Transcatheter Endovascular Therapy of a Traumatic Common Hepatic Artery Aneurysm

We present a case in which a computerized tomographic scan was initially misleading, resulting in confusion over the diagnosis and treatment of a progressively increasing pulsatile abdominal mass. Angiography further clarified the situation, and led to the diagnosis of a large aneurysm arising from the common hepatic artery. Case Report. A 62-year-old farmer presented with a palpable, pulsatile mass in the right hypochondrium and epigastrium progressively gaining in size for last 3 months. Six months prior, he had received a blunt injury to his abdomen when he was dashed by a cow in his farm house. Initially, he was treated for the fracture of three ribs on the right side of the thorax with an uneventful recovery. Three months later, he started complaining of vague abdominal pain and was treated initially for gastritis. One month later, on clinical examination a small mass was detected in the right hypochondrium which progressively increased in size; he was developing icterus, anorexia and frequent vomiting. Liver function test revealed signs of obstructive jaundice with rise in conjugated bilirubin and alkaline phosphatase. There was a mild rise in amylase and lipase, which raised the suspicion of pancreatitis. An abdominal ultrasound examination excluded any involvement of the gall bladder, but a pulsatile mass could be seen without any obvious vascular relation. A computerized tomographic scan of the abdomen diagnosed in favor of a pancreatic cyst 4.7 cm in diameter, filled with fluid (Figure 1). At this stage, the patient was seen in the department of Abdominal Surgery for an operative treatment of the cyst. However, the surgeon wanted to exclude any vascular aneurysm after considering the significant pulsation of the palpable mass, and referred the patient to the cardiac catheterization laboratory for angiography of the abdominal vessels (particularly the abdominal aorta and the celiac trunk). An abdominal aortography did not show any aneurysm in its stretch from the abdominal inlet to the bifurcation, but faint filling of a mass was noted in the right hypochondrium in the late phase of the angiography. The celiac trunk was hooked with a 6 French internal mammary artery (IMA) catheter and the initial shot of dye filled a large aneurysm on the side of the common hepatic artery (Figure 2). The splenic artery looked normal (Figure 3) and the left gastric artery was not adequately visualized. There was no proper filling of the common hepatic artery and its branches, as the whole amount of dye filled the aneurysm without giving a definite clue about its origin at this stage. A hydrophilic guidewire (Terumo Medical Corporation, Somerset, New Jersey) coiled repeatedly inside the aneurysmal sac but later found an exit along the cranial border of the aneurysm entering the intrahepatic part of the vessel. The IMA catheter was now carefully railed over the guidewire reaching inside the liver. Careful injection of dye showed a normal main hepatic artery and its intrahepatic arterial distribution, as well as a normal gastroduodenal artery and its branches (Figure 4). On further pull-back, the catheter tip fell into the aneurysmal sac, thus confirming its origin from the common hepatic artery, most likely injured during the bovine attack (Figure 7). The surgeon was not very keen to open the abdomen at this stage and the option for an endovascular approach to treatment was discussed. Although our unit has performed abdomino-vascular intervention regularly for over a decade, we did not have any previous experience in tackling a situation exactly like this. After discussing different possibilities for tackling the case and the ready availability of treatment materials in the Catheterization Laboratory, we decided to “shut the entry of blood into the aneurysm by embolizing the routes of its transport”. This approach seemed to be more practical with the following technique: 1. Transcatheter embolization of the gastroduodenal artery by injecting Drivelon® polyvinyl alcohol particles (Nycomed-Amersham Imaging, Princeton, New Jersey),2 thus blocking the route of the entry of blood from the superior mesenteric artery via the pancreaticoduodenal arcade and gastroduodenal artery. 2. Pull the catheter back to the ostium of the common hepatic artery down to its point of take-off from the celiac trunk. 