A modified endovascular technique for treating spontaneous isolated superior mesenteric artery dissection and the early to medium-term outcomes

Identifying acute mesenteric ischemia via mesenteric fractional flow reserve in patients with spontaneous isolated superior mesenteric artery dissection: case report

There is no definitive approach for assessing mesenteric ischemia and determining the optimal timing for endovascular intervention in the management of spontaneous isolated dissection of the superior mesenteric artery (SISMAD). A 56-year-old male with acute abdominal pain was diagnosed with SISMAD. After evaluating mesenteric ischemia through mesenteric fractional flow reserve (FFR), FFR was 0.72, and the patient was recommended conservative treatment for SISMAD, which involves fasting, total parenteral nutrition, and anticoagulation. The patient's syndrome was relieved after conservative treatment for 14 days without stent implantation. Over the next 5 years, no recurrence of abdominal pain or worsening of SISMAD was observed in the patient. Assessing the severity of mesenteric ischemia can be done through mesenteric FFR. Upon confirmation of the exclusion of risks related to dilatation or rupture of SISMAD aneurysm, an approach in favor of conservative management for SISMAD may indeed be considered pragmatic when the FFR exceeds 0.72.

Systematic review and meta-analysis of current evidence in endograft therapy for spontaneous isolated superior mesenteric artery dissection

The role of endovascular stent therapy (EST) in the treatment of spontaneous isolated superior mesenteric artery dissection (SISMAD) has gained momentum in recent years but remains controversial. We gathered research examining the advantages and disadvantages of EST for SISMAD patients. Primary outcomes involved both immediate and long-term results. Random or fixed effect models were used for effect size (ES) calculation with 95% confidence interval (CI) based on 50% heterogeneity threshold. Our analysis incorporated data from 21 studies including 611 SISMAD cases treated by EST. Our findings show a complication rate of approximately 1% following EST (95%CI 0.01-0.02, I2 = 0%, P = 0.97), with a bare minimum mortality rate of < 1% (95%CI 0.00-0.01, I2 = 0%, P > 0.05) and a reintervention rate of < 1% (95%CI 0.00-0.01, I2 = 0%, P = 0.89). We also found technique success and symptom resolution approaching 94% and 99%, respectively, in the immediate postoperative phase. In the long run, we observed a recurrence of symptoms at 3% (95%CI 0.00-0.06, I2 = 58.6%, P < 0.01), creation of new dissections at 1% (95%CI 0.00-0.02, I2 = 0%, P = 0.73), aneurysm progression at 2% (95%CI 0.00-0.03, I2 = 42.7%, P = 0.12), reintervention due to complications at 3% (95%CI 0.00-0.05, I2 = 0%, P = 0.43) and stenotic stents at 12% (95%CI 0.04-0.23, I2 = 77.5%, P < 0.01). Nevertheless, high levels of stent patency 98% (95% CI 0.97-1.00, I2 = 0%, P = 0.51) and complete remodeling 88% (95% CI 0.82-0.94, I2 = 65.5%, P < 0.05) were observed postoperatively. Overall, EST presents minimal complications and promising long-term outcomes for SISMAD, although the prevalence of stent stenosis requires further attention.

Midterm Results of the Conservative, Bare Stent, and Bare Stent-Assisted Coiling Treatments for Symptomatic Isolated Superior Mesenteric Artery Dissection

BACKGROUND

We compared the early and midterm (31, 3-63 months) outcomes of conservative treatment, bare stent treatment (BST), and bare stent-assisted coiling treatment (BSACT) to determine the most effective treatment for patients with symptomatic isolated superior mesenteric artery dissection (SISMAD).

METHODS

Consecutive patients with SISMAD admitted to the study hospital between January 2016 and December 2021 were included in this retrospective study. Their demographic data, clinical findings, treatment options, early outcomes, and follow-up results were analyzed.

RESULTS

A total of 121 patients were included in the study (23 with conservative treatment, 42 with BST, and 56 with BSACT). Symptoms were relieved in 91.3% of conservative patients, whereas all patients (100%) with BST or BSACT had symptom relief (P = 0.035). There was no significant difference in the length of hospital stay between the 2 endovascular treatments (P = 0.9051), but hospital stay was significantly shorter compared to conservative treatment (P < 0.0001). The cumulative rate of complete remodeling was 100% for BSACT versus 46.3% for BST (P < 0.0001) versus 42.9% for conservative patients (P < 0.0001). There were no significant differences between the last 2 groups (P = 0.3925). The prevalence of adverse events for abdominal pain recurrence and aneurysm formation was also significantly lower in the BSACT group at follow-up.

CONCLUSIONS

BSACT for SISMAD has a preferable early outcome. The cumulative complete remodeling rate and the event-free survival rate are satisfactory at midterm follow-up. BSACT is an effective approach for SISMAD.

