Endovascular Treatment of Patients with Isolated Mesenteric Artery Dissection Aneurysm: Bare Stents Alone Versus Stent Assisted Coiling

Systematic review and meta-analysis of current evidences in endograft therapy vs. medical treatment for Spontaneous Isolated Superior Mesenteric Artery Dissection

OBJECTIVE

Endovascular stent therapy (EST) for spontaneous isolated superior mesenteric artery dissection (SISMAD) is gaining popularity, yet the treatment strategy - BMT or EST - remains debatable.

METHODS

A meta-analysis examined all randomized trials and observational studies exploring the relative merits and potential risks of EST vs. BMT in treating SISMAD patients. Key outcomes included early and long-term adverse effects, with odds ratios (ORs) and 95% confidence intervals (CI) calculated. A random- or fixed-effects model was selected according to a 50% heterogeneity threshold.

RESULTS

9 observational studies involving a total of 672 SISMAD patients (303 EST), met our selection criteria. We discovered no noteworthy distinctions between the EST group and the BMT group in terms of early symptoms' alleviation, reinterventions, or all-cause mortality. However, patients receiving EST management will be hospitalized longer than those receiving BMT (EST: 13.2 ± 5.1 months vs. BMT: 7.0 ± 2.2 months, P < 0.01). In the long run, EST was found to significantly contribute to a higher rate of complete remodeling (OR: 4.53, CI: 3.01 ~ 6.81, P < 0.01; heterogeneity, I2 = 50%) and a lower incidence of aneurysm formation (OR: 0.19, CI: 0.06 ~ 0.6, P < 0.01; heterogeneity, I2 = 0%) than BMT. However, there are no significant differences between ESTand BMTin terms of all-cause mortality, recurrent syndrome, reintervention, and SMA stenosis or occlusion.

CONCLUSION

EST can effectively prevent the formation of aneurysmal dissection and improve SISMAD remodeling. Both EST and BMT are similar in reducing long-term mortality, recurrent symptoms, severe SMA stenosis or occlusion, and the need for reintervention in patients with SISMAD.

In-stent Restenosis After Stenting for Superior Mesenteric Artery Dissection Is Associated With Stent Landing Zone: From Clinical Prediction to Hemodynamic Mechanisms

OBJECTIVE

To identify risk factors for in-stent restenosis (ISR) in patients undergoing stent placement for superior mesenteric artery dissection (SMAD) and to determine the hemodynamic mechanism underlying ISR.

METHODS

For this retrospective study, patients with SMAD who had ISR after stent placement were included in the ISR group, and age- and sex-matched patients with SMAD who did not experience ISR after stent placement were included in the control group. Clinical, imaging, and hemodynamic data were assessed. Multivariable regression was used to identify independent ISR risk factors. Structural and fluid dynamics simulations were applied to determine the hemodynamic mechanism underlying the occurrence of ISR.

RESULTS

The study population included 26 patients with ISR and 26 control patients. Multivariate analysis demonstrated that stent-to-vascular (S/V) ratio (odds ratio [OR], 1.14; 95% confidence interval [CI]: 1.00-1.29; p=0.045), stent proximal position >10 mm away from the SMA root (OR, 108.67; 95% CI: 3.09-3816.42; p=0.010), and high oscillatory shear index (OSI) area (OR, 1.25; 95% CI: 1.02-1.52; p=0.029) were predictors of ISR. In structural and fluid dynamics simulations, a stent proximal position near the abdominal aorta (AA) or entering into the AA reduced the contact area between the proximal struts of the stent and the vascular wall, and alleviated the distal lumen overdilation.

CONCLUSION

The S/V ratio, stent proximal position away from the SMA root (>10 mm), and high OSI area are independent risk factors for ISR in patients with SMAD undergoing stent placement. Deploying the proximal end of the stent near the AA or entering into the AA appears to improve the hemodynamic environment in the SMA lumen and ultimately reduce the risk of ISR.

CLINICAL IMPACT

In-stent restenosis is an uncommon but potentially catastrophic complication after stent placement for the management of superior mesenteric artery dissection. This study identified risk factors for in-stent restenosis and demonstrated that, as long as the stent can fully cover the dissection range, deploying the proximal end of the stent near the abdominal aorta or less entering into the abdominal aorta may reduce the risk of in-stent restenosis in this patient population.

