Dynamic ultrasonography for optimizing treatment position in superior mesenteric artery syndrome:Two case reports and review of literature

BACKGROUND Superior mesenteric artery(SMA)syndrome is a rare cause of duodenal obstruction by extrinsic compression between the SMA and the aorta(SMA-Ao).Although the left lateral recumbent position is considered effective in the treatment of SMA syndrome,individual variations in the optimal patient position have been noted.In this report,we present two elderly cases of SMA syndrome that exhibited rapid recovery due to ultrasonographic dynamic evaluation of the optimal position for each patient.CASE SUMMARY Case 1:A 90-year-old man with nausea and vomiting.Following diagnosis of SMA syndrome by computed tomography(CT),ultrasonography(US)revealed the SMA-Ao distance in the supine position(4 mm),which slightly improved in the lateral position(5.7–7.0 mm)without the passage of duodenal contents.However,in the sitting position,the SMA-Ao distance was increased to 15 mm accompanied by improved content passage.Additionally,US indicated enhanced passage upon abdominal massage on the right side.By day 2,the patient could eat comfortably with the optimal position and massage.Case 2:An 87-year-old woman with vomiting.After the diagnosis of SMA syndrome and aspiration pneumonia by CT,dynamic US confirmed the optimal position(SMA-Ao distance was improved to 7 mm in forward-bent position,whereas it remained at 5 mm in the supine position).By day 7 when her pneumonia recovered,she could eat with the optimal position.CONCLUSION The optimal position for SMA syndrome varies among individuals.Dynamic US appears to be a valuable tool in improving patient outcomes.

Emergency rescue of a patient with hemorrhagic shock caused by superior mesenteric artery rupture:A case report

BACKGROUND Superior mesenteric artery(SMA)injuries rarely occur during blunt abdominal injuries,with an incidence of<1%.The clinical manifestations mainly include abdominal hemorrhage and peritoneal irritation,which progress rapidly and are easily misdiagnosed.Quick and accurate diagnosis and timely effective treatment are greatly significant in managing emergent cases.This report describes emergency rescue by a multidisciplinary team of a patient with hemorrhagic shock caused by SMA rupture.CASE SUMMARY A 55-year-old man with hemorrhagic shock presented with SMA rupture.On admission,he showed extremely unstable vital signs and was unconscious with a laceration on his head,heart rate of 143 beats/min,shallow and fast breathing(frequency>35 beats/min),and blood pressure as low as 20/10 mmHg(1 mmHg=0.133 kPa).Computed tomography revealed abdominal and pelvic hematocele effusion,suggesting active bleeding.The patient was suspected of partial rupture of the distal SMA branch.The patient underwent emergency mesenteric artery ligation,scalp suture,and liver laceration closure.In view of conditions with acute onset,rapid progression,and high bleeding volume,key points of nursing were conducted,including activating emergency protocol,opening of the green channel,and arranging relevant examinations with various medical staff for quick diagnosis.The seamless collaboration of the multidisciplinary team helped shorten the preoperative preparation time.Emergency laparotomy exploration and mesenteric artery ligation were performed to mitigate hemorrhagic shock while establishing efficient venous accesses and closely monitoring the patient’s condition to ensure hemodynamic stability.Strict measures were taken to avoid intraoperative hypothermia and infection.CONCLUSION After 3.5 h of emergency rescue and medical care,bleeding was successfully controlled,and the patient’s condition was stabilized.Subsequently,the patient was transferred to the intensive care unit for continuous monitoring and treatment.On the sixth day,the patient was weaned off the ventilator,extubated,and relocated to a specialized ward.Through diligent medical intervention and attentive nursing,the patient made a full recovery and was discharged on day 22.The follow-up visit confirmed the patient’s successful recovery.

Isolated superior mesenteric artery dissection:An updated review of the literature

Isolated superior mesenteric artery dissection(ISMAD)is a rare but potentially life-threatening cause of acute abdominal pain.Owing to the availability of computed tomography angiography,more cases have been detected during screening for acute abdomen in recent years.With increasing knowledge of ISMAD,a better management strategy is being developed.To enhance our understanding and improve treatment outcomes of ISMAD,a systematic literature review was conducted with a focus on diagnosis and management strategies based on existing evidence.

