescent patients

BACKGROUND/METHODS

Celiac trunk compression syndrome is a rare cause of recurrent, nonspecific upper abdominal pain. In this article, we present 3 cases of celiac trunk compression syndrome in 15- and 16-year-old adolescents who were treated surgically in our clinic and discuss our findings with existing literature.

RESULTS

All 3 adolescents complained about unspecific upper gastrointestinal pain. The performance of digital subtraction angiography and, accordingly, magnetic resonance angiography showed, respectively, a stenosis and an occlusion of the celiac artery. In all cases, a decompression of the celiac trunk as well as a resection of the celiac plexus in the region near the outlet of the trunk was performed. Patients have been surveyed between 12 and 18 months postoperatively. In all cases, the gastrointestinal symptoms have completely disappeared.

DISCUSSION

Celiac artery compression syndrome is understood to consist of symptoms of recurrent pain, caused by a neurovascular narrowing of the aortic hiatus and celiac trunk. The surgical approach of choice is sharp transection of the median arcuate ligament, along with complete resection of the nerve fibers of the celiac plexus with or without performance of revascularisation. In summary, celiac trunk compression syndrome is a rare cause of recurrent epigastric pain that should be not be ignored completely as a differential diagnosis.

Clinical significance of splanchnic artery stenosis

BACKGROUND

The clinical relevance of splanchnic artery stenosis is often unclear. Gastric exercise tonometry enables the identification of patients with actual gastrointestinal ischaemia. A large group of patients with splanchnic artery stenosis was studied using standard investigations, including tonometry.

METHODS

Patients referred with possible intestinal ischaemia were analysed prospectively, using duplex imaging, conventional abdominal angiography and tonometry. All results were discussed within a multidisciplinary team.

RESULTS

Splanchnic stenoses were found in 157 (49.7 percent) of 316 patients; 95 patients (60.5 percent) had one-vessel, 54 (34.4 percent) two-vessel and eight (5.1 percent) had three-vessel disease. Chronic splanchnic syndrome was diagnosed in 107 patients (68.2 percent), 54 (57 percent) with single-vessel, 45 (83 percent) with two-vessel and all eight with three-vessel stenoses. Treatment was undertaken in 95 patients, 62 by surgery and 33 by endovascular techniques. After a median follow-up of 43 months, 84 percent of patients were symptom free.

CONCLUSION

Gastric exercise tonometry proved crucial in the evaluation of possible intestinal ischaemia. Comparing patients with single- and multiple-vessel stenoses, there were significant differences in clinical presentation and mortality rates.

Gastric exercise tonometry: the key investigation in patients with suspected celiac artery compression syndrome

INTRODUCTION

Controversy continues about the mere existence of the celiac artery compression syndrome. Earlier results of treatment of unselected patients groups showed varying, mostly disappointing, results. The recently introduced gastric exercise tonometry test is able to identify patients with actual gastrointestinal ischemia. We prospectively studied the use of gastric exercise tonometry as a key criterion for revascularization treatment in patients with otherwise unexplained abdominal complaints and significant stenosis of the celiac artery by compression of the arcuate ligament.

METHODS

Patients were prospectively selected using abdominal artery angiography and gastric exercise tonometry. Patients with a significant compression of the celiac artery, typical abdominal complaints, and abnormal tonometry were considered for revascularization.

RESULTS

Over a 7-year period, 43 patients with significant celiac artery compression were included in this study, and 30 patients were diagnosed as ischemic. Twenty-nine patients had revascularization, 22 (76 %) had a trunk release only. After a median follow-up of 39 months, 83% of patients were free of symptoms. The repeated tonometry after treatment improved in 100% of patients free of symptoms, compared with 25% in patients with persistent complaints after revascularization.

CONCLUSIONS

The results of this study suggest that the celiac axis compression syndrome exists and that the actual ischemia can be detected by gastric exercise tonometry and treated safely, with success.

