Many different medical conditions can raise your risk of a splenic artery aneurysm. These include: Arterial hypertension (high blood pressure). Atherosclerosis. Brain aneurysm. Cirrhosis of the liver. Connective tissue diseases including Marfan syndrome. Diabetes. Endocarditis. Fibromuscular dysplasia (FMD). Granulomatosis with polyangiitis (GPA, formerly called Wegener’s). Liver transplantation. Polyarteritis nodosa (PAN). Portal hypertension. Vasculitis.