Predictive Factors for Intestinal Transmural Necrosis in Patients with Acute Mesenteric Ischemia

Selective minimally invasive strategy for acute superior mesenteric artery obstruction

OBJECTIVE

Acute mesenteric artery obstruction is a severe cause of acute mesenteric ischemia, associated with significant morbidity and mortality. However, there is limited guidance on choosing between traditional and minimally invasive techniques comprehensively. This study introduces a selective, minimally invasive strategy designed to improve the survival and prognosis of patients with acute superior mesenteric artery obstruction.

METHODS

In this prospective, single-arm trial conducted between 2020 and 2023, patients with acute mesenteric ischemia due to acute superior mesenteric artery obstruction were enrolled. A total of 42 patients were included, meeting the predetermined sample size. The primary outcome was the 30-day chronic intestinal failure (CIF)-free survival rate. Based on an algorithm incorporating preoperative radiographic findings, physical signs, and laboratory markers, patients were assigned to one of three therapeutic pathways: traditional laparotomy with thrombectomy, laparoscopy combined with endovascular therapy, or endovascular therapy alone.

RESULTS

The CIF-free survival rates at 30 days and 2 years were 71% (30/42) and 60%, respectively. Short-term mortality, including 30-day and in-hospital mortality, was 11.9%, indicating an improvement compared with historical cohorts. The cumulative mortality rates at 6 months, 1 year, and 2 years were 26%, 32%, and 32%, respectively. The primary and assisted patency rates at 1 year were 90% and 97%, respectively. Transition to laparotomy was required in 43% of patients undergoing laparoscopic exploration. Improved blood supply was observed in 73% of the patients who underwent two laparoscopic procedures (15 patients), and bowel resection was avoided in 40% of cases. The median durations of hospitalization and intensive care unit stay were 19 days (interquartile range, 11-31 days) and 2 days (interquartile range, 0-6 days), respectively.

CONCLUSIONS

This selective, minimally invasive strategy for managing acute mesenteric ischemia demonstrated high 30-day CIF-free survival rates and reduced short-term mortality. These findings suggest the potential advantages of this approach in improving outcomes for patients with acute mesenteric ischemia.

Radiological diagnosis of acute mesenteric ischemia in adult patients: a systematic review and meta-analysis

Computed tomography (CT) is widely used in diagnosing acute mesenteric ischemia (AMI), but robust identification of distinctive subtypes and stages of progression is lacking. Systematic literature search in PubMed, Cochrane Library, Web of Science and Scopus was conducted in May 2024. Studies including at least 10 adult patients and reporting radiological diagnosis of AMI versus no AMI or transmural ischemia versus no transmural ischemia were included. Meta-analyses on sensitivity and specificity of different radiological features in diagnosing AMI were conducted. From 2628 titles, 490 studies underwent full text review, and 81 were included in 14 meta-analyses. Diagnostic accuracy of CT angiography (CTA) was high - sensitivity of 92.0% and specificity of 98.8% (I2 45% and 79%, respectively), but lower for other CT protocols (sensitivity 75.8 and specificity 90.5; I2 83%). In most included studies, distinction of subtypes and severity of AMI (non-transmural or transmural) was not possible. Amongst the non-vascular features, absent/reduced bowel wall enhancement provided the best prognostic value (sensitivity 57.9 and specificity 90.1). CTA is the method of choice for diagnosing AMI with high diagnostic accuracy. None of the non-vascular features alone is sufficiently reliable to diagnose AMI or its progression to transmural necrosis, whereas a combination of different radiological features conveys a potential.

Diagnostic Performance of Clinical and Routine Laboratory Data in Acute Mesenteric Arterial Occlusion-An International Multicenter Study

BACKGROUND

There are no clinical or laboratory markers that can diagnose acute mesenteric ischemia (AMI) accurately. This study aimed to find differences in clinical and laboratory markers between arterial occlusive AMI and other acute abdominal diseases where AMI was initially suspected.

METHODS

This was a post hoc study of an international prospective multicenter study where data on patients with suspected AMI were collected. Independent factors associated with arterial occlusive AMI were evaluated in a multivariable logistic regression analysis.

RESULTS

The number of patients with arterial occlusive AMI was 231, consisting of thrombotic (n = 104), embolic (n = 61), and indeterminate (n = 66) occlusions. The non-AMI group included 287 patients, of whom 128 had strangulated bowel obstruction. Current smoking (odds ratio [OR] 2.56, 95% confidence interval [CI] 1.31-5.03), hypertension (OR 2.08, 95% CI 1.09-3.97), bowel emptying (OR 3.25, 95% CI 1.59-6.63), and leukocytosis (OR 1.54, 95% CI 1.14-2.08) at admission were independently associated with arterial occlusive AMI compared to the non-AMI group.

CONCLUSIONS

This study found clinical and laboratory data to be associated with arterial occlusive AMI in patients with suspicion of AMI, which can possibly be of value in screening for arterial occlusive AMI at the emergency department. Further studies are needed to find more accurate diagnostic markers.

Role of spleen density in predicting postoperative complications in patients with acute mesenteric ischemia

BACKGROUND

Acute mesenteric ischemia (AMI) is a life-threatening surgical emergency with a poor prognosis. This study assessed the association of diffuse reduction of spleen density (DROSD) with postoperative complications and identified risk factors for adverse outcomes in AMI patients after surgery.

METHODS

Patients who were diagnosed with AMI and underwent surgical operations between April 2006 and July 2021 were enrolled. Spleen density was assessed using preoperative non-enhanced computed tomography. The lowest quartile of spleen density in all patients was regarded as the cutoff value for DROSD. Univariate and multivariate analyses were performed to determine the risk factors related to postoperative outcomes after surgery.

RESULTS

According to the diagnostic cutoff, patients with a spleen density ≤49.07 HU were defined as DROSD. In a cohort of 97 patients, 34.0% developed complications within 30 days of surgery. The multivariate analysis illustrated that DROSD was an independent risk factor for prognostic outcomes in AMI patients after surgery.

CONCLUSION

Patients with low spleen density were prone to postoperative complications. As an imaging method, preoperative assessment of spleen density is a novel predictor that can be used clinically to identify high-risk AMI patients with poor prognosis.

Management of extensive portal vein thrombosis via thrombolysis and thrombectomy without underlying liver disease: A case report

Portal vein thrombosis (PVT) is a rare condition, particularly in non-cirrhotic patients. Anticoagulation remains the mainstay of the treatment. Extensive PVT can lead to variceal bleeding, ascites, bowel ischemia, and hypersplenism. The role of thrombolysis and thrombectomy in these patients remains unclear. However, there is evidence that local thrombolysis and thrombectomy should be considered in those who remain symptomatic on anticoagulation and are at risk of complications with acute PVT.