Guidelines on the diagnosis, treatment and management of visceral and renal arteries aneurysms: a joint assessment by the Italian Societies of Vascular and Endovascular Surgery (SICVE) and Medical and Interventional Radiology (SIRM)

The objective of these Guidelines is to provide recommendations for the classification, indication, treatment and management of patients suffering from aneurysmal pathology of the visceral and renal arteries. The methodology applied was the GRADE-SIGN version, and followed the instructions of the AGREE quality of reporting checklist. Clinical questions, structured according to the PICO (Population, Intervention, Comparator, Outcome) model, were formulated, and systematic literature reviews were carried out according to them. Selected articles were evaluated through specific methodological checklists. Considered Judgments were compiled for each clinical question in which the characteristics of the body of available evidence were evaluated in order to establish recommendations. Overall, 79 clinical practice recommendations were proposed. Indications for treatment and therapeutic options were discussed for each arterial district, as well as follow-up and medical management, in both candidate patients for conservative therapy and patients who underwent treatment. The recommendations provided by these guidelines simplify and improve decision-making processes and diagnostic-therapeutic pathways of patients with visceral and renal arteries aneurysms. Their widespread use is recommended.

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

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

Acute Isolated Mesenteric Artery Dissection: Four Year Experience From a French Intestinal Stroke Centre

OBJECTIVE

This study aimed to report outcomes of patients with symptomatic acute isolated mesenteric artery dissection (IMAD) treated within a French intestinal stroke centre (ISC).

METHODS

All patients with symptomatic IMAD referred to the ISC from January 2016 to January 2020 were included prospectively. Patients with aortic dissection and asymptomatic IMAD were not included. The standardised medical protocol included anticoagulation and antiplatelet therapy, gastrointestinal resting, and oral antibiotics. Operations were considered for acute mesenteric ischaemia (AMI).

RESULTS

Among the 453 patients admitted to an ISC during the study period, 34 (median age, 53 years [41 - 67]; 82% men) with acute symptomatic IMAD were included. According to the classification of Yun et al., IMADs were reported as follows: type I (n = 7, 20%), type IIa (n = 6, 18%), type IIb (n = 15, 44%), and type III (i.e., complete superior mesenteric artery [SMA] occlusion; n = 6, 18%). Overall, nine (26%) patients had AMI (type I/II, n = 3; type III, n = 6). On initial computerised tomography angiogram, nine (26%) patients had an associated visceral arterial dissection or pseudoaneurysm. All patients with types I/II (n = 28, 82%) followed a favourable clinical course with conservative therapy, with no need for any operation. All patients with type III (n = 6, 18%) underwent urgent laparotomy with SMA revascularisation (open, n = 4; stenting, n = 1) and or bowel resection (early, n = 3; late, n = 1). Rates of intestinal resection and short bowel syndrome were 12% and 8.8%, respectively. After a median follow up of 26 months [18 - 42], recurrence of symptoms occurred in four (12%) patients and aneurysmal change in 14 (41%), with no re-intervention.

CONCLUSION

Although IMAD was associated with a high frequency of AMI, a standardised protocol produced a low rate of intestinal resection. Conservative therapy seems appropriate in types I/II patients, whereas urgent SMA revascularisation should aim to avoid intestinal resection or death in type III patients.

The pathogenesis of superior mesenteric artery dissection: An in-depth study based on fluid-structure interaction and histology analysis

OBJECTIVE

To explore the role of hemodynamic factors in the occurrence of superior mesenteric artery (SMA) dissection (SMAD) using a fluid-structure interaction (FSI) simulation method, and to identify histopathologic changes occurring in the wall of the SMA.

METHODS

A total of 122 consecutive patients diagnosed with SMAD and 122 controls were included in this study. Hemodynamic factors were calculated using a FSI simulation method. Additionally, SMA specimens obtained from 12 cadavers were stained for histological quantitative analysis.

