Successful long-term repair of hepatic artery pseudoaneurysm following liver transplantation with primary stent-grafting

Hepatic artery pseudoaneurysm is an unusual and potentially serious complication occurring after liver transplantation or major liver surgery; it could be asymptomatic, or present with nonspecific abdominal pain or massive gastrointestinal bleeding. Treatment options focus on surgical reconstruction, including resection and revascularization, or catheter-based minimally invasive endovascular treatments such as coil embolization, especially in the event of rupture and hemorrhage.1, 2 Other options include retransplantation or ligation of the hepatic artery.3, 4 Standard treatment is associated with a 69% mortality rate.3 The successful use of covered stent prosthesis to seal the aneurysm after failed embolization or acute hemorrhage has been recently described.5, 6 We report a case in which stent grafting was successfully adopted as primary treatment in an elective setting with a long-term evaluation of patency and liver function. The patient is a 47-year-old man who underwent an orthotopic liver transplant for end-stage liver disease secondary to cirrhosis from significant ethanol abuse and chronic hepatitis C. The patient underwent above the knee right leg amputation due to osteomyelitis 2 weeks prior to the transplant. The posttransplantation recovery was uneventful. During routine follow-up, 16 months posttransplantation, a spiral computed tomography scan with contrast revealed hepatic artery pseudoaneurysm arising from the common hepatic artery distal to the arterial anastomosis (Fig. 1). There was a severe stenosis of the hepatic artery associated with the pseudoaneurysm. Hepatic artery pseudoaneurysm seen in contrast-enhanced computed tomography scan. After the benefits and risks of the angiography and endovascular interventions such as angioplasty, embolization, and stent-grating were explained, a written informed consent was obtained from the patient. The right groin was prepared and draped in sterile fashion. Using the Seldinger technique, the right femoral artery was punctured and a 5-French sheath was placed into the aorta from the right femoral approach. Through the sheath, a 4-French catheter was placed in the celiac artery for celiac angiography, which showed the celiac artery, left gastric artery, and hepatic artery to be patent. There was a severe stenosis of the hepatic artery at the hilum with a pseudoaneurysm approximately 5 mm × 10 mm in size. (Fig. 2A). There was also moderate stenosis in the proximal hepatic artery immediately proximal and distal to the pseudoaneurysm. Therefore, these stenotic areas of the hepatic artery were dilated using a 2.5-mm-wide × 15-mm-long balloon catheter. Postangioplasty hepatic artery angiography showed mild to moderate improvement of the lumen of the hepatic artery at the sites of balloon angioplasties. Following the balloon angioplasty, a Jomed stent-graft (Helsingborg, Sweden), 3.5 mm in width × 19 mm in length was placed within the hepatic artery at the hilum where the pseudoaneurysm and its associated stenosis were located. Poststent grafting angiography showed successful exclusion of the pseudoaneurysm and marked improvement in the luminal diameter of the hepatic artery without significant residual stenosis (Fig. 2B). There was some spasm in the distal branches of the hepatic artery that was relieved successfully by intraarterial administration of 100 mcg nitroglycerin into the hepatic artery through the catheter. A combination of 1% solution of Lidocaine and intravenous conscious sedation was used for local anesthesia and pain management, respectively. The patient tolerated the procedure well without complications and no systemic anticoagulation was used following the procedure. Liver function tests were stable during the procedure and on the day after the procedure the liver function tests were as follows: total bilirubin, 0.9 mg/dL; aspartate aminotransferase, 20 IU/L; and alanine aminotransferase, 28 IU/L. The patient was discharged to home the following day. Hepatic artery angiography. (A) The stenosis and the aneurysm. (B) After angioplasty and aneurysm stenting, eliminating the aneurysm. Short-term evaluation of stent patency was performed at 3-month follow-up by contrast-enhanced computed tomography scan, and duplex Doppler ultrasound confirmed a patent hepatic artery and thrombosis of the aneurysm resolved by the prior stent-grafting (Fig. 3). Long-term patency was also confirmed 1 yr after the procedure by duplex Doppler ultrasound and liver function tests remained stable during the entire period of time. Follow-up computed tomography of the abdomen 6 weeks after stent grafting procedure shows patent graft and excluded and thrombosed pseudoaneurysm. The stent patency was confirmed by Doppler ultrasound. The incidence of hepatic artery pseudoaneurysm is 1 to 2% of liver transplantation patients.3 The major cause is surgical intervention to and around the hepatic artery. The mortality associated with pseudoaneurysm formation following orthotopic liver transplantation has been reported to be as high as 69%.3 Surgical revascularization and retransplantation are usually associated with a poor outcome, particularly in patients with prior poor graft function or following a complicated postoperative course.2, 3 In the case reported, the patient was diagnosed with a pseudoaneurysm approximately 1.5 yr following orthotopic liver transplantation, while he was back to normal activity and with an unremarkable liver function. This is an unusual finding, since most pseudoaneurysms are diagnosed a few months after transplantation. In this case, the diagnosis was secondary to abdominal pain and subsequent imaging of the abdomen. Surgical intervention near the hepatic vessels at long-term posttransplantation is a major procedure and can be complicated due to the presence of a large number of intraabdominal adhesions related to the previous transplant. In these instances, dissecting the vascular structures of the liver graft is associated with risk of surgically-induced biliary injury. The revascularization of the artery also presupposes a brief period of ischemia. Furthermore, there is the risk of infections and sepsis in an immunosuppressed patient. The coil embolization has the potential of causing the loss of the functioning transplanted liver if the coil migrates to the distal hepatic circulation, or it can induce hepatic artery thrombosis, and there is the possibility for aneurysm recurrence. Limited evidence suggests that stenting of hepatic artery pseudoaneurysm during acute hemorrhage can be successfully performed. This minimally invasive approach could be utilized in elective conditions; however, this has been reported only in 1 case but no short- or long-term follow-up were described.7 This prompted us to utilize elective hepatic artery stent-grafting as the primary treatment of hepatic artery pseudoaneurysm after liver transplantation and to evaluate its function over time. In our experience using this technique, we were able to successfully exclude the area of the aneurysm by stent-grafting, confirming with long-term follow-up stent patency with excellent arterial blood flow and liver function, and thereby avoiding a risky surgical intervention. In our opinion, the presence of the stent should not affect future surgical intervention. In fact, in case of failure of primary stenting, and need of surgical revascularization, the presence of the intraluminal stent might reduce the risk of hemorrhage and could assist the surgeon in locating the artery, especially if the stent is embedded in abundant scar tissue. Combining the existing reports in the literature with our experience, we suggest that stent-grafting is feasible and safe. This minimally invasive technique can be utilized as a first-line treatment option for hepatic artery pseudoaneurysm when diagnosed following liver transplantation before potential dangerous hemorrhagic complications occur and thus eliminating the need for a difficult surgical repair.