How to deal with right hepatic artery coming from the superior mesenteric artery during minimally invasive pancreaticoduodenectomy: A systematic review

Background: Anatomical variations in the liver arterial supply are quite common and can affect the surgical strategy when performing a minimally invasive pancreaticoduodenectomy(MIPD). Their presence must be preemptively detected to avoid postoperative liver and biliary complications. Data sources: Following the PRISMA guidelines and the Cochrane protocol we conducted a systematic review on the management of an accessory or replaced right hepatic artery(RHA) arising from the superior mesenteric artery when performing an MIPD. Results: Five studies involving 118 patients were included. The most common reported management of the aberrant RHA was conservative(97.0%);however, patients undergoing aberrant RHA division without reconstruction did not develop liver or biliary complications. No differences in postoperative morbidity or long-term oncological related overall survival were reported in all the included studies when comparing MIPD in patients with standard anatomy to those with aberrant RHA. Conclusions: MIPD in patients with aberrant RHA is feasible without increase in morbidity and mortality. As preoperative strategy is crucial, we suggested planning an MIPD with an anomalous RHA focusing on preoperative vascular aberrancy assessment and different strategies to reduce the risk of liver ischemia.

Superior Mesenteric Artery Syndrome, a Rare Complication of Severe Malnutrition: Two Cases from a Subsaharian Endocrinology Department

Introduction: Superior mesenteric artery syndrome (SMAS), a rare diagnosis due to compression of the third duodenum between the superior mesenteric artery (SMA) and the aorta resulting in bowel obstruction, may lead to severe malnutrition. We report two cases of patients hospitalised in the Internal Medicine, Endocrinology, Diabetology, and Nutrition Department of the National Hospital Center (NHC) of Pikine. Observations: Patient 1: A 35-year-old female was referred for an aetiological diagnosis due to a rapid weight loss of 15 kilograms in one month, accompanied by persistent vomiting, following an appendectomy performed a month before admission. Upon clinical examination, she presented severe malnutrition (Buzby index of 76%), early post-prandial chronic vomiting, and a poor general condition. An abdominal CT scan revealed aortomesenteric clamp syndrome (AMCS) with an angulation between the aorta and the SMA of 13˚. The underlying cause in this patient was severe malnutrition. Fortunately, her condition improved with medical treatment. Patient 2: We report the case of a 30-year-old female hospitalized due to unusual weight-bearing post-prandial epigastric pain and intermittent vomiting over the past six months. Upon physical examination at admission, she exhibited severe malnutrition with a body mass index (BMI) of 14 kg/m2, a Buzby index of 71%, trophic disorders, and a stage IV general condition assessment according to the World Health Organization (WHO). An abdominal CT scan revealed AMCS with an angle between the aorta and the SMA of 22˚ and an aortomesenteric space of 4 mm. The outcome was poor with medical treatment failure and, unfortunately, the patient died before surgery. Conclusion: SMAS is rarely evoked in clinical practice despite the presence of contributing factors and suggestive clinical signs. The prognosis depends on management time.

The ratio of superior mesenteric artery diameter to superior mesenteric vein diameter based on non-enhanced computed tomography in the early diagnosis of spontaneous isolated superior mesenteric artery dissection

BACKGROUND:Spontaneous isolated superior mesenteric artery(SMA)dissection(SISMAD)is a rare cause of abdominal pain.The aim of the study is to investigate the role of a new parameter,the ratio of the SMA diameter to the superior mesenteric vein(SMV)diameter(SMA/SMV)based on non-enhanced computed tomography(CT),in the early diagnosis of SISMAD.METHODS:In a registry study from December 2013 to June 2021,97 abdominal pain SISMAD patients(SISMAD group)admitted to our hospital were enrolled.Meanwhile,the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control group.Student’s t-test,Wilcoxon rank-sum test,and Chi-square test were used to compare differences between the SISMAD and control groups.Med Calc was used to generate receiver operating characteristic(ROC)curve.RESULTS:A total of 291 abdominal pain patients,including 97 SISMAD patients and 194 nonSISMAD patients,were included in the current study.The maximum SMA diameter,perivascular exudation,and SMA/SMV based on non-enhanced CT were significant between the two groups(all P<0.05).ROC curves showed that for the maximum SMA diameter,the area under the curve(AUC),cut-off,sensitivity,and specificity were 0.926,9.80,93.8%,and 79.4%,respectively.For SMA/SMV,its AUC,cut-off,sensitivity,and specificity were 0.956,0.83,88.7%,and 92.3%,respectively.The diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter(P<0.05).The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency(AUC=0.970).CONCLUSION:SMA/SMV may be a potential marker for SISMAD.