RESULTS

The mean aortomesenteric angle (59.7° ± 21.4° vs 48.2° ± 16.8°; p < .001) and SMA maximum curvature (0.084 ± 0.078 mm^-1 vs 0.032 ± 0.023 mm^-1; p < .001) were higher in SMAD patients than the controls. Larger aortomesenteric angles and SMA curvatures were associated with higher and more concentrated wall shear stress at anterior wall of the SMA curve segment, co-located with the dissection origins. The mean thickness of media (325.18 ± 44.87 µm vs 556.92 ± 138.32 µm; p = .003) was thinner in the anterior wall of the SMA curve than in the posterior wall. The area fractions of elastin (17.96% ± 3.36% vs 27.06% ± 4.18%; p = .002) and collagen (45.43% ± 6.89% vs 55.57% ± 7.57%; p = .036) were lower in anterior wall of the SMA curve than in posterior wall.

CONCLUSION

Increased aortomesenteric angle and SMA curvature are risk factors for SMAD. Both of these factors can cause local hemodynamic abnormalities, which can lead to histopathologic changes in anterior wall of SMA.

Endovascular therapy versus medical treatment for spontaneous isolated dissection of the superior mesenteric artery

BACKGROUND

Spontaneous isolated dissection of the superior mesenteric artery (SIDSMA) occurs when a tear in the inner layer of the superior mesenteric artery (SMA) allows blood to flow between the layers of the SMA, forcing the layers apart, and creating two lumens. Abdominal pain is the most prevalent clinical manifestation. Other people may have no symptoms or experience nausea, vomiting, diarrhea, or blood in their stools. For people with SIDSMA who are not suspected of intestinal necrosis or intra-abdominal bleeding, medical treatment and endovascular therapy are the main treatment options. There is no consensus on the optimum first-line management strategy.

OBJECTIVES

To evaluate the benefits and harms of endovascular therapy versus medical treatment for spontaneous isolated dissection of the superior mesenteric artery (SIDSMA).

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 3 August 2021.

SELECTION CRITERIA

We planned to include all randomized controlled trials (RCTs) which compared endovascular therapy and medical treatments for SIDSMA. We planned to exclude studies where participants were treated with open surgery.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were endovascular intervention rate and recurrent abdominal pain. Our secondary outcomes were open surgery rate, remodeling rate of SMA, new aneurysm formation of SMA, SMA occlusion, new dissection of SMA, death, symptom relief rate and complications of endovascular therapy. We planned to use GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We did not identify any RCTs to include in any analysis.

AUTHORS' CONCLUSIONS

We were not able to include any RCTs that compared endovascular therapy versus medical treatment in people with SIDSMA. High-quality RCTs that evaluate the benefits and harms of these interventions are needed to help determine the optimal strategy for managing SIDSMA.

Long-term outcome of spontaneous isolated superior mesenteric artery dissection in different angiographic types

OBJECTIVE

This study aimed to compare the follow-up and outcomes of spontaneous isolated superior mesenteric artery dissection (SISMAD) in different angiographic types and to determine the optimal therapeutic options for SISMAD patients.

METHODS

This is a retrospective study of 61 SISMAD patients between December 2010 and January 2019 in a single center. Data analysis consisted of demographics, clinical data, radiology review, treatment, follow-up, and outcomes.

RESULTS

A total of 61 SISMAD patients were reviewed in this study. Median age was 53 (quartile, 47.5-63.0), 90.2% were males with hypertension (50.8%), dyslipidaemia (54.1%), and smoking history (60.7%). Among all, 43 patients underwent periodic follow-up of computed tomography (CT) angiography for follow-up analysis. 11 (25.6%) patients showed "No Change" during follow-up, including 6 type I patients. 23 patients (53.5%) were "Partially Remodelled" and 18 of them were type II patients. 7 "Completely Remodelled" patients (16.3%) were all in type II group. Two type III patients (4.6%) died after the emergent surgical intervention within 30 days.

CONCLUSIONS

Different SISMAD angiographic types present with variant progression. Type I SISMAD may be inclined to remain "unchanged." Type II SISMAD shows a clear trend to remodeling, especially type IIb patients. The progression of type III SISMAD varies in the extent of collateral bypasses.

Management of Spontaneous Isolated Mesenteric Artery Dissection: A Systematic Review

Background and Aims:

There are increasing reports on case series on spontaneous isolated mesenteric artery dissection, that is, dissections of the superior mesenteric artery and celiac artery, mainly due to improved diagnostic capacity of high-resolution computed tomography angiography performed around the clock. A few case–control studies are now available, while randomized controlled trials are awaited.

