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

Abstract

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.

Keywords

Isolated superior mesenteric artery dissection bare stent treatment bare stent-assisted coiling treatment prognosis remodeling

Introduction

Spontaneous isolated superior mesenteric artery dissection (ISMAD) without aortic dissection remains uncommon.¹ As computed tomography (CT) has become increasingly popular and developed, it has led to an increase in the number of case studies and retrospective studies. Thus, it suggests that there may have been underestimations of the incidence of this disease in the past. Though ISMAD can be revealed in an incidental CT scan, and it does not require treatment,^2,3 the disease can also present as acute abdominal pain and can progress to rupture of dissection, occlusion of the superior mesenteric artery (SMA), or ischemia/necrosis of the bowel.¹

Symptom relief, restoration of true lumen circulation, and prevention of false lumen extension and rupture are the main objectives of treatment.⁴ There are different treatment approaches available, such as conservative, endovascular, and open surgery. In spite of this, no consensus has been reached regarding first-line management. When bowel resection is necessary, open surgical repair is usually performed.¹ In recently published reviews, conservative management has been frequently reported as the initial treatment, with symptom relief rates ranging from 66.8% to 86.6%.^2,3 However, it may take several days to evaluate the effect, those who fail conservative treatments may suffer severe consequences, and additional intervention will be required.⁵ Concerning follow-up outcomes, the complete remodeling rate of ISMAD varies between 15.2% and 64%, raising concerns about long-term effects.

Endovascular treatments (EVT) achieve satisfying rates of overall symptom relief (95%–100%) and the remodeling rate varies from 88.3% to 95.5% with a favorable stent patency rate in midterm follow-up.^3,5,6 However, bare stent treatment (BST) and bare stent-assisted coiling treatment (BSACT) have not been directly compared in these studies. It is not yet understood whether these two approaches have an impact on the results due to the limited number of related studies.

In this study, we compared the early and mid-term outcomes of BST and BSACT to determine the more effective remedy for systematic ISMAD with a patent false lumen.

Materials and methods

Study population

The study was conducted in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of the Second Affiliated Hospital, Chongqing Medical University (No. 2023100) on January 2023, with a waiver of informed consent. Consecutive patients diagnosed with ISMAD from the Second Affiliated Hospital, Chongqing Medical University, were included from previous medical records between January 2016 and December 2021 in the study. Exclusion criteria were listed as follows: (a) ISMAD without patent false lumen; (b) patients with conservative treatment or open surgery; (c) patients without related symptoms; (d) patients with concomitant coeliac dissection, inferior mesenteric artery, aortic dissection, vasculitis, or other autoimmune diseases; and (e) patients with diffuse peritonitis or initially underwent open surgery. Each patient's medical records were examined for clinical information, primarily including general epidemiological data, symptoms, findings of the image, and treatment options.

Diagnosis and classification of image

Spiral computed tomography angiography (CTA) revealed a diagnosis of ISMAD based on intimal flaps in the superior mesenteric artery (SMA) with false lumen thrombosis or not. Based on the Yun classification,⁷ symptomatic ISMAD were classified into the following categories: type I (entry and re-entry tears visible, and patent false lumen), type IIa (only entry tears visible and patent false lumen), type IIb (thrombosis of the false lumen and patent true lumen), and type III (occlusion of both true and false lumens). Distance between the SMA ostium and the dissection origin, length of the dissection, and true lumen stenosis (true lumen size when compared with adjacent normal SMA size) were measured on CT.

Definition

In the follow-up CTA, complete remodeling was defined as the absence of residual arterial dissection with total thrombosis of the false lumen and without stenosis of the SMA. Incomplete remodeling has been defined as an improved true lumen of the SMA with a narrowed, but not fully thrombosed false lumen.⁸ A focal SMA diameter increase > 50% was defined as an aneurysm.⁹

