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??Interventional therapy for acute mesenteric arterial ischemia LIU Bing??WANG Hai-jun. Department of Vascular Surgery??the First Affiliated Hospital of Harbin Medical University??Harbin 150001??China
Corresponding author??WANG Hai-jun??E-mail??13836162963@163.com
Abstract Acute superior mesenteric artery ischemia is a fatal emergency with multiple etiology??including acute mesenteric arterial embolus and thrombus??nonocclusive mesenteric ischemia and other rare conditions. The progression of the disease will eventually lead to massive intestinal necrosis with high mortality. Early diagnosis and operation can reduce the mortality effectively. The first choice of early treatment for acute superior mesenteric artery ischemia is interventional therapy??meanwhile essential strict indication and operation skill should be known well.     

Acute mesenteric ischemia after cardiopulmonary bypass.

Acute mesenteric ischemia is an uncommon but catastrophic event after cardiopulmonary bypass. From 1980 to 1990, 16,951 cardiac procedures requiring cardiopulmonary bypass were performed at Emory University Hospital in Atlanta, Ga. Eighteen patients (0.1%) had acute mesenteric ischemia that resulted in intestinal infarction. Emergency cardiac surgery had been performed in 16 of the 18 patients, and all 18 patients were vasopressor dependent for hemodynamic support after surgery. Diagnostic difficulties resulted in the diagnosis of intestinal infarction an average of 9 1/2 days after cardiopulmonary bypass. Nonocclusive mesenteric arterial ischemia was the determined cause in all cases. Statistically significant risk factors associated with acute mesenteric ischemia after cardiopulmonary bypass surgery included (1) emergency cardiac surgery (p less than 0.0001), (2) the use of an intraaortic balloon pump (p less than 0.0001), (3) failed angioplasty requiring emergency surgery (p = 0.0074), (4) prolonged pump time (p = 0.0093), and (5) advanced age (p = 0.0016). A high index of suspicion for mesenteric ischemia after cardiopulmonary bypass in patients with identified risk factors may decrease the diagnostic delay and lead to an improvement in the 67% mortality rate seen in this series.     

The acute mesenteric ischemia - not understood or incurable?

PURPOSE: Despite surgical research and progress, the high mortality of acute intestinal ischemia seems to be improved insignificantly over the past fifty years. In this study we analyzed the specific diagnostic and therapeutic problems of the disease in order to improve further management of acute mesenteric ischemia. Methods: From 1979 until 2000 64 patients (female 31, male 33) with a mean age of 64 (30-89) years underwent operation for primary intestinal ischemia at our institution. All medical and surgical records and imaging studies were reviewed retrospectively. Follow up consisted of clinical examination and duplex sonography. RESULTS: Only in 26 patients (41 %) a preoperative diagnostic work-up including angiography 12 and CT 14 was performed, whereas in 42 cases the intestinal ischemia was diagnosed during surgical exploration. Intestine malperfusion was caused primarily by venous thrombosis in 9 cases (14 %) and by arterial occlusive disease in 55 cases (86 %). Arterial disorders consisted of arterial thrombosis in 19 cases (30 %), arterial embolism in 18 cases (28 %), aortic or mesenteric artery dissection in 10 cases (15 %), non occlusive disease (NOD) in 5 cases (8 %), trauma 3 cases (5 %). Five different therapeutic strategies were applied: group I: Intestinal resection: 24 patients, anastomotic insufficiency 5 (39 %), mortality 11 (46 %), group II: intestinal artery revascularization: 5 patients, secondary patency rate 80 %, mortality 40 %, GROUP III: Intestinal artery revacularization and perfusion with Ringer's solution: 11 patients, mortality 8 (73 %), group IV intestinal artery revascularization and intestinal resection: 3 patients, mortality 100 %, group V intestinal artery revascularization and perfusion and intestinal resection: 3 patients, mortality 33 %. A second look operation was performed in 29 cases (40 %) and displayed malperfusion in 72 %. Only 21 of 64 patients survived the acute intestinal ischemia (in hospital mortality was 67 %). Delayed diagnostic and operation caused higher mortality (interval 10 hours: mortality 59 %, interval 37 hours mortality; 71 %, p = 0,06). Follow up after 61 (4-72) months of 21 patients (100 %) could be achieved. Ten patients (48 %) had meanwhile died, 5 patients (50) % as consequence of mesenteric ischemia, the others of unrelated reasons. Eleven patients are still alive without clinical signs of intestinal ischemia. CONCLUSIONS: Early diagnosis before hospitalisation and in-hospital (arteriography) and operation are essential to improve the outcome of patients with acute intestinal ischemia. To avoid short bowel syndrome bowel resection should be combined with mesenteric revascularization. Resection of malperfused bowel should be done cautiously and should be followed automatically by second look operations. Special expertise and good team work of visceral and vascular surgeons are required to achieve better therapeutic results.     

