Superior Mesenteric Artery Dissection Research Articles

Isolated superior mesenteric artery dissection with concomitant vascular aberrancy: Extremely rare cases and clinical implications.

Vascular aberrancy of superior mesenteric artery (SMA) may contribute to the occurrence of SMA dissection. However, there is no direct evidence to support this hypothesis. Etiology, natural history, classification, and treatment options of ISMAD are still in controversial at some degree. We also review the current understanding of ISMAD based on our results. Out of 57 patients, 2 cases of isolated superior mesenteric artery dissection (ISMAD) which concomitant with replaced common hepatic artery with SMA origin, are first reported. Two patients have no any typical etiological factors, such as atherosclerosis, hypertension, long-term smoking, and connective tissue disease. The contrast-enhanced computed tomography and (or) angiography showed concomitant SMA aberrancy. They have 81.2°, 132.7° SMA angle, respectively. After conservative treatment of 4, 6days, respectively, these 2 patients were discharged smoothly. Vascular aberrancy may be a new identified risk factor for ISMAD. Even in ISMAD cases with vascular aberrancy, conservative treatment still can be used as first line therapy.

In-stent Restenosis After Stenting for Superior Mesenteric Artery Dissection Is Associated With Stent Landing Zone: From Clinical Prediction to Hemodynamic Mechanisms.

To identify risk factors for in-stent restenosis (ISR) in patients undergoing stent placement for superior mesenteric artery dissection (SMAD) and to determine the hemodynamic mechanism underlying ISR. For this retrospective study, patients with SMAD who had ISR after stent placement were included in the ISR group, and age- and sex-matched patients with SMAD who did not experience ISR after stent placement were included in the control group. Clinical, imaging, and hemodynamic data were assessed. Multivariable regression was used to identify independent ISR risk factors. Structural and fluid dynamics simulations were applied to determine the hemodynamic mechanism underlying the occurrence of ISR. The study population included 26 patients with ISR and 26 control patients. Multivariate analysis demonstrated that stent-to-vascular (S/V) ratio (odds ratio [OR], 1.14; 95% confidence interval [CI]: 1.00-1.29; p=0.045), stent proximal position >10 mm away from the SMA root (OR, 108.67; 95% CI: 3.09-3816.42; p=0.010), and high oscillatory shear index (OSI) area (OR, 1.25; 95% CI: 1.02-1.52; p=0.029) were predictors of ISR. In structural and fluid dynamics simulations, a stent proximal position near the abdominal aorta (AA) or entering into the AA reduced the contact area between the proximal struts of the stent and the vascular wall, and alleviated the distal lumen overdilation. The S/V ratio, stent proximal position away from the SMA root (>10 mm), and high OSI area are independent risk factors for ISR in patients with SMAD undergoing stent placement. Deploying the proximal end of the stent near the AA or entering into the AA appears to improve the hemodynamic environment in the SMA lumen and ultimately reduce the risk of ISR. In-stent restenosis is an uncommon but potentially catastrophic complication after stent placement for the management of superior mesenteric artery dissection. This study identified risk factors for in-stent restenosis and demonstrated that, as long as the stent can fully cover the dissection range, deploying the proximal end of the stent near the abdominal aorta or less entering into the abdominal aorta may reduce the risk of in-stent restenosis in this patient population.

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.

Robotic Pancreaticoduodenectomy with 'SMA-First Approach (Posterior and Right Medial)' and 'Triangle Operation'.