Irreversible Transmural Intestinal Necrosis in Acute Mesenteric Ischemia: Retrospective Cohort Study from a High-Volume Hospital

Background: Owing to the low incidence rate and nonspecific symptoms of acute mesenteric ischemia (AMI), the identification and prediction of irreversible transmural intestinal necrosis (ITIN) and extensive bowel resection (≥100 cm) (EBR) are difficult and critical. This study aimed to investigate the risk factors for ITIN and EBR in patients with AMI. Methods: The clinical data of 254 AMI patients were retrospectively analyzed. Furthermore, the incidence of ITIN and EBR were set as dependent variables, and relevant risk factors were screened using univariate and multivariate logistic regression analyses. The comparisons of surgical characteristics and postoperative recovery outcomes between the EBR and control group were also conducted. Results: The presence of hemorrhagic (odds ratio [OR] = 28.356, P < .001) or other types ascites (OR = 13.051, P = .003), peritonitis (OR = 8.463, P = .005), intestinal diameter >2.35 cm (OR = 5.493, P = .020), and serum creatinine (CREA) >95 μmol/L (OR = 4.866, P = .048) were identified as independent risk factors for ITIN in patients with AMI. In addition, serum C-reactive protein (CRP) >15 mg/L (OR = 38.023, P = .006), and CREA >100 μmol/L (OR = 6.248, P = .035) were proved to be independently associated with EBR for ITIN cases. Compared to the control group, EBR significantly increased the likelihood of requiring enterostomy (P = .001), blood transfusion (P = .002), and transfer to intensive care unit (P = .016), while also prolonging the recovery time for intestinal function (P = .014). Conclusions: The presence of ascites, peritonitis, intestinal diameter >2.35 cm, and serum CREA >95 μmol/L were independently correlated with ITIN for AMI cases, while serum CRP >15 mg/L and CREA >100 μmol/L independently increased the risk of EBR.

Predictors of Survival Without Intestinal Resection after First-Line Endovascular Revascularization in Patients with Acute Arterial Mesenteric Ischemia

Background Acute arterial mesenteric ischemia requires emergency treatment and is associated with high mortality rate and poor quality of life. Identifying factors associated with survival without intestinal resection (hereafter, intestinal resection-free [IRF] survival) could help in treatment decision-making after first-line endovascular revascularization. Purpose To identify factors associated with 30-day IRF survival in patients with acute arterial mesenteric ischemia whose first-line treatment was endovascular revascularization. Materials and Methods Patients with acute arterial mesenteric ischemia whose first-line treatment was endovascular revascularization because of a low probability of bowel necrosis were included in this single-center retrospective cohort (May 2014 to August 2022). Patient demographics, laboratory values, clinical characteristics at admission, CT scans, angiograms, and endovascular revascularization-related variables were included. The primary end point was 30-day IRF survival, and secondary end points were 3-month, 1-year, and 3-year overall survival. Factors independently associated with 30-day IRF survival were identified with binary logistic regression. Results A total of 117 patients (median age, 70 years [IQR, 60-77]; 53 female, 64 male) were included. Within 30 days after revascularization, 73 of 117 patients (62%) survived without resection, 28 of 117 (24%) survived after resection, 14 of 117 (12%) died without resection, and two of 117 (2%) underwent resection but died. The 30-day IRF survival was 63% (74 of 117). The 3-month, 1-year, and 3-year mortality rate was 18% (21 of 117), 21% (25 of 117), and 27% (32 of 117), respectively. Independent predictors of 30-day IRF survival were persistent bowel enhancement at initial CT (odds ratio [OR], 0.3; 95% CI: 0.2, 0.8; P = .013) and C-reactive protein (CRP) level less than 100 mg/L (OR, 0.3; 95% CI: 0.1, 0.8; P = .002). The 30-day IRF survival was 86%, 61%, 47%, and 23% in patients with both favorable features, persistent bowel enhancement but CRP level greater than 100 mg/L, no bowel enhancement but CRP level less than 100 mg/L, and both unfavorable features, respectively. Conclusion Independent predictors associated with 30-day IRF survival in patients with acute arterial mesenteric ischemia whose first-line treatment was endovascular revascularization were persistent bowel wall enhancement at initial CT and CRP level less than 100 mg/L. © RSNA, 2024 Supplemental material is available for this article.

The Diagnostic Value of Biomarkers in Acute Mesenteric Ischaemia Is Insufficiently Substantiated: A Systematic Review

OBJECTIVE

There is an urgent need for accurate biomarkers to support timely diagnosis of acute mesenteric ischaemia (AMI) and thereby improve clinical outcomes. With this systematic review, the aim was to substantiate the potential diagnostic value of biomarkers for arterial occlusive AMI.

DATA SOURCES

The Pubmed, Embase, and the Cochrane Library electronic databases were searched.

REVIEW METHODS

A systematic review of the literature has been conducted to define the potential diagnostic value of biomarkers for arterial occlusive AMI. All studies including ≥ 10 patients describing biomarkers for macrovascular occlusive AMI between 1950 and 17 February 2023 were identified within the Pubmed, Embase, and the Cochrane Library electronic databases. There were no restrictions to any particular study design, but letters and editorials were excluded. The QUADAS-2 tool was used for the critical appraisal of quality. The study protocol was registered on Prospero (CRD42021254970).

RESULTS

Fifty of 4334 studies were eligible for inclusion in this review. Ninety per cent of studies were of low quality. A total of 60 biomarkers were identified, with 24 in two or more studies and 15 in five or more studies. There was variation in reported units, normal range, and cut off values. Meta-analysis was not possible due to study heterogeneity. Biomarkers currently recommended by the European Journal of Vascular and Endovascular Surgery, European Society for Trauma and Emergency Surgery 2016, and World Society of Emergency Surgery 2017 guidelines also had heterogeneous low quality data for use in the diagnosis of AMI.

CONCLUSION

This systematic review demonstrates high heterogeneity and low quality of the available evidence on biomarkers for arterial occlusive AMI. No clinical conclusions can be drawn on a biomarker or combination of biomarkers for patients suspected of arterial occlusive AMI. Restraint is advised when rejecting or determining AMI solely based on biomarkers.

Correlation between white blood cell count and intestinal resection in patients with acute mesenteric vein thrombosis

OBJECTIVE

Acute mesenteric vein thrombosis (AMVT) is an acute abdominal disease with onset, rapid progression, and extensive intestinal necrosis that requires immediate surgical resection. The purpose of this study was to determine the risk factors for nosocomial intestinal resection in patients with AMVT.

METHODS

We retrospectively analysed 64 patients with AMVT diagnosed by CTA at the Affiliated Hospital of Kunming University of Science and Technology from January 2013 to December 2021. We compared patients who underwent intestinal resection (42 patients) with those who did not undergo intestinal resection (22 patients). The area under the ROC curve was evaluated, and a forest map was drawn.