Material and Methods:

The present systematic review based on 97 original studies offers a comprehensive overview on risk factors, management, conservative therapy, morphological modeling of dissection, and prognosis.

Results and Conclusions:

Male gender, hypertension, and smoking are risk factors for isolated mesenteric artery dissection, while the frequency of diabetes mellitus is reported to be low. Large aortomesenteric angle has also been considered to be a factor for superior mesenteric artery dissection. The overwhelming majority of patients can be conservatively treated without the need of endovascular or open operations. Conservative therapy consists of blood pressure lowering therapy, analgesics, and initial bowel rest, whereas there is no support for antithrombotic agents. Complete remodeling of the dissection after conservative therapy was found in 43% at mid-term follow-up. One absolute indication for surgery and endovascular stenting of the superior mesenteric artery is development of peritonitis due to bowel infarction, which occurs in 2.1% of superior mesenteric artery dissections and none in celiac artery dissections. The most documented end-organ infarction in celiac artery dissections is splenic infarctions, which occurs in 11.2%, and is a condition that should be treated conservatively. The frequency of ruptured pseudoaneurysm in the superior mesenteric artery and celiac artery dissection is very rare, 0.4%, and none of these patients were in shock at presentation. Endovascular therapy with covered stents should be considered in these patients.

Safety and efficacy of conservative, endovascular bare stent and endovascular coil assisting bare stent treatments for patients diagnosed with spontaneous isolated superior mesenteric artery dissection

Introduction

Isolated dissection of visceral artery organs is very infrequently reported and when it occurs it mostly affects the superior mesenteric artery (SMA) with abdominal pain as the commonest presenting symptom. However, the best therapeutic strategy in symptomatic patients has not yet been established.

Aim

To evaluate the safety and efficacy of conservative, endovascular bare stent and endovascular coil assisting bare stent treatments for patients diagnosed with spontaneous isolated superior mesenteric artery dissection (SISMAD).

Material and methods

We reviewed patients who had SISMAD and received conservative, bare stent and coil assisting bare stent as a primary treatment between 2014 and 2018. Patient demographics, symptoms, angiographic findings and treatment outcomes were analyzed.

Results

A total of 62 patients was found to have SISMAD among whom 83.9% (n = 52) were male and 16% (n = 10) were female with the mean age of 52.55 ±7.22 years, range 33–77. 22.6% (n = 14) received conservative, 62.9% (n = 39) endovascular bare stent and 14. Four percent (n = 9) endovascular coil assisting bare stent treatment. The success rate in primary treatment was conservative 78.5% (n = 11), bare stent 97.4% (n = 38), coil assisting bare stent 100% (n = 9). The mean follow-up duration (months) was 28.76 ±12.87.

Conclusions

Endovascular bare stent placement is a safe, effective, and successful treatment in the management of symptomatic SISMAD. The diagnostic imaging result is a key point for planning appropriate treatment especially in patients with tapered vessels, longer dissection lesion, and dissection aneurysm where coil assisting bare stent shows good results. Conservative treatment should be given priority for the asymptomatic patient, but close monitoring is highly recommended.

Primary Conservative Therapy for Symptomatic Isolated Mesenteric Artery Dissection with Severely Compressed True Lumen or Large Dissecting Aneurysm

PURPOSE

To investigate the safety and effectiveness of primary conservative therapy for patients with symptomatic isolated mesenteric artery dissection (IMAD) with a severely compressed true lumen and/or a large dissecting aneurysm.

MATERIALS AND METHODS

A total of 35 consecutive patients (all men; median age, 53 y) with symptomatic IMAD with a severely compressed true lumen and/or a large dissecting aneurysm but without intestinal necrosis or arterial rupture who were treated with primary conservative therapy between November 2018 and February 2020 were assessed. A severely compressed true lumen was defined as luminal stenosis > 70%. A large dissecting aneurysm was defined as dissecting aneurysm diameter ≥ 1.5 times larger than the normal mesenteric artery diameter.