Diagnosis of spontaneous isolated superior mesenteric artery dissection with ultrasound:A case report

BACKGROUND Spontaneous isolated superior mesenteric artery dissection(SISMAD)is a rare disease that originates from the superior mesenteric artery,without the presence of aortic and other arterial dissections.Most cases are diagnosed using contrastenhanced computed tomography(CECT),whereas the application of ultrasound is less common.CASE SUMMARY Here,we report a case of SISMAD with sudden epigastric pain that worsened as the main symptom after eating.The patient had a long history of hypertension with unknown blood pressure control but no history of smoking or alcohol consumption.This case was initially diagnosed using ultrasound and the results were later confirmed by CECT.After admission,the patient fasted,followed by parenteral nutrition support and fluid supplementation to maintain electrolyte and acid–base balance.Metoprolol succinate sustained-release tablets and aspirin were given as nonoperative treatments.After 1 wk,the symptoms improved,and the patient was discharged.During telephone follow-up,the patient did not develop similar symptoms.CONCLUSION Whether ultrasound can be used as a routine and noninvasive imaging method for the diagnosis of SISMAD needs further exploration.

A new three-step procedure for pancreatic head carcinoma with invasion of superior mesenteric artery

Pancreatic head carcinoma is characterized by high malignancy and a low survival rate and its mortality ranks fourth for malignant tumors with a 5-year survival rate of only 5%[1].Treatment of this cancer relies on surgical resection.However,the resection rate is only about 20%,because majority of the patients are classified as unresectable when diagnosed due to distant metastasis or

Clinical outcomes of transcatheter selective superior mesenteric artery urokinase infusion therapy vs transjugular intrahepatic portosystemic shunt in patients with cirrhosis and acute portal vein thrombosis

AIM To compare the outcomes of transcatheter superior mesenteric artery(SMA) urokinase infusion and transjugular intrahepatic portosystemic shunt(TIPS) for acute portal vein thrombosis(PVT) in cirrhosis.METHODS From January 2013 to December 2014, patients with liver cirrhosis and acute symptomatic PVT who met the inclusion criteria were randomly assigned to either an SMA group or a TIPS group. The two groups accepted transcatheter selective SMA urokinase infusion therapyand TIPS, respectively. The total follow-up time was24 mo. The primary outcome measure was the change in portal vein patency status which was evaluated by angio-computed tomography or Doppler ultrasound.Secondary outcomes were rebleeding and hepatic encephalopathy.RESULTS A total of 40 patients were enrolled, with 20 assigned to the SMA group and 20 to the TIPS group. The symptoms of all patients in the two groups improved within 48 h. PVT was improved in 17(85%) patients in the SMA group and 14(70%) patients in the TIPS group. The main portal vein(MPV) thrombosis was significantly reduced in both groups(P < 0.001), and there was no significant difference between them(P= 0.304). In the SMA group, superior mesenteric vein(SMV) thrombosis and splenic vein(SV) thrombosis were significantly reduced(P = 0.048 and P = 0.02),which did not occur in the TIPS group. At 6-, 12-,and 24-mo follow-up, in the SMA group and the TIPS group, the cumulative rates free of the first episode of rebleeding were 80%, 65%, and 45% vs 90%, 80%,and 60%, respectively(P = 0.320); the cumulative rates free of the first episode of hepatic encephalopathy were 85%, 80%, and 65% vs 50%, 40%, and 35%,respectively(P = 0.022).CONCLUSION Transcatheter selective SMA urokinase infusion and TIPS are safe and effective for acute symptomatic PVT in cirrhosis.

Mesenteric lymph reperfusion may exacerbate brain injury in a rat model of superior mesenteric artery occlusion shock