RESULTS

Among the 64 patients, 6 (9.38%) had a fever, 60 (93.75%) had abdominal pain, 9 (14.06%) had a history of diabetes, 8 (12.5%) had a history of deep vein thrombosis (DVT), and 25 (39.06%) had ascites suggested by B ultrasound or CT after admission. The mean age of all patients was 49.86 ± 16.25 years. The mean age of the patients in the enterectomy group was 47.71 ± 16.20 years. The mean age of the patients in the conservative treatment group (without enterectomy) was 53.95 ± 15.90 years. In the univariate analysis, there were statistically significant differences in leukocyte count (P = 0.003), neutrophil count (P = 0.001), AST (P = 0.048), total bilirubin (P = 0.047), fibrinogen (P = 0.022) and DD2 (P = 0.024) between the two groups. The multivariate logistic regression analysis showed that admission white blood cell count (OR = 1.153, 95% CI: 1.039-1.280, P = 0.007) was an independent risk factor for intestinal resection in patients with AMVT. The ROC curve showed that the white blood cell count (AUC = 0.759 95% CI: 0.620-0.897; P = 0.001; optimal threshold: 7.815; sensitivity: 0.881; specificity: 0.636) had good predictive value for emergency enterectomy for AMVT.

CONCLUSIONS

Among patients with AMVT, patients with a higher white blood cell count at admission were more likely to have intestinal necrosis and require emergency enterectomy. This study is helpful for clinicians to accurately determine whether emergency intestinal resection is needed in patients with AMVT after admission, prevent further intestinal necrosis, and improve the prognosis of patients.

Penumbra aspiration thrombectomy of the superior mesenteric artery for mesenteric ischemia

Acute mesenteric ischemia from thromboembolic occlusion is a life-threatening emergency associated with a high mortality rate. Prompt diagnosis and intervention are vital to preserve viable bowel and prevent mortality. In the past decade, a shift has occurred toward minimally invasive alternatives such as endovascular therapies. We present a case of acute mesenteric ischemia from superior mesenteric artery thrombosis treated promptly with the Penumbra suction thrombectomy device (Penumbra Inc).

Insights into acute mesenteric ischaemia: an up-to-date, evidence-based review from a mesenteric stroke centre unit

Radiologists play a central role in the diagnostic and prognostic evaluation of patients with acute mesenteric ischaemia (AMI). Unfortunately, more than half of AMI patients undergo imaging with no prior suspicion of AMI, making identifying this disease even more difficult. A confirmed diagnosis of AMI is ideally made with dynamic contrast-enhanced CT but the diagnosis may be made on portal-venous phase images in appropriate clinical settings. AMI is diagnosed on CT based on the identification of vascular impairment and bowel ischaemic injury with no other cause. Moreover, radiologists must evaluate the probability of bowel necrosis, which will influence the treatment options.AMI is usually separated into different entities: arterial, venous, non-occlusive and ischaemic colitis. Arterial AMI can be occlusive or stenotic, the dominant causes being atherothrombosis, embolism and isolated superior mesenteric artery (SMA) dissection. The main finding in the bowel is decreased wall enhancement, and necrosis can be suspected when dilatation >25 mm is identified. Venous AMI is related to superior mesenteric vein (SMV) thrombosis as a result of a thrombophilic state (acquired or inherited), local injury (cancer, inflammation or trauma) or underlying SMV insufficiency. The dominant features in the bowel are hypoattenuating wall thickening with submucosal oedema. Decreased enhancement of the involved bowel suggests necrosis. Non-occlusive mesenteric ischaemia (NOMI) is related to impaired SMA flow following global hypoperfusion associated with low-flow states. There are numerous findings in the bowel characterised by diffuse extension. An absence of bowel enhancement and a thin bowel wall suggest necrosis in NOMI. Finally, ischaemic colitis is a sub-entity of arterial AMI and reflects localised colon ischaemia-reperfusion injury. The main CT finding is a thickened colon wall with fat stranding, which seems to be unrelated to SMA or inferior mesenteric artery lesions. A precise identification and description of vascular lesions, bowel involvement and features associated with transmural necrosis is needed to determine patient treatment and outcome.

Outcome of laparotomy and conservative treatment of patients with acute mesenteric venous ischemia with viable bowel

BACKGROUND

Acute mesenteric ischemia (AMI) is one of the most serious abdominal emergencies. Predicting the onset of bowel necrosis that warrants surgical intervention is of paramount importance in AMI. The present study aimed to investigate the outcome of patients with AMI secondary to mesenteric venous occlusion (MVO) and the consequence of non-therapeutic exploratory laparotomy.

METHODS

The records of 132 patients with AMI were retrospectively reviewed. The outcome of patients with acute mesenteric venous ischemia (AMVI) and viable bowel was analyzed based on the method of treatment: conservative versus surgical. The impact of non-therapeutic laparotomy on the outcome of patients with AMVI in terms of morbidity, readmission, and mortality was analyzed.

RESULTS

Forty-seven patients (34 male) with AMVI had viable bowel. Of the 47 patients with viable bowel, 8 (17%) had an exploratory non-therapeutic laparotomy, whereas 39 patients were treated conservatively. Patients who had non-therapeutic laparotomy had significantly higher complication (50 vs 5.1%, p = 0.005) and readmission rates (37.5 vs 5.1%, p = 0.03) and longer hospital stay (8.5 vs 7 days, p = 0.02) than those treated conservatively. Patients with bowel necrosis who had a therapeutic laparotomy had slightly lower rates of morbidity and mortality as compared to patients with viable bowel who underwent a non-therapeutic laparotomy.

CONCLUSION

Careful assessment and informed decision-making in patients with AMVI are crucial to avoid unnecessary surgical intervention that can result in higher rates of complications and readmission and extended hospital stay.

Basic demographic characteristics and prevalence of comorbidities in acute mesenteric ischemia: a systematic review and proportional meta-analysis

PURPOSE

The aim of this systematic review and meta-analysis was to examine and assess the basic demographic characteristics and prevalence of comorbidities in acute mesenteric ischemia (AMI) and its various subtypes.

PATIENTS AND METHODS

A literature search was conducted by using the databases PubMed, EMBASE, and Google Scholar (to June 1, 2022). Random-effects or fixed-effects models were selected to pool means and proportions and their corresponding 95% confidence intervals (CI), based on heterogeneity between studies. The results of meta-analyses for basic demographic characteristics and prevalence (proportions) of each specific comorbidities of acute mesenteric ischemia (AMI) and its various subtypes were described.

RESULTS

Ninety-nine studies were included in the meta-analysis, including 17,103 patients with AMI. Furthermore, 7941 patients with subclass diagnoses of AMI were identified, including 3,239 patients with arterial occlusive mesenteric ischemia (AOMI), 2,977 patients with nonocclusive mesenteric ischemia (NOMI), and 1,725 patients with mesenteric venous thrombosis (MVT). As a surgical emergency, AMI is associated with older patients and a high likelihood of multisystem comorbidities. Comorbidities of AMI involved multiple systemic diseases, including cardiovascular disease, endocrine and metabolic diseases, kidney diseases, digestive diseases, respiratory diseases, cerebrovascular diseases, vascular diseases, and cancer.

