Mesenteric Ischemia

Conservative Versus Endovascular Treatment for Spontaneous Isolated Superior Mesenteric Artery Dissection: A Clinical and Imaging Follow-up Study

PURPOSE

Spontaneous isolated superior mesenteric artery dissection (SISMAD) is a rare vascular disease, the treatment strategies for which remain debated. This retrospective study aimed to compare the outcomes of conservative and endovascular treatments in patients with SISMAD.

MATERIALS AND METHODS

Fifty-eight patients with SISMAD confirmed by computed tomography angiography admitted to our hospital between November 2017 and May 2021 and received confirmed conservative (n=43) or endovascular (n=15) treatment. The patient demographics, imaging analysis, and follow-up results were analyzed and compared.

RESULTS

The cohort included 54 males and 4 females with a mean age of 52 years. Abdominal pain was the major complaint (49/58, 84.5%), followed by chest pain (2/58, 3.4%). The mean follow-up was 9.1±7.9 months. The 2 main Sakamoto types were type III (27/58, 46.6%) and type IV (16/58, 27.6%). Most patients in both groups had angle 1 (aortomesenteric angle) and angle 2 (superior mesenteric artery [SMA] course) of over 80°. About 67.3% of patients had long length of dissection (>60 mm). The median distance between the SMA root and the dissection entry site was 1.5 cm, mostly (84.5% of the patients) in the curved segment of the SMA. Telephone follow-ups found that most patients survived pain-free, and none underwent intestinal resection. Only 4 patients, 2 in each group, had recurrent abdominal pain during follow-up and received stenting treatment to achieve complete vascular remodeling. Importantly, we found that the conservative and endovascular therapies achieved similar high remodeling rates (94% and 100%, respectively; p=0.335). The conservative group achieved satisfying vascular remodeling (partial, 35%; complete, 59%), making it as safe and effective a treatment as endovascular therapy.

CONCLUSIONS

Initial conservative management is safe and effective in patients with SISMAD. A high technical success rate and favorable short-term outcomes were associated with endovascular procedures as secondary interventions. It would be helpful to conduct large-scale, prospective, randomized controlled trials with long-term follow-up for SISMAD.

CLINICAL IMPACT

1. This research provided more detail clinical information, such as evaluation of abdominal pain and measurements of SMA angles, which is all relevant to treatment. 2. What's more, the most surprising results of follow-up part shown that conservative treatment could reached the remodeling rate as high as endovascular treatment, which was relatively low in other studies. It helps us share our treatment experience with clinicians. 3. In addition, we get limited knowledge about this rare disease, it's encouraging us to do more researches based on the results we had.

Therapeutic effect and study of human umbilical cord blood mononuclear cells in patients with ischaemic bowel disease

Ischaemic bowel disease (ICBD) is a group of intestinal ischaemia syndromes caused by various aetiologies of reduced intestinal blood flow or vascular occlusion. ICBD can present as abdominal pain, bloody stool, and diarrhoea. This disease often occurs in middle-aged and elderly individuals with cardiovascular and cerebrovascular diseases. The incidence of ischaemic bowel disease has been increasing for decades, and it is difficult to diagnose, resulting in rapid disease progression and a high mortality rate. Therefore, fully understanding this disease, improving the diagnosis rate of this disease, and finding appropriate treatment methods are urgently needed to improve the condition and prognosis of patients. Umbilical cord blood stem cells are accessible, have weak immunogenicity, and have various biological functions, such as angiogenesis, inflammation and immune regulation. Many studies have confirmed that cord blood stem cells can relieve ischaemia, and these cells have attracted tremendous amounts of attention in regenerative medicine in recent years. In this paper, we discuss the clinical characteristics of ICBD, analyse the characteristics of human umbilical cord blood mononuclear cells (HUCB-MNCs), and use its to treat ischaemic bowel disease. Additionally, we compare the clinical manifestations and related indicators before and after treatment to evaluate the efficacy and safety of these methods.

A Case Series on Acute Mesenteric Ischemia (AMI) Leading to Intestinal Gangrene Following Blunt Trauma to the Abdomen

The term "acute mesenteric ischemia" (AMI) refers to a set of conditions where the blood supply to various segments of the small intestine is cut off, causing ischemia and subsequent inflammatory changes that might result in bowel gangrene. Estimates place the incidence between 0.09% and 0.2% of all acute surgical hospitalizations. Early diagnosis is essential, despite the entity being a rare cause of abdominal discomfort, because if left untreated, mortality is 50%. Herein, we present a case series of three patients with bowel ischemia following blunt abdominal trauma.

