Arterioportal fistula combined with portal vein aneurysm

A 45-year-old woman presented to our department with a two-day history of vomiting blood and intermittent abdominal pain over the past month. Laboratory tests revealed a low haemoglobin level of 67 g/L, and she had no history of abdominal trauma or hepatitis B.

The contrast-enhanced CT scan revealed arterial-phase enhancement of the portal vein, with a cystic protrusion measuring approximately 84x75x58 mm communicating with the portal vein via a narrow neck (at the confluence of the superior mesenteric vein and splenic vein) (Figures 1a, 1b and 1c). The three-dimensional reconstruction revealed a substantial mass situated anteriorly to the portal vein (Figure 1d). Furthermore, the CT scan revealed a decrease in hepatic volume, significant ascites enveloping the liver, and DSA angiography illustrated blood perfusion originating from a branch of the celiac artery and superior mesenteric artery (SMA) directly entering the portal vein via the cystic protrusion (Figures 2a, 2b and 2c).

Arterioportal fistula with portal vein aneurysm is characterised by an aberrant arterioportal connection and concomitant portal vein dilation. In healthy individuals, the portal vein diameter typically exceeds 15 mm, whereas in patients with liver-related conditions, it can exceed 19 mm [1,2]. This situation results in the direct shunting of arterial blood into the portal vein system, while the abnormal dilation of the portal vein exacerbates the haemodynamic disturbances within the portal system.

The aetiology of arterioportal fistula combined with portal vein aneurysm is multifaceted, encompassing congenital anomalies, abdominal trauma, liver biopsies, and malignant tumours [1,3–5]. Portal hypertension is a typical clinical manifestation of this disease, often presenting symptoms such as acute upper gastrointestinal bleeding, abdominal pain, diarrhoea, and ascites [1,6].

Imaging examinations are crucial for diagnosing the disease, allowing clinicians to visualise the hepatic vascular structure and detect arterioportal fistulas and portal vein aneurysms. In enhanced CT/MRI scans, arteriovenous fistulas may manifest as arterial phase opacification of the portal vein and persistent opacification in the portal vein phase, while portal vein aneurysms can be recognised as locally dilated abnormal structures within the portal vein.

Due to the presence of narrow channels connecting the portal vein aneurysm to the portal vein, we opted for endovascular intervention therapy utilising Amplatzer Vascular Plug II (AVP II) (Abbott) and n-Butyl cyanoacrylate (NBCA) glue (B. Braun). In terms of endovascular intervention therapy, with right common femoral artery access, a 5F sheath was positioned, and angiography of the celiac artery was performed during the procedure if necessary; we used a 6F RDC sheath (Cook Medical) to establish the embolisation access with the right portal vein. Six AVP II devices were deployed via the portal vein access to occlude the portal vein aneurysm, with an additional AVP II strategically placed to seal off the narrow channel between the aneurysm and the portal vein, thereby preventing the retrograde flow of tissue glue into the liver and effectively reducing portal vein blood flow and pressure (Figure 3). A microcatheter was inserted into the portal vein aneurysm and embolised the aneurysm with NBCA glue (Figure 3).

A postoperative follow-up examination at ten months demonstrated hepatic volume enlargement, diminution of portal vein aneurysm, and resolution of ascites (Figures 4a and 4b).

Currently, there is no standard treatment protocol for arterioportal fistula combined with portal vein aneurysm. Asymptomatic patients are recommended for follow-up observation, while symptomatic patients should undergo timely surgical or endovascular intervention therapy [1,7].

Overall, endovascular intervention therapy using AVP II in combination with NBCA glue may be a safe and effective method for treating arterioportal fistula combined with portal vein aneurysm. However, further investigation and research are still needed to improve treatment strategies for similar conditions.

Written informed patient consent for publication has been obtained.