A safe seal: controlled flow arrest with dual balloon protection for embolisation of a large spontaneous splenic arteriovenous fistula—a case report

BACKGROUND: Splenic artery aneurysm (SAA) with splenic arteriovenous fistula (SAVF) is rare. Endovascular embolisation offers a minimally invasive, spleen-preserving alternative to surgery, particularly in patients with connective tissue disorders. This case report describes a technically challenging proximal SAA with high-flow SAVF successfully treated using dual-balloon-assisted coil and N-butyl cyanoacrylate (NBCA) glue embolisation, with special consideration for vascular Ehlers-Danlos syndrome (vEDS). CASE PRESENTATION: A 28-year-old short-statured woman with micrognathia had computed tomography (CT) showing a partially thrombosed proximal SAA and early arterial-phase enhancement of portomesenteric veins. Given her young age and constitutional features, an underlying connective-tissue vasculopathy such as vEDS was suspected. Dual-balloon flow control was achieved using a 6 × 15 mm Eclipse balloon at the hepatic-coeliac bifurcation (arterial inflow control) and a 12 × 40 mm Mustang balloon in the splenic vein (venous outflow control), followed by dense coil packing and controlled NBCA injection. Post-embolisation angiography and follow-up CT demonstrated exclusion of the aneurysm-fistula complex with preserved hepatic and portal venous flows and viable splenic parenchyma. CONCLUSION: Dual-balloon-assisted coil and N-butyl cyanoacrylate (NBCA) embolisation enables precise, controlled flow arrest in high-flow SAA-SAVF, minimising non-target embolisation. This case highlights its value as a safe, spleen-preserving, and durable option-particularly relevant in patients with suspected connective-tissue disorders such as vEDS, where arterial fragility mandates meticulous endovascular technique. LEVEL OF EVIDENCE: 4 (Case Report).