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.

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.

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 Strategy and Radiologic Outcomes of Symptomatic Spontaneous Isolated Superior Mesenteric Artery Dissection Based on Angiographic Classification: The Follow-Up Experience in a Single Center.

PURPOSE: To investigate the demographics, clinical features, radiologic measurement, treatment, and outcomes of symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD) according to computed tomography (CT) classification. METHODS: This retrospective study included 201 patients diagnosed with symptomatic SISMAD from November 2014 to December 2020. Symptomatic spontaneous isolated superior mesenteric artery dissection was categorized into four types based on CT images by Yun's angiographic classification. Their clinical characteristics, images features, treatment methods, and radiological outcomes were comparatively analyzed by CT angiographic types. RESULTS: SISMADs were categorized into type I (13.9%) patent false lumen (FL) with both entry and re-entry; type IIa (37.3%), blind pouch of FL; type IIb (43.3%), thrombosed FL; and type III (5.5%), and the occlusion of superior mesenteric artery (SMA). Type IIb, the most common SISMAD, showed the largest true lumen (TL) residual diameter and the lowest percentage of TL stenosis. Type III positioned most proximally to SMA origin and had the maximum dissection length. Symptomatic spontaneous isolated superior mesenteric artery dissections underwent conservative (75.1%), endovascular (22.4%), and surgical (2.5%) treatment. Conservative treatment was more frequent in type I (85.7%) and type IIb (83.9%) than in type IIa (65.3%) and type III (45.5%). Endovascular intervention was more commonly utilized in type IIa (32.0%) and type III (36.4%) than in type I (14.3%) and type IIb (14.9%). Conservative patients achieved FL vanishment/shrinkage (57.8%), stabilization (26.6%), and enlargement (15.6%). After conservative treatment, type I showed angiographic FL stabilization; type IIa achieved FL shrinkage (48.1%), stabilization (22.2%), and enlargement (29.6%); type IIb exhibited FL vanishment/shrinkage (92.0%) and enlargement (8.0%). Cumulative rate of stent patency was 92.3% during 6-year follow-up. CONCLUSIONS: Conservative management with close follow-up is initially provided especially for types I and IIb. Morphological stabilization is more frequent in type I of patent FL with entry and re-entry. False lumen vanishment or shrinkage was more likely to occur in type IIb due to the thrombus absorption. Endovascular intervention has excellent long-term in-stent patency and is predominantly utilized in types IIa and III. Blood flow sustained into a blind-ending FL causes the TL compression and stenosis in type IIa. Type III with the occlusion of SMA has the high risk of bowel ischemia. CLINICAL IMPACT: According to Yun's angiographic classification of spontaneous isolated superior mesenteric artery dissection (SISMAD), type I (13.9%) has patent true and false lumen and the morphological pattern is maintained stable; type IIa (37.3%) possesses a patent blind-ending false lumen which might shrink, remain unchanged, or enlarge; and endovascular intervention is suggested when conservative treatment failed; type IIb (43.3%) recovers spontaneously due to the absorption of false lumen thrombus and conservative treatment is preferentially considered; type III (5.5%) with the occlusion of main trunk carries a high risk of bowel necrosis, early endovascular intervention is proposed, and open surgery might be necessary.

Diagnosis of spontaneous isolated superior mesenteric artery dissection with ultrasound: A case report.

BACKGROUND: Spontaneous isolated superior mesenteric artery dissection (SISMAD) is a rare disease that originates from the superior mesenteric artery, without the presence of aortic and other arterial dissections. Most cases are diagnosed using contrast-enhanced computed tomography (CECT), whereas the application of ultrasound is less common. CASE SUMMARY: Here, we report a case of SISMAD with sudden epigastric pain that worsened as the main symptom after eating. The patient had a long history of hypertension with unknown blood pressure control but no history of smoking or alcohol consumption. This case was initially diagnosed using ultrasound and the results were later confirmed by CECT. After admission, the patient fasted, followed by parenteral nutrition support and fluid supplementation to maintain electrolyte and acid-base balance. Metoprolol succinate sustained-release tablets and aspirin were given as nonoperative treatments. After 1 wk, the symptoms improved, and the patient was discharged. During telephone follow-up, the patient did not develop similar symptoms. CONCLUSION: Whether ultrasound can be used as a routine and noninvasive imaging method for the diagnosis of SISMAD needs further exploration.

Relationship Between Morphological Remodeling and Angiographic Types of Spontaneous Isolated Superior Mesenteric Artery Dissection After Conservative Management: Determinant Affecting Serial Radiologic Courses.