Treatment strategies

The patient received initial conservative treatment and preoperative preparations, including controlling blood pressure, parenteral nutrition, bowel rest, fasting, and anticoagulation. Subsequently, EVT was performed on the next operation day. An approach involving the femoral or brachial artery was employed. Through the puncture site, a 6F vascular sheath was inserted and 80 IU/kg heparin was injected. After that, a 5F MPA multifunction catheter (Cordis, Miami Lakes, USA) was utilized to perform selective SMA angiography, to determine morphological classification and the distal stent landing zone. Recanalization of the true SMA lumen was performed using a 0.018-inch guide wire (V18, Boston Scientific, Marlborough, USA), and bare self-expanding stents (Biotronik AG, Buelach, Switzerland) were deployed with their proximal ends extending into the aorta. A second stent was introduced in an overlapping manner if the dissection length exceeded the primary stent. In type IIb and III dissections, the pseudolumens are already thrombosed and do not require coiling, whereas in type I and IIa dissections, the application of BST or BSACT depends mainly on the surgeon's preference. Among those patients who underwent stent-assisted coiling, the patent false lumen was catheterized with stent mesh using microcatheters (Progreat, Terumo, Tokyo, Japan) and then coiled with 2 to 4 pushable microcoils (Cook, Bloomington, IN, USA). Lastly, angiography was repeated to assess the improvement in distal blood supply.

Post-procedural care

For anticoagulation, low molecular weight heparin (100 IU/kg) was used twice daily after the stent deployment. Patients were closely monitored for procedure-related complications and potential symptoms or signs of worsening. Once the symptoms had completely resolved, the diet returned to normal. Following discharge, all patients were given antiplatelet therapy, including 75 mg of clopidogrel per day for at least three months and 100 mg of aspirin per day for at least a year. The operation data and early outcomes were collected.

Clinical follow-up

A one-, three-, and six-month outpatient clinic visit was scheduled during the first year, and an annual outpatient clinic visit thereafter. The CTA was repeated at the time of follow-up. When necessary, more frequent evaluations were conducted. At these time points, relevant information was also collected for the evaluation of remodeling rate, stent patency, and adverse events (recurrence of abdominal pain and aneurysm formation).

Statistical analysis

GraphPad Prism (Version 9, GraphPad Software, San Diego, CA, USA) and R software (Version 3.5.3) were used for data visualization and statistical analyses. Continuous data were presented as mean ± standard deviation or median (range) and categorical data were presented as a percentage. Statistical analysis was performed with the Student t-test, chi-square test, or Fisher's exact test. If data for either normality or variance tests failed, the non-parametric Mann–Whitney U-test was used. The cumulative complete remodeling rate and cumulative adverse event-free survival rate were generated with GraphPad Prism (Kaplan-Meier curve). A p-value of <0.05 was defined as statistically significant.

Results

Patients

From January 2016 to December 2021, 146 consecutive patients were diagnosed with ISMAD. Patients were excluded because of ISMAD without patent false lumen (Yun classification: type IIb and type III; 20 cases), conservative treatment (16 cases), no symptoms (18 cases), concomitant aortic dissection (two cases), or emergent open surgery (five cases). Therefore, a total of 85 patients (83 males) were enrolled in this retrospective study. The median age of these patients was 53 years old (range 36–70 years) and almost half of the patients smoked. There were eight patients (9.4%) with nausea/vomiting, two patients (2.4%) with hematochezia, and all of the symptomatic patients who experienced abdominal pain. Neither an infarction nor necrosis of the intestinal wall was found. The mean dissection length was 61.5 ± 16.3 mm and every patient had true lumen stenosis (> 50%). Based on CTA findings, our patients fall into type I, 45.9% (n = 39), and type IIa, 54.1% (n = 46) based on the Yun classification. A summary of demographic data can be found in Table 1.

Table 1.

Baseline characteristics of study patients.

