Fankhauser et al. (2011) reported a large series of VAAs and pseudoaneurysms treated by minimally invasive techniques. Minimally invasive management was attempted in 185 aneurysms in 176 patients. The aneurysms were mainly located in the splenic artery (34%), the hepatic artery (30%), the gastroduodenal artery (15%), and in the pancreaticoduodenal artery (8.6%). The most commonly used technique was coiling (162 aneurysms). It was the sole interventional technique employed in 144 (78%) of cases. Initial treatment was successful in 182 (98%) aneurysms. During repeat imaging within the first 30 days, persistent aneurysm flow was seen in five (3%) aneurysms, and subsequent successful reintervention was undertaken. There were 11 deaths in the initial 30-day period leading to an overall 30-day mortality rate of 6.2%. Aneurysm related 30-day mortality rate was 3.4%. Neither aneurysm growth nor aneurysm rupture was observed in any patient during the follow-up period (mean, 78 weeks). Major splenic infarction occurred in three of 33 patients (9%) with no underlying liver disease and normal splenic volume and in seven of 14 patients (50%) with portal hypertension.

A single-center experience with elective coil embolization of 63 splenic artery aneurysms (SAA) in 50 patients was presented by Patel et al. (2012). Ninety-eight percent of procedures were technically successful at thrombosing the aneurysm at the time of procedure. Neither aneurysm growth nor aneurysm rupture was observed in any patient during the follow-up period (mean, 78 weeks). There were no major adverse events. Major splenic infarction occurred in three of 33 patients (9%) with no underlying liver disease and normal splenic volume and in seven of 14 patients (50%) with portal hypertension. Etezadi et al. (2011) presented early and midterm results of endovascular treatment of 41 visceral and renal artery aneurysms in 40 consecutive patients. The series included 30 true aneurysms and 11 pseudoaneurysms in renal (n = 17), splenic (n = 13), hepatic (n = 4), celiac (n = 4), gastroduodenal (n = 2), and middle colic (n = 1) arteries. The most commonly used technique (93%) was coil embolization with (15%) or without (78%) other endovascular agents. Technical success rate was 98%, with no periprocedural mortality. Mean imaging follow-up was 11.7 months. End-organ partial infarction was detected in six patients, with no clinical evidence of organ insufficiency. Koganemaru et al. (2014) evaluated the outcomes of coil embolization of true visceral artery aneurysms in 23 patients. Complete aneurysmal occlusion was determined in 22 patients (96%) on follow-up MR angiography (mean follow-up period, 18 months). An asymptomatic localized splenic infarction was confirmed in one patient (4%). The correlation between packing density and the incidence of coil compaction or recanalization of VAAs after coil packing was evaluated by Yasumoto et al. (2013). Coil packing was performed for 46 true visceral aneurysms. The mean follow-up period was 37 months. Recanalization occurred in 12 aneurysms (26%). In aneurysms with a packing density of at least 24%, no compaction or recanalization occurred. Balderi et al. (2012) used an endovascular approach to treat 30 patients with 31 aneurysms (n = 18) or pseudoaneurysm (n = 13) of the splenic (n = 11), hepatic (n = 6), renal (n = 5), pancreaticoduodenal (n = 3), left gastric (n = 2), gastroduodenal (n = 1), rectal (n = 1) or middle colic (n = 1) arteries and the coeliac axis (n = 1). 26/31aneurysms were treated with metal coils. In all aneurysms and pseudoaneurysms immediate exclusion was obtained. In four patients with aneurysm and in four with pseudoaneurysm, parenchymal ischaemia occurred; one was treated with surgical splenectomy. One patient with pseudoaneurysm of the coeliac axis died 10 days later because of new bleeding. During follow-up (12 months), all aneurysms and pseudoaneurysms remained excluded.

Dorigo et al. (2016) performed 26 consecutive elective endovascular interventions for VAAs. The site of aneurysm was splenic artery in 17 patients. Interventions consisted in coiling in 19 cases; in 4 patients a covered stent was placed, whereas the remaining 3 patients had a multilayer stent. Technical success was 89%. There were no perioperative deaths. Median duration of follow-up was 18 months. During follow-up, 1 aneurysm-unrelated death occurred. Freedom from aneurysm-related complications at 2 years was 72.9%. Nineteen consecutive patients with a total of 19 visceral artery aneurysms were electively (n = 9) or emergently (n = 10) treated with a variety of stent-grafts by Künzle et al. (2013). The in-hospital mortality rate was 11% (n = 2). CT angiography (CTA) demonstrated stent-graft patency at a mean follow-up of 28 months in 9 of 11 patients (82%) and thrombosis in two patients (one with a splenic and one with a renal artery stent-graft). These events were asymptomatic. Gandini et al. (2016) excluded 10 renal artery aneurysms (RAA) in 9 patients using covered stents. CTA up to 24 months after ER demonstrated patency of the cover stents, absence of endoleaks and re-stenosis in all patients.

Roberts et al. (2015) reviewed all patients undergoing emergency treatment (endovascular or surgical) of a symptomatic VAA in a 5-year period. Patients with RAA were not included in this study. Symptomatic VAAs were defined as those presenting with gastrointestinal haemorrhage (haematemesis, malaena, or haemobilia) and peritoneal or retroperitoneal haemorrhage due to the presence of the VAA. Interventional radiology was the initial treatment in all patients: endovascular procedures n = 47 and ultrasound guided percutaneous injection n = 1 (of an intrahepatic VAA). The initial success was 40 out of 48 (83%). Surgical intervention was required in two patients (4%). The 30-day mortality was eight out of 48 (17%).

Guo et al. (2016) reviewed the outcomes of symptomatic visceral artery aneurysms (SVAAs) and asymptomatic visceral artery aneurysms (ASVAAs) after endovascular treatment. In total, 27 patients with SVAA (mean diameter, 36.9 ± 15.3 mm) and 79 patients with ASVAA (mean diameter, 33.6 ± 36.1 mm) were treated. The most common intervention type was coil embolization (81%), followed by stent-assisted embolization (10%) and covered stent repair (9%). The immediate technical success rates of SVAA and ASVAA repair were 96.3% and 97.5%, respectively. The most common complication after endovascular treatment was end-organ ischemia (11.1% for SVAA vs 13.9% for ASVAA). Partial liver infarction was noted in two cases, and partial or complete splenic infarction was noted in five cases. None of these infarctions caused clinically significant complications within the first 30 days. The overall mortality rate for VAA was 6.6% (7/106), and the direct and indirect aneurysm-related mortality rate was 3.8% (4/106) during the first 30-day period and follow-up. All of the deaths occurred in the SVAA group. The median duration of follow-up was 39.1 ± 29.2 months. Twenty-two patients were lost to follow-up. There was a statistical difference in overall survival between the SVAA and ASVAA groups at 3 years (85.2% vs 97.5%).

Ghariani et al. (2013) reported long-term results of open repair of 78 VAAs in 60 patients. The aneurysms involved the coeliac trunk (30%), hepatic artery (26%), splenic artery (24%) and the mesenteric superior artery (14%). Twenty patients (33%) were symptomatic, 1 of whom presented with aneurysmal rupture (1.7%). Hospital mortality was 1.7%. Five reintervention procedures (8%) were necessary. The actuarial survival rates were 98% at 1 month and 1 year, and 97% at 5 and 10 years, respectively. The primary patency rate of the revascularizations was 98% at 1 month and 1 year, and 95% at 5 and 10 years. The authors emphasized that those results were the standard which endovascular treatment of VAAs has to match.

Hogendoorn et al. (2014) performed a systematic review of all studies describing the outcomes of splenic artery aneurysms treated with open (OR), endovascular (ER), or conservative management. They identified 1321 patients (OR n = 511 (38.7%); conservative n = 425 (32.2%); ER n = 385 (29.1%)) in 47 articles. The conservative group had fewer symptomatic patients (9.5% vs 28.7% in OR and 28.8% in ER) and fewer ruptured aneurysms (0.2% vs 18.4% in OR and 8.8% in ER). OR had a higher 30-day mortality than ER (5.1% vs 0.6%), whereas minor complications occurred in a larger number of the ER patients. ER required more reinterventions per year (3.2%) compared with OR (0.5%) and conservative management (1.2%). The late mortality rate was higher in conservatively treated patients (4.9%) as compared to OR (2.1%) and ER (1.4%) (Table 6.1). The authors concluded that splenic artery aneurysms >2 cm should be treated, given the good short-term and long-term results. ER has the best outcomes and should be the treatment of choice if the splenic artery has a suitable anatomy for endovascular repair. In addition, Hogendoorn et al. (2015) evaluated the cost-effectiveness of OR, ER, and conservative management of splenic artery aneurysms. They found ER to be the most cost-effective treatment for most patient groups with splenic artery aneurysms, independent of the sex and risk profile of the patient. ER was superior to OR, being both cost-saving and more effective in all age groups. Elderly patients (>78 years) should be considered for conservative management, based on the high costs in relation to the very small gain in health when treated with ER.