Endovascular treatment of systematic isolated mesenteric artery dissection with a patent false lumen: Bare stents alone versus stent-assisted coiling

OBJECTIVES

Bare stent treatment and bare stent-assisted coiling treatment have not been directly compared in symptomatic isolated superior mesenteric artery dissection with a patent false lumen. Thus, we compared the early and mid-term outcomes of bare stent treatment and bare stent-assisted coiling treatment to determine the most effective remedy for patients with this condition.

METHODS

Consecutive patients diagnosed with systematic isolated superior mesenteric artery dissection with a patent false lumen admitted to the study hospital between January 2016 and December 2021 were enrolled in this retrospective study. Their demographic data, clinical findings, treatment options, early outcomes, and follow-up results were analyzed.

RESULTS

A total of 85 patients (83 men) were included. 34.1% (n = 29) adopted bare stent treatment and 65.9% (n = 56) underwent bare stent-assisted coiling treatment. The symptoms were relieved in all patients (100%) with bare stent treatment and bare stent-assisted coiling treatment. There was no significant difference in the length of hospital stay between the two endovascular treatments (p = 0.354). The cumulative complete remodeling rate was 100% in bare stent-assisted coiling treatment vs. 70.4% in bare stent treatment (p < 0.0001). The prevalence of adverse events for abdominal pain recurrence (none in BST or bare stent-assisted coiling treatment), and formation of the aneurysm (two in bare stent treatment, and none in bare stent-assisted coiling treatment) showed no significant difference at follow-up.

CONCLUSION

Both bare stent treatment and bare stent-assisted coiling treatment for symptomatic isolated superior mesenteric artery dissection with a patent false lumen have the same satisfying early outcome. In the midterm follow-up, bare stent-assisted coiling treatment has the higher cumulative complete remodeling rate which could be prioritized to treat this condition.

Natural Course and Treatment of Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection with Total True Lumen Occlusion

OBJECTIVE

We retrospectively investigated the association between the imaging features of spontaneous isolated superior mesenteric artery dissection (SISMAD) accompanied by total true lumen occlusion and the clinical symptoms to identify the patients at high risk and establish personalized therapeutic options.

METHODS

Among 261 patients with SISMAD, we selected 37 with Yun's type III dissection; 35 patients underwent successful conservative management and 2 patients underwent exploratory laparotomy. After discharge, all patients were periodically followed up on an outpatient basis. We recorded patients' general condition, symptoms, time until symptom relief, imaging findings and follow-up results.

RESULTS

All patients experienced acute abdominal pain prior to admission, with an onset time of 29.95 ± 24.66 hours. The mean time until relief of abdominal pain in patients who received conservative treatment was 42.17 ± 38.09 hours. Correlation analysis revealed no correlation between the length of dissection or of the occluded segment and abdominal pain intensity. Pain scores were lower and time until pain relief was shorter in patients with a definite arc of Riolan (AOR) on admission than in those without an AOR. No collateral circulation was observed in the two patients who underwent exploratory laparotomy, and distal intestinal perfusion was poor in these cases. Complete and partial remodeling of the superior mesenteric artery (SMA) was observed in 6 and 16 patients, respectively at the 12-month follow-up. Although the SMA remained occluded in 12 patients, abundant collateral circulation was detected. Three patients were lost to follow-up.

CONCLUSION

This study highlights that conservative treatment should be attempted as first-line therapy in most patients with Yun's type III SISMAD. Complete AOR can contribute to remission of clinical symptoms during the acute stage. Poor distal blood flow of occluded vessels may serve as an important indicator for identification of patients at high risk of ischemic intestinal necrosis.

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.

Endovascular Management of Isolated Superior Mesenteric Artery Dissecting Aneurysm by Retrograde Catheterization Via Collaterals from the Celiac Artery

Isolated superior mesenteric artery (SMA) dissecting aneurysm is frequently symptomatic and potentially catastrophic; thus, it usually requires endovascular treatment. The endovascular management can be challenging in certain cases as catheterization of the collapsed true lumen is often very difficult. This case report is to describe a new approach for catheterization of the true lumen of the SMA in a case of isolated SMA dissecting aneurysm. A 63-year-old male with an SMA dissecting aneurysm underwent stent-graft placement for treatment. Catheterization of the true lumen via the anterograde approach was unsuccessful because of angulation and collapse of the SMA true lumen as a result of the dissecting aneurysm. A guidewire was passed through the collaterals from the celiac artery and retrogradely passed across the collapsed SMA true lumen into the aorta. We then used a snare that had been delivered through the contralateral femoral access to capture and retrieve the guidewire. A delivery system was advanced into the SMA, and a stent graft was successfully deployed to occlude the dissecting aneurysm. This report introduces a new feasible retrograde approach that provides access to the SMA true lumen via celiac collaterals in cases of difficult antegrade catheterization of an SMA dissecting aneurysm.

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.