Celiac artery compression syndrome in children, adolescents, and young adults: clinical and color duplex sonographic features in a series of 59 cases

OBJECTIVE

Abdominal pain is one of the most common conditions in childhood and adolescence. Celiac artery compression syndrome (CACS) is rarely suspected in this population. We present clinical and sonographic features from a series of 59 patients with this disorder.

METHODS

A total of 3449 patients from 0 to 18 years were investigated with 7639 abdominal color duplex sonographic examinations. Celiac artery flow velocity was measured at the branching off from the aorta in inspiration, expiration, and in between. Diagnosis of CACS was made if a greater than 2-fold acceleration of peak systolic flow in the celiac artery compared to the abdominal aorta or a peak systolic velocity greater than 200 cm/s was measured in the mid position and if a variation of flow velocity occurred during respiration. In 22 cases, angiography (21 magnetic resonance angiography and 1 digital subtraction angiography) was used to prove sonographic diagnosis.

RESULTS

Fifty-nine patients (among them 81% female) from 22 months to 19 years (clustering between 14 and 17 years) fulfilling color Doppler sonographic criteria of CACS were found, for a prevalence of 1.7%. Their symptoms included, among others, abdominal pain (71%), nausea (29%), thoracic pain (22%), heartburn (17%), weight loss (15%), vomiting (15%), systolic murmur (15%), postprandial accentuation of symptoms (15%), diarrhea (14%), respiratory discomfort (14%), and syncope (12%).

CONCLUSIONS

Celiac artery compression syndrome is more prevalent than expected, and conditions not usually connected to the disease were found. Alertness to CACS is recommended, especially in patients with a combination of characteristic symptoms. Color Doppler sonography is the modality of choice for diagnosing CACS.

Arcuate ligament vascular compression syndrome in infants and children

BACKGROUND

Arcuate ligament vascular compression syndrome has not been described previously in the pediatric or pediatric surgical literature. However, it is mentioned in the literature of vascular and general surgery and in journals of radiology and orthopedics. In this review, the intraoperative pathological anatomy and the principles of treatment for 8 children will be presented.

METHODS

The chart records and the anatomical sketches that were documented by the surgeon immediately after each procedure were analyzed retrospectively. In addition, preoperative courses and long-term follow-up (range, 3-18 years) were evaluated by a defined program.

RESULTS

The diagnosis of celiac artery compression by an arcuate ligament was suspected in children presenting with a history of several years of recurrent acute abdominal pain associated with a typical arterial bruit in the midline of the epigastric region.

CONCLUSIONS

Other diseases with recurrent abdominal pain and an arterial bruit must be excluded before making the decision for an operative intervention. Duplex ultrasound and angiography are possibly helpful tools to establish the respective diagnosis, but in the patients of the present series, these techniques neither confirmed compression of the celiac axis nor demonstrated decreased perfusion of the superior mesenteric artery. However, as the clinical symptoms clearly announce the disease, these diagnostic measures are not mandatory.

Clinical impact of gastric exercise tonometry on diagnosis and management of chronic gastrointestinal ischemia

BACKGROUND & AIMS

Chronic gastrointestinal ischemia or chronic splanchnic syndrome is a difficult diagnosis. The use of a physiologic test, combined with clinical and anatomic data, should improve diagnostic accuracy. This study evaluates the diagnostic accuracy and clinical impact of gastric tonometry during exercise (GET) in a patient cohort suspected of chronic splanchnic syndrome.

METHODS

From 1997 to 2000, 102 patients with chronic abdominal pain were analyzed. The workup included GET and selective biplane angiography. The diagnosis of gastrointestinal ischemia was based on consensus in a multidisciplinary working group and sustained on follow-up.

RESULTS

Gastrointestinal ischemia was diagnosed in 38 patients. In 33 patients chronic splanchnic syndrome was found, with single vessel involvement in 20 (17 celiac artery, 3 mesenteric superior) and multivessel disease in 13. In 5 patients nonocclusive ischemia was found. By using receiver operator curve analysis, the difference between gastric and arterial partial pressure of carbon dioxide (PCO2 gradient) proved to be the best GET parameter. The criteria for diagnosing ischemia in GET were Pco2 gradient > 0.8 kPa and increase gastric PCO2, with base excess decrease <8 mmol/L during exercise. GET had 78% sensitivity and 92% specificity. Twenty-five patients underwent vascular treatment (19 operative, 6 stent/percutaneous transluminal angioplasty). After 4 years of follow-up 83% of patients were alive and free of symptoms.