RESULTS

There was a strong positive relationship among abdominal pain, degree of luminal stenosis, and length of dissection (R = 0.811; P < .001). Conservative treatment was successful in all patients. Abdominal pain was eliminated within 4.7 d ± 4.8 (range, 2-31 d) in all patients, within 3.6 d ± 1.2 (range, 2-6) in the 31 patients with minor or moderate abdominal pain, and within 13.3 d ± 11.9 (range, 6-31 d) in the 4 patients with severe abdominal pain. Complete or partial remodeling of the mesenteric artery was achieved in 6 (17.1%) and 29 (82.9%) patients, respectively, during 8.6 mo ± 4.3 of follow-up.

CONCLUSIONS

Primary conservative therapy can be used safely and effectively in patients with symptomatic IMAD with a severely compressed true lumen and/or a large dissecting aneurysm but without intestinal necrosis or arterial rupture.

Management of Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection: A Single Centre Experience with Mid Term Follow Up

OBJECTIVE

This study aimed to report a single centre management experience and mid term outcomes for symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD).

METHODS

This was a retrospective observational study. Between 1 August 2012, and 30 June 2018, consecutive patients with symptomatic SISMAD were included. Patient demographics, clinical symptoms, comorbidities, risk factors, and dissection characteristics were obtained. The treatment regimens and clinical and follow up outcomes were reviewed and analysed. A chi square test, Fisher's exact test, or one way analysis of variance was used to compare variables between the groups. Binary logistic regression was used to determine predictive factors for failed conservative treatment. The cumulative rate of complete dissection remodelling was calculated using a Kaplan-Meier curve.

RESULTS

Sixty-two patients (mean age, 56.0 ± 9.3 years) were included. Patients at risk of intestinal ischaemia or dissecting aneurysm rupture were considered to be high risk patients (Group 1, n = 16) and received primary endovascular treatment. The remaining patients were considered low risk (Group 2, n = 46) and received primary conservative treatment. Symptom relief was observed in 82.6% of patients in Group 2. Finally, failed conservative treatment was observed in 50% of the low risk patients. Dissection length ≥50 mm was an independent risk factor for failed conservative treatment (p = .019; OR 4.68, 95% CI 1.29-16.98). During a median follow up of 30.5 months (interquartile range, 17.5, 58.3), patients with stents had a higher complete dissection remodelling rate than those without stents.

CONCLUSION

This study found that conservative treatment showed satisfactory symptom resolution for low risk SISMAD patients. Endovascular stenting was associated with a high technical success and dissection remodelling rate. This treatment modality might be reserved for patients with high risk SISMAD or failed conservative treatment. In addition, a dissection length ≥50 mm was a risk factor for failed conservative treatment.

The impact of endovascular treatment on clinical outcomes of stable symptomatic patients with spontaneous superior mesenteric artery dissection

OBJECTIVE

To evaluate the efficacy and clinical outcomes of endovascular treatment for superior mesenteric artery dissection (SMAD) and its effect on superior mesenteric artery (SMA) remodeling compared with medical management alone after successful initial medical management.

METHODS

In this retrospective analysis, all patients with spontaneous SMAD at a single institution were identified from March 2007 to August 2019. The primary outcomes were freedom from major adverse events (MAEs, a composite of dissection-related death, the recurrence of mesenteric ischemia symptoms, and a requirement for intervention). The secondary outcomes were morphologic remodeling of the dissections and stenosis or occlusion of the SMA.

RESULTS

A total of 94 patients with SMAD who underwent successful initial medical management (91 males; mean age, 50.4 ± 6.3 years) were enrolled in the study. Fifty-seven (60.6%) received medical management alone, and 37 (39.4%) underwent endovascular repair after initial medical management. In the endovascular group, the technical success rate was 86.5% (32 of 37). During a mean follow-up period of 33.6 ± 26.2 months (range, 1-120 months), nine (9.6%) patients experienced a recurrence of abdominal pain, and six had additional interventions for SMAD. The patients in the endovascular group showed more complete or partial remodeling (22 [81.1%] vs 24 [44.4%]; P < .0001) or unchanged dissections (5 [13.5%] vs 23 [42.6%]; P = .0001) than those in the conservative group. Survival analysis showed that the estimated MAE-free survival rates were 95.6%, 88.9%, and 85.4% at 1, 3, and 5 years, respectively. There was a higher freedom from SMA stenosis or occlusion in the endovascular group (log rank P = .046).