Characteristic	Total (N = 85)	BMT (n = 29)	BMACT (n = 56)	p value
Age (range), year	52.5 ± 7.8	51.8 ± 5.1	52.8 ± 8.8	0.573
Male	83 (97.6)	28 (96.6)	55 (98.2)	0.230
Smoking	40 (47.1)	13 (44.8)	27 (48.2)	0.767
Hypertension	10 (11.8)	3 (10.3)	7 (12.5)	0.770
Renal dysfunction	1 (1.1)	0 (0)	1 (1.9)	1
Use of statins	11 (12.9)	4 (13.8)	7 (12.5)	0.866
Use antiplatelet drugs	12 (14.1)	4 (13.8)	8 (14.3)	0.951
Symptoms
Abdominal pain	85 (100)	29 (100)	56 (100)	1
Hematochezia	2 (2.4)	1 (3.4)	1 (1.8)	1
Nausea/vomiting	8 (9.4)	2 (6.9)	6 (10.7)	0.71
Characteristics of dissection
Mean length (mm)	61.5 ± 16.3	59.4 ± 19.6	62.7 ± 14.3	0.173
Mean distance (mm)^a	24.4 ± 7.8	24.4 ± 7.8	20.5 ± 4.9	0.018
True lumen stenosis (> 50%)	85 (100)	29 (100)	56 (100)	1
The Yun classification				0.216
Type I	39 (45.9)	16 (55.1)	23 (41.1)
Type IIa	46 (54.1)	13 (44.9)	33 (58.9)
Type IIb		0	0
Type III		0	0

BMT: bare stent treatment; BMACT: bare stent-assisted coiling treatment.

Continuous data were presented as mean ± standard deviation and categorical data were presented as n (%) unless specified.

Distance between the ostium of the mesenteric artery and the entry point of the dissection aneurysm.

Treatments

Among 85 patients 34.1% (n = 29) adopted BST and 65.9% (n = 56) underwent BSACT. Two stents were implanted in 12 patients (41.4%) with BST and 26 patients (46.4%) with BSACT (p = 0.657). The procedure duration was shorter in BST compared to BSACT (65.4 ± 7.6 min vs. 91.8 ± 8.3 min, p < 0.001). The related data are shown in Table 2.

Table 2.

Treatments and outcomes of study patients.

Characteristic	BMT (n = 29)	BMACT (n = 56)	p value
Treatment
Single stent	17 (58.6)	30 (53.6)	0.657
Overlapping stent	12 (41.4)	26 (46.4)	0.657
Diameter of stent (mm)	7.41 ± 0.92 (6–8)	7.37 ± 0.94 (6–8)	0.785
Procedure time (minutes)	65.4 ± 7.6	91.8 ± 8.3	< 0.001
Outcomes
Symptom relief	29 (100)	56 (100)	1
Fasting days	4.3 ± 1.3	3.5 ± 1.8	0.007
Complications	1 (3.4)	2 (3.6)	1
Time to improved symptoms (days)^a	2.5 ± 0.7	1.8 ± 0.8	< 0.001
Median length of hospital stay, days	6.3 ± 1.3	6.4 ± 1.5	0.354

BMT: bare stent treatment; BMACT: bare stent-assisted coiling treatment.

Continuous data were presented as mean ± standard deviation and categorical data were presented as n (%) unless specified.

Time to improve symptoms represents the time delay between the intervention and the relief of symptoms.

Outcomes

There was no technical failure in either BST or BSAT. The symptoms were relieved in all patients (100%) with BST and BSACT. Fasting days were shorter in BSACT (3.5 ± 1.8 days vs. 4.3 ± 1.3 days) and the postoperative symptom relief time was longer in BST than in BSACT (2.5 ± 0.7days vs. 1.8 ± 0.9 days, p < 0.001). There was no significant difference in the length of hospital stay between the two procedures (p = 0.354). No major complications occurred, but three patients developed minor complications. One was a subcutaneous hematoma in BST and recovered without additional treatment. The other two were pseudoaneurysms at the puncture site in BSACT, which required local injection of thrombin. These early outcomes were revealed in Table 2.

Clinical follow-up

During the follow-up (31 months, range 3–63 months), the cumulative complete remodeling rate was higher in BSACT (100% vs. 75.3%, p < 0.001) without unchanged dissection (Figure 1). Additionally, the prevalence of adverse events for abdominal pain recurrence and formation of the aneurysm shows no significant difference between BSACT and BST. No symptoms were identified in the two patients with aneurysm formation in BST, and these patients were observed closely. In terms of primary patency, the results were favorable. Only one stent occluded at one month, as a result, the primary patency was 96.3% in BST and 100% in BSACT. Data summaries for follow-up are presented in Table 3.

