Percutaneous Closure of Iatrogenic Ascending Aortic Pseudoaneurysms Following Surgical Aortic Repair.

We present a case series of 4 iatrogenic ascending aortic pseudoaneurysms that were all successfully repaired with a percutaneous approach. Pre-procedural imaging, device selection, and procedural techniques are described. With careful preparation and patient selection, catheter closure of iatrogenic ascending aortic pseudoaneurysms can be performed reliably and safely. (Level of Difficulty: Advanced.).

Pseudoaneurysms represent a collection of blood between the adventitia and media resulting from a disruption in the aortic wall. Iatrogenic ascending aortic pseudoaneurysms (IAAPs) are a rare but life-threatening complications of cardiac surgery. IAAPs occur when there is a disruption of the arterial wall with extravasation of blood, contained only by the periaortic connective tissue (1). They commonly arise from previous surgical incision sites. IAAPs are typically asymptomatic and are diagnosed on a follow-up computed tomography angiogram (CTA). Most IAAPs occur at the graft anastomoses and require repair, regardless of size or location, given the risk of catastrophic rupture. The timing and modality of repair of these defects remain challenging. Open surgical repair is considered standard of care but can be difficult and has substantial morbidity and mortality (2). Thoracic endovascular aortic repair (TEVAR) can be used successfully but has limitations, and it is contraindicated when a risk of occlusion of head vessels or coronary arteries is present (3). When pre-procedural imaging demonstrates appropriate anatomy, direct transcatheter closure offers a minimally invasive approach that avoids the need for proximal and distal landing zones (4). We report successful percutaneous closure of 3 IAAPs in the last 18 months with different techniques.

Learning Objectives

To understand the role of imaging for location and sizing of the defect and to detect adjacent structures.

To review the equipment options and techniques, including use of catheters, sheaths, closure devices, and coils.

A 74-year-old man underwent ascending aortic graft (AAG) placement for an ascending aortic aneurysm including aortic valve replacement. Follow-up CTA 2 months post-surgery revealed a 94 × 79 × 56 mm IAAP along the proximal anastomosis of the AAG (Figure 1A). Surgical risk was considered prohibitive. The IAAP had a focal neck and was believed to be amenable to percutaneous closure despite the large size of the IAAP (Figure 1B). The procedure was performed with transesophageal echocardiography (TEE) guidance (Figure 1C). Through femoral artery access, an 8-F multipurpose (MP, Cordis, Santa Clara, California) guide and a 6-F Judkins Right 4 (JR 4, Cordis) catheter were used in a telescoping fashion with a floppy-tipped glide wire (Terumo, Shibuya, Japan) to engage the IAAP selectively. The glide wire and JR 4 catheter were exchanged for an Amplatz extra stiff wire (AES, Cook Medical, Bloomington, Indiana) and a Balance Middle Weight wire (BMW, Abbott, Abbott Park, Illinois) wire as a buddy wire. The MP guide was then exchanged for an 8-F 90-cm Shuttle sheath (Cook Medical), which was advanced into the IAAP. Under TEE and fluoroscopic guidance, an 11-mm Amplatzer septal occluder (ASO, Abbott) was deployed through the neck of the IAAP. The IAAP began to clot off immediately (Figure 1D, Video 1). An aortogram (Figure 1E), and follow-up CTA (Figure 1F) confirmed complete occlusion of the neck with no residual filling of the IAAP and stable device position.

Figure 1

Case 1

(A and B) Oblique computed tomography angiogram images showing the iatrogenic ascending aortic pseudoaneurysm (arrows) along the proximal anastomoses of the ascending aortic graft. The measurement shows the neck size of the iatrogenic ascending aortic pseudoaneurysm. (C) Intraprocedural transesophageal echocardiography images showing the aortic root in a short axis. Multiple short arrows are pointing at the iatrogenic ascending aortic pseudoaneurysm. The thin white arrow is pointing at the Doppler signal of the shunt through the neck of the iatrogenic ascending aortic pseudoaneurysm. (D) Intraprocedural color-compare transesophageal echocardiography images showing the aortic root in a short axis after device deployment. The black arrow is pointing at the device. A clot is starting to form, filling the iatrogenic ascending aortic pseudoaneurysm. (E) Cine imaging with contrast injection in the aortic root confirms complete occlusion of the neck (arrow) with no residual filling of the iatrogenic ascending aortic pseudoaneurysm. (F) Oblique computed tomography angiogram postprocedural shows stable device position (white arrow) with no residual flow.

A 56-year-old man presented to the emergency department with chest pain and voice hoarseness after undergoing a total aortic arch replacement with coronary artery bypass grafting (including a saphenous vein graft [SVG]) for an aortic arch aneurysm 2 months before presentation. CTA revealed multiple IAAPs anterior and posterior to the AAG. The patient underwent emergency re-do sternotomy; however, because of extensive inflammatory adhesions, the procedure was converted intraoperatively to endovascular repair, and the distal IAAP was treated with TEVAR. Follow-up CTA 4 weeks later demonstrated a persistent proximal IAAP at the origin of the SVG around the proximal portion of the graft, measuring × 30 mm (Figure 2A) with a neck size of 10.4 mm. Given that the SVG communicated with the IAAP (Figure 2B, Video 2), the SVG would need to be sacrificed to avoid backfill and continuous pressurization of the IAAP through retrograde flow from the SVG. In anticipation of closure, the native circulation supplied by the SVG was stented. An aortogram confirmed the presence of the IAAP at the origin of the SVG (Figure 2C). Intravascular ultrasound measured the size of the SVG to be 5.8 mm. Over a wire, a 5-F MP catheter was advanced through a 7-F Amplatz Right-1 (AR-1, Cordis) guide into the SVG. A Lantern microcatheter (Penumbra, Inc., Alameda, California) was used to coil the proximal SVG with a combination of soft and standard Ruby coils (Penumbra Inc.) (Figures 2D to 2F). A coronary angiogram confirmed proper embolization of the SVG. Injection of the native coronary arteries showed no significant backfilling into the SVG (Video 3). The IAAP was then selected with the AR-1 guide, the MP catheter, and a BMW wire, which was exchanged for an AES wire. However, the steep angle between the IAAP neck and the ascending aorta and the position of the leak along the inner curve of the graft turned out to be highly unfavorable (Figure 2D). Multiple unsuccessful attempts were made, including with a 90-cm Shuttle sheath and an 8.5-F 90-cm Aptus TourGuide (Medtronic, Minneapolis, Minnesota) over a Lunderquist wire (Cook Medical). Coil embolization of the IAAP was believed to the best alternate approach. The MP catheter and BMW wire were advanced into the IAAP through the AR-1 guide. The wire was removed, and a Lantern microcatheter was advanced; coil embolization of the IAAP was performed by first using large standard Ruby coils (Figure 2E), followed by multiple small soft Ruby coils and packing coils for a total of 34 coils (Penumbra, Inc.) until the entire IAAP was filled (Figure 2F). Post-operative CTA confirmed no residual flow into the IAAP.

Figure 2

Case 2

(A and B) Oblique computed tomography angiogram images showing an iatrogenic ascending aortic pseudoaneurysm (arrow in A) at the proximal anastomosis of the arch replacement graft. The arrow in B points at the saphenous vein graft origin. (C) An aortogram confirms the origin of the saphenous vein graft arising adjacent the iatrogenic ascending aortic pseudoaneurysm (white arrow). (D) Contrