Endovascular Strategies and Outcomes for Aberrant Splenic Artery Aneurysms.

ABSTRACT

OBJECTIVES: Aberrant splenic artery aneurysms (ASAAs) located at the splenomesenteric trunk (SMT) and the celiacomesenteric trunk have a close anatomical relationship with the superior mesenteric artery (SMA). The aim of this study was to review our institutional experience of endovascular treatment for ASAAs and evaluate the long-term outcomes. METHODS: A retrospective review of patients with ASAAs who underwent endovascular treatment between December 2006 and December 2022 was performed. The demographics of the patients, aneurysm characteristics, treatment strategies, perioperative and long-term outcomes, and complications were analyzed. RESULTS: A total of 29 patients with ASAAs were endovascularly treated at our institution. The SMT variant occurred in the majority of the patients. All ASAAs were characterized by eccentric growth and extremely short inflow arteries. Only 1 patient's inflow artery of the aneurysm exceeded 1 cm in length. Thirteen patients were treated by coil embolization alone. Four patients received bare stent-assisted coil embolization. A combination of coil embolization and covered stent placement across the orifice of the aberrant splenic artery was performed in the remaining 12 cases. Coil migration into the SMA occurred in 2 patients during the operation. Technical success was achieved in all patients. With a median duration of 63 (34-101) months of follow-up, no intestinal ischemia, aneurysm-related death, aneurysm rupture, or sac enlargement occurred. Three cases of aneurysm sac reperfusion were observed, and 1 patient underwent reintervention with secondary embolization. Asymptomatic occlusion of the covered stent was detected in 1 patient at 2 years. CONCLUSIONS: Endovascular treatment is a safe, effective, and durable option for ASAAs. Inflow embolization might be difficult to achieve in ASAAs and poses a high risk of coil migration into the SMA. Long-term observation indicates that reasonable use of the covered stent could achieve reliable inflow artery exclusion in ASAAs without intestinal complications. CLINICAL IMPACT Aberrant splenic artery aneurysm (ASAA) is an extremely rare entity. This study reported a large sample size of ASAAs treated by endovascular techniques with long-term follow-up. The ASAA was characterized by an extremely short inflow artery and a close anatomical relationship with the superior mesenteric artery (SMA). Endovascular treatment is a safe, effective, and durable option for ASAAs. Inflow embolization might be difficult to achieve in ASAAs and pose a high risk of coil migration into the SMA. Long-term observation indicates that reasonable use of the covered stent could achieve reliable inflow artery exclusion in ASAAs without intestinal complications.