Notable improvements in pancreatic cancer surgery have been due to utilization of the superior mesenteric artery (SMA)-first approach1 and triangle operation (clearance of triangle tissue between origin of SMA and celiac artery).2 The SMA-first approach was originally defined to assess resectability before taking the irreversible surgical steps. However, in the present era, resectability is judged by the preoperative radiology, and the benefit of the SMA-first approach is by improving the R0 resection rate and reducing blood loss. The basic principle is to identify the SMA at its origin and in the distal part, to guide the plane of uncinate dissection. This video demonstrates the combination of the posterior and right medial SMA-first approach along with triangle clearance during robotic pancreaticoduodenectomy (RPD). The technique consisted of early dissection of SMA from the posterior aspect, by performing a Kocher maneuver using the 'posterior SMA-first approach'. The origin of the celiac artery, along with the SMA, was defined early in the surgery. During uncinate process dissection, the 'right/medial uncinate approach' was used to approach the SMA. 'Level 3 systematic mesopancreatic dissection' was performed along the SMA,3 culminating in the 'triangle operation'.2 RESULTS: The procedure was performed within 600min, with a blood loss of 150mL and no intraoperative or postoperative complications. The final histopathology report showed a moderately differentiated adenocarcinoma (pT2, pN2), with all resection margins free. The standardized technique of the SMA-first approach and triangle clearance during RPD is demonstrated in the video. Prospective studies should further evaluate the benefits of this procedure.

Conservative versus stent treatment for spontaneous isolated superior mesenteric artery dissection after the failure of initial 3 days' conservative treatment: A 10-year follow-up study.

To compare the safety and effectiveness of conservative and stent treatment for spontaneous isolated superior mesenteric artery dissection (SISMAD) patients after the failure of initial 3days' conservative treatment. All newly diagnosed SISMAD patients between 2013 and 2017 were retrospectively reviewed. After the failure of 3days' conservative treatment, all patients were recommended for stent treatment, but some patients refused to choose it. Their demographic, radiologic, and clinical data were compared. 57 patients were not improved after initial 3days' conservative treatment. Among them, 19 patients were chose to receive stent placement and 38 patients were continually treated with conservative treatment. The median follow-up time was 92.0 (range 62.7-120.4) months. There were no bowel ischemia and arterial rupture. No significant difference was observed in clinical complete recovery (Conservative 31/38 vs Stent 12/19, p =.19) and hospitalization time (Conservative 8.3 ± 1.7days vs Stent 7.2 ± 1.5days, p =.59) between conservative and stent treatment groups. Significant statistical differences were found in radiological complete remodeling (6/38 vs 16/19, p < .01) and hospitalization expense (8662 ± 2886 China Yuan vs 32,935 ± 11,767 China Yuan, p < .01) between these two groups. Although undergoing the failure of initial 3days' conservative treatment, continue conservative treatment still is safe and effective for SISMAD patients. Stent placement could be chosen as an alternative treatment, especially for patients potentially with bowel ischemia or arterial rupture.

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

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

Factors associated with false lumen changes in patients with superior mesenteric artery dissection

Background: False lumen changes (FLCs) are the main reference for the prognosis judgment and treatment plan selection for type IIa superior mesenteric artery dissection (SMAD). Methods: For this retrospective study, 55 patients with symptomatic type IIa SMAD were included. Computational fluid dynamics (CFD) analysis was used to explore the hemodynamic basis of FLCs. Correlation and multiple linear regression analyses were performed to identify clinical, morphological and hemodynamic factors associated with FLCs. Results: The FLCs of patients with successful conservative treatment ( n = 29) are significantly higher than those with failed conservative treatment ( n = 26) (58.5 ± 21.1% vs 10.9 ± 17.4%, p &lt; 0.0001). Positive correlations were seen between FLCs and the morphological parameters false lumen length (FLL)/dissection entrance length (DEL) and FLL. In terms of hemodynamic parameters, negative correlations were seen between FLCs and time-averaged wall shear stress (TAWSS), vorticity, and high areas of TAWSS and vorticity, whereas positive correlations were seen between FLCs and oscillatory shear index (OSI), relative residence time (RRT), and high areas of OSI and RRT. Multiple linear regression analysis identified symptom duration (odds ratio [OR], 0.93; 95% CI, 0.91–0.96; p &lt; 0.0001), FLL/DEL (OR, 1.30; 95% CI, 1.01–1.67; p = 0.044), and high RRT area (OR, 2.03; 95% CI, 1.48–2.78; p &lt; 0.0001) as predictors of FLCs. Conclusion: The clinical predictor symptom duration, morphological factor FLL/DEL, and the hemodynamic factor high RRT area can serve as predictors of FLCs in patients with symptomatic type IIa SMAD.