CONCLUSIONS

Endovascular treatment and medical management alone result in similar MAE-free survival for patients with SMAD after successful initial medical management. Moreover, endovascular therapy is associated with a higher complete remodeling rate and greater freedom from SMA stenosis or occlusion.

Mid-term outcomes of symptomatic isolated superior mesenteric artery dissection with endovascular management

OBJECTIVES

The clinical outcomes, safety, and efficacy of endovascular management are explored for symptomatic isolated superior mesenteric artery dissection (ISMAD).

METHODS

In this retrospective study, 51 consecutive patients with symptomatic ISMAD received endovascular management from three institutions between January 2011 and December 2019.These patients were categorized into group A (endovascular treatment was used as the first-line therapy) and group B(endovascular treatment was used as the second-line therapy). The general epidemiological data, clinical manifestations, first-episode symptoms, treatment process, imaging findings, follow-up outcomes were analyzed from the medical records.

RESULTS

A total of 51 patients with endovascular management were collected in this study. Significant differences were observed between the two groups with respect to the course (150 h vs. 57 h; p < 0.001), intestinal ischemia (26.32% vs. 6,25%; p = 0.04) and dissection length (45.26 ± 13.78 mm vs. 63.37 ± 12.73 mm; p < 0.001). Technical success rate was 90.2% (46/51). There was significant difference in the MOD (42.27 ± 23.41 min vs. 76.63 ± 28.62 min p < 0.001), MPSRT (4.67 ± 2.65 h vs. 7.32 ± 2.49 h, p = 0.02), LOS (9.52 ± 3.72 days vs. 11.86 ± 4.13 days; p = 0.01) between the two groups. The bleeding complication rate was 7.84% (one patient in group A and three patients in group B). A total of 48 (94.12%, 48/51) patients were followed up for a median of 36.51 months (range, 4-87 months). Positive events of the SMA were achieved in 81.25% (39/48), and negative events of the SMA were achieved in 18.75% (8/48) based on the follow-up contrast-enhanced CT scan.

CONCLUSIONS

Endovascular management of symptomatic ISMAD has a high technical success rate and efficient at controlling symptoms. Furthermore, as more positive events occur, endovascular management should be encouraged early when pain persists after conservative management or there are signs of disease progression.

Long-term outcomes of conservative treatment and endovascular treatment in patients with symptomatic spontaneous isolated superior mesenteric artery dissection: a single-center experience

BACKGROUND

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

METHODS

Forty-two consecutive SISMAD patients who were admitted to a single center between October 2009 and May 2018 were enrolled in this study. Based on their symptoms, 15 had conservative treatment, and 27 had endovascular treatment. The baseline characteristics, treatments, and follow-up results of the conservative group and endovascular group were analysed.

RESULTS

The rates of symptom relief were 93.3% in the conservative group and 96.3% in the endovascular group. The procedure-related complications in the endovascular group included one case of pseudoaneurysm formation in the left brachial artery. During the follow-up period (median 28.5 months), a higher proportion of patients in the conservative group had symptom recurrence (42.9% in the conservative group versus 4.8% in the endovascular group, p < 0.001). Four patients in the conservative group and one patient in the endovascular group had additional endovascular intervention during follow-up. Compared with the conservative group, patients in the endovascular group had statistically significantly longer symptom-free survival (p = 0.014) and a higher rate of superior mesenteric artery (SMA) remodeling (p < 0.001).

CONCLUSIONS

For symptomatic SISMAD, endovascularly treated patients had a lower rate of symptom recurrence and a higher rate of SMA remodeling in the long term. Prospective, multi-center studies are needed to confirm the long-term outcomes of both treatments.

Management Strategy Based on Disease Stages for Patients with Symptomatic Isolated Mesenteric Artery Dissection

BACKGROUND

An optimal treatment regimen is sought for symptomatic isolated mesenteric artery dissection (IMAD) on the basis of its clinical staging.

METHODS

From January 2011 to December 2018, 120 patients with symptomatic IMAD from two institutions were collected retrospectively. We reviewed the clinical features, risk factors, computed tomography (CT) images, treatment modalities, and follow-up results to propose a new management strategy based on the clinical stages of the disease.