CONCLUSIONS

GET is an accurate diagnostic tool to show gastrointestinal ischemia. Including GET into clinical decision making enabled selecting patients with ischemia, who benefited from vascular and medical treatment. These benefits were sustained during 4-year follow-up. GET should be considered in the workup of patients with a suspected diagnosis, of gastrointestinal ischemia.

Chronic splanchnic ischaemia

Chronic splanchnic ischaemia is a relatively unusual clinical entity consisting of pain and/or weight loss and caused by chronic splanchnic disease (i.e. stenosis and/or occlusion of the coeliac and superior mesenteric artery). The occlusive disease is usually caused by atherosclerosis and is in itself not rare in older individuals. Extensive collateral circulation can develop between the three splanchnic arteries and may compensate for the decreased splanchnic perfusion over time. The pathophysiology of chronic splanchnic ischaemia has still not been completely elucidated.A reliable diagnosis of chronic splanchnic ischaemia, based on a proven causal relationship between the occlusive disease and the symptoms, can be very difficult. Traditionally, tests for evaluating the haemodynamic consequences of the vascular stenoses were not available. Important improvements in establishing a more reliable diagnosis have been achieved with duplex ultrasound and magnetic resonance evaluation of the splanchnic circulation. Tonometry is another promising functional test that may prove useful not only for gaining greater insight into the pathophysiology of chronic splanchnic ischaemia but also for the clinical evaluation of this syndrome. The natural history of chronic splanchnic disease suggests that progressive disease may result in acute mesenteric ischaemia. Surgical reconstruction of the coeliac and/or the superior mesenteric artery is the therapeutic standard with excellent short and long-term results. Satisfactory early results using angioplasty with or without stent suggest that this type of intervention may relieve symptoms in selected patients with a higher surgical risk.

Celiac artery compression syndromes

Compression of the visceral arteries can produce true mesenteric ischemia, but the syndrome is rare. The syndrome is caused by unfavorable anatomic relationships at the aortic hiatus among the CA, the SMA, and overlying structures, particularly the diaphragmatic crura. These anatomic relationships, in contrast to the syndrome they sometimes produce, are relatively common, which makes the detection of CA compression only a prerequisite to the diagnosis of the clinical entity. The diagnosis of CA compression syndrome ultimately depends on the relentless elimination of other possible causes for abdominal pain and on the knowledge that this curious syndrome does indeed exist. If properly diagnosed, the CA compression syndrome can be corrected with a safe, relatively simple surgical procedure. Past treatment series reflect too little appreciation for the extensiveness of a true, chronic CA injury. Revascularization of the CA, in addition to release of compression, should therefore be performed with greater frequency in the future. The young patients who are successfully diagnosed and treated for this unusual syndrome are frequently entirely relieved of long-standing, debilitating pain, and, like other patients with chronic mesenteric ischemia, they typically enjoy dramatic improvement in the quality of their lives. Thus, with the prospect of these patients in mind, a clinician should accept the opinion that the syndrome "does not exist" only after careful consideration of the entire literature.

Median arcuate ligament compression syndrome in monozygotic twins

Twin 27-year-old women had symptomatic mesenteric ischemia caused by median arcuate ligament compression. Arteriography demonstrated severe celiac artery stenosis in one twin, celiac artery occlusion in the other, and proximal superior mesenteric artery narrowing with retrograde filling from a meandering mesenteric artery in both. Division of the ligament and direct celiac artery revascularization completely relieved symptoms in both patients. Median arcuate ligament compression of the celiac and superior mesenteric arteries can result in mesenteric ischemia. Documentation of this unusual syndrome in monozygotic twins suggests that the responsible anatomic relationships are congenital.