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 Bare Stenting for Isolated Superior Mesenteric Artery Dissection

Purpose:

To investigate the clinical outcomes of endovascular bare stenting in patients with symptomatic isolated superior mesenteric artery (SMA) dissection (ISMAD).

Methods:

This study was a retrospective analysis which included a total of 9 patients with symptomatic ISMAD (7 males and 2 females, age range: 48-67 years) who were treated with endovascular bare stenting. Data regarding basic patient clinical characteristics, e-technical success of the operation, and long-term patient outcomes were assessed.

Results:

Endovascular bare stenting was found to be technically successful in all patients. A total of 9 stents were inserted in these 9 patients. Five patients presented with stable false lumen and 4 patients presented with shrinking of false lumen after stenting. Both the trunk and branches of the SMA remained patent in all patients after stent insertion. There was no incidence of procedure-related complications, with all patients experiencing progressive symptom relief and subsequent symptom abatement within 1 week of the operation. Over a median 24 month follow-up period (range: 12-36 months), abdominal computed tomographic angiography revealed that all patients had obliterated dissections. In addition, there were no instances of stent obstruction, intestinal necrosis, or antiplatelet related bleeding during the follow-up period.

Conclusions:

Endovascular bare stenting was found to be a safe and effective treatment for patients with ISMAD.

Spontaneous isolated superior mesenteric artery dissection: Systematic review and meta-analysis

OBJECTIVES

Spontaneous isolated superior mesenteric artery dissection (SISMAD) is a rare disease with an incidence of 0.06%. The purpose of the meta-analysis was to identify the outcomes associated with the various treatment options in the management of asymptomatic and symptomatic patients with SISMAD.

METHODS

Eligible studies were selected by searching PubMed, EMBASE, and Cochrane Library. Endpoints were outcome of asymptomatic patients treated conservatively, resolution of symptoms according to the treatment approach, rate of symptomatic patients switched from conservative to the endovascular and/or open repair, characteristics of the dissected lesion, and findings regarding the remodeling of superior mesenteric artery.

RESULTS

We identified 30 studies including 729 patients. Among them, 608 (83.4%) were symptomatic and were managed with conservative (438/72%), and/or endovascular (139/22.8%) and/or open treatment (31/5%). The remaining were asymptomatic and they were treated solely conservatively. A high rate of resolution of symptoms (92.8%) was noted for patients treated conservatively. Conversion from conservative treatment to either endovascular or open procedure was required in 12.3% and 4.4%, respectively. Resolution of symptoms was observed in 100% for those treated with open procedure and 88.8% for those treated endovascularly. The pooled rate of bowel ischemia in patients treated conservatively was 3.75% (95% confidence interval = 1.15-7.27). Complete remodeling was achieved in 32% and partial in 26% of those who were treated conservatively.

CONCLUSIONS

The majority of symptomatic patients with SISAMD were treated conservatively and showed an uncomplicated course and only a small percentage required conversion to endovascular or open repair. This might highlight the benign course of the disease.

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

OBJECTIVE

The aim was to evaluate the outcomes of endovascular treatment with bare stents alone versus stent assisted coiling in isolated mesenteric artery dissection (IMAD) aneurysms.

METHODS

Patients with an IMAD aneurysm who underwent endovascular stenting between February 2010 and February 2017 at one of three institutions were included in this study. Data regarding technical success, procedure time, symptom resolution, complications, changes in IMAD aneurysm, and stent patency were recorded.

RESULTS

A total of 38 patients (35 men) were included, 27 treated with bare stents alone and 11 treated with stent assisted coiling. Technical success was achieved in 100% of patients treated with bare stents and in 81.8% of those treated with stent assisted coiling (p = 0.078). The mean procedure times were 62.6 ± 5.3 min for treatment with bare stents and 116.4 ± 8.4 min for stent assisted coiling (p < 0.001). A total of 23 patients had persistent symptoms before stenting; all symptoms were resolved within 3.0 ± 0.7 days. No procedure related major complications occurred. Over 30.2 ± 18.1 months of follow up, complete resolution of the IMAD aneurysm was achieved in all patients; good stent patency and in stent re-stenosis were achieved in 65.8% and 34.2% patients, respectively. There were no occlusions of the stented arteries.

CONCLUSIONS

Bare stents alone and stent assisted coiling have high technical success rates and demonstrate good intermediate patency in patients with an IMAD aneurysm. Bare stents alone may serve as an alternative to stent assisted coiling for the management of IMAD aneurysm.

Treatment Strategies and Outcomes of Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection: A Systematic Review and Meta-analysis

Purpose: To analyze the published treatment experience with symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD). Methods: A literature search of the PubMed and Cochrane databases was conducted for articles on symptomatic SISMAD published in English from January 2007 to January 2018. Case series reporting on both treatment modalities and outcomes were included, while those on traumatic or iatrogenic SMA dissection or SMA dissection accompanied by aortic or other visceral artery dissection were excluded. Overall event rates for treated symptomatic SISMAD were calculated using pooled analyses. The rate of initial conservative treatment, the success rate, the rate of conversion to intervention, and the failure rate in patients with vs without antithrombotic therapy were calculated for each study and compared using a meta-analysis of proportions. Results: The 25 articles selected encompassed 616 SISMAD cases, of which 514 were symptomatic cases eligible for the analysis. Among the latter, initial treatment consisted of conservative therapy in 447 (87.0%) patients and surgical interventions in 67 (13.0%) patients [45 (8.7%) endovascular procedures and 22 (4.3%) open surgeries]. Among conservative cases, 238 (53.2%) received antithrombotic therapy while 172 (38.5%) did not; 50 (11.2%) cases were converted to intervention [42 (84%) endovascular]. Conservative treatment was initially used in 85.2% of pooled cases with an 84.7% success rate, a 14.3% rate of conversion to intervention, and conservative treatment failure rates of 17.8% and 10.1% in patients treated with vs without antithrombotic therapy, respectively (p=0.103). Conclusion: Conservative treatment appeared safe and effective in >80% of symptomatic SISMAD cases, without apparent benefit for antithrombotic agent use. Initial or secondary intervention was more often endovascular, with favorable success rates and short-term outcomes. Large, prospective randomized trials with long-term follow-up are warranted on the treatment for symptomatic SISMAD.