Figure 1.

Cumulative complete remodeling rate in patients with symptomatic isolated superior mesenteric artery dissection. The cumulative complete remodeling rate was 59.3%, 63.0%, and 75.3% at one, three, and five years in patients with bare stent treatment compared with 100% in patients with bare stent-assisted coiling treatment (p < 0.001).

Table 3.

Follow-up of patients treated for symptomatic isolated superior mesenteric artery dissection.

Characteristic	BMT (n = 27)	BMACT (n = 54)	p value
Follow-up time (months)	31 (3–60)	31 (3–60)	0.616
Follow-up time (months)	32 ± 14	29 ± 16	0.616
Remodeling of dissections
Complete remodeling	19 (70.4)	54 (100)	< 0.001
Incomplete remodeling	7 (25.9)	0
Unchanged dissection	4 (3.7)	0
Patent false lumen	11 (40.7)	0 (0)	< 0.001
Adverse event
Recurrent abdominal pain	0 (0)	0 (0)	1
Aneurysm formation	2 (7.4)	0 (0)	0.108
Primary patency of stents	40 (96.3)	54 (100)	0.333

BMT: bare stent treatment; BMACT: bare stent-assisted coiling treatment.

Continuous data were presented as mean ± standard deviation and categorical data were presented as n (%) unless specified.

Discussion

ISMAD can be revealed occasionally on CT scans and does not always indicate intestinal ischemia. Careful observation could manage this without additional treatment.^10–12 In contrast, systematic ISMAD requires treatment that controls symptoms effectively and prevents complications (such as intestinal necrosis) with a high degree of complete remodeling.^1,13 Despite this, the first-line treatment for symptomatic ISMAD remains controversial. Although many studies work on the same topic, most of the studies only compare conservative therapy and endovascular treatment (bare stents) and do not take into account whether BSACT could affect the early and follow-up outcomes.^14–17 In this study, we compare the early and midterm outcomes between BST and BSACT. In the early outcome, we found that there was no significant difference in symptom relief rates or hospital stays. In the follow-up outcome, it was found that BSACT had a higher complete remodeling rate than BST.

If a patient has symptomatic ISMAD, the blood streams perfuse the false lumen, resulting in progressive narrowing of the true lumen. In our study, all the symptomatic patients presented abdominal pain with the true lumen of SMA stenosis (> 50%). Treatment consists of preventing the dissection from further expanding, ensuring adequate blood flow to the distal tissues, preventing rupture of the artery, and relieving abdominal symptoms.¹⁴ The conservative treatment for SMA reduces the demand for blood, allowing the patient to establish collateral circulation within a reasonable period. Through the use of stents, EVT can reopen the compressed SMA and therefore directly resolve intestinal ischemia.^18,19 The use of EVT for ISMAD for the first time was published in a case report in 2000,¹⁶ and since then there have been several case series that have demonstrated promising results.^5,17,20,21 In this study, the symptoms were relieved 100% in both BST and BSACT groups, and hospital stays showed no significant difference (6.3 ± 1.3 days vs. 6.4 ± 1.5 days, p = 0.354). According to the ESVS guideline, it is reported that the medical treatment of symptomatic ISMAD could fail in 16% of patients, and further operations were needed which means a lower symptom relief rate and longer hospital stays.¹ Thus, in the present authors’ practice, the use of EVT has high efficiency in restoring blood supply and controlling symptoms. Stent-assisted coiling seems not superior to stent alone in symptom relief and hospital stay.

EVT could achieve a high success rate with a low complication rate.^20,22 In our study, 100% technique success is achieved in both BST and BSACT. This result accords with the former reports. The technical failure occurred in several cases in which a narrow distal SMA (impossible to implant the tiniest stent), or failure to access the true lumen of the SMA, was encountered.²³ In this study, three complications occurred (2.4% in BST and 3.6% in BSACT) and all of them were minor complications including subcutaneous hematoma and pseudoaneurysms at the puncture site. Besides death, no other complications occurred, including bowel necrosis or peritonitis, nor did the false lumen block off branches.