CONCLUSION

The basic demographic characteristics and the prevalence of comorbidities of different subtypes of AMI are different. The management of comorbidities should be an essential part of improving the prognosis of AMI patients and may contribute to precise prevention of AMI.

Radiological predictive factors of transmural intestinal necrosis in acute mesenteric ischemia: systematic review and meta-analysis

OBJECTIVE

Transmural intestinal necrosis (TIN) is related to high mortality in patients with acute mesenteric ischemia (AMI). Radiological predictive factors of TIN in AMI remains controversial. This study aimed to identify the CT-based predictive factors of TIN in AMI.

METHODS

EMBASE and PUBMED were searched for publications predicting TIN using radiological features. Quality Assessment of Diagnostic Accuracy Studies-2 was used to assess the methodological quality of individual studies. Data were presented in terms of diagnostic odds ratio (DOR), sensitivity, specificity, and 95% confidence interval (CI). The random-effects models were used for the meta-analysis.

RESULTS

Eleven studies including 1037 cases with AMI were considered. The meta-analysis showed that bowel wall thinning (DOR = 13.10; 95% CI: 3.71, 46.25), decreased or absent bowel wall enhancement (DOR = 5.77; 95% CI: 2.95, 11.30), bowel dilation (DOR = 3.23; 95% CI: 2.03, 5.15), pneumatosis intestinalis (DOR = 5.78; 95% CI: 2.24, 14.95), porto-mesenteric venous gas (DOR = 5.36; 95% CI: 2.14, 13.40), and arterial occlusive AMI (DOR = 2.66; 95% CI: 1.53, 4.63) were risk factors for predicting TIN. Bowel wall thinning and porto-mesenteric venous gas displayed high specificity to diagnose TIN (98%, 95%, respectively). The subgroup analysis showed that decreased or absent bowel wall enhancement (DOR = 8.23; 95% CI: 4.67, 14.51) and bowel dilation (DOR = 3.14; 95% CI: 1.55, 6.39) were predictors of TIN in venous occlusive AMI, which were not related to TIN in arterial-origin AMI.

CONCLUSIONS

For predicting TIN, there are specific radiological features. The radiological predictors of TIN may differ according to the various causes of AMI. Future primary studies should further evaluate the relationships between radiological signs and TIN based on different etiologies.

KEY POINTS

• Bowel wall thinning, decreased or absent bowel wall enhancement, bowel dilation, pneumatosis intestinalis, porto-mesenteric venous gas, and arterial occlusive AMI were risk factors for predicting TIN. • Decreased or absent bowel wall enhancement and bowel dilation were predictors of TIN in venous occlusive AMI, which were not related to TIN in arterial-origin AMI.

MRI for the Detection of Small Bowel Ischemic Injury in Arterial Acute Mesenteric Ischemia: Preclinical Study in a Porcine Model

BACKGROUND

MRI is the reference for the diagnosis of arterial cerebral ischemia, but its role in acute mesenteric ischemia (AMI) is poorly known.

PURPOSE

To assess MRI detection of early ischemic bowel lesions in a porcine model of arterial AMI.

STUDY TYPE

Prospective/cohort.

ANIMAL MODEL

Porcine model of arterial AMI obtained by embolization of the superior mesenteric artery (seven pigs).

FIELD STRENGTH/SEQUENCE

A 5-T. T1 gradient-echo-weighted-imaging (WI), half-Fourier-acquisition-single-shot-turbo-spin-echo, T2 turbo-spin-echo, true-fast-imaging-with-steady-precession (True-FISP), diffusion-weighted-echo-planar (DWI).

ASSESSMENT

T1-WI, T2-WI, and DWI were performed before and continuously after embolization for 6 hours. The signal intensity (SI) of the ischemic bowel was assessed visually and quantitatively on all sequences. The apparent diffusion coefficient (ADC) was assessed.

STATISTICAL TESTS

Paired Student's t-test or Mann-Whitney U-test, significance at P < 0.05.

RESULTS

One pig died from non-AMI-related causes. The remaining pigs underwent a median 5 h53 (range 1 h24-6 h01) of ischemia. Visually, the ischemic bowel showed signal hyperintensity on DWI-b800 after a median 85 (57-276) minutes compared to the nonischemic bowel. DWI-b800 SI significantly increased after 2 hours (+19%) and the ADC significant decrease within the first hour (-31%). The ischemic bowel was hyperintense on precontrast T1-WI after a median 87 (70-171) minutes with no significant quantitative changes over time (P = 0.46-0.93). The ischemic bowel was hyperintense on T2-WI in three pigs with a significant SI increase on True-FISP after 1 and 2 hours.

DATA CONCLUSION

Changes in SI and ADC can be seen early after the onset of arterial AMI with DWI. The value of T2-WI appears to be limited.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

Treatment of Acute Mesenteric Ischemia: Individual Challenges for Interventional Radiologists and Abdominal Surgeons

Background: Acute mesenteric ischemia (AMI) is a life-threatening condition resulting from occlusion of the mesenteric arterial vessels. AMI requires immediate treatment with revascularization of the occluded vessels. Purpose: to evaluate the technical success, clinical outcomes and survival of patients receiving endovascular treatment for AMI followed by surgery. Material and Methods: A search of our institution’s database for AMI revealed 149 potential patients between 08/2016 and 08/2021, of which 91 were excluded due to incomplete clinical data, insufficient imaging or missing follow-up laparoscopy. The final cohort included 58 consecutive patients [(median age 73.5 years [range: 43−96 years], 55% female), median BMI 26.2 kg/m2 (range:16.0−39.2 kg/m2)]. Periinterventional imaging regarding the cause of AMI (acute-embolic or acute-on-chronic) was evaluated by two radiologists in consensus. The extent of AMI and the degree of technical success was graded according to a modified TICI (Thrombolysis in Cerebral Infarction scale) score (TICI-AMI) classification (0: no perfusion; 1: minimal; 2a < 50% filling; 2b > 50%; 2c: near complete or slow; 3: complete). Lab data and clinical data were collected, including the results of follow-up laparoscopy. Non-parametric statistics were used. Results: All interventions were considered technically successful. The most common causes of AMI were emboli (51.7%) and acute-on-chronic thrombotic occlusions (37.9%). Initial imaging showed a TICI-AMI score of 0, 1 or 2a in 87.9% (n = 51) of patients. Post-therapeutic TICI-AMI scores improved significantly with 87.9% of patients grade 2b and better. Median lactate levels reduced from 2.7 (IQR 2.0−3.7) mg/dL (1−18) to 1.45 (IQR 0.99−1.90). Intestinal ischemia was documented in 79.1% of cases with resection of the infarcted intestinal loops. In total, 22/58 (37.9%) patients died during the first 30 days after intervention and surgery. According to CIRSE criteria, we did not observe any SAE scores of grade 2 or higher. Conclusions: AMI is a serious disease with high lethality within the first 30 days despite optimal treatment. However, interventional revascularization before surgery with resection of the infarcted bowel can save two out of three of critically ill patients.

