Management of isolated superior mesenteric artery dissection

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.

Outcomes and radiographic findings of symptomatic isolated mesenteric artery dissection with conservative management

OBJECTIVES

The aim of this study was to evaluate the computed tomography follow-up outcomes and radiographic findings of symptomatic isolated mesenteric artery dissection (IMAD) after conservative management.

METHODS

In this retrospective study, 130 consecutive patients with symptomatic IMAD from three institutions were enrolled from January 2011 to December 2019. The general epidemiological data, clinical manifestations, first-episode symptoms, imaging findings, and treatment strategy selection were analyzed from the medical records.

RESULTS

Among 130 patients diagnosed with symptomatic IMAD, positive remodeling of the SMA was achieved in 75.38% (98/130), and negative remodeling of the SMA was achieved in 24.62% (32/130). In the positive remodeling group, complete remodeling was achieved 39.23% (51/130) (type I 6 patients, type IIa 10 patients, type IIb 35 patients), in which type IIb was the most (p = 0.004). Moreover, of the 32 patients in whom negative remodeling of the SMA was achieved, significant differences were observed between the type IIa with respect to dissecting aneurysm formation (p = 0.04).Of the seven factors analyzed with a logistic regression model identified three factors significantly associated with negative remodeling: length of dissection (Waldχ² 13.331; OR 6.945; 95% CI 2.762-10.498; p = 0.014), true lumen residual diameter (TLRD) (Waldχ² 9.626; OR 7.85; 95% CI 1.892-19.063; p = 0.022), and branch involvement (Waldχ2 11.812; OR 7.247; 95% CI 1.245-14.830; p = 0.011).

CONCLUSION

The prognosis of most symptomatic IMAD has a tendency to positive remodeling after conservative management, in which the initial type IIb classification is common. In contrast, risk factors for negative remodeling were type IIa, length of dissection, TLRD, and branch involvement. Patients with these morphological characteristics may not benefit from conservative management.

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.

Classification of spontaneous isolated superior mesenteric artery dissection: correlation with multi-detector CT features and clinical presentation

PURPOSE

The purpose of the study is to propose a computed tomography (CT) classification of spontaneous isolated superior mesenteric artery dissection (SISMAD) correlated with clinical presentation METHODS: We retrospectively reviewed CT images of 40 patients with SISMAD at our institution from 2006 to 2015 and proposed a new classification: type I, patent false lumen with both entry and re-entry; type II, patent false lumen without re-entry; type III, completely or partially thrombosed false lumen; and type IV, thrombosed false lumen with ulcer-like projection. Additionally, we included a subtype (S) at each type when there was either a long segment of dissection and/or significant true lumen stenosis. CT features were statistically analyzed using Fisher's exact and Mann-Whitney test.

RESULTS

The CT findings classified patients as type I (15%), type II (12.5%), type III (35%), and type IV (37.5%). Of the 40 patients, 25 (62.5%) were symptomatic. There was a significantly different proportion of each type between symptomatic and asymptomatic patients (p = 0.005). There were 25 patients with subtype (S); no type I or II, 12 type III, and 13 type IV. The symptomatic patients showed longer dissection tendency and more severe true lumen stenosis (78% vs. 53%, p = 0.000) compared with asymptomatic patients.

CONCLUSION

The proposed multi-detector CT classification of SISMAD correlates with clinical presentation. This new classification could be helpful for treatment planning.

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

OBJECTIVE

Spontaneous isolated celiac artery dissection (SICAD) and spontaneous isolated superior mesenteric artery dissection (SISMAD) represent the major types of spontaneous visceral artery dissection. However, no quantitative meta-analysis of SICAD and SISMAD is available. The aim of our study was to pool current evidence concerning basic profiles, treatment strategies, long-term adverse events, and morphologic changes of lesioned vessels in SICAD and SISMAD patients.

METHODS

We searched the MEDLINE, Embase, Scopus, and Cochrane Databases (January 1, 1946-September 21, 2017) for studies of SICAD and SISMAD. Related cohort studies or case series with sample size larger than 10 were included. Two reviewers independently extracted and summarized the data. A random-effects model was used to calculate pooled estimates.

RESULTS

In total, 43 studies were included. An estimated 8% (95% confidence interval [CI], 0.01-0.21) symptomatic SICAD and 12% (95% CI, 0.06-0.19) symptomatic SISMAD patients with initial conservative management required secondary intervention during follow-up, whereas none of the asymptomatic patients treated conservatively required secondary intervention. As for morphologic changes during follow-up, a higher proportion of SICAD patients (64%; 95% CI, 0.47-0.80) achieved complete remodeling compared with SISMAD patients (25%; 95% CI, 0.19-0.32), and an estimated 6% (95% CI, 0.00-0.16) of SICAD and 12% (95% CI, 0.05-0.20) of SISMAD patients had morphologic progression. Overall, the pooled estimate of long-term all-cause mortality was 0% (95% CI, 0.00-0.03) in SICAD and 1% (95% CI, 0.00-0.02) in SISMAD. When stratified by symptoms, symptomatic patients were associated with a significantly increased probability of accomplishing complete remodeling (odds ratio, 3.95; 95% CI, 1.31-11.85) compared with asymptomatic patients.

CONCLUSIONS

Initial conservative treatment is safe for asymptomatic SICAD or SISMAD patients. Symptomatic patients managed conservatively have relatively high occurrence of late secondary intervention, which may require closer surveillance, especially in SISMAD because of a lower rate of remodeling.

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.