Non-Contrast Magnetic Resonance Imaging of Isolated Superior Mesenteric Artery Dissection.

Non-Contrast Magnetic Resonance Imaging of Isolated Superior Mesenteric Artery Dissection.

Retraction: Isolated Superior Mesenteric Artery Dissection After Methamphetamine Use: A Rare Adverse Effect.

[This retracts the article DOI: 10.7759/cureus.19551.].

Case Series on Double-Barrel Stenting for the Renal Arteries Associated With Fenestrated Repair (FEVAR) of Complex Anatomy Aortic Aneurysms.

The double-barrel stenting (DBS) is a technique in which 2 parallel stents are simultaneously deployed through the same reinforced fenestration, into 2 adjacent target vessels. Prior reports describe the application of this technique for the treatment of superior mesenteric artery dissection with aneurysmal degeneration, coronary artery bifurcations, aortic arch branches, and intracranial aneurysms. The DBS technique is particularly useful in the context of fenestrated repair (FEVAR) of complex anatomy aortic aneurysms when the origin of visceral arteries branch off the aorta very close to each other or present early branches. We herein describe a case series including 7 patients who underwent a FEVAR procedure for thoracoabdominal and juxtarenal aortic aneurysms in which the presence of accessory renal arteries (ARA) or early renal branches was the reason for the application of this technique. Technical success was 100% and all stents were patent in the last follow-up CT scan (follow-up range: 1.8-62.8 months). There was only 1 small endoleak from indetermined source potentially related to the DBS, but the aneurysm sac decreased in size during follow-up and no secondary intervention was needed. Therefore, the DBS technique is a viable option for the incorporation of ARA or early renal branches to a fenestrated repair of aortic aneurysms with complex anatomy.

Isolated superior mesenteric artery dissection as a cause of abdominal pain

Isolated superior mesenteric artery dissection as a cause of abdominal pain

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

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. 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. 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. 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.

Sequential Multiple Visceral Artery Dissection within a Short Time, without Aortic Dissection.

A 65-year-old Japanese man without medical history presented with sudden onset lower abdominal pain to our emergency department. Contrast-enhanced computed tomography (CT) revealed dissections of the inferior mesenteric artery and left renal artery with false lumen thrombosis without aortic dissection. He was immediately hospitalized, and conservative treatment was administered. However, on the third-day post-onset, the patient reported severe upper abdominal pain and contrast-enhanced CT showed a new superior mesenteric artery dissection. He continued to receive conservative treatment, and his symptoms improved. He was discharged after ten days of hospitalization.

Laparoscopic dissection around the superior mesenteric artery by left posterior approach during pancreaticoduodenectomy.

In pancreaticoduodenectomy (PD), the approach to superior mesenteric artery (SMA) is a critical process that supports adequate surgical margins and radicality for pancreatic tumors. In most of the reports on laparoscopic PD, the right-sided approach in which the jejunum is pulled out to the right side for peri-SMA dissection is used, since the left side of the SMA is difficult to dissect, and the only way to do this is to dissect the vein first. We devised a method to simplify and safely perform peri-SMA dissection by reversing the process, starting from the left side of the SMA. The first step involves the mobilization of the pancreatic head, which allows for rotation around the SMA. The second step involves the dissection of the left side of the SMA and transection of the jejunum. The key point is to change the incision line between the anterior and posterior mesojejunum. The third process includes the inferior pancreatoduodenal artery (IPDA) and first jejunal artery (J1A) dissection, which can be easily performed from the left side because the SMA rotates by simply continuing the dissection along the previously exposed SMA, and the IPDA/J1A are safely dissected at the root because they are drawn to the left side. The remaining processes are performed on the right side. This method was performed in 16 cases, and in most cases IPDA/J1A were divided from the left side. The technique for SMA dissection from the left posterior side was described with illustrations and video. Our method allows safe oncologic dissection around SMA avoiding anatomical misorientation during laparoscopic PD.