Prediction and management of strangulated bowel obstruction: a multi-dimensional model analysis

BACKGROUND

Distinguishing strangulated bowel obstruction (StBO) from simple bowel obstruction (SiBO) still poses a challenge for emergency surgeons. We aimed to construct a predictive model that could distinctly discriminate StBO from SiBO based on the degree of bowel ischemia.

METHODS

The patients diagnosed with intestinal obstruction were enrolled and divided into SiBO group and StBO group. Binary logistic regression was applied to identify independent risk factors, and then predictive models based on radiological and multi-dimensional models were constructed. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were calculated to assess the accuracy of the predicted models. Via stratification analysis, we validated the multi-dimensional model in the prediction of transmural necrosis both in the training set and validation set.

RESULTS

Of the 281 patients with SBO, 45 (16.0%) were found to have StBO, while 236(84.0%) with SiBO. The AUC of the radiological model was 0.706 (95%CI, 0.617-0.795). In the multivariate analysis, seven risk factors including pain duration ≤ 3 days (OR = 3.775), rebound tenderness (OR = 5.201), low-to-absent bowel sounds (OR = 5.006), low levels of potassium (OR = 3.696) and sodium (OR = 3.753), high levels of BUN (OR = 4.349), high radiological score (OR = 11.264) were identified. The AUC of the multi-dimensional model was 0.857(95%CI, 0.793-0.920). In the stratification analysis, the proportion of patients with transmural necrosis was significantly greater in the high-risk group (24%) than in the medium-risk group (3%). No transmural necrosis was found in the low-risk group. The AUC of the validation set was 0.910 (95%CI, 0.843-0.976). None of patients in the low-risk and medium-risk score group suffered with StBO. However, all patients with bowel ischemia (12%) and necrosis (24%) were resorted into high-risk score group.

CONCLUSION

The novel multi-dimensional model offers a useful tool for predicting StBO. Clinical management could be performed according to the multivariate score.

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.

Predictors of transmural intestinal necrosis in patients presenting with acute mesenteric ischemia on computed tomography

PURPOSE

The purpose of this study was to identify the significant imaging predictors of transmural intestinal necrosis in patients with acute mesenteric ischemia (AMI).

METHODS

The medical records and CT imaging of 48 patients between 2011 and 2019 suspected of having AMI that underwent exploratory laparotomy with bowel resection and pathological confirmation of ischemic bowel injury were retrospectively reviewed. Using histopathology as a gold standard, various parameters related to vascular insufficiency and bowel injury were analyzed and correlated with outcome of ischemic bowel necrosis using nonparametric tests. Univariate analysis was performed using Fisher's exact test followed by binary logistic regression test for multivariate analysis.

RESULTS

48 Patients (19 females, 40%) with a median age of 68.5 years (IQR of 17 years) built our retrospective cohort. 26 (54%) patients were found to have transmural intestinal necrosis on histopathology (case group) whereas 22 (46%) patients had partial mucosal injury (control group). Pneumatosis intestinalis (p = 0.005, odd's ratio of 2.07-63.14) and severity (> 70% or complete occlusion) of vascular narrowing (p = 0.019, odd's ratio of 1.39-42.30) were identified as the most significant predictors of transmural ischemic necrosis on imaging. Dilatation of bowel did not approach the statistical significance on multivariate analysis although it was found significant on univariate analysis (p = 0.041).

CONCLUSION

Pneumatosis intestinalis and severity of vascular luminal narrowing are the most important imaging predictors of transmural ischemic bowel necrosis in patients presenting with AMI. The presence of these findings on CT scan should raise high index of suspicion for irreversible transmural ischemic necrosis. In the absence of these factors, endovascular management might be beneficial.

Successful treatment of acute spleno-porto-mesenteric vein thrombosis after ChAdOx1 nCoV-19 vaccine. A case report

Several cases of deep venous thrombosis in people who had recently received Vaxzevria (previously known as COVID-19 Vaccine AstraZeneca) have recently been reported, mainly presenting as cerebral vein/cerebral venous sinus thrombosis. This syndrome has been termed "vaccine-induced immune thrombotic thrombocytopenia (VITT)". Acute spleno-porto-mesenteric vein thrombosis is an uncommon but serious condition with potential sequelae, such as small-bowel gangrene and end-stage liver failure. We describe a case of concomitant thrombosis of portal, superior mesenteric and splenic veins in a young female patient with no other risk factors who received Vaxzevria (previously ChAdOx1 nCoV-19 vaccine, AstraZeneca) 17 days before. The diagnostic workup and the successful endovascular treatment and systemic anticoagulation management is reported.

Endovascular therapy in acute mesenteric ischemia after coronary artery bypass grafting: a case report and literature review

In the pattern of abdominal complications after cardiac surgery, acute mesenteric ischemia is rare but high-mortality pathology. In the initial stages, the disease has no specific signs, which makes it difficult to perform early multislice computed tomography to diagnose it. Risk stratification and an individual approach to the choice of diagnostic and therapeutic measures aimed at early restoration of mesenteric blood flow will reduce the mortality in this complication.

Endovascular Revascularization with Stent Implantation in Patients with Acute Mesenteric Ischemia due to Acute Arterial Thrombosis: Clinical Outcome and Predictive Factors

Purpose

To determine 30-day-mortality rates and identify predictors for survival in patients undergoing endovascular revascularization for acute mesenteric ischemia (AMI) due to occlusion of the celiac (CA) or superior mesenteric artery (SMA) from arterial thrombosis in the setting of atherosclerosis at the vessel origin.

Materials and Methods

A retrospective analysis on patients who underwent acute endovascular revascularization to treat AMI caused by thrombotic occlusion of the CA and/or SMA between January 2011 and December 2019 was conducted. 30-day-mortality rates were calculated. Univariate binomial logistic regression analyses (p < 0.05) were performed to assess whether the following factors were associated with 30-day mortality: sex, age, history of smoking, history of abdominal angina, signs of bowel necrosis on pre-interventional CT, one- vs. two-vessel disease, patency of the inferior mesenteric artery, outpatient or inpatient occurrence of ischemia, onset of AMI during ITU stay, elevated pre-interventional serum lactate levels, total leukocyte count, platelet/lymphocyte ratio and neutrophil/lymphocyte ratio.

Results

40 patients were included in this analysis. 30-day-mortality rate was 25/40 (62.5%). Median overall survival of patients who survived the first 30 days was 36 ± 18 months. None of the analyzed factors was statistically significantly associated with 30-day mortality.