Long-term outcomes of endoluminal therapy for chronic atherosclerotic occlusive mesenteric disease

Percutaneous interventions for symptomatic chronic mesenteric arterial atherosclerosis are rapidly gaining popularity. This study evaluates the long-term anatomic and functional outcomes of endovascular therapy for chronic atherosclerotic occlusive mesenteric arterial disease at a tertiary referral academic medical center. A retrospective analysis of records from patients who underwent endovascular mesenteric arterial interventions between 1984 and 2006 for chronic mesenteric ischemia was performed. Cases of acute ischemia or cases with associated bowel resection were excluded. Results were standardized to current Society for Vascular Surgery (SVS) criteria. Kaplan-Meier survival analyses were performed to assess time-dependent outcomes. Factor analyses were performed using either a multivariate model for fixed variables or a Cox proportional hazard model for time-dependent variables. Data are presented as mean +/- SEM. Thirty-one patients (84% female, average age 70, range 43-90, years) with 41 visceral vessel interventions were identified. Indications for intervention included weight loss >10 kg (61%) and/or postprandial pain (94%). The median SVS comorbidity score was 15 (range 10-24). All had three-vessel athero-occlusive mesenteric disease with a median of two vessels occluded on angiography. The median number of vessels revascularized was two. In all cases stenosis, and not occlusion, was treated. The 90-day mortality was 20% and the major morbidity was 6%. While primary and assisted patency rates for the interventions at 7 years were 69 +/- 8% and 72 +/- 9%, respectively (mean +/- SE, n > or = 10), cumulative freedom from recurrent symptoms was only 56 +/- 10%. Twenty percent of the vessels developed restenosis at a median interval of 0.29 years (range 0.3-2.8), with a freedom from restenosis of 79 +/- 8% at 5 years. Fifty percent of these, all with recurrent symptoms, were reintervened successfully with balloon angioplasty and resolution of their symptoms. There was no significant difference between the celiac and superior mesenteric artery outcomes. The correlation of recurrent symptoms and restenosis was significant (p < 0.001). Endoluminal therapy for chronic mesenteric ischemia carries a low morbidity and mortality in a high-risk population. While anatomic patency remains high, long-term therapeutic benefit is not achieved. In its present iteration, endovascular therapy for mesenteric ischemia should be limited to those patients without an open surgical option.     

急性肠系膜动脉缺血的介入治疗

急性肠系膜缺血是较为少见的外科急重症,包括肠系膜动脉的栓塞和血栓形成、非阻塞性肠系膜缺血以及其他少见病因。病情发展最终导致大面积肠坏死,病死率极高。早期诊断和及时的手术干预能有效降低病死率。介入治疗是急性肠系膜动脉缺血早期首选治疗手段,需严格掌握适应证和操作技巧。     

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??Diagnosis and treatment of acute mesenteric arterial ischemia: A report of 28 cases WU Zhang-min??TANG Xiao-bin,KOU Lei, et al. Department of Vascular Surgery??Beijing Anzhen Hospital??Capital Medical College??Beijing 100029??China
Corresponding author??CHEN Zhong, E-mail??chenzhong8658@vip.sina.com
Abstract Objective To conclude the diagnosis and treatment experience for acute mesenteric arterial ischemia disease. Methods The clinical data of 28 patients suffered from acute mesenteric ischemia admitted from 2004 to 2013 in Department of Vascular Surgery, Beijing Anzhen Hospital of Capital Medical College were analyzed retrospectively. The data include medication and surgery. Results Among the total 28 patients??11 patients underwent thrombolectomy by Fogarty catheter including 6 patients underwent bowel resection??and the other 17 patients received conservative medication therapy. Two patients??7.1%??died. Conclusion It is urgent to diagnose and treat the acute superior mesenteric ischemic diseases. The medication and surgery are important methods to save patients’ live.     