Superior mesenteric artery-related outcomes in fenestrated/branched endografting for complex aortic aneurysms.

Early/follow-up durability of superior mesenteric artery (SMA) stent-grafts is crucial after fenestrated/branched endografting (FB-EVAR) in complex abdominal aortic aneurysms (CAAAs) and thoracoabdominal aortic aneurysms (TAAAs). The study aimed to report early/midterm outcomes of SMA incorporated during FB-EVAR procedures. FB-EVAR procedures performed between 2016 and 2021 in a single institution were reviewed. Anatomical SMA characteristics were analyzed. The SMA configuration was classified into three types according to the angle between the SMA main trunk and the aorta: (A) perpendicular, (B) downward, and (C) upward. SMA-related technical success (SMA-TS: cannulation and stenting, patency at completion angiography without endoleak, stenosis/kinking, dissection, bleeding, and 24-h mortality) and SMA-adverse events (SMA-AEs: one among bowel ischemia, stenosis, occlusion, endoleak, reinterventions, or SMA-related mortality) were assessed. Two hundred FB-EVAR procedures with SMA as the target artery were performed. The indication for FB-EVAR was CAAAs and TAAAs in 99 (49%) and 101 (51%) cases, respectively. The SMA configuration was A, B, and C in 132 (66%), 63 (31%), and 5 (3%) cases, respectively. SMA was incorporated with fenestrations and branches in 131 (66%) and 69 (34%) cases, respectively. Directional branch (P < .001), aortic diameter ≥35 mm at the SMA level (P < .001), and ≥2 SMA bridging stent-grafts (P = .001) were more frequent in TAAAs. Relining of the SMA stent-graft with a bare metal stent was necessary in 41 (21%) cases to correct an acute angle between the stent-graft and native artery (39), stent-graft stenosis (1), or SMA dissection (1). Relining was associated with type A or C SMA configuration (OR: 17; 95% CI: 1.8-157.3; P = .01). SMA-TS was achieved in all cases. Overall, 15 (7.5%) patients had SMA-AEs [early: 9 (60%), follow-up: 6 (40%)] due to stenosis (2), endoleak (8), and bowel ischemia (5). Aortic diameter ≥35 mm at the SMA level was an independent risk factor for SMA-AEs (OR: 4; 95% CI: 1.4-13.8; P = .01). Fourteen (7%) patients died during hospitalization with 10 (5%) events within the 30-postoperative day. Emergency cases (OR: 33; 95% CI: 5.7-191.3; P = .001), peripheral arterial occlusive disease (OR: 14; 95% CI: 2.3-88.8; P = .004), and bowel ischemia (OR: 41; 95% CI: 1.9-87.9; P = .01) were risk factors for 30-day/in-hospital mortality. The mean follow-up was 32 ± 24 months; estimated 3-year survival was 81%, with no case of late SMA-related mortality or occlusion. The estimated 3-year freedom from overall and SMA-related reinterventions was 74% and 95%, respectively. SMA orientation determines the necessity of stent-graft relining. Aortic diameter ≥35 mm at the SMA level is a predictor of SMA-AEs. Nevertheless, SMA-related outcomes of FB-EVAR are satisfactory, with excellent technical success and promising clinical outcomes during the follow-up.

Open repair of symptomatic superior mesenteric artery dissection.

Open repair of symptomatic superior mesenteric artery dissection.

Dual-Lumen Stenting of Dissected Superior Mesenteric Artery During Fenestrated Branched Endovascular Repair of a Post-dissection Thoracoabdominal Aortic Aneurysm.