3. Place a 6 mm coil at the ostium of the common hepatic artery3 to stop the entry of blood from the abdominal aorta. This would deprive the aneurysmal sac totally of its blood supply. Technically, this procedure was possible in the next crucial 20 minutes of time. The Terumo guidewire could now be manipulated into the main hepatic artery without being trapped in the aneurysmal sac. The IMA catheter was now railed over the guidewire and its tip was placed in the right hepatic artery. On careful pull-back while keeping the tip directed caudally, it fell into the ostium of the gastroduodenal artery. Because the vessel was small caliber (around 2 mm), it could be occluded by transcatheter injection of Drivelon-900 particles. The IMA catheter was then pulled back into the common hepatic artery and placed just proximal to the aneurysmal sac. After measurement of the vessel size, a 6 mm coil was selected; it was carefully pushed through the catheter with the hard end of the 0.36 Teflon-coated guidewire up to 2/3 of the catheter length, then changed to the soft end and finally pushed out of the catheter tip and deployed in the vessel. Passage of dye though the common hepatic artery stopped totally in the next 25 minutes (Figure 5). The patient was discharged five days later, and was advised to have complete bedrest. When discharged, he was still icteric with abdominal tenderness, but the mass was definitely not pulsating. The icterus disappeared after one week, but hepatic enzymes increased over the next two weeks then reverted to normal over a four-week period. Normalization of the serum bilirubin level indicated a reduction in the pressure effect on the common bile duct from the aneurysmal sac. A CT-scan was repeated once every four weeks; it showed a progressive reduction in size of the aneurysm until its diameter reduced to 1 cm after 12 weeks. The Radiologist reported that it is now filled with clots, having no free fluid (Figure 6). Clinically, the mass was not palpable any more and the patient is totally symptom-free after 13 months of clinical follow-up. Discussion. Trauma-induced aneurysm of blood vessels of the different parts of the body have been reported in the literature.4,5 This particular case, however, is different from both diagnostic and therapeutic points of view. The location of the aneurysm in the abdomen, which is known to be a “magic box”, resulted in a difficult diagnosis, particularly when a reliable diagnostic tool like the CT-scan was initially misleading. During the initial part of the angiography, the situation became more confusing when keeping the CT diagnosis in mind. The diagnosis only became clear after visualization of the distal vascular anatomy. The decision for endovascular therapy was very reasonable in an Interventional Unit with regular experience at tackling abdominal visceral vascular emergencies with the endovascular approach. An open surgical approach would have been much more time consuming, with a significantly higher risk of mortality and morbidity. Before commencing the bidirectional embolization, we discussed two other possibilities for dealing with this case: 1. Placement of a covered stent in the hepatic artery, starting from its take-off at the celiac trunk up to a point before the take-off of the gastroduodenal artery, thus isolating the aneurysm (as is done in other areas such as the aorta and the coronary arteries). This approach definitely sounds better, but this stent was not readily available in the required size and length. With this method, the hepatic arterial circulation could be maintained, but in reality we know that only 25% of the liver is dependent on the hepatic arterial supply, while the rest is met by the portal system. 2. Filling the aneurysmal sac with multiple coils. In this case, we did not have any idea of the quantity of coils required to get an optimum result. In the past, we lost a patient following rupture of a post-cholecystectomy pseudoaneurysm after filling it with three coils. The development of obstructive jaundice also confused us at the beginning of this case; this was surely due to pressure from the large aneurysm on the extrahepatic part of the bile route. Conclusion. In multiple-faculty hospitals with well-coordinated interdepartmental relationships, such relatively rare abdominal pathologies can be tackled expeditiously and safely with total success by a well experienced team practicing endovascular interventional techniques.

1. Sclafani, Ben-Menachem Y. Embolotherapy in abdominal trauma. In: Neal MP Jr., Cho S (eds). Emergency Interventional Radiology. Boston: Little, Brown. 1989: pp. 53–57. 2. Dhar A, Konar A, Sengupta D. Transcatheter therapy of intravisceral bleeding. J Invas Cardiol 2001;13:126–128. 3. Chuang VP, Wallace S, Gianturco C. A new improved coil for tapered-tip catheter for arterial occlusion. Radiology 1980;135:507–509. 4. Ross P Jr., Denny DF Jr., Baker CC. Angiographic embolization of traumatic hepatic artery pseudoaneurysm. Conn Med 1990;54:308–310. 5. Hanks SE, Pantecost MJ. Angiography and transcatheter treatment of extremity trauma. Semin Intervent Radiol 1992;9:20–25.