One study reported that at two years following conservative treatment, 64% of patients with symptomatic ISMAD had achieved complete remodeling.²⁴ A lower rate of complete remodeling was reported by other articles, ranging from 15.2% to 41.7%.^9,25,26 Literature showed a much higher complete remodeling rate (88.3%) with EVT at a five-year follow-up, but it did not take into account whether coiling in the false lumen made a difference in the final result.⁵ This study reported cumulative complete remodeling rate of the five years was 75.3% (BST) and 100% (BSACT), p < 0.001. After the procedure, the majority of complete remodeling took place within three months. It seems that stents-assisted coiling could early and rapid reduction of blood flow to the dissection lumen which will result in better remodeling results. In the meantime, we need further studies to confirm this outcome.

A case series demonstrated 100% (5/5) patency during eight months of follow-up after implantation of the SMA stents (range 4–38 months).²⁷ In another study, the primary stent patency was 99.1%, and one occlusion occurred three months after EVT (range 6–60 months and median 29.7 months).⁵ According to the present study, the primary patency in BST was 97.6% and in BSACT was 100%. Only one stent occlusion occurred one month after bare stent implantation. The remaining patients’ stents were kept patent during the follow-up period.

There were several limitations to this study. First, the study is retrospective rather than randomized controlled. Moreover, the sample size was not sufficiently large. In the last, only three patients were followed up for five years, since most patients were enrolled within the last five years. The results of this study should be interpreted with caution since they may represent inaccurate estimates of the five-year cumulative primary patency and adverse event-free survival rate.

Conclusion

BST and BSACT for symptomatic ISMAD with a patent false lumen have the same satisfying early outcome in symptom relief rate and hospital stays. In the midterm follow-up, BSACT had the higher cumulative complete remodeling rate, though the adverse events and primary stent patency showed no difference. BSACT is effective for symptomatic ISMAD with a patent false lumen and can be prioritized to treat this condition.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Chongqing Science and Technology Project (Chongqing Municipal Science and Technology Bureau) (grant number cstc2021jcyj-msxmX0219).

ORCID iDs

Yikuan Chen

Hailong Luo

Author biographies

Huan Wu, MD, Chief Physician of The Second Affiliated Hospital of Chongqing Medical University.

Bo Tang, MD, Professor of of The Second Affiliated Hospital of Chongqing Medical University.

Haolong Zhang, MD, Chief Physician of The Second Affiliated Hospital of Chongqing Medical University.

Kun Ran, MD, Chief Physician of The Second Affiliated Hospital of Chongqing Medical University.

Yikuan Chen, MD, Professor of The Second Affiliated Hospital of Chongqing Medical University.

Hailong Luo, MD, Chief Physician of The Second Affiliated Hospital of Chongqing Medical University.

References

Björck

Koelemay

Acosta

, et al. Editor’s choice – management of the diseases of mesenteric arteries and veins: clinical practice guidelines of the European Society of Vascular Surgery (ESVS). Eur J Vasc Endovasc Surg 2017; 53: 460–510.

Kimura

Kato

Inoko

. Outcomes of treatment strategies for isolated spontaneous dissection of the superior mesenteric artery: a systematic review. Ann Vasc Surg 2018; 47: 284–290.

Luan

Guan

, et al. Isolated superior mesenteric artery dissection in China. J Vasc Surg 2016; 63: 530–536.

Mkangala

Liang

Dong

, et al. 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. Wideochirurgia I Inne Techniki Maloinwazyjne 2020; 15: 608–619.

Qiu

, et al. Mid-term results of endovascular treatment for spontaneous isolated dissection of the superior mesenteric artery. Eur J Vasc Endovasc Surg 2019; 58: 88–95.

Sun

Wang

Que

, et al. Management of patients with uncomplicated symptomatic isolated mesenteric artery dissection: a multicentre experience. Eur J Vasc Endovasc Surg 2022; 64: 507–514.

Yun

Kim

Park

, et al. Clinical and angiographic follow-up of spontaneous isolated superior mesenteric artery dissection. Eur J Vasc Endovasc Surg 2009; 37: 572–577.