Outcomes of Acute Mesenteric Ischemia in End-Stage Renal Disease and Predictors of Mortality: A Nationwide Assessment

Background Acute mesenteric ischemia (AMI) is an uncommon disease caused by obstruction of blood flow to the bowel, which can lead to high mortality rates. End-stage renal disease (ESRD) is another disease commonly seen in the elderly. There are limited data evaluating the relationship between AMI and ESRD, but it has been shown that ESRD patients have a higher risk of mesenteric ischemia than the general population. Methods This retrospective analysis utilized the National Inpatient Sample database for 2016, 2017, and 2018 to identify patients with AMI. Patients were then divided into two groups, AMI with ESRD and AMI only. All-cause in-patient mortality, hospital length of stay (LOS), and total costs were identified. The Student's t-test was used to analyze continuous variables, while Pearson's Chi-square test was used to analyze categorical variables. Results A total of 169,245 patients were identified, with 10,493 (6.2%) having ESRD. The AMI with ESRD group had a significantly higher mortality rate than the AMI-only group (8.5% vs 4.5%). Patients with ESRD had a longer LOS (7.4 days vs 5.3 days; P = 0.00), and higher total hospital cost ($91,520 vs $58,175; P = 0.00) compared to patients without ESRD. Conclusion The study found that patients with ESRD who were diagnosed with AMI had a significantly higher mortality rate, longer hospital stays, and higher hospital costs than patients without ESRD.

Collateral circulation develops in stenosis of the celiac trunk and superior mesenteric artery

PURPOSE

Mesenteric circulation is provided by the celiac trunk (CT), superior mesenteric artery (SMA), and inferior mesenteric artery (IMA). The collateral circulation between CT and SMA and between SMA and IMA plays a protective role against intestinal ischemia in case of narrowing or occlusion of the mesenteric vessels. In our study, it is aimed to determine the CT and SMA stenosis rates in patients with CT and SMA stenosis from angiography images, the occurrence of the collateral variations, and the frequency of these variations.

METHODS

A total of 408 non-selective or selective CT and SMA angiographic images were taken of 215 patients (130 males, 85 females) who were admitted to Akdeniz University Hospital with symptoms of chronic mesenteric ischemia (CMI) were included. The angiography images were analyzed in regards to CT and SMA stenosis rates, and the collateral variations between mesenteric vessels.

RESULTS

Stenosis of CT was observed in 14 patients, whereas the stenosis of the SMA was observed in 12 patients. The most common collateral vessel in these patients was the gastroduodenal artery. Both stenoses of CT and SMA were found in 9 patients. The Riolan arch was the most common type of collateral vessel in these patients.

CONCLUSION

It was observed that mesenteric circulation was mainly provided by gastroduodenal artery in patients with isolated CT or SMA stenosis or occlusion while in patients with stenosis or occlusion of both CT and SMA, mesenteric circulation was mainly provided by the Riolan arch. A significant increase was observed in the prominence of collateral vessels in patients with stenosis of more than 70%.

Surgical Emergencies in the ICU

Surgical emergencies are common in the critical care setting and require prompt diagnosis and management. Here, we discuss some of the surgical emergencies involving the gastrointestinal, hepatobiliary, and genitourinary sites. In addition, foreign body aspiration and necrotizing soft-tissue infections have been elaborated. Clinicians should be aware of the risk factors, keys examination findings, diagnostic modalities, and medical as well as surgical treatment options for these potentially fatal illnesses.

Post traumatic arterial occlusive mesenteric ischemia: a rare case report

Mesenteric ischemia is an uncommon condition with very high mortality rates characterized by inadequate blood supply, inflammatory injury, and subsequent necrosis of the bowel wall. Acute arterial mesenteric ischemia is usually caused by cardiac emboli, atherosclerotic vascular disease, aortic aneurysm, or dissection. We report a case of a 60-year-old male who presented to the accident and emergency department complaining of abdominal pain following blunt abdominal trauma. An urgent contrast enhanced computed tomography scan demonstrated superior mesenteric artery thrombosis with ischemic small bowel. Surgical intervention was carried out with resection of the necrotic bowel followed by anastomosis. Acute occlusive mesenteric ischemia needs to be considered in cases of blunt trauma presenting with abdominal pain. Proper early diagnosis and management is essential as it carries a high risk of morbidity and mortality.