Objective: To monitor the radiological courses of symptomatic spontaneous isolated superior mesenteric artery dissection (SISMAD) after conservation, clarify the relationship between its morphological change and initial imaging classification, and identify these factors that affect dissection remodeling. Methods: Eighty-nine conservative patients with SISMAD who underwent periodic follow-up of computed tomography angiography (CTA) were enrolled. Initial morphologic classification, imaging features and dissection remodeling were analyzed retrospectively. Logistic regression was used to identify predictors for remodeling. Receiver operating characteristics were performed for cutoff threshold. Results: Zerbib classification was adapted and initial CT appearance divided eighty-nine patients into: type I (15.7%), patent false lumen (FL) with both entry and re-entry; type II (37.1%), "cul-de-sac" shaped FL without re-entry; type III (27.0%), thrombosed FL with ulcer-like-projection (ULP); type IV (18%), intramural hematoma; type V (0%), dissecting aneurysm; and type VI (2.2%), total or partial occlusion of superior mesenteric artery (SMA). Follow-up CTA revealed complete remodeling (33.7%), partial remodeling (16.9%), no change (25.8%), type change (13.5%) and dissection progression (10.1%). There was no dissection-related mortality. Type I (92.9%) sustained patent FL and no angiographic change. Type II showed partial remodeling (42.4%), no change (27.3%) and dissection progression (27.3%), and the length of FL enhancement positively predicted dissection progression with the cutoff of 40.3 millimeters. Type III achieved complete remodeling (58.3%) or evolved into type II (41.7%), and the distance between SMA orifice and ULP negatively predicted type change with the cutoff of 23.5 millimeters. Type IV (87.5%) achieved complete remodeling due to hematoma absorption. One patient underwent stent placement for the evolution of ULP into an enlarged blind-ending FL 2 months after conservation. Conclusion: After conservation, patent FL with a distal re-entry is no morphological change, FL thrombosis tends to be resolved, and the "cul-de-sac" shaped FL without re-entry is partially shortened, no change or progressively dilated. FL enhancement length ≥ 40.3 millimeters is a predictor for the blinding-end FL enlargement. Thrombosed FL with ULP evolves into a patent "cul-de-sac" shaped FL when the distance between SMA orifice to ULP is less than 23.5 millimeters. A careful follow-up is necessary for the lesions with demonstrated predictors.

The ratio of superior mesenteric artery diameter to superior mesenteric vein diameter based on non-enhanced computed tomography in the early diagnosis of spontaneous isolated superior mesenteric artery dissection.

BACKGROUND: Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare cause of abdominal pain. The aim of the study is to investigate the role of a new parameter, the ratio of the SMA diameter to the superior mesenteric vein (SMV) diameter (SMA/SMV) based on non-enhanced computed tomography (CT), in the early diagnosis of SISMAD. METHODS: In a registry study from December 2013 to June 2021, 97 abdominal pain SISMAD patients (SISMAD group) admitted to our hospital were enrolled. Meanwhile, the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control group. Student's t-test, Wilcoxon rank-sum test, and Chi-square test were used to compare differences between the SISMAD and control groups. MedCalc was used to generate receiver operating characteristic (ROC) curve. RESULTS: A total of 291 abdominal pain patients, including 97 SISMAD patients and 194 non-SISMAD patients, were included in the current study. The maximum SMA diameter, perivascular exudation, and SMA/SMV based on non-enhanced CT were significant between the two groups (all P<0.05). ROC curves showed that for the maximum SMA diameter, the area under the curve (AUC), cut-off, sensitivity, and specificity were 0.926, 9.80, 93.8%, and 79.4%, respectively. For SMA/SMV, its AUC, cut-off, sensitivity, and specificity were 0.956, 0.83, 88.7%, and 92.3%, respectively. The diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter (P<0.05). The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency (AUC=0.970). CONCLUSION: SMA/SMV may be a potential marker for SISMAD.

Clinical characteristics and misdiagnosis of spontaneous isolated superior mesenteric artery dissection.

