Endovascular Emergency Management of Hepatic Pseudoaneurism with Vascular Plug 4 System with Sacrifice of the Aneurism Nutrient Artery (Report of 2 Cases)

Pseudoaneurisms are arterial wounds that affect all layers of an artery; although very rare they are mostly lethal and most of them are iatrogenic. Herein, we present two different cases of hepatic artery pseudoaneurysms de-rived from previous surgeries which were assessed by computed tomography angiographies and consequent conservative endovascular approaches with arteriographies, posterior cannulations and the placement of Amplatzer Vascular Plug 4 (AVP 4) systems in order to treat the pseudoaneurysm. Computed control tomographies were conducted showing no later complications. The purpose of this article is to demonstrate the importance and current clinical applications of AVP in the field of interventional radiology.


Introduction
A pseudoaneurysm is an arterial wound characterized by a disruption through all the layers of an artery with the particularity of a continuous flow outside the vessel into a space contained by the surrounding tissue [1]. They may be classified as iatrogenic, infected, anastomotic, or (the most common) iatrogenic [1] [2]. Hepatic artery pseudoaneurysm is a very rare and lethal entity and is considered an acute emergency which requires an immediate intervention, with an associated mortality of up to 50% [3] [4] [5] [6].
Its pathogenesis is not well established; however, it is common to have a direct wound due to instrumentation (which is continuously rising due to more common use of percutaneous and endoscopic hepatic interventions) or an indirect wound due to its association with acute cholecystitis or bile fugue [7].
Clinically, more than half of patients refer right upper quadrant abdominal pain which radiates to the back and almost a third present a classic triad of biliary colic, obstructive jaundice and haemobilia [8].
Past medical history as well as clinical suspicion of vascular wounds are an important part of the diagnosis, despite that, computed tomography angiography remains to be the gold standard in order to locate a vascular wound and assess its size and possible anatomical variants [9] [10].
The aim of this case report is to demonstrate that endovascular treatment with Amplatzer Vascular Plug 4 (AVP 4) systems in pseudoaneurysms, although not being the best treatment option, can be utilized as an alternative option in situations where there is no access to coils, nor microcoils for pseudoaneurysm exclusion.

Presentation and Investigations
54 years old patient with history of hypertension and morbid obesityis operated with a laparoscopic "Roux-en-Y" gastric bypass (LRYGB). Three days after original procedure starts complaining with dizziness, fatigue and light to moderate pain in right hypochondrium, showing anaemia with a 6 mg/dl haemoglobin concentration, haemobilia through T.-probe as well as clinical signs suggestive of hypovolemic shock such as tachycardia, tachypnea and weak arterial extremity pulses.
Due to prior surgical procedure, the clinical suspicion is oriented towards post-surgical complication, therefore, computed tomography angiography is conducted in order to examine the patient, demonstrating the presence of a hyperdense sacular image suggestive of hepatic pseudoaneurysm in the medial segment of the right hepatic artery (Figure 1).

Management
Coil embolization was considered, however due to not having available coils, conservative endovascular approach is decided: selective hepatic arteriography is conducted showing an opacification of the sacular pseudoaneurism ( Figure   2(a)), cannulation of the hepatic artery and placement of vascular plug system was performed using an Amplatzer Vascular Plug 4 ( Figure 2  The AVP4 model used was 9-AVP038-008 which has a vascular plug diameter of 8 mm and an unconstrained length of 13.5 mm. First, the loader was purged with sterile saline, the loader and delivery were removed from hoop dispenser, the delivery catheter was the the 0.038" Guidewire-Compatible Diagnostic Catheter 5F Dx Catheter. The catheter was advanced until the distal tip of the catheter was near the occlusion site (corroborated with arteriography) in the aneurysm nutrient artery. The guidewire was removed, followed by the insertion of the tapered tip, the rotating luer was grasped and pressed to the hub and then rotated clockwise. The delivery wire was advanced and placed and then, the delivery catheter was retracted to deploy the device at the occlusion site. Position of the device was verified using the marker bands. Delivery catheter and wire were removed. Case Reports in Clinical Medicine Outcome of procedure was positive and the patient progressively stabilized.
Patient was discharged five days later with a 11 mg/dl haemoglobin concentration and no symptoms nor clinical signs. Patient was followed up with subsequent tomography controls at three and eight months after procedure ( Figure   3(a), Figure 3(b)).

Management
Coil embolization was considered, however due to not having available coils, conservative endovascular approach is decided, and an angiography is conducted followed by the placement of Amplatzer Vascular Plug 4 system, therefore decreasing flow in the right hepatic artery ( Figure 5).
The AVP4 model used was 9-AVP038-007 which has a vascular plug diameter of 7 mm and an unconstrained length of 13.5 mm. First, the loader was purged with sterile saline; the loader and delivery were removed from hoop dispenser;  the delivery catheter was the 0.038" Guidewire-Compatible Diagnostic Catheter 5F Dx Catheter. The catheter was advanced until the distal tip of the catheter was near the occlusion site (corroborated with arteriography) in the right hepatic artery. The guidewire was removed, followed by the insertion of the tapered tip, the rotating luer was grasped and pressed to the hub and then rotated clockwise. The delivery wire was advanced and placed and then, the delivery catheter was retracted to deploy the device at the occlusion site. Position of the device was verified using the marker bands. Delivery catheter and wire were removed.
Outcome of procedure was positive and the patient progressively stabilized. Patient was discharged four days later with normal bilirubin concentration and no symptoms nor clinical signs. Patient was followed up with subsequent tomography controls at three and eight months after procedure (Figure 6(a), Figure  6(b)). Case Reports in Clinical Medicine

Discussion
Although pseudoaneurysms are a relatively rare entity, having a very high risk of rupture and being potentially lethal, makes them a really important possibility, they are a latent and probable early complication of abdominal trauma andseveral surgical procedures such as cholecystectomy, liver procedures, pancreatic surgeries or gastric bypasses [11] [12] [13]. Endovascular treatment however conservative is a widely performed procedure that has evolved to be the gold standard in the treatment of vascular occlusions and has demonstrated to be even safer than surgical treatments (such as ligation or revascularization) and A. Jiménez-Sastré et al.

Conclusion
Although the sacrifice of nutrient artery with AVP4 might not be the most appropriate treatment for pseudoaneurysms, due to urgency, Amplatzer Vascular Plug 4 may be a safe option, showing an adequate thrombosis after placement and having no recanalizations, hepatic lesions nor vascular wounds in posterior tomographic controls.

Patients Consent
Informed consent for use, analysis and publication of data for educational, divulgation and scientific aim was obtained assuring confidenciality of pertinent information and identification of both patients. First case patient and next to kin signed informed consent form. Second case patient's widow and next of kin signed informed consent form due to occupational fatality (oil industry).

Conflicts of Interest
The authors declare no conflicts of interest regarding the publication of this paper.