Conclusion

Although mortality of patients with AMI due to acute arterial thrombosis remains high, almost 40% of patient who underwent emergent endovascular revascularization survived longer than one month. Since no predictors for the outcome in these patients were identified, all patients with AMI should be offered an immediate revascularization effort.

Diagnostic performance of CT for the detection of transmural bowel necrosis in non-occlusive mesenteric ischemia

OBJECTIVES

To evaluate the diagnostic performance of CT for transmural necrosis (TN) in non-occlusive mesenteric ischemia (NOMI) according to the bowel segment involved.

METHODS

From January 2009 to December 2019, all patients admitted to the intensive care unit (ICU) and requiring laparotomy for NOMI were retrospectively studied. CT had to have been performed within 24 h prior to laparotomy and were reviewed by two abdominal radiologists, with a consensus reading in case of disagreement. A set of CT features of mesenteric ischemia were assessed, separating the stomach, jejunum, ileum, and right (RC) and left colon (LC). Univariate and multivariate analyses were performed to identify features associated with TN. Its influence on overall survival (OS) was assessed.

RESULTS

Among 145 patients, 95 (66%) had ≥ 1 bowel segment with TN, including 7 (5%), 31 (21%), 43 (29%), 45 (31%), and 52 (35%) in the stomach, jejunum, ileum, RC, and LC, respectively. Overall inter-reader agreement of CT features was significantly lower in the colon than in the small bowel (0.59 [0.52-0.65] vs 0.74 [0.70-0.77] respectively). The absence of bowel wall enhancement was the only CT feature associated with TN by multivariate analysis, whatever the bowel segment involved. Proximal TN was associated with poorer OS (p < 0.001).

CONCLUSIONS

The absence of bowel wall enhancement remains the most consistent CT feature of transmural necrosis, whatever the bowel segment involved in NOMI. Inter-reader agreement of CT features is lower in the colon than in the small bowel. Proximal TN seems to be associated with poorer OS.

KEY POINTS

• The absence of bowel wall enhancement is the most consistent CT feature associated with transmural necrosis in NOMI, whatever is the bowel segment involved. • Inter-reader agreement is lower in the colon than in the small bowel in NOMI. • In NOMI, the more proximal the bowel necrosis, the worse the prognosis.

Acute type A aortic dissection with mesenteric malperfusion syndrome: a case report

BACKGROUND

Patients with acute type A aortic dissection and mesenteric malperfusion syndrome (mesMPS) have a high mortality rate. Therefore, the analysis of the timing of open aortic repair and intestinal operation is of great significance for the timely selection of clinical treatment.

CASE SUMMARY

The chief complaints of the patient were sudden chest and back bursting pain for 15 h. Emergency "ascending aorta replacement + total arch replacement (island flap anastomosis) + descending aorta stent implantation + coronary artery bypass grafting + autologous vascular access" was performed. The patient's postoperative occult blood test was positive. His blood stool was visible to the naked eye on the 11^th day after the open aortic repair. He had abdomen tenderness on the 12^th postoperative day. He had abdominal pain and was diagnosed by CT with intestinal obstruction on the 13^th postoperative day. Then, he underwent an emergency laparotomy for right hemicolectomy + partial resection of small intestine + cholecystectomy + ileostomy. He was discharged with diagnoses of aortic dissection (type A), coronary dissection, multiple perforations of the colon, congenital ectopic small bowel glands, and acute attack of chronic cholecystitis. More than a year later, he underwent "intestinal adhesion lysis + ileostomy closure + incisional hernia repair". The patient recovered well at the 1-year follow-up.

CONCLUSION

We have reported a case of acute type A aortic dissection with mesenteric malperfusion syndrome. In the early stage of mesenteric hypoperfusion syndrome, specific laboratory examination indexes and clinical manifestations are lacking, and mesenteric multidetector CT angiography is a first-line examination method for mesenteric malperfusion. Through the detailed analysis of the patient's condition and the review of the relevant literature, we hope to have a deeper understanding of this condition and provide evidence supporting the formulation of clinical treatment plan.

Predictors of bowel necrosis in patients with acute mesenteric ischemia: systematic review and meta-analysis

Acute mesenteric ischemia (AMI) is a serious medical condition that can progress to transmural bowel necrosis. Prediction of the onset of bowel necrosis in AMI is crucial to justify surgical intervention before more severe consequences supervene. This systematic review aimed to identify the significant predictors of bowel necrosis in AMI in the current literature. In adherence to the PRISMA guidelines, electronic databases were searched for studies that reported significant independent predictors of bowel necrosis in AMI. The quality of the studies was assessed with MINORS score. The main outcomes of the review were the incidence and predictors of bowel necrosis in patients with AMI and the mortality rate. This systematic review comprised nine articles that included 963 patients of a median age of 57 years. Irreversible bowel necrosis was found in 402 (41.7%) patients. The significant predictors of bowel necrosis were subdivided into eight clinical, seven biochemical, and six radiologic parameters. Eight parameters were reported by two or more studies, whereas 13 were reported by a single study. Based on the weight and odds ratio of the predictive parameters, a prognostic scoring system, Emile-Khan Score, was proposed. Several clinical, biochemical, and radiologic predictors of bowel necrosis were reported in the literature. Pooling of odds ratios was feasible for eight factors that were reported by more than one study. Further studies are needed to ascertain the utility of the other predictive factors.Level of evidence: Level II (systematic review and meta-analysis).

Management of Acute Mesenteric Venous Thrombosis: A Systematic Review of Contemporary Studies

Background and Aims:

Acute mesenteric venous thrombosis accounts for up to 20% of all patients with acute mesenteric ischemia in high-income countries. Acute mesenteric venous thrombosis is nowadays relatively more often diagnosed with intravenous contrast-enhanced computed tomography in the portal phase than at explorative laparotomy No high-quality comparative studies between anticoagulation alone, endovascular therapy, or surgery exists. The aim of the present systematic review was to offer a contemporary overview on management.

Materials and Methods:

Eleven relevant published original studies with series of at least ten patients were retrieved from a Pub Med search between 2015 and 2020 using the Medical Subject Heading term “mesenteric venous thrombosis.”

Results:

When MVT is diagnosed early, immediate anticoagulation with either unfractionated heparin or subcutaneous low-molecular-weight heparin should commence. Surgeons need to be aware of the importance to scrutinize the computed tomography images themselves for assessment of secondary intestinal abnormalities to mesenteric venous thrombosis and the risk of bowel resection and worse prognosis. Progression toward peritonitis is an indication for explorative laparotomy and assessment of bowel viability. Frank transmural small bowel necrosis should be resected and bowel anastomosis may be delayed for several days until second look. Meanwhile, intravenous full-dose unfractionated heparin should be given at the end of the first operation. Postoperative major intra-abdominal or gastrointestinal bleeding occurs rarely, but the heparin effect can instantaneously be reversed by protamine sulfate. Patients who do not improve during conservative therapy with anticoagulation alone but without developing peritonitis may be subjected to endovascular therapy in expert centers. When the patient’s intestinal function has recovered, with or without bowel resection, switch from parenteral unfractionated heparin or low-molecular-weight heparin therapy to oral anticoagulation can be performed. There is a trend that direct oral anticoagulants are increasingly used instead of vitamin K antagonists. Up to now, direct oral anticoagulants have been shown to be equally effective with the same rate of bleeding complications. Patients with no strong permanent trigger factor for mesenteric venous thrombosis such as intra-abdominal cancer should undergo blood screening for inherited and acquired thrombophilia.