BACKGROUND: Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare disease with a potentially fatal pathology. Due to the lack of specificity of clinical characteristics and laboratory tests, misdiagnosis and missed diagnosis are often reported. Therefore, the aim of this study was to investigate the clinical characteristics and misdiagnosis of SISMAD. METHODS: In a registry study from January 2013 to December 2020, 110 patients with SISMAD admitted to the First Affiliated Hospital of Wenzhou Medical University were enrolled. Descriptive methods were used to analyse clinical characteristics, laboratory data, diagnostic method or proof, misdiagnosed cases, plain computed tomography (CT) findings and dissection features. To study the relationship between dissection features and treatment modality, the selected patients were classified into the conservative group (n = 71) and the non-conservative group (n = 39). The Chi-square test and Student's t-test were used to compare the conservative and non-conservative groups. RESULTS: One hundred ten patients with SISMAD, including 100 (90.9%) males and 10 (9.1%) females, with a mean age of 52.4 ± 7.6 years, were enrolled in the study. Relevant associated comorbidities included a history of hypertension in 43 cases (39.1%), smoking in 46 cases (41.8%), and alcohol consumption in 34 cases (30.9%). One hundred four patients (94.5%) presented with abdominal pain. Abnormalities in the C-reactive protein lever, white blood cells count and D-dimer lever were the 3 most common abnormal findings. There were 32 misdiagnosis or missed diagnosis. Fourteen cases were misdiagnosed because of insufficient awareness. Twelve cases were misdiagnosed because of disease features. Twenty cases were misdiagnosed as SMA embolism. Among them, There were 15 cases of Yun type IIb SISMAD. Sixty-six patients underwent plain CT. The maximum SMA diameter was 12.1 (11.3-13.1) mm, and the maximum SMA diameter was located on the left renal vein (LRV) plane in 68.2% of cases. Dissection features observed on contrast-enhanced CT (CECT), CT angiography (CTA), or digital subtraction angiography (DSA) showed that there were 70 cases (63.6%) of Yun type IIb SISMAD, the maximum SMA diameter was 13.0 ± 2.4 mm, the location of the maximum SMA diameter was on the LRV plane in 64.5% of cases, and 7.3% of cases were complicated with intestinal obstruction, including bowel necrosis in 3.6% of cases. There were differences between the conservative group and non-conservative groups in the residual true lumen diameter or degree of true lumen stenosis and the presence of intestinal obstruction or bowel necrosis (all P < 0.05). CONCLUSION: For SISMAD, misdiagnosis and missed diagnosis were usually caused by insufficient awareness and disease features. SISMAD should be considered in the differential diagnosis of patients presenting with unexplained abdominal pain, especially males, patients in the 5th decade of life, patients with hypertension, and patients with an enlarged SMA diameter or a maximum SMA diameter located on the LRV plane on plain CT. Mesenteric CTA or CECT should be recommended for the investigation of these conditions.

The ratio of superior mesenteric artery diameter to superior mesenteric vein diameter based on non-enhanced computed tomography in the early diagnosis of spontaneous isolated superior mesenteric artery dissection / 世界急诊医学杂志（英文）

@#BACKGROUND: Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare cause of abdominal pain. The aim of the study is to investigate the role of a new parameter, the ratio of the SMA diameter to the superior mesenteric vein (SMV) diameter (SMA/SMV) based on non-enhanced computed tomography (CT), in the early diagnosis of SISMAD. METHODS: In a registry study from December 2013 to June 2021, 97 abdominal pain SISMAD patients (SISMAD group) admitted to our hospital were enrolled. Meanwhile, the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control group. Student's t-test, Wilcoxon rank-sum test, and Chi-square test were used to compare differences between the SISMAD and control groups. MedCalc was used to generate receiver operating characteristic (ROC) curve. RESULTS: A total of 291 abdominal pain patients, including 97 SISMAD patients and 194 non-SISMAD patients, were included in the current study. The maximum SMA diameter, perivascular exudation, and SMA/SMV based on non-enhanced CT were significant between the two groups (all P<0.05). ROC curves showed that for the maximum SMA diameter, the area under the curve (AUC), cut-off, sensitivity, and specificity were 0.926, 9.80, 93.8%, and 79.4%, respectively. For SMA/SMV, its AUC, cut-off, sensitivity, and specificity were 0.956, 0.83, 88.7%, and 92.3%, respectively. The diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter (P<0.05). The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency (AUC=0.970). CONCLUSION: SMA/SMV may be a potential marker for SISMAD.

Analysis of influencing factors of therapeutic strategies for spontaneous isolated superior mesenteric artery dissection / 国际外科学杂志