RESULTS

A total of 120 patients were collected in this study; 77 patients (69 men, 8 women; median age, 52.53 years; range, 39-73 years) who had undergone successful conservative management with antithrombotic agents were included in group A. The remaining 43 patients (34 men, 9 women; median age, 52.63 years; range, 26-66 years) who underwent invasive therapy were included in group B. Significant differences were observed between the two groups with respect to dissection length (50.72 ± 27.72 mm vs. 62 ± 24.3 mm; P = 0.02), true lumen residual diameter (3.31 ± 1.05 mm vs. 2.83 ± 2.05 mm; P = 0.01), and branch involvement (8 and 19, respectively; P < 0.001). Success was achieved in 76.24% (77/101) of patients treated by conservative management with antithrombotic agents in the acute stage; 43 patients underwent invasive interventional therapy in different stages of symptomatic IMAD. In group A, 6 patients had recurrent abdominal pain, three of whom underwent invasive intervention, and the remaining patients improved after conservative treatment. Positive remodeling was observed in 80.33% (49/61) of patients treated with conservative management alone versus 19.67% (12/61) of patients who experienced negative remodeling. Endovascular intervention in group B, CT angiography, or mesenteric angiography yielded complete remodeling in 23 (76.67%, 23/30) patients and evidence of stent restenosis in 7 (23.33%, 7/30) patients. Among the surgical patients, 7 patients showed improvement in the luminal diameter. However, 3 patients with short bowel syndrome require long-term parenteral nutrition.

CONCLUSIONS

Conservative management with antithrombotic agents should be a first-line regimen for symptomatic IMAD in the acute stage. If symptoms persist, endovascular intervention is a safe and feasible treatment in the subacute or chronic stage. When peritonitis is present, surgical treatment should be promptly performed, regardless of the disease stage.

Combination of Colour Duplex and Contrast Enhanced Ultrasound as an Alternative to Computed Tomography Angiography in Isolated Mesenteric Artery Dissection Surveillance

OBJECTIVES

The aim was to investigate the effectiveness of colour duplex ultrasound (CDU) plus contrast enhanced ultrasound (CEUS) vs. computed tomography angiography (CTA) for surveillance in patients with isolated mesenteric artery dissection (IMAD).

METHODS

Patients who underwent CDU, CEUS, and CTA for surveillance of IMAD between January 2012 and May 2019 were included in the study. The accuracy of CDU, CEUS, and CTA for determining the morphological characteristics of IMAD was analysed.

RESULTS

A total of 42 patients undergoing 76 total imaging examinations during follow up were included. Both CTA and CDU plus CEUS demonstrated the thrombosed false lumen for 28 (36.8%) examinations and the dissecting aneurysm for 20 (26.3%) examinations (both κ = 1.0). The diameter of the dissecting aneurysm was 5.03 ± 1.25 mm using CDU and CEUS vs. 5.27 ± 1.23 mm on CTA (coefficient of consistency, 0.997; p < .001). The entry points were visualised by CDU and CEUS for 20 (26.3%) examinations and by CTA for 14 (18.4%) examinations (κ = 0.769); no re-entry points were visualised by CDU and CEUS for any examinations but re-entry points were visualised by CTA for two (2.6%) examinations. The minimum inner diameter was 2.80 ± 1.30 mm on CDU and CEUS vs. 2.52 ± 1.29 mm on CTA (coefficient of consistency, 0.999; p < .001). The peak systolic velocities were 128.2 ± 13.0 cm/s at diagnosis and 98.7 ± 4.9 cm/s after one month (p < .001).

CONCLUSIONS

The combination of CDU and CEUS can be used in place of CTA for the surveillance of IMAD.

Mesenteric Artery Remodeling after Conservative Management in Patients with Isolated Mesenteric Artery Dissection

PURPOSE

To retrospectively investigate factors associated with mesenteric artery remodeling after conservative management of isolated mesenteric artery dissection (IMAD) (dissection of the mesenteric arteries in the absence of aortic dissection or other known causes).

MATERIALS AND METHODS

A total of 107 patients diagnosed with IMAD between February 2010 and October 2018 were identified. Eighteen patients were excluded because they underwent stent placement (n = 11) or were lost to follow-up (n = 7). A total of 89 patients who underwent conservative management were therefore included in the study. Cox regression analysis was performed to identify factors associated with mesenteric artery remodeling.