Conclusion:

Early diagnosis with emergency computed tomography with intravenous contrast-enhancement and imaging in the portal phase and anticoagulation therapy is necessary to be able to have a succesful non-operative succesful course.

Predictors of irreversible intestinal resection in patients with acute mesenteric venous thrombosis

BACKGROUND

Acute mesenteric venous thrombosis (AMVT) can cause a poor prognosis. Prompt transcatheter thrombolysis (TT) can achieve early mesenteric revascularization. However, irreversible intestinal ischemia still occurs and the mechanism is still unclear.

AIM

To evaluate the clinical outcomes of and to identify predictive factors for irreversible intestinal ischemia requiring surgical resection in AMVT patients treated by TT.

METHODS

The records of consecutive patients with AMVT treated by TT from January 2010 to October 2017 were retrospectively analyzed. We compared patients who required resection of irreversible intestinal ischemia to patients who did not require.

RESULTS

Among 58 patients, prompt TT was carried out 28.5 h after admission. A total of 42 (72.4%) patients underwent arteriovenous combined thrombolysis, and 16 (27.6%) underwent arterial thrombolysis alone. The overall 30-d mortality rate was 8.6%. Irreversible intestinal ischemia was indicated in 32 (55.2%) patients, who had a higher 30-d mortality and a longer in-hospital stay than patients without resection. The significant independent predictors of irreversible intestinal ischemia were Acute Physiology and Chronic Health Evaluation (APACHE) II score (odds ratio = 2.368, 95% confidence interval: 1.047-5.357, P = 0.038) and leukocytosis (odds ratio = 2.058, 95% confidence interval: 1.085-3.903, P = 0.027). Using the receiver operating characteristic curve, the cutoff values of the APACHE II score and leukocytosis for predicting the onset of irreversible intestinal ischemia were calculated to be 8.5 and 12 × 109/L, respectively.

CONCLUSION

Prompt TT could achieve a favorable outcome in AMVT patients. High APACHE II score and leukocytosis can significantly predict the occurrence of irreversible intestinal ischemia. Therefore, close monitoring of these factors may help with the early identification of patients with irreversible intestinal ischemia, in whom ultimately surgical resection is required, before the initiation of TT.

Use of ultrasound findings to predict bowel ischemic changes in pediatric patients with intestinal volvulus

OBJECTIVES

Early diagnosis and prompt surgical intervention are important to prevent intestinal necrosis in patients with volvulus. The purpose of this study was to determine which ultrasound (US) findings may predict bowel ischemic changes in pediatric patients with intestinal volvulus.

METHODS

Thirty-one pediatric patients with surgically proven intestinal volvulus were retrospectively reviewed. We compared the demographics and US findings (eg, superior mesenteric artery collapse, ascites, echogenic ascites, and degree of intestinal twist) between patients with and without bowel ischemic changes during surgery. Data are presented as median and range. The Fisher exact test, Mann-Whitney U test, and Wilcoxon signed rank sum test were used for statistical analyses.

RESULTS

Eleven patients had bowel ischemic changes. Significant differences existed between patients with and without ischemic changes for age (2 days [range, 0-137 days] versus 6.5 days [range, 2-1618 days]; P = .02), superior mesenteric artery collapse (present/absent, 10/1 versus 9/11 patients; P = .02), the presence of ascites (present/absent, 8/3 versus 6/14 patients; P = .03), and intestinal twist degree on US imaging (540° [range, 180°-720°] versus 360° [range, 180°-720°]; P = .02). The groups did not significantly differ for sex, the time from the US examination to the operation, or echogenic ascites. The intestinal twist degree insignificantly differed between US and surgical findings (360° [range, 180°-720°] versus 360° [range, 0°-1080°]; P = .36).

CONCLUSIONS

The presence of superior mesenteric artery collapse, ascites, and a large intestinal twist on US imaging were significant predictors of intestinal ischemic changes. Pediatric surgeons should perform prompt surgical interventions in cases of volvulus with these US findings.

Predictive Factors of Intestinal Necrosis in Acute Mesenteric Ischemia

Objectives

Acute mesenteric ischemia (AMI) is a gastrointestinal and vascular emergency in which the detection of patients requiring intestinal resection is mandatory.

Methods

Registered data of 55 consecutive patients admitted to our center between January 2010 and December 2016 that underwent an explorative laparotomy for a suspected diagnosis of irreversible transmural intestinal necrosis (ITIN) were analyzed. Demographic, clinical, laboratory and CT findings were statistically analyzed in order to search predictive factors of ITIN and their correlation to its clinical spectre.

Results

Tobacco use was the most statistically significant (p<0.01) cardiovascular disease risk factor involved in ITIN. Among lab tests, Serum lactate levels ˃ 2mmol/L resulted in a statistically significant association with ITIN (p=0.0001). Organ failure (defined as Marshall score> 2) and the three main CT findings (decreased bowel wall enhancement, bowel loop dilation and demonstrated vessel occlusion) were strongly associated with ITIN (p values: 0.001, 0.007, 0.0013, 0.0005). Only serum lactate levels>2 mmol/L resulted as statistically significant as predictive factors of ITIN in multivariate analysis using logistic regression (OR 49.66 and p-value 0.0021).

Conclusion

Our univariate and multivariate analysis identified multiple factors (Serum lactate levels ˃ 2mmol/L, Organ failure, CT signs) that could suggest patients that require a surgical approach for ITIN.