BACKGROUND：The intestinal lymphatic pathway and intestinal ischemia/reperfusion are mainly involved in mesenteric lymph duct ligation or drainage; moreover,intervention by reducing the lymph liquid reflux might relieve lung and other organ dysfunction induced by intestinal ischemia/reperfusion; however,research addressing mesenteric lymph reperfusion （MLR） and brain injury has not yet to be reported.OBJECTIVE：To observe the effect of MLR on brain tissue in a rat model of superior mesenteric artery occlusion （SMAO） shock,and to explore the molecular mechanism of MLR.DESIGN,TIME AND SETTING：A randomized,controlled,animal experiment at a neuro-pathophysiology level was performed at the Institute of Microcirculation,Hebei North University; Department of Pathophysiology,Basic Medical College; Department of Pathology,the First Hospital of Hebei North University between December 2007 and March 2009.MATERIALS：Adenosine triphosphate （ATP） standard was provided by the National Institute for the Control of Pharmaceutical and Biological Products; lactic acid （LA）,superoxide dismutase （SOD）,malonaldehyde （MDA）,nitrogen monoxidum （NO）,nitric oxide synthase （NOS）,myeloperoxidase （MPO） and ATPase assay kits were provided by Nanjing Jiancheng Bioengineering Institute,China.METHODS：A total of 24 male Wistar rats were randomly divided into four groups.In the sham-surgery group （n = 6）,both the mesenteric lymph duct and the superior mesenteric artery were not blocked; in the MLR group （n = 6）,the mesenteric lymph duct was occluded for 1 hour followed by 2-hour reperfusion; in the SMAO group （n = 6）,the superior mesenteric artery was occluded for 1 hour followed by 2-hour reperfusion; in the MLR ＋ SMAO group （n = 6）,both the mesenteric lymph duct and superior mesenteric artery were occluded for 1 hour followed by 2-hour reperfusion.MAIN OUTCOME MEASURES：Mean arterial blood pressure prior to and following ischemia/reperfusion; brain tissue morphology levels of LA,MDA,SOD,NO,NOS,MPO,ATPase and ATP following reperfusion.RESULTS：MLR did not cause changes in mean arterial blood pressure,brain tissue morphology,LA,MDA,NO,ATP,SOD,NOS,MPO and ATPase.However,SMAO caused a rapid decrease and gradual increase of mean arterial blood pressure.Neuronal necrosis,degeneration and swelling were observed in brain tissue.Contents of MDA,NO,LA and ATP as well as activities of NOS and MPO were significantly increased （P〈 0.05）,but activities of SOD and Na＋-K＋-ATPase were significantly decreased （P 〈 0.05）.MLR aggravated neuronal damage in a rat model of SMAO shock.Following MLR,mean arterial blood pressure was significantly decreased （P 〈 0.05）,contents of MDA and NO as well as activities of NOS and MPO were significantly increased （P 〈0.05）,but activities of Ca2＋-ATPase,Mg2＋-ATPase and Ca2＋-Mg2＋-ATPase as well as ATP content were significantly decreased （P〈 0.05）.CONCLUSION：MLR aggravates brain injury in a rat model of SMAO shock,which correlates with oxygen-derived free radical injury,NO synthesis and release,sequestration of neutrophilic granulocytes,decreasing activity of cell membrane pumps and energy metabolism dysfunction.Pathogenesis of the intestinal lymphatic pathway should be thoroughly investigated to prevent ischemia/reperfusion injury.

Pancreaticoduodenectomy with early superior mesenteric artery dissection

BACKGROUND: Pancreatic adenocarcinoma remains the fourth leading cause of cancer-related death and is one of the most aggressive human tumors. At present, surgical resection is the only potentially curative treatment. Early neck division is inadequate when invasion of the superior mesenteric artery (SMA) is suspected or in cases of replaced or accessory right hepatic artery. Malignant periampullary tumors often invade retroperitoneal peripancreatic tissues and a positive resection margin is associated with a poor long-term survival. DATA SOURCES: English-language medical databases, PubMed, ELSEVIER and SPRINGERLINK, were searched for articles on 'posterior approach pancreaticoduodenectomy', 'superior mesenteric artery first approach', 'retroperitoneal tissue', 'hanging maneuver', and related topics. RESULTS: The modification allowed the surgeon to early identify the nonresectability of a replaced right hepatic artery if present, enabling complete dissection of the right side of the SMA and portal vein as well as complete excision of the retroportal pancreatic lamina. CONCLUSION: Pancreaticoduodenectomy with early retropancreatic dissection is a useful and safe technical variant, which is indicated for the improvement of the safety and curative effect of the procedure. (Hepatobiliary Pancreat Dis Int 2010; 9: 579-583)

Influence of mesenteric lymph reperfusion on neurotransmitter expression in brain tissue of a superior mesenteric artery occlusion shock rat model