Long-segment aortic branch dissections have been considered a relative contraindication for fenestrated-branched endovascular aneurysm repair (FB-EVAR). This case report describes a technique of dual-lumen stenting of a fully-dissected superior mesenteric artery (SMA) to preserve patency of the true and false lumens during FB-EVAR. A 67-year-old man presented with a 6.0 cm extent III chronic post-dissection thoracoabdominal aortic aneurysm. The patient had highly-complex anatomy including dissection of the entire SMA. The true and false lumens of the dissected SMA were noted to be supplying different branches, requiring preservation of both lumens. The patient underwent a staged physician-modified FB-EVAR. A modified endograft containing 5 fenestrations and 1 branch cuff was introduced and the celiac, true-lumen SMA, and 3 renal arteries were sequentially catheterized using staggered deployment of the modified endograft. The false lumen SMA stent was catheterized via the branch cuff. Molded parallel grafting ("eye-of-the-tiger") technique was used to achieve double D configuration between the true and false lumens of the SMA. This case demonstrates feasibility of dual-lumen stenting to incorporate dissected target vessels during FB-EVAR while preserving flow to both the true and false lumens and the second-order branches they supply. We report a novel technique that allows incorporation of branch vessels affected by long segment dissection during fenestrated branched endovascular aortic repairs. This has potential advantage of preserving flow to all secondary branches of the dissected target vessels, while reducing the risk of type Ic endoleak.

Insights into acute mesenteric ischaemia: an up-to-date, evidence-based review from a mesenteric stroke centre unit.

Radiologists play a central role in the diagnostic and prognostic evaluation of patients with acute mesenteric ischaemia (AMI). Unfortunately, more than half of AMI patients undergo imaging with no prior suspicion of AMI, making identifying this disease even more difficult. A confirmed diagnosis of AMI is ideally made with dynamic contrast-enhanced CT but the diagnosis may be made on portal-venous phase images in appropriate clinical settings. AMI is diagnosed on CT based on the identification of vascular impairment and bowel ischaemic injury with no other cause. Moreover, radiologists must evaluate the probability of bowel necrosis, which will influence the treatment options.AMI is usually separated into different entities: arterial, venous, non-occlusive and ischaemic colitis. Arterial AMI can be occlusive or stenotic, the dominant causes being atherothrombosis, embolism and isolated superior mesenteric artery (SMA) dissection. The main finding in the bowel is decreased wall enhancement, and necrosis can be suspected when dilatation >25 mm is identified. Venous AMI is related to superior mesenteric vein (SMV) thrombosis as a result of a thrombophilic state (acquired or inherited), local injury (cancer, inflammation or trauma) or underlying SMV insufficiency. The dominant features in the bowel are hypoattenuating wall thickening with submucosal oedema. Decreased enhancement of the involved bowel suggests necrosis. Non-occlusive mesenteric ischaemia (NOMI) is related to impaired SMA flow following global hypoperfusion associated with low-flow states. There are numerous findings in the bowel characterised by diffuse extension. An absence of bowel enhancement and a thin bowel wall suggest necrosis in NOMI. Finally, ischaemic colitis is a sub-entity of arterial AMI and reflects localised colon ischaemia-reperfusion injury. The main CT finding is a thickened colon wall with fat stranding, which seems to be unrelated to SMA or inferior mesenteric artery lesions. A precise identification and description of vascular lesions, bowel involvement and features associated with transmural necrosis is needed to determine patient treatment and outcome.

Isolated Superior Mesenteric Artery Dissection following Blunt Trauma: A Case Report

AbstractIsolated superior mesenteric artery dissection (ISMAD) is rare, with symptoms ranging from asymptomatic to acute intestinal ischemia. Risk factors for ISMAD include hypertension, atherosclerosis, abnormal elastic fibers, and pregnancy. In the present case, blunt trauma, which has not been previously reported, was suggested as a risk factor. A 46-year-old man was brought to the emergency room after he was found unconscious after a motor vehicle collision. At presentation, he had no abdominal symptoms; however, on the fourth day of admission, he presented with severe abdominal pain and vomiting. A contrast-enhanced computed tomography scan revealed an ISMAD with associated intestinal ischemia and necrosis; hence, emergency surgery was performed. Herein, we report a case of ISMAD caused by blunt abdominal trauma.

Value of CT angiography in diagnosis and classification of spontaneous isolated superior mesenteric artery dissection and evaluation of its clinical symptoms

Value of CT angiography in diagnosis and classification of spontaneous isolated superior mesenteric artery dissection and evaluation of its clinical symptoms