RESULTS

During 15.9 ± 10.9 months of follow-up, complete remodeling of the mesenteric artery was achieved in 66 patients (74.2%), and partial remodeling was achieved in 23 patients (25.8%). Of the 66 patients with complete remodeling, 6 (9.1%) had type IIa IMAD (visible false lumen, no visible re-entry site), and 60 (90.9%) had type IIb IMAD (thrombosed false lumen). The mean interval between IMAD diagnosis and complete remodeling was 14.4 ± 5.4 months for all patients. The mean intervals for patients with type IIa IMAD were 20.0 ± 6.2 months and 13.9 ± 5.1 months for patients with type IIb IMAD (P = .015). Mesenteric artery remodeling was significantly associated with the presence of symptoms (odds ratio, 10.800; 95% confidence interval, 1.961-59.470; P = .006).

CONCLUSIONS

Complete remodeling of the mesenteric artery in patients with IMAD treated with conservative management is common, and the presence of symptoms is associated with complete remodeling.

Factors Associated with Failed Conservative Management in Symptomatic Isolated Mesenteric Artery Dissection

OBJECTIVE

The aim of this study was to assess factors associated with conservative management failure in patients with symptomatic isolated mesenteric artery dissection.

METHODS

Patients with symptomatic isolated mesenteric artery dissection who underwent conservative therapy as first line treatment between February 2010 and May 2018 were included in this retrospective study. Conservative management failure was defined as the persistence or aggravation of symptoms and signs, increasing aneurysmal dilation, or new appearance of a dissecting aneurysm after conservative management. Univariable and multivariable analyses were performed to identify risk factors for failure of conservative management.

RESULTS

A total of 123 patients (115 men, 8 women, mean age, 53.7 ± 6.1 years) were included in this study. Conservative management was successful in 89 (72.4%) patients but failed in the remaining 34 (27.6%) patients. Of the 89 for whom conservative management was successful, all of the symptoms were eliminated (n = 81) or relieved (n = 8) within 3.8 ± 0.7 days after conservative management. All of the 34 patients in whom conservative management failed underwent successful endovascular stenting. Failure of conservative management was associated with type II IMADs as defined by the Sakamoto classification (meaning that there is an entry tear, but no re-entry, and still no thrombosis of false lumen, odds ratio: 33.76; 95% confidence interval 8.65-131.85; p < .001) and with ≥90% luminal stenosis (odds ratio 40.70; 95% confidence interval: 3.76-440.07; p < .01).

CONCLUSIONS

Conservative management can be used successfully in most patients with symptomatic isolated mesenteric artery dissection. Risk factors for failed conservative treatment were type II IMADs and degree of luminal stenosis ≥90%.

Endovascular Repair of a Complex Isolated Dissecting Aneurysm of the Superior Mesenteric Artery

Introduction

Isolated dissection of the superior mesenteric artery (SMA) is rare and remains the most common reason for aneurysmal degeneration of the vessel. The treatment is challenging and not standardised. The purpose of this report is to demonstrate that coiling of the false lumen is a good alternative for dissecting SMA aneurysms.

Report

A 50 year old male presented with a 3.3 cm dissecting aneurysm of the SMA and epigastric pain of moderate severity. More than 50% of the ileal arteries arose from the collapsed true lumen. Via transfemoral access the true lumen was catheterised. An open cell balloon expandable stent was deployed at the proximal and a closed cell self expandable stent at the distal end of the dissection flap. Through the cells of the first stent a microcatheter was advanced into the false lumen and 33 coils were deployed into the aneurysm sac. A stent graft was deployed within the first stent leading to the total exclusion of the aneurysm. Follow up at three months was uneventful and the patency was assessed by contrast enhanced ultrasound.

Discussion

Coiling of the false aneurysm is a good alternative for dissecting SMA aneurysms, where no other open surgical or endovascular options are applicable.

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Spontaneous isolated SMA dissection is the most frequent type of visceral artery dissection.

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Spontaneous isolated SMA dissection is the most frequent cause of SMA dissecting aneurysms.

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Treatment of SMA dissecting aneurysms remains controversial.

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Coiling of the false lumen and stenting of the true lumen is an effective method of treatment.