Gastrointestinal (GI) bleeding is a serious, potentially fatal condition that can occur secondarily to a variety of other conditions in the body, such as diverticulosis, angiodysplasia, portal hypertension (which can be due to cirrhotic or noncirrhotic pathologies), and splenic vein thrombosis secondary to hepatitis C virus (HCV).¹ In many patients with GI bleeding, the bleeding either resolves on its own or can be treated endoscopically. However, in many cases of lower GI hemorrhage (bleeding distal to the ligament of Treitz), profuse bleeding in the colon renders colonoscopy ineffective in identifying the source of bleeding. In such cases, a transjugular intrahepatic portosystemic shunt (TIPS) can be performed to treat the variceal hemorrhage, particularly if the varices are secondary to portal hypertension.² This is because in portal hypertension-associated GI varices, TIPS treats the underlying etiology of the GI bleed, whereas balloon-occluded retrograde transvenous obliteration (BRTO) would only exacerbate the portal hypertension (by obstructing the engorged collateral vessels). However, if a TIPS procedure is contraindicated (e.g., due to hepatic encephalopathy or a high Model for End-Stage Liver Disease [MELD] score) and/or if the varices are due to another underlying condition, BRTO has been considered the standard treatment. Nonetheless, if the patient does not have a gastrorenal or gastro splenorenal shunt, or if there is no active GI bleeding, traditional BRTO is not indicated either.³ Therefore, in instances in which the bleeding cannot be controlled endoscopically or with TIPS or BRTO, embolization of the compromised vessels is a useful technique. There are multiple strategies concerning artery embolization. The most common embolic agent used in these situations is a coil. The second strategy uses gel or liquid to block flow in the vessel. Gel/liquid embolizes more quickly than a coil, and in cases of more difficult bleeding, liquid or gel embolization may be the preferred option. N-butyl-2-cyanoacrylate (n-BCA) is a tissue adhesive agent that is commonly used to treat intracranial arteriovenous malformations.⁴ n-BCA is also bacteriostatic, and can be used to treat gastric, duodenal, esophageal, and colonic varices. Although the usage of n-BCA embolization in GI bleeding is still off-label, it is an option in the treatment of varices in the GI tract. In the case of this patient’s varices, this was the technique that was used.

The patient was a 65-year-old man who presented with a GI bleed. His past medical history included HCV cirrhosis, colonic polyps, and rectal carcinoma (with subsequent resection of the lower anterior colon, including part of the rectum). In this case, endoscopic sclerotherapy was not indicated, because the gastroenterology service was unable to visualize the lesion in which the varix was located. In light of this, a nuclear medicine-tagged red blood cell (RBC) scan was performed, along with computed tomography angiography (CTA). The tagged RBC scan showed active bleeding in the distal small intestine. Furthermore, it was thought that this was a venous bleed, because three CTA scans were all negative for arterial hemorrhage. A CT scan with contrast was also performed, which showed the varix in the distal small bowel (Fig. 1). Initially, interventional radiology received a consult for a potential TIPS procedure. The patient’s MELD score was 9, indicating that the patient was relatively low risk. However, liquid embolization was used instead of TIPS, due to two main disadvantages of TIPS—namely, the poor primary shunt patency rate (50%–60% of cases) and potential postprocedural hepatic encephalopathy.⁵ At the beginning of the procedure, an AccuStick needle (Boston Scientific Corp.) was guided directly into the right portal vein percutaneously, and a wire was then advanced through the main portal vein and into the superior mesenteric vein. Then, the needle was exchanged for an AccuStick vascular sheath, with a .035” wire subsequently guided through into the superior mesenteric vein. At this point, the AccuStick sheath was replaced with a long 5-Fr AccuStick vascular sheath. Before the therapeutic procedure, a venogram was performed and showed a patent inferior mesenteric vein and the varix (Fig. 2). At this time, there was no active bleeding. Then, a 2.4-Fr Progreat (Terumo Interventional Systems) microcatheter’s microwire was inserted coaxially in an attempt to cover the entirety of the varix, but the varix was too tortuous for this strategy. Because of this, the n-BCA liquid embolic material (in a mixture of 2:1 lipiodol to n-BCA) was then delivered through the 5-Fr Berenstein occlusion balloon catheter (Boston Scientific Corp.). The inflow vessel, the varix, and the outflow vessel were embolized, and flow control was needed to prevent distal migration of the embolic agent (Fig. 3). A subsequent venogram demonstrated no flow in the varix after embolization of the vessels. Paracentesis was also performed, with 1 L of ascites drained, to show that there were no problems after the procedure. There were no immediate complications, and the patient did well after the procedure.

Figure 1. Digital subtraction images showing a superselective angiogram of the varix arising from the distal superior mesenteric vein (arrow). Transhepatic access into the portal vein was obtained (not shown).

Figure 2. Coronal, axial, and sagittal computed tomography scans with intravenous contrast showing a prominent distal small bowel intra-luminal varix (arrows).

Figure 3. Post-N-butyl-2-cyanoacrylate embolization spot image, showing the embolic material in the inflow vessel, varix, and outflow vessel.

The informed consent was waived.

This case is an important example of when a technique other than TIPS or BRTO can be used to treat GI hemorrhage. GI bleeds occur in different locations, with different considerations for treating each. GI varices are significantly less common than esophageal varices, but they are associated with more severe bleeding and worse patient outcomes.⁶ Although endoscopic treatment can be employed for GI varices, this is not indicated in cases such as this because of an inability to properly visualize the varices. Additionally, in any cases with inactive GI bleeds (and those with high MELD scores), the disadvantages of TIPS and BRTO render these treatments unusable. These considerations demonstrate why liquid embolization was considered the best option for this patient. Although embolization is not unheard of in treating GI bleeds, liquid embolization is an off-label strategy that can play an increasing role in future treatment paradigms, especially in the upper GI tract. This is primarily due to the rich collateral vascular supply of the upper GI tract compared to the lower part of the tract (which mitigates the effect of embolization of collateral vessels). n-BCA was the preferred embolic agent in this case because of the durability of n-BCA embolization in smaller vessels, along with the rapid polymerization in the given vessel. One important (but uncommon) complication of n-BCA embolization of varices is possible migration of the monomer into the systemic venous circulation, and subsequent formation of pulmonary embolism. Therefore, it is critical that the clinician performing the embolization is proficient with using cyanoacrylate glue. In this case, the interventional radiologist who completed the procedure had over 3 years of experience in independent practice and was particularly proficient with embolic materials.

None.

The data that support the findings of this study are available from the corresponding author upon reasonable request.

No potential conflict of interest relevant to this article was reported.