Visceral artery aneurysms - classification, diagnosis and treatment

Two-Stage Endovascular Treatment of a Traumatic Pseudoaneurysm of Superior Mesenteric Artery Branch in a Soldier After a Military Combat Mission

Aneurysms and pseudoaneurysms of the visceral arteries are a rare pathology with a prevalence of 0.1-2% in the general population, most common in men. Despite low prevalence, visceral aneurysms pose a significant threat to the patient's health and life; a ruptured superior mesenteric branch aneurysm carries mortality rates of 10-25% and up to 30-90%. This article presents a case of a 50-year-old former active duty soldier and veteran of a military combat mission in Afghanistan, during which he sustained a traumatic injury resulting from a mine explosion under a vehicle. After completing the mission and returning home, the patient developed abdominal pain. The diagnosis made in the general surgery department of the district hospital was upper gastrointestinal obstruction and aneurysmal rupture of the superior mesenteric branch with inflammatory infiltration of the pancreatic-intestinal area. The patient underwent emergency gastrointestinal anastomosis and Braun enteroenterostomy. The aneurysm was not resected. One month later, the patient underwent a follow-up abdominal angiotomography, which revealed an approximately 20-mm aneurysm of a branch of the superior mesenteric artery and celiac artery subocclusion (Dunbar syndrome) with extensive collateral circulation. A diagnosis of pseudoaneurysm/traumatic aneurysm was made, and the patient was referred to a vascular surgery center for endovascular treatment. Following CT angiography, a decision was made to perform a two-stage endovascular repair. The first stage was a bridge therapy aimed to release celiac artery subocclusion with a stent; after 3 weeks, pseudoaneurysm embolization was performed. The decision to use two-stage endovascular treatment was attributable to the risk of gastrointestinal ischemia that might result from intraoperative technical difficulties and complications, coil dislocation, and thrombosis of the superior mesenteric artery or its branch; the coexisting subocclusion of the celiac artery was also considered. The patient was discharged in good condition and returned to normal everyday activities. He also continued follow-up appointments with a vascular surgeon. An angiotomography performed at 1 year of endovascular treatment confirmed good effects of the embolization procedure and coagulation of the aneurysm. Visceral aneurysms are a rare vascular pathology but are associated with significant morbidity and mortality rates. The incidence of ruptured aneurysms is probably underestimated as some patients may be operated on for acute abdominal symptoms, e.g., bowel obstruction.

Promising Novel Therapies in the Treatment of Aortic and Visceral Aneurysms

Aortic and visceral aneurysms affect large arterial vessels, including the thoracic and abdominal aorta, as well as visceral arterial branches, such as the splenic, hepatic, and mesenteric arteries, respectively. Although these clinical entities have not been equally researched, it seems that they might share certain common pathophysiological changes and molecular mechanisms. The yet limited published data, with regard to newly designed, novel therapies, could serve as a nidus for the evaluation and potential implementation of such treatments in large artery aneurysms. In both animal models and clinical trials, various novel treatments have been employed in an attempt to not only reduce the complications of the already implemented modalities, through manufacturing of more durable materials, but also to regenerate or replace affected tissues themselves. Cellular populations like stem and differentiated vascular cell types, large diameter tissue-engineered vascular grafts (TEVGs), and various molecules and biological factors that might target aspects of the pathophysiological process, including cell-adhesion stabilizers, metalloproteinase inhibitors, and miRNAs, could potentially contribute significantly to the treatment of these types of aneurysms. In this narrative review, we sought to collect and present relevant evidence in the literature, in an effort to unveil promising biological therapies, possibly applicable to the treatment of aortic aneurysms, both thoracic and abdominal, as well as visceral aneurysms.

Technical considerations of endovascular management of true visceral artery aneurysms

BACKGROUND

True visceral artery aneurysms are potentially complex to treat but with advances in technology and increasing interventional radiology expertise over the past decade are now increasingly the domain of the interventional radiologist. BODY: The interventional approach is based on localization of the aneurysm and identification of the anatomical determinants to treat these lesions to prevent aneurysm rupture. Several different endovascular techniques are available and should be selected carefully, dependent on the aneurysm morphology. Standard endovascular treatment options include stent-graft placement and trans-arterial embolisation. Different strategies are divided into parent artery preservation and parent artery sacrifice techniques. Endovascular device innovations now include multilayer flow-diverting stents, double-layer micromesh stents, double-lumen balloons and microvascular plugs and are also associated with high rates of technical success.

CONCLUSION

Complex techniques such as stent-assisted coiling and balloon-remodeling techniques are useful techniques and require advanced embolisation skills and are further described.

Splenic artery aneurysm in pregnancy: A systematic review

OBJECTIVE

Splenic artery aneurysms (SAA) are associated with significant maternal and fetal mortality when ruptured in pregnancy. However, there is no consensus on the optimal obstetric management of both ruptured and asymptomatic SAA. We aimed to evaluate risk factors, presentation, investigation, and management of SAA in pregnancy and puerperium.

METHODS

MEDLINE, EMBASE, and Scopus were screened from January 2000 to October 2020 using keywords related to pregnancy and SAA. Articles on ruptured and unruptured SAA in pregnancy until 6 weeks postpartum were considered. Data were extracted by two independent reviewers. Quantitative analysis and narrative synthesis were used.