Effect of Surgical Technique on the Microstructure and Microcirculation of the Small Intestine Stump during Delayed Anastomosis: Multimodal OCT Data

The aim of the study was to use multimodal optical coherence tomography (MM OCT) to evaluate microstructure and microcirculation in the proximal and distal sections of the intestine relative to the resected area in acute mesenteric ischemia.

Acute mesenteric ischemia and small bowel imaging findings in COVID-19: A comprehensive review of the literature

BACKGROUND

Coronavirus disease 2019 (COVID-19), an infectious condition caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread worldwide since its first description in Wuhan in December 2019. Even though respiratory manifestations are the most prevalent and responsible for disease morbidity and mortality, extrapulmonary involvement has progressively gained relevance. In particular, gastrointestinal (GI) signs and symptoms, reported in up to two-thirds of patients with COVID-19, might represent the first and, in some cases, the only disease presentation. Their presence has been associated in some studies with an increased risk of a severe disease course. Proposed pathogenic mechanisms explaining GI tract involvement are either direct viral access to intestinal cells via angiotensin-converting enzyme 2 or indirect damage of the intestinal wall through mesenteric ischemia induced by the hypercoagulable state associated with COVID-19 infection. Although not typical of SARS-CoV-2 infection, several small bowel manifestations have been described in infected patients who underwent any form of abdominal imaging. The radiological findings were mainly reported in patients with abdominal symptoms, among which abdominal pain was the most common.

AIM

To discuss small bowel radiological manifestations of SARS-CoV-2 infection in abdominal imaging studies.

METHODS

Bibliographical searches were performed in PubMed, using the following keywords: "COVID-19" AND "imaging" AND "gastrointestinal" OR "abdominal" OR "small bowel".

RESULTS

Of 62 patients with described radiologic small bowel alterations, mesenteric ischemia was diagnosed in 31 cases (50%), small bowel wall thickening in 10 cases (16%), pneumatosis in nine cases (15%), intussusception in eight cases (13%), pneumoperitoneum in two cases (3%) and paralytic ileus in two cases (3%). We also reported mesenteric adipose tissue hypertrophy and lymph nodes enlargement in a young woman.

CONCLUSION

So far it is difficult to establish whether these manifestations are the direct consequence of SARS-CoV-2 infection or collateral findings in infected patients, but their recognition would be pivotal to set a closer follow-up and to reduce missed diagnoses.

Many faces of acute bowel ischemia: overview of radiologic staging

Acute bowel ischemia (ABI) can be life threatening with high mortality rate. In spite of the advances made in diagnosis and treatment of ABI, no significant change has occurred in the mortality over the past decade. ABI is potentially reversible with prompt diagnosis. The radiologist plays a central role in the initial diagnosis and preventing progression to irreversible intestinal ischemic injury or bowel necrosis. The most single imaging findings described in the literature are either non-specific or only present in the late stages of ABI, urging the use of a constellation of features to reach a more confident diagnosis. While ABI has been traditionally categorized based on the etiology with a wide spectrum of imaging findings overlapped with each other, the final decision for patient's management is usually made on the stage of the ABI with respect to the underlying pathophysiology. In this review, we first discuss the pathologic stages of ischemia and then summarize the various imaging signs and causes of ABI. We also emphasize on the correlation of imaging findings and pathological staging of the disease. Finally, a management approach is proposed using combined clinical and radiological findings to determine whether the patient may benefit from surgery or not.

Estradiol prevented intestinal ischemia and reperfusion-induced changes in intestinal permeability and motility in male rats

OBJECTIVES

Ischemia and reperfusion (I/R) in the intestine could lead to severe endothelial injury, compromising intestinal motility. Reportedly, estradiol can control local and systemic inflammation induced by I/R injury. Thus, we investigated the effects of estradiol treatment on local repercussions in an intestinal I/R model.

METHODS

Rats were subjected to ischemia via the occlusion of the superior mesenteric artery (45 min) followed by reperfusion (2h). Thirty minutes after ischemia induction (E30), 17β-estradiol (E2) was administered as a single dose (280 μg/kg, intravenous). Sham-operated animals were used as controls.