Objective:To investigate the influencing factors and clinical effect analysis of the choice of treatment method for spontaneous isolated superior mesenteric artery dissection (SISMAD).Methods:The clinical data of 35 patients with SISMAD admitted to Beijing Friendship Hospital, Capital Medical University from December 2015 to November 2021 were retrospectively analyzed. They were divided into conservative group ( n=24) and surgical group (endoluminal stent group + open surgery group, n=11). The conservative group was treated with conservative methods, the endoluminal stent group ( n=10) was treated with endoluminal stent placement, and the open surgery group ( n=1) was treated with superior mesenteric artery endarterectomy + angioplasty + ileal resection. The white blood cell (WBC) count on admission, the time of abdominal pain, YOO classification, aorta mesenteric angle(AMA), and the length of hospital stay between the two groups were analyzed. All patients were followed up for more than 24 months, at the end of which the vascular remodeling rate of superior mesenteric artery (SMA) between the two groups was studied. In addition, the primary patency rate and secondary patency rate of intracavitary stents were analyzed. Measurement data that conform to normal distribution were expressed as mean ± standard deviation ( ± s), and independent samples t-test was used for comparison between groups; measurement data that do not conform to normal distribution were expressed as median (interquartile range) [ M( Q1,Q3)], the nonparametric test was used for comparison between groups. Enumeration data were compared between groups using the Chi-square test. Results:Univariate analysis showed that compared with the conservative group, the IVS type in YOO classificationin of surgical group was significantly more than the conservative group. There was no significant difference in WBC, duration of abdominal pain, or AMA at admission ( P>0.05). In addition, the length of hospital stay in the conservative group was significantly shorter than that in the surgical group. No intestinal necrosis occurred in endoluminal stent group. After 24 months of follow-up, the remodeling rate of SMA in the surgical group was higher than that in the conservative group; the primary patency rate of the endoluminal stent group was 87.5%, and the secondary patency rate was 100%. One patient in the conservative group developed SMA dissection aneurysm during 12 months of follow-up and received endovascular treatment. Conclusions:For the treatment of SISMAD, most patients can be cured by conservative treatment. However, for patients with consistent abdominal pain and IVS type in YOO classification, if there is no severe manifestation of peritonitis, it is recommended to perform endovascular stent placement as soon as possible to open the blood supply. Meanwhile, the SMA stenting has an ideal long-term patency rate and vascular remodeling rate.

Antithrombotic therapy has no beneficial effect in conservative treatment of spontaneous isolated superior mesenteric arterial dissection.

PURPOSE: Initial conservative treatment with selective endovascular or surgical intervention has shown successful outcomes in the treatment of spontaneous isolated superior mesenteric artery dissection (SISMAD). However, the benefits of antithrombotic therapy as a part of conservative treatment have not been clarified. This study aimed to investigate the clinical course of SISMAD patients and determine differences in clinical outcomes between the antithrombotic and no-antithrombotic groups. METHODS: We retrospectively reviewed 79 cases of SISMAD that were treated conservatively from January 2004 to December 2019 at Chonnam National University Hospital. Clinical outcomes, including the length of hospital stay, pain resolution time, image remodeling, and maximal remodeling time, were compared between the antithrombotic and no-antithrombotic groups. RESULTS: There were 30 patients in the no-antithrombotic group and 49 patients in the antithrombotic group. There was no significant difference in clinical characteristics between the 2 groups, except for dyslipidemia (P = 0.011). The follow-up period (32.6 months vs. 14.6 months, P = 0.009) and imaging follow-up period (31.6 months vs. 13.9 months, P = 0.011) were longer in the antithrombotic group than in the no-antithrombotic group. The length of hospital stay (5.1 days vs. 7.7 days, P = 0.002) was significantly shorter in the no-antithrombotic group than in the antithrombotic group because patients in the antithrombotic group required longer hospitalization for warfarin titration. CONCLUSION: In patients with SISMAD, conservative treatment without antithrombotic therapy may have clinical benefits such as decreased length of hospital stay compared with conservative treatment with antithrombotic therapy.

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.

Clinical characteristics and treatment of spontaneous isolated superior mesenteric artery dissection / 中华消化外科杂志