Nonocclusive acute mesenteric ischemia

The authors present one case of acute mesenteric ischemia appeared to the patient 70 years old, with HTA and coronary heart disease with heart arrhythmia treated with angiotensin-converting-enzyme inhibitor, anti arrhythmia agents and antithrombin therapy (trombostop). Acute mesenteric ischemia is not an isolated clinical entity, but a complex of diseases, including acute mesenteric arterial embolus and thrombus, mesenteric venous thrombus and nonocclusive mesenteric ischemia. These diseases have common clinical features caused by impaired blood perfusion of the intestine, bacterial translocation and systemic inflammatory response syndrome. Reperfusion injury is another important feature of nonocclusive mesenteric ischemia. We discuss about the nonocclusive mesenteric ischemia is the most lethal form of acute mesenteric ischemia because of the poor understanding of its pathophysiology and its nonspecific symptoms, which often delay its diagnosis. Although acute mesenteric ischemia is still lethal and in-hospital mortality rates have remained high over the last few decades, accumulated knowledge on this condition is expected to improve its prognosis.     

Diagnosis and management of acute mesenteric ischemia

The prevalence of significant splanchnic arterial stenoses is increasing, but remains mostly asymptomatic due to abundant collateral circulation. Acute insufficiency of mesenteric arterial blood flow accounts for 60 to 70% of cases of mesenteric ischemia and results mostly from a superior mesenteric embolus. Despite major advances have been achieved in understanding the pathogenic mechanisms of bowel ischemia, its prognosis remains dismal with mortality rates about 60%. The diagnosis of acute mesenteric ischemia depends upon a high clinical suspicion, especially in patients with known risk factors. Rapid diagnosis is essential to prevent intestinal infarction. However, early signs and symptoms of mesenteric ischemia are non specific, and definitive diagnosis often requires radiologic examinations. Early and liberal implementation of angiography has been the major advance over the past 30 years which allowed increasing diagnostic accuracy of acute mesenteric ischemia. CT and MR-based angiographic techniques have emerged as alternatives less invasive and more accurate to analyse splanchnic vessels and evaluate bowel infarction. The goal of treatment of patients with acute mesenteric ischemia is to restore intestinal oxygenation as quickly as possible after initial management that includes rapid hemodynamic monitoring and support. Surgery should not be delayed in patients suspected of having intestinal necrosis.     

Fulminante nichtokklusive mesenteriale Ischämie nach Reperfusion einer hochgradig ischämischen Extremität mit septisch-toxischer Einschwemmung

Nonocclusive mesenteric ischemia (NOMI) is a poorly understood condition marked by progressive intestinal ischemia leading to infarction, sepsis, and death in a high proportion of patients. The mortality rate for this intestinal disorder remains high, even when the diagnosis is made early in the course of the disease. The majority of cases are associated with severe congestive heart failure with low cardiac output, or other illness resulting in dehydration, or the splanchnic vasoconstrictive effect of some medications. Reactive splanchnic vasoconstriction is responsible for nonocclusive ischemic enteritis. This paper presents a case of NOMI after arterial reconstruction of an infected ischemic extremity. A reactive spasm of the superior mesenteric artery in response to a general sepsis after reperfusion of the ischemic tissue was noted in this case. The patient recovered after a few hours following flushing perfusion of mesenteric arteries with alprostadil.     

Die akute mesenteriale Ischämie

Acute mesenteric ischemia represents an intensive medical emergency which, when untreated, leads to sepsis and multiorgan failure. Predictive factors for survival are the time duration between onset of symptoms and therapy, etiology,patient age, and immediate therapy with anticoagulants in case of acute mesenteric thrombosis. Pathologically raised laboratory parameters (lactate, acidosis, leukocytosis) are signs of advanced mesenteric ischemia. Therapy aims at reinstating arterial perfusion of ischemic and potentially life-threatening intestinal regions and at avoiding further ischemias or infarctions. Immediate vessel reconstruction (embolectomy, thrombectomy,TEA,bypass) can prevent mesenteric infarction and is therefore preferable to intestinal resection alone, as long as irreversible ischemia or sepsis are not present. If the degree of reperfusion is in question, the indication for "second-look laparotomy" is to be used generously.     