BACKGROUND： Previous studies have shown that mesenteric lymph reperfusion （MLR） exacerbates brain injury in a rat model of superior mesenteric artery occlusion （SMAO） shock. However, little is known about the influence of MLR on neurotransmitter expression in brain tissue. OBJECTIVE： To observe the effect of MLR on brain tissue injury by measuring monoamine and cholinergic neurotransmitter levels. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Institute of Microcirculation, Hebei North University, China; Research Room of Microcirculation and Laboratory of Biochemistry, Department of Pathophysiology, Basic Medical College, Hebei North University between December 2007 and March 2009. MATERIALS： Choline acetyltransferase （CHAT） and acetylcholine esterase （ACHE） kits were provided by Nanjing Jiancheng Bioengineering Institute, China; dopamine （DA） and noradrenalin （NE） standards were provided by the National Institute for the Control of Pharmaceutical and Biological Products; HP1100 chromatograph of liquid was provided by Agllent, USA. METHODS： A total of 24 male, Wistar rats were randomly assigned to 4 groups： sham-surgery, MLR SMAO, and MLR ＋ SMAO groups, with 6 rats in each group. In the MLR or SMAO groups, the mesenteric lymph duct or superior mesenteric artery was blocked for 1 hour. In the MLR ＋ SMAO group, the mesenteric lymph duct and superior mesenteric artery were occluded for 1 hour, followed by 2-hour repeffusion. ChAT and AChE levels were measured using the synthesized and hydrolyzed acetylcholine method, respectively. Liquid chromatography was employed to quantitatively analyze DA and NE levels, using relative retention time and the external standard method. MAIN OUTCOME MEASURES： CHAT, ACHE, DA, and NE levels. RESULTS： AChE levels were significantly increased, but ChAT levels were significantly decreased in the MLR and MLR ＋ SMAO groups following 2-hour repeffusion （P〈 0.01）. However, AChE activity in the MLR ＋ SMAO group was greater than in the MLR group （P 〈 0.05）. DA and NE levels were significantly decreased in the SMAO and MLR ＋ SMAO groups （P〈 0.01）, while DA levels in the MLR ＋ SMAO group were less than in the SMAO group （P 〈 0.05）. CONCLUSION： MLR exacerbated brain injury in a rat model of SMAO shock, which correlated with the intestinal lymphatic pathway. MLR decreased DA levels, but increased AChE activity, in a rat model of SMAO shock.

Diagnosis of ruptured superior mesenteric artery aneurysm mimicking a pancreatic mass

Aneurysms and pseudoaneurysms of the superior mesenteric artery are potentially lethal and should be treated as urgently as possible.In a 52-year-old man with occasional epigastric pain,we accidentally discovered a superior mesenteric artery aneurysm that was ruptured with spontaneous tamponade in the uncinate process and in the head of the pancreas.The ruptured aneurysm had a heterogeneous appearance due to its thrombotic and hemorrhagic content,and it simulated a voluminous mass in the head and uncinate process of the pancreas,associated with mild dilatation of the main pancreatic duct.Recent advances in multidetector computed tomography and magnetic resonance imaging have enabled radiologists to develop a correct diagnosis of mesenteric aneurysms and pseudoaneurysms of the visceral branches of the abdominal aorta,and to differentiate this diagnosis from that of pancreatic or peripancreatic masses;angiography is currently used to confirm a diagnosis and to develop therapeutic treatments.

Comparison of invasive dynamic blood pressure between superior mesenteric artery and common carotid artery in rats

The purpose of this study was to identify the consistency of invasive dynamic blood pressure (BP) monitoring between the superior mesenteric artery (SMA) and the common carotid artery (CCA). METHODS: Eight male Sprague-Dawley rats were cannulated in SMA and CCA simultaneously for BP monitoring, respectively. The abdominal aorta was prepared for the induction of BP change through clamping/de-clamping by a microvascular clip. The dynamic BP monitoring was performed by a polygraph system. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) values would be recorded during different time periods: the baseline (T1), the increasing period after clamping (T2), the platform period during clamping (T3), the decreasing period after de-clamping (T4), and the final platform period (T5). Three trials were performed on each rat with 15-minute intervals between consecutive monitoring. RESULTS: Systolic BP showed no significant differences between SMA and CCA. However, significant difference was found in diastolic blood pressure except at T5 (P=0.534). Mean arterial pressure of two arteries were signi cantly different only at T1 (P=0.015). The strength of association was significantly high between BP measurements through SMA and CCA (P<0.001). The Bland- Altman analyses showed that mean bias of MAP changed no more than 5 mmHg and standard deviation less than 8 mmHg during T2 and T4, respectively. CONCLUSION: The study indicates SMA might be an alternative site for invasive BP monitoring during abdominal aorta occlusion and release, especially in cerebrovascular-related research.