Shi

Zhao

, et al. Management of symptomatic spontaneous isolated superior mesenteric artery dissection: a single centre experience with mid-term follow up. Eur J Vasc Endovasc Surg 2020; 60: 863–871.

Jeong

M-J

Kwon

Kim

, et al. Clinical outcomes of conservative treatment in patients with symptomatic isolated spontaneous renal artery dissection and comparison with superior mesenteric artery dissection. Eur J Vasc Endovasc Surg 2018; 56: 291–297.

10.

Kimura

Kato

Nagao

, et al. Outcomes and radiographic findings of isolated spontaneous superior mesenteric artery dissection. Eur J Vasc Endovasc Surg 2017; 53: 276–281.

11.

Loeffler

Obara

Fujimura

, et al. Medical therapy and intervention do not improve uncomplicated isolated mesenteric artery dissection outcomes over observation alone. J Vasc Surg 2017; 66: 202–208.

12.

Nuzzo

Castier

Corcos

. Superior mesenteric artery dissection does not necessarily mean acute mesenteric ischemia. American Journal of Emergency Medicine 2016; 34: 2457.

13.

Aboyans

Ricco

Bartelink

MLEL

, et al. 2017 ESC guidelines on the diagnosis and treatment of peripheral arterial diseases, in collaboration with the European Society for Vascular Surgery (ESVS). Eur Heart J 2018; 39: 763–816.

14.

Gao

, et al. Management strategy based on disease stages for patients with symptomatic isolated mesenteric artery dissection. Ann Vasc Surg 2020; 64: 276–284.

15.

Garrett

. Options for treatment of spontaneous mesenteric artery dissection. J Vasc Surg 2014; 59: 1432–1433.

16.

Leung

Schneider

Kubik-Huch

, et al. Acute mesenteric ischemia caused by spontaneous isolated dissection of the superior mesenteric artery: treatment by percutaneous stent placement. Eur Radiol 2000; 10: 1916–1919.

17.

Kim

Yoon

Seong

, et al. Spontaneous dissection of superior mesenteric artery: long-term outcome of stent placement. J Vasc Interv Radiol 2017; 28: 1722–1726.

18.

Wen

Wang

, et al. Endovascular stent-graft repair of spontaneous isolated dissection of the superior mesenteric artery. Cardiovasc Intervent Radiol 2018; 41: 692–698.

19.

Chu

Hsu

Chen

, et al. Endovascular repair of spontaneous isolated dissection of the superior mesenteric artery. Clin Radiol 2012; 67: 32–37.

20.

, et al. A modified endovascular technique for treating spontaneous isolated superior mesenteric artery dissection and the early to medium-term outcomes. Heliyon 2019; 5: e01354.

21.

Shao

Zhang

, et al. Long-term outcomes of conservative treatment and endovascular treatment in patients with symptomatic spontaneous isolated superior mesenteric artery dissection: a single-center experience. BMC Cardiovasc Disord 2020; 20: 256.

22.

Luan

, et al. Vasodilator and endovascular therapy for isolated superior mesenteric artery dissection. J Vasc Surg 2013; 57: 1612–1620.

23.

Dong

Ning

, et al. Failures and lessons in the endovascular treatment of symptomatic isolated dissection of the superior mesenteric artery. Ann Vasc Surg 2016; 31: 152–162.

24.

Tomita

Obara

Sekimoto

, et al. Evolution of computed tomographic characteristics of spontaneous isolated superior mesenteric artery dissection during conservative management. Circ J 2016; 80: 1452–1459.

25.

Park

Kim

, et al. Natural history of spontaneous isolated superior mesenteric artery dissection derived from follow-up after conservative treatment. J Vasc Surg 2011; 54: 1727–1733.

26.

Heo

S-H

Kim

Y-W

Woo

S-Y

, et al. Treatment strategy based on the natural course for patients with spontaneous isolated superior mesenteric artery dissection. J Vasc Surg 2017; 65: 1142–1151.

27.

Jia

Zhao

Tian

, et al. Initial and middle-term results of treatment for symptomatic spontaneous isolated dissection of superior mesenteric artery. Eur J Vasc Endovasc Surg 2013; 45: 502–508.