Mesenteric arterial steal syndrome secondary to bilateral lumbar sympathectomy

A case of acute mesenteric ischemia and massive intestinal infarction secondary to bilateral lumbar sympathectomy and without any other apparent precipitating factors is presented. Its characteristics and findings significantly agree with those described as part of the mesenteric arterial steal syndrome. Although this syndrome was originally described as secondary to surgical revascularization of the lower extremities, experimental studies have shown that lumbar sympathectomy, by means of reducing the peripheral vascular resistance in the lower extremities, similarly causes intense hemodynamic alteration of the mesenteric circulation due to the sudeen redistribution of blood flow to the lower limbs at the expense of the mesenteric flow. When marginally compensated occlusive mesenteric arterial disease exists prior to surgery, the sudden fall in the arterial pressure gradients in this vessel can precipitate the occlusion of these arteries, resulting in mesenteric ischemia and intestinal infarction. It has also been suggested that an intense vasospamodic neurogenic reflex in the mesenteric arteries is an important factor in the pathogenesis of this syndrome.     

Mesenteric Ischemia Affects Young Adults with Predisposition

An 8-year retrospective review of Indiana University Hospital records consisting of any patient age 18 to 40 years old who presented with arterial mesenteric ischemia was performed. Three patients were identified that met our criteria. The first patient was discovered to have a protein C deficiency. The second patient was afflicted with afibrinoginemia, a protein C and an antithrombin III deficiency. The third patient had been previously diagnosed with Takayasu's arteritis and had an elevated ESR. Each patient had a protracted course of symptoms before mesenteric disease was considered, confirmed by angiography, and treated by arterial bypass with/without bowel resection. All patients survived and are currently asymptomatic at an average of 2 years postoperatively. Mesenteric ischemia in patients under the age of 40, especially in the absence of cocaine use, is rare and often causes a delay in diagnosis and appropriate treatment. The high incidence of hypercoagulable states in our study cases suggests the need for a search for such disorders and the possible need for long-term anticoagulation therapy as a deterrent to recurrence.     

Two cases of small bowel ischemia due to unusual cause

The authors report 2 cases of small bowel ischemia due to unusual cause. In both cases, vasculopathy was the cause of ischemia, but with a different etiology. In the first case, a mesenteric inflammatory veno-occlusive disease, with striking features of extensive phlebitis and venulitis affecting the veins of the small intestine and mesentery, without arterial involvement of this district was observed and histological examination showed inflammatory lymphocytic infiltrates and myointimal hyperplasia of the veins. The second case affected by intestinal ischemia from secondary and multiple cholesterol embolism, the histological examination showed inflammatory infiltrates with (lymphocytes and granulocytes) in the vessels of submucosal mesenteric area, by loose intimal fibrosis incorporating cholesterol clefts. Both patients required surgical exploration with resection of ischemic bowel. In the second case laparoscopy was the initial approach which allowed to identify the extension of ischemia with special regard to the perforation. The ultimate diagnosis is possible only with histological examination. Clinically, patients show the general signs of intestinal ischemia with pain, vomiting and bloody diarrhea. Prognosis depends on the extension of the lesions and the early surgical treatment.     

Hepatic portal vein gas detected by point of care ultrasound

IntroductionPortal venous gas is a rare finding in adults and is typically associated with underlying intestinal ischemia. Portal venous gas can be detected by a bedside point of care ultrasound (POCUS) examination in adult patients in critical care units (CCU). Findings include echogenic bubbles flowing centrifugally throughout the portal venous system.Case presentationWe present the case of a 73-year-old female with advanced ischemic cardiomyopathy and cardiorenal syndrome who was managed in the CCU. She developed vague abdominal pain and respiratory depression requiring intubation and dialysis during her course of treatment in the CCU. Her findings were consistent with portal venous gas upon POCUS, prompting computed tomography of her abdomen and surgical consultation. She was ultimately found to have nonobstructive mesenteric ischemia.Clinical discussionPVG is an ominous radiological sign and reflects intestinal ischemia in up to 72% of cases. Acute mesenteric ischemia of the small bowel could be due to occlusive or nonocclusive obstruction of the arterial blood supply or obstruction of venous outflow. Nonocclusive obstruction accounts for 5% to 15% of patients with acute mesenteric ischemia.ConclusionWith the increasing use of POCUS, critical care physicians should be aware of findings consistent with portal venous gas as a bedside tool for directing the treating physician toward an ominous diagnosis in patients with shock.     

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??Medical therapy in acute mesenteric arterial ischemia CHEN Zhong??ZHAI Meng-yao. Department of Vascular Surgery, Beijing Anzhen Hospital, Capital Medical College, Beijing 100029,China
Corresponding author??CHEN Zhong??E-mail??chenzhong8658@vip.sina.com
Abstract Acute mesenteric arterial ischemia is a vascular emergency with a low incidence. Several pathophysiologic events (arterial embolism, arterial thrombosis and diffuse vasospasm) lead to a sudden decrease in mesenteric blood flow. The mortality rate of mesenteric arterial ischemia remains high. The reason is insufficient understanding of its clinical picture in differential diagnosis of abdominal pain, thus there always is an unacceptable time delay before treatment. Every patient with acute mesenteric arterial ischemia must be diagnosed urgently and begin to receive therapy immediately. Therapeutic options vary from conservative resuscitation, medical treatment, endovascular therapy, surgical resection and revascularization. Prompt and appropriate medical treatment is the key to a better outcome and is the foundation of whole therapeutic process.     

Comparison of superficial femoral vein and saphenous vein as conduits for mesenteric arterial bypass

PURPOSE: Gangrenous bowel, intraabdominal sepsis, and previous failed mesenteric bypass are indications for use of an autogenous conduit for mesenteric arterial reconstruction. Saphenous vein (SV) is often used as the autogenous conduit of choice, but it may be prone to graft stenosis or occlusion. Recent experience with superficial femoral vein (SFV) suggests that it is an excellent alternative conduit for major arterial reconstruction. The purpose of this study was to compare the outcomes of SV and SFV for mesenteric arterial bypass. METHODS: During a 7-year period, 26 patients underwent 43 mesenteric arterial bypass procedures with autogenous conduit. SV was used for 23 bypasses (53%), and SFV was used for 20 bypasses (47%). Indications for revascularization included chronic mesenteric ischemia (n = 15; 58%), acute mesenteric ischemia (n = 9; 35%), and mycotic aneurysm of the paravisceral aorta (n = 2; 7%). Three patients (11%) underwent revascularization with SV grafts and two patients (8%) with SFV grafts after previous failed mesenteric bypass. RESULTS: The 30-day mortality rate was 15%. Three deaths occurred after SV bypass for acute mesenteric ischemia, and one death occurred after a SFV bypass for a ruptured paravisceral mycotic aneurysm. Twenty-two surviving patients were followed for a mean of 31 +/- 6 months. Three of 11 patients (27%) who survived after SV bypass had recurrent mesenteric ischemia develop (acute, n = 1; chronic, n = 2) from graft thrombosis at a mean interval of 32 +/- 22 months after surgery. No patient had recurrent symptoms develop after SFV bypass. One of the three patients with SV graft failure died of acute mesenteric ischemia, and the other two patients underwent successful bypass with SFV. Symptomatic graft failure was significantly more likely to occur in patients receiving SV grafts compared with SFV grafts (P <.05). CONCLUSION: SFV yields acceptable clinical outcomes for mesenteric arterial bypass compared with SV. SFV is a viable alternative to SV when autogenous conduit is indicated for mesenteric arterial reconstruction.     

Acute colorectal ischemia after aortic surgery: Pathophysiology and prognostic criteria