Successful recanalization of acute superior mesenteric artery thrombotic occlusion with primary aspiration thrombectomy

Prompt revascularization of the superior mesenteric artery(SMA) thrombotic occlusion can prevent intestinal infarction and decrease necrosis of the bowel segment.Herein,we describe two cases who underwent successful endovascular recanalization for acute SMA thrombosis using a primary aspiration thrombectomy because of possible consequent laparotomy for survey of bowel viability.The two patients had dramatic pain reliefimmediately after the procedure and remained symptomfree during the follow-up period.

Role of clinical data and multidetector computed tomography findings in acute superior mesenteric artery embolism

BACKGROUND Superior mesenteric artery embolism(SMAE)has acute onset and fast progression,which seriously threatens the life of patients.Multidetector computed tomography(MDCT)is one of the most important diagnostic methods for SMAE,which plays an important role in the diagnosis and prognosis of SMAE.AIM To evaluate the value of combined clinical data and MDCT findings in the diagnosis of acute SMAE and predict the risk factors for SMAE-related death.METHODS Data from 53 SMAE patients who received abdominal MDCT multi-phase enhancement and superior mesenteric artery digital subtraction angiography examinations were collected.Univariate cox regression and multivariate cox model were used to analyze the correlation between death risk and clinical and computed tomography features in SMAE patients.RESULTS Univariate Cox regression model showed that intestinal wall thinning,intestinal wall pneumatosis,blood lactate>2.1 mmol/L and blood pH<7.35 increased the risk of death in patients with SMAE.After adjusting for age,sex,embolic involvement length and embolic distribution region,multivariate Cox regression model I showed that blood lactate>2.1 mmol/L(HR=5.26,95%CI:1.04-26.69,P=0.045)and intestinal wall thinning(HR=9.40,95%CI:1.05-83.46,P=0.044)were significantly increases the risk of death in patients with SMAE.CONCLUSION For patients with SAME,increased blood lactate and intestinal wall thinning are the risk factors for death;hence,close monitoring may reduce the mortality rate.Clinical observation combined with MDCT signs can significantly improve SMAE diagnosis.

Aspiration therapy for acute embolic occlusion of the superior mesenteric artery

BACKGROUND Embolic superior mesenteric artery(SMA) occlusion is associated with high mortality rates. Delayed treatment often leads to serious consequences, including intestinal necrosis, resection, and even patient death. Endovascular repair is being introduced, which can improve clinical symptoms and prognosis and decrease the incidence of exploratory laparotomy. Many reports have described successful endovascular revascularization of embolic SMA occlusion. However,most of those reports are case reports, and there are few reports on Chinese patients. In this paper, we describe the technical and clinical outcomes of aspiration therapy using a guiding catheter and long sheath technique which facilitates the endovascular repair procedure.AIM To evaluate the complications, feasibility, effectiveness, and safety of endovascular treatment for the acute embolic occlusion of the SMA.METHODS This retrospective study reviewed eight patients(six males and two females)from August 2013 to October 2018 at Xuanwu Hospital, Capital Medical University. The patients presented with acute embolic occlusion of the SMA on admission and were initially diagnosed by computed tomography angiography(CTA). The patients who underwent endovascular treatment with a guiding catheter had no obvious evidence of bowel infarct. No intestinal necrosis was identified by gastrointestinal surgeons through peritoneal puncture or CTA. The complications, feasibility, effectiveness, safety, and mortality were assessed.RESULTS Six(75%) patients were male, and the mean patient age was 70.00 ± 8.43 years(range, 60-84 years). The acute embolic occlusion of the SMA was initially diagnosed by CTA. All patients had undertaken anticoagulation primarily, and percutaneous aspiration using a guiding catheter was then undertaken because the emboli had large amounts of thrombus residue. No death occurred among the patients. Complete patency of the suffering artery trunk was achieved in six patients, and defect filling was accomplished in two patients. The in-hospital mortality was 0%. The overall 12-mo survival rate was 100%. All patients survived, and two of the eight patients had complications(the clot broke off during aspiration).CONCLUSION Aspiration therapy is feasible, safe, and beneficial for acute embolic SMA occlusion. Aspiration therapy has many benefits for reducing patients' death,resolving thrombi, and improving symptoms.