RESULTS

Seventy-five ruptured and nine unruptured SAA cases were included. Mean age was 31.1 ± 5.2 years, of which 47 (64.4%) were multiparous and 46 (54.8%) presented in their third trimester, largely with epigastric and left-sided abdominal pain. The double-rupture phenomenon of delayed blood loss and symptoms was noted in 11 (14.7%); 60 (70.7%) underwent preoperative imaging. Mean SAA size was 23.0 ± 13.6 mm. Ruptured SAA were primarily managed by laparotomy (61, 81.3%) typically with splenectomy,  and unruptured SAA by embolization or laparotomy. There was no mortality in unruptured SAA, but significant mortality on rupture (19, 25.7% maternal; 36, 50.0% fetal).

CONCLUSION

Given their predisposition and high mortality in pregnancy, it is crucial that SAAs are promptly diagnosed and managed, requiring increased obstetrician awareness.

Evolving Diagnostic and Therapeutic Options for Visceral Artery Aneurysms

BACKGROUND

Visceral artery aneurysms (VAAs) are associated with a very high mortality rate when ruptured and may present as a surgical emergency. Due to their rarity and varying pathophysiology, literature concerning the optimal management of VAAs is limited. This review evaluates the evolving management options for VAAs with a focus on open and endovascular repair.

METHODS

A combination of databases including OVID, PubMed and Medline were used to perform a literature search. Search terms employed include 'visceral artery aneurysms', 'angiography', '3D-volumetric rendering', 'management', 'open repair' and 'endovascular repair', amongst others.

RESULTS

3D modelling in conjunction with existing diagnostic techniques, such as computed tomography and angiography, may improve diagnostic sensitivity. The literature surrounding operative management of VAAs highlights the effectiveness of endovascular repair for anatomically suitable aneurysms. Advances in endovascular technologies may expand the type and number of aneurysms amenable to catheter-based treatment approaches. For aneurysms not amenable to endovascular treatment, or those with an emergency indication, open repair remains an appropriate management choice.

CONCLUSION

Although rare, VAAs pose a high mortality risk, especially when ruptured. Practical limitations that restrict current operative approaches may be overcome by recent developments including novel neurointerventional techniques that have been applied in VAA management.

Cirsoid aneurysm rupture of the splenic artery as a rare cause of fatal hemoperitoneum

Cirsoid aneurysms are rare arteriovenous malformations without any capillaries interposed and almost always observed in the scalp region. These types of aneurysms are so-called "cirsoid" because of their serpiginous appearance. In this report, the authors present the first case of a lethal spontaneous rupture of a cirsoid aneurysm of the splenic artery, which could be diagnosed only by post-mortem histologic examination. The victim was a 70-year-old man who was suddenly found dead in bed while he was hospitalized and waiting for a scheduled cardiac surgery. A forensic autopsy was ordered due to the suspicion that the man's death could have been related to medical malpractice. An accurate autopsy and a complete forensic histologic examination could clarify the cause of death, which was identified in the spontaneous rupture of a cirsoid aneurysm of the splenic artery. The case is intended to be used as source data for similar forensic cases, where the cause of a massive hemoperitoneum is difficult to be identified.

Clinical efficacy of coil embolization in treating pseudoaneurysm post-Whipple operation

The present study aimed to evaluate the clinical efficacy and safety of angiography and coil embolization for pseudoaneurysm post-pancreatoduodenectomy (PD). A total of 17 patients with gastrointestinal or abdominal hemorrhage after PD were included in the present study. Angiography was performed on the celiac artery, common hepatic artery, splenic artery, gastroduodenal artery and superior mesenteric artery to determine the size of the pseudoaneurysm, the parent artery and its collateral branches. A variety of embolization techniques have been applied to embolize pseudoaneurysm, including the sac packing technique, proximal embolization, exclusion technique and sandwich technique. Different techniques with coils were used for embolization and the clinical effects of embolization were analyzed. A total of 18 pseudoaneurysms were identified in 17 patients. In 2 patients, severe technical complications occurred, including migration of the coil and rupture of pseudoaneurysm, and one of them died, which may have been associated with this complication. No serious clinical complications were observed in the other patients. A total of 7 patients had mild clinical complications, including mild abdominal and dorsal pain, which were alleviated after symptomatic management. A total of 15 patients with definite pseudoaneurysm were successfully embolized without re-bleeding and complications. The clinical success rate was 94.1% (16/17). In conclusion, a variety of embolization techniques may be applied for the treatment of pseudoaneurysm after PD, which have high technical and clinical success rates and small trauma. It is recommended in emergency situations, but care should be taken to avoid serious technical complications.

Celiacomesenteric trunk associated with superior mesenteric artery aneurysm: A case report and review of literature

In rare cases, the celiac artery and the superior mesenteric artery arise from a common origin known as a common celiacomesenteric trunk. Celiac trunk stenosis or occlusion has been reported to accompany this anatomical aberrancy. Even rarer, are aneurysms associated with this common celiacomesenteric trunk. In general, visceral artery aneurysms are uncommon. We hereby present a 39-year-old female patient with a 1-month history of mild diffuse abdominal pain, with an incidental finding of superior mesenteric artery aneurysm on abdominal ultrasound. Subsequent contrast-enhanced computed tomography revealed severe narrowing of the celiac trunk and saccular aneurysmal dilatation of the superior mesenteric artery. Coil embolization of the aneurysm was performed, while maintaining persistent flow in the superior mesenteric artery and celiacomesenteric trunk. Visceral artery aneurysms are increasingly being identified incidentally with improvement in imaging techniques. The question lies whether to treat these aneurysms or observe. No universal guidelines exist regarding that matter, but the decision to intervene is made based on aneurysm location, size, and patient characteristics.