ROLE OF LABORATORY METHODS IN INTEGRATED DIAGNOSTICS OF ACUTE MESENTERIAL ISCHEMIA

The aim of the review: to present literature data on the role of laboratory methods in the complex diagnosis of acute mesenteric ischemia. The main provisions. To search for scientific publications, we used the PubMed database, the RSCI, the Google Scholar search engine, as well as cited references. Articles relevant to the purpose of the review were selected for the period from 1999 to 2019 in the following terms: “acute mesenteric ischemia”, “pathogenesis”, “diagnosis”, “biomarkers”. Inclusion criteria were limited to acute arterial mesenteric ischemia. Acute mesenteric ischemia is an emergency condition caused by a sudden violation of the blood flow through the mesenteric vessels, which rapidly progresses to a heart attack of the intestinal wall and is accompanied by high mortality. Four main mechanisms of OMI are distinguished: embolism from the left parts of the heart or aorta, thrombosis of arteries or veins of the intestine, non-occlusive acute mesenteric ischemia (NOMI), due to vascular spasm. In this case, destructive disorders occur in the intestinal wall, starting from the mucous membrane to the serous, which leads to bacterial translocation and the development of a systemic inflammatory response syndrome. Early bowel revascularization is a key factor in reducing complications and mortality associated with it. However, in the initial stages of the disease has no specific signs, which complicate its diagnosis. The only way to detect mesenteric blood flow disorders is MSCT with angiography, and with non-occlusive lesions, mesenteric angiography, which in normal clinical practice is not always possible. Conclusion. It can be assumed that the use of laboratory methods will expand the range of diagnostic measures and will make it possible to conduct timely treatment aimed at restoring the mesenteric blood flow and improve the prognosis in patients with acute mesenteric ischemia.

Acute mesenteric ischaemia secondary to portal, splenic and superior mesenteric vein thrombosis

Mesenteric ischaemia represents an uncommon complication of splanchnic vein thrombosis which requires a high level of suspicion to diagnose in a timely manner. This report discusses a case of portal, splenic and superior mesenteric vein thrombosis leading to mesenteric ischaemia and infarct in a 79-year-old man. The diagnosis of acute mesenteric ischaemia and splanchnic vein thrombosis remains difficult due to the non-specific symptoms of these conditions. As diagnosis does continue to improve, treatment of acute mesenteric ischaemia using medical management has become increasingly possible before ischaemia advances to the point at which surgical resection is required.

Necessity of revascularization for acute mesenteric ischemia in symptomatic patients with spontaneous isolated dissection of the superior mesenteric artery

Objectives

We evaluated the necessity of revascularization for acute mesenteric ischemia in symptomatic patients with spontaneous isolated dissection of the superior mesenteric artery.

Methods

This retrospective study included 28 consecutive, symptomatic patients with spontaneous isolated dissection of the superior mesenteric artery treated at our hospital between December 2005 and December 2017. Patients with concomitant aortic dissection were excluded. We reviewed the patients’ clinical presentation; laboratory evaluations; computed tomography findings, including the true lumen residual ratio (i.e., the minimum true lumen size compared to the diameter of the transverse section of the dissected artery) at the time of admission; the number of patients who were suspected of having bowel ischemia; and the number of patients who required surgical or endovascular treatment and their outcomes. Additionally, to evaluate the true lumen residual ratio in symptomatic patients with bowel ischemia, the true lumen residual ratio in those with abnormal laboratory data were compared with that in those without abnormal laboratory data. Initial true lumen residual ratio values were also compared with final values. Furthermore, we assessed the clinical details of patients who had bowel necrosis. Categorical variables were compared using the χ2 test or Fisher’s exact test, and continuous values were presented as either the mean ± standard deviation or median (interquartile range 25–75%). Variables were analyzed using Student’s t-test or the Mann–Whitney U test.

Results

The patients’ age ranged between 41 and 85 years, and 25 were men. Although nine patients were suspected of having acute mesenteric ischemia, only one underwent bowel resection. None of the patients had an indication for revascularization. The true lumen residual ratio of the nine patients with abnormal laboratory data were significantly lower than those of the 19 without abnormal laboratory data (10 [0–25]% vs. 40 [20–50]%, p = 0.005). The patient who underwent bowel resection had a true lumen residual ratio of 10%; however, there was no obvious abnormal laboratory data suggestive of bowel necrosis. Dissections were managed conservatively in all patients. True lumen residual ratio increased from initial value of 30 (10–48)% to 98 (60-100)%at the final imaging study ( p < 0.0001). There were no adverse events related to the mesenteric circulation during the follow-up period of 2–11 years.

Conclusions

Reintervention is rarely required for spontaneous isolated dissection of the superior mesenteric artery, even in symptomatic patients, and spontaneous resolution of the luminal compromise is the rule.

Outcomes and clinical characteristics of transmural intestinal necrosis in acute mesenteric ischemia

Background: Acute mesenteric ischemia (AMI) is a rare life-threatening condition, especially for the patients with transmural intestinal necrosis (TIN). However, the optimal time for surgical intervention is controversial. As a series study, this study aimed to identify the outcomes and clinical characteristic of patients with TIN. Methods: Clinical data of 158 patients with AMI from January 2010 to December 2017 were retrospectively analyzed in a national gastrointestinal referral center in China to confirm the outcomes and identify predictors for TIN. Results: According to the results of pathological assessment and follow-up, 62 patients were TIN and 96 were non-TIN. Patients with TIN have a higher mortality and incidence of severe complications. The significant independent predictors for TIN were arterial lactate level (OR: 4.76 [2.29 ∼ 9.89]), free intraperitoneal fluid (OR: 9.49 [2.56 ∼ 35.24]) and pneumatosis intestinalis (OR: 7.08 [1.68 ∼ 29.82]) in computed tomography (CT) scan imaging. The overall area under the receiver operating characteristics (ROC) curve of the model was 0.934 (95% confidence interval: 0.893 ∼ 0.974). Using ROC curve, the cutoff value of arterial lactate level predicting the onset of TIN was 2.65 mmol/L. Conclusions: Patients concomitant with TIN manifest a higher risk of poor prognosis. The three predictors for TIN were arterial lactate level >2.65 mmol/L, free intraperitoneal fluid and pneumatosis intestinalis. Close monitoring these predictors would help identify AMI patients developed TIN and in urgent need for bowel resection.

Biochemical markers of acute intestinal ischemia: possibilities and limitations

Acute intestinal ischemia is a relative rare abdominal emergency, associated with considerably high morbidity and mortality rates. Although the conventional diagnostic approach to acute intestinal ischemia entails a preliminary evaluation of signs and symptoms, followed by radiological and laboratory investigations, a definitive diagnosis is can usually be made after laparotomy, which still remains the gold standard diagnostic (and therapeutic) procedure. Several potential laboratory biomarkers have been investigated over the past decades, but none of these seems to reach a suitable diagnostic accuracy for an early and reliable diagnosis of intestinal ischemia. The aim of this narrative review is to provide an overview on traditional laboratory tests for diagnosing acute intestinal ischemia (i.e., complete blood count, D-dimer, blood gas analysis, total lactic acid, C-reactive protein and procalcitonin), and summarize current evidence regarding some emerging and potentially useful biomarkers such as D-lactate, intestinal fatty acid-binding protein (I-FABP), ischemia modified albumin (IMA), α-glutathione S-transferase (α-GST), interleukin-6 (IL-6), citrulline and smooth muscle protein of 22 kDa (SM22). Among the various tests, D-lactate, IMA and I-FABP are perhaps the most promising, since they are characterized by optimal sensitivity and relatively good specificity, early kinetics, and can be measured with assays suited for a rapid diagnosis.