Value of Multi-detector CT in Detection of Isolated Spontaneous Superior Mesenteric Artery Dissection

Objective To investigate the role of multi-detector computed tomography(CT) in the diagnosis and classification of isolated spontaneous superior mesenteric artery dissection(ISSMAD). Methods From July 2012 to December 2016,30 consecutive patients with ISSMAD underwent CT scan at least two times. We retrospectively summarized the clinical characteristics and CT findings of them. The stenosis ratio of true lumen was compared between the patients without bowel ischemia and ones with bowel ischemia. Results There were 5 cases of type I ISSMAD,14 cases of type Ⅱ,1 case of type Ⅲ,7 cases of type Ⅳ and 3 cases of type V. Intestinal ischemia occurred in 5 patients. The stenosis ratio of true lumen in the patients without bowel ischemia was lower than that with bowel ischemia(45.6% vs. 76.0%,t=–14.5,P=0.000). Five patients with intestinal ischemia underwent superior mesenteric artery stenting and others received conservative therapy. The abdominal pain was alleviated for all the patients after treatment. Follow-up was complete in 30 cases. Follow-up CT angiography of superior mesenteric artery showed dissection remodeling in 12 patients. Conclusion Multi-detector CT is a valuable method in diagnosis and classification of ISSMAD and monitoring the changes of dissection.

Management of isolated superior mesenteric artery dissection

AIM:To evaluate our experience of the clinical management of spontaneous isolated superior mesenteric artery dissection(ISMAD).METHODS:From January 2008 to July 2013,18 patients with ISMAD were retrospectively analyzed,including 7 patients who received conservative therapy,9patients who received reconstruction with bare stents,and 2 patients who underwent surgical treatment.The decision to intervene was based on anatomic suitability,patient comorbidities and symptoms.RESULTS:Intestinal ischemia-related symptoms completely resolved in 7 patients who received conservative therapy.Stent placement was successful in 9patients.Of the 9 patients who received endovascular stenting,abdominal pain was alleviated after the procedure and gradually disappeared within 3 d.Followup computed tomography and computed tomography angiography were available in all patients during the first month and the first year after the procedure,which revealed patent stent and patent involved superior mesenteric artery branches with complete obliteration of the dissection lesion.In the 2 patients who underwent surgical treatment,good clinical efficacy was also observed.CONCLUSION:ISMAD may be managed successfully in a variety of ways based on the clinical symptoms.ISMAD should be treated by conservative management as the first-line option,however,in those with bowel necrosis or imminent arterial rupture during conservative therapy,endovascular or surgical therapy is indicated.

Surgical management of peritonitis secondary to acute superior mesenteric artery occlusion

Diagnosis of acute arterial mesenteric ischemia in the early stages is now possible using modern computed tomography with intravenous contrast enhancement and imaging in the arterial and/or portal phase.Most patients have acute superior mesenteric artery(SMA)occlusion,and a large proportion of these patients will develop peritonitis prior to mesenteric revascularization,and explorative laparotomy will therefore be necessary to evaluate the extent and severity of intestinal ischemia,and to perform bowel resections.The establishment of a hybrid operating room in vascular units in hospitals is most important to be able to perform successful intestinal revascularization.This review outlines current frontline surgical strategies to improve survival and minimize bowel morbidity in patients with peritonitis secondary to acute SMA occlusion.Explorative laparotomy needs to be performed first.Curative treatment is based upon intestinal revascularization followed by bowel resection.If no vascular imaging has been carried out,SMA angiography is performed.In case of embolic occlusion of the SMA,open embolectomy is performed followed by angiography.In case of thrombotic occlusion,the occlusive lesion can be recanalized retrograde from an exposed SMA,the guidewire snared from either the femoral or brachial artery,and stented with standard devices from these access sites.Bowel resections and sometimes gall bladder removal due to transmural infarctions are performed at initial laparotomy,leaving definitive bowel reconstructions to a planned second look laparotomy,according to the principles of damage control surgery.Patients with peritonitis secondary to acute SMA occlusion should be managed by both the general and vascular surgeon,and a hybrid revascularization approach is of utmost importance to improve outcomes.