RESULTS

I/R injury decreased intestinal motility and increased intestinal permeability, accompanied by reduced mesenteric endothelial nitric oxide synthase (eNOS) and endothelin (ET) protein expression. Additionally, the levels of serum injury markers and inflammatory mediators were elevated. Estradiol treatment improved intestinal motility, reduced intestinal permeability, and increased eNOS and ET expression. Levels of injury markers and inflammatory mediators were also reduced following estradiol treatment.

CONCLUSION

Collectively, our findings indicate that estradiol treatment can modulate the deleterious intestinal effects of I/R injury. Thus, estradiol mediates the improvement in gut barrier functions and prevents intestinal dysfunction, which may reduce the systemic inflammatory response.

Nutrient-induced hyperosmosis evokes vasorelaxation via TRPV1 channel-mediated, endothelium-dependent, hyperpolarisation in healthy and colitis mice

BACKGROUND AND PURPOSE

In humans, blood flow in the mesenteric circulation is greatly increased after meals, but the mechanisms underlying postprandial mesenteric vasorelaxation induced by nutrients and whether this process is involved in the pathogenesis of colitis, are not well understood. Here we have studied the direct actions of nutrients on mesenteric arterial tone and the underlying molecular mechanisms in healthy and colitis mice.

EXPERIMENTAL APPROACH

Colitis in C57BL/6 mice was induced with dextran sodium sulphate. Nutrient-induced vasorelaxation of mesenteric arterioles from humans and mice was studied with wire myograph assays. Ca²⁺ and Na⁺ imaging were performed in human vascular endothelial cells and vascular smooth muscle cells, using selective pharmacological agents and shRNA knockdown of TRPV1 channels.

KEY RESULTS

Glucose, sodium and mannitol concentration-dependently induced endothelium-dependent relaxation of human and mouse mesenteric arterioles via hyperosmotic action,. Hyperosmosis-induced vasorelaxation was almost abolished by selective blockers for TRPV1, IK_Ca and SK_Ca channels. Glucose markedly stimulated Ca²⁺ influx through endothelial TRPV1 channels, an effect attenuated by selective blockers and shRNA knockdown of TRPV1 channels. Capsaicin synergised the glucose-induced vasorelaxation. Nutrient-induced hyperosmosis also activated Na⁺ /K⁺ -ATPase and the Na/Ca exchanger (NCX) to decrease [Ca²⁺ ]_i in VSMCs. Glucose-induced vasorelaxation was impaired in mouse colitis.

CONCLUSION AND IMPLICATIONS

Nutrient-induced hyperosmosis evoked endothelium-dependent mesenteric vasorelaxation via the TRPV1/Ca²⁺ / endothelium-dependent hyperpolarisation pathway to increase normal mucosal perfusion, which is impaired in our model of colitis. The TRPV1/Ca²⁺ / endothelium-dependent hyperpolarisation pathway could provide novel drug targets for gastrointestinal diseases with hypoperfusion, such as chronic colitis and mesenteric ischaemia.

Risk of acute mesenteric ischemia in patients with diabetes: A population-based cohort study in Taiwan

BACKGROUND AND AIMS

Diabetes is a common and complex endocrine disorder that often results in hyperglycemia, which has been strongly implicated in several cardiovascular and cerebrovascular events that cause disability. Acute mesenteric ischemia (AMI) is a vascular emergency with high mortality rates. We conducted a population-based cohort study that utilizes data from medical claims databases to investigate whether diabetes increases the risk of AMI.

METHODS

Using claims data from Taiwan's National Health Insurance program, 66,624 diabetic patients were enrolled from 1998 to 2009, and a comparison group of 266,496 individually matched subjects without diabetes was selected. The two groups were followed up until diagnosis of AMI, death, or the end of 2011. Incidence rates of AMI were assessed in both groups. Cox proportional hazards models were used to estimate the hazard ratios of diabetes for AMI.

RESULTS

The diabetes cohort had a higher incidence rate than the comparison cohort for AMI (0.56 vs. 0.29 per 1,000 person-years). After adjusting for sex, age, comorbidity, and health system utilization, the adjusted hazard ratio of diabetes was 1.32 (95% confidence interval 1.11-1.56) for AMI. The risk of AMI associated with diabetes was greater in men (adjusted hazard ratio = 1.48, 95% confidence interval 1.17-1.87) than in women (adjusted hazard ratio = 1.17, 95% confidence interval 0.92-1.49).

CONCLUSIONS

There was an increased risk of AMI in patients with diabetes. However, further research is required to understand whether this association is causal or due to a common set of risk factors.