Objective To investigate the clinical characteristics and treatment of spontaneous isolated superior mesenteric artery dissection (SISMAD).Methods The retrospective cross-sectional study was conducted.The clinical data of 80 patients with SISMAD who were admitted to the Wuhan Union Hospital Affiliated to Huazhong University of Science and Technology from February 2002 to March 2017 were collected.All the patients underwent computed tomographic angiography (CTA) and digital subtraction angiography (DSA) examinations,and then received conservative medical treatment,endovascular interventional treatment or exploratory laparotomy and revascularization.Observation indicators:(1) clinical features;(2) treatment;(3) follow-up.Follow-up using outpatient examination and telephone interview was performed once at 1,6 and 12 months after discharge and once every year after 1 year up to March 2017.Follow-up included recurrence of abdominal pain,changes of superior mesenteric artery (SMA) dissection or changes of SMA and remodeling of dissection after stent implantation.Measurement data were represented as average (range).Results (1) Clinical features:①) Clinical manifestation:75 of 80 patients had symptoms,and 5 without symptoms were diagnosed during health examination.Of 75 patients with symptoms,abdominal pain was the first symptom,with the main of the peri-umbilicus and epigastric pains,without peritoneal irritation sign,including 14 with nausea and vomiting and 4 with bloody stool.②) Results of imaging examination:80 patients were confirmed by CTA examination.CTA showed that there was local thickening of SMA,true and false double-lumen formation,thinner true arterial lumen with visible intimal flap shadow and thrombosis in the false lumen.Results of CTA showed that the first break was located within 1-6 cm from opening of SMA in 77 patients and in the middle and distal segment of SMA in 3 patients,without aortic dissection (AD).(2) Treatment:of 75 patients with symptoms,53 received conservative medical treatment with an effective rate of 70.7％ (53/75),average time of symptomatic remission was 5 days (range,1-12 days);22 received stent imnplantation via right femoral artery approach using self-expanding bare stent or covered stent,with a success rate of implantation of 95.5％ (21/22),including 21 with successful implantations and 1 with false implantation.One patient with false implantation had symptomatic remission after 1-week conservative medical treatment,and there was no exploratory laparotomy and revascularization.Five patients without symptom were required to control blood pressure and get regular follow-up,without other intervention.(3) Follow-up:75 patients with symptoms were followed up for 36 month (range,1-60 months).During follow-up,of 53 patients with conservative medical treatment,2 patients had significant progressions of SMA dissection by CTA examination,1 had recurrence and exacerbation of abdominal pain accompanied with bloody stool at 2-month follow-up,showing an aneurism of SMA dissection by DSA examination,and 1 had recurrence of abdominal pain at 1-year follow-up,both patients were improved after stent implantation;other 51 had no recurrence.Of 22 patients with stent implantation,1 had repeated abdominal pain during follow-up and the symptom became aggravated at 1-year follow-up,showing a thrombosis fonnation and proximal stenosis by CTA examination,and then underwent stent implantation in the proximal stenosis after anticoagulant therapy;SMA dissection of 1 patient completely healed at 2-year follow-up by CTA examination;other 20 patients had stent patency.Five patients without symptom had regular follow-up,showing no disease progression.Conclusions The symptoms of SISMAD are different,and abdominal pain is the one of main symptoms.At present,treatment regimens include conservative medical treatment,endovascular interventional treatment and surgery,and individualized treatment is decided according to clinical symptoms and physical signs of patients and imaging examinations.

The value of a new image classification system for planning treatment and prognosis of spontaneous isolated superior mesenteric artery dissection.

OBJECTIVE: To aid diagnosis of spontaneous isolated superior mesenteric artery dissection and planning management, we investigated the role of classification of features as observed on computed tomography angiography images. METHODS: A retrospective study was conducted, comprising computed tomography angiography images and clinical data of 28 consecutive patients with spontaneous isolated superior mesenteric artery dissection. Based on the computed tomography angiography images, a new classification for spontaneous isolated superior mesenteric artery dissection was proposed. Patients with intestinal ischemia not relieved or worsened after 10 days of conservative treatment underwent surgery or stenting. All patients were followed up with computed tomography angiography. RESULTS: Spontaneous isolated superior mesenteric artery dissection was categorized into five types (I-V). Type III was further divided into subtypes IIIa-IIIc. Spontaneous isolated superior mesenteric artery dissection IIIa and IV typified nine (32.1%) and seven (25%) patients, respectively. Six (21.4%) patients had aortic or branch artery abnormalities and 21 (78%) showed prior intestinal ischemia. Four (14.3%) patients had intestinal ischemia and underwent surgery or stenting. CONCLUSIONS: Spontaneous isolated superior mesenteric artery dissection type IIIa is more likely to occur than other types. Long-term computed tomography angiography follow-up is valuable for determining treatment strategy for spontaneous isolated superior mesenteric artery dissection. Conservative therapy with anticoagulants is recommended for five days, and surgery or stenting should be considered if symptoms of intestinal ischemia are not relieved. Stent implantation provides relatively satisfactory mid-term outcome for true lumen construction of the superior mesenteric artery.

Diagnosis and treatment of spontaneous isolated superior mesenteric artery dissection / 中华消化外科杂志

With the development of imaging technology,the reports of spontaneous isolated superior mesenteric artery dissection become more frequently,but there is no consensus on the therapeutic plans which consist of conservative therapy,endovascular treatment and surgical treatment.Therefore,the related questions of the spontaneous isolated superior mesenteric artery dissection will be discussed in order to improve the diagnosis and treatment of vascular diseases of digestive tract with a review of literatures.