Acute colorectal ischemia is a rare though potentially lethal complication of aortic surgery. We reviewed our recent experience with 16 cases in order to analyze its causative and prognostic factors. The incidence was 2.8%, and the inferior mesenteric artery was occluded in all cases. All patients also had severe occlusive disease of at least two of the hypogastric or deep femoral arteries. Hypoperfusion due to arterial ligation, prosthetic occlusion or embolism was responsible in half the cases. Ischemia and perfusion due to aortic cross-clamping or perioperative hemorrhage were involved in the rest of the cases. Postoperative mortality was 31%. The mortality was lower for partial, nontransmural necrosis, and for elective operations. Recurrent intestinal ischemia, transmural necrosis, surgery for ruptured aneurysm, intestinal hemorrhage and pulmonary edema were associated with a higher mortality rate. All patients with anuria or extrarenal epuration and hepatic cytolysis died. Although reconstruction of the inferior mesenteric artery might lessen the incidence of postoperative colonic ischemia due to hypoperfusion, the role of oxygen free radicals should be investigated in humans, in order to afford colonic protection against the consequences of ischemia-reperfusion.Presented at the Annual Meeting of the Society de Chirurgie Vasculaire de Langue Française, June 23–24, 1989, Strasbourg, France.     

Duplex scanning for assessment of mesenteric ischemia

The accurate diagnosis of mesenteric arterial occlusive disease has in the past required invasive examination, primarily arteriography. Recent innovations in duplex ultrasound scan technology have for the first time provided a method for the noninvasive assessment of the splanchnic circulation in man. Mesenteric duplex scanning has been used successfully to measure postprandial changes in celiac and superior mesenteric arterial blood flow as well as changes in visceral flow produced by other pharmacologic stimuli.     

Perioperative diagnosis of mesenteric ischemia in acute aortic dissection by transesophageal echocardiography

Objective: Although computed tomography, angiography, or magnetic resonance imaging is most commonly used for diagnosing mesenteric ischemia caused by acute aortic dissection, use of these modalities is often limited in the perioperative period. Thus, we have introduced transesophageal echocardiography to cover this deficit. Purpose of this study is to report the feasibility and accuracy of transesophageal echocardiographic diagnosis on mesenteric ischemia. Methods: The consecutive 24 cases with acute aortic dissection which involved abdominal aorta and underwent surgery were examined. The celiac artery and superior mesenteric artery was visualized with 5 MHz biplane transesophageal echocardiography and was assessed for presence of dissection and blood flow in each of true and false lumen. The transesophageal echocardiographic findings were then correlated to the clinical course, computed tomographic findings, and laboratory data. Results: The celiac artery and superior mesenteric artery was successfully visualized in 24 cases (100%) and 23 cases (95.8%), respectively. Perfusion patterns in superior mesenteric artery were categorized into four patterns: (1) intact artery with adequate perfusion (type A: 14 cases); (2) dissection in the artery but with adequate perfusion in true lumen (type B: 5 cases); (3) dissection in the artery with narrowed true lumen compressed by false lumen without detectable blood flow (type C: 1 case); and (4) obstruction of arterial orifice by the intimal flap with narrowed true lumen in the proximal aorta (type D: 2 cases). One case with immediate postoperative death and another case with unsuccessful visualization of superior mesenteric artery were excluded from the analysis. Clinically apparent intestinal ischemia was present in three cases: one case with type C and two cases with type D, but in none of the remaining 19 cases with type A or type B (both sensitivity and specificity were 100%). The superior mesenteric artery was opacified in all of these three cases with ischemia. Conclusions: The transesophageal echocardiographic assessment is feasible in nearly all patients and potentially provides correct diagnosis on intestinal ischemia in the perioperative period of acute aortic dissection. Types C and D indicate significant mesenteric malperfusion.     

Acute mesenteric ischemia

Acute mesenteric ischemia is not an isolated clinical entity, but a complex of diseases, including acute mesenteric arterial embolus and thrombus, mesenteric venous thrombus, and nonocclusive mesenteric ischemia. These diseases have common clinical features caused by impaired blood perfusion to the intestine, bacterial translocation, and systemic inflammatory response syndrome. There is substantial evidence that the mortality associated with acute mesenteric ischemia varies according to its trigger cause. Nonocclusive mesenteric ischemia is the most lethal form of the acute mesenteric ischemia, because of the poor understanding of its pathophysiology and its mild and nonspecific symptoms, which often delay its diagnosis. Mesenteric venous thrombosis is much less lethal than acute thromboembolism of the superior mesenteric artery and nonocclusive mesenteric ischemia. In this articles we presents an overview of acute mesenteric ischemia, based on the research. Although the mortality rates, in acute mesenteric ischemia, have remained high over the last few decades, accumulated knowledge on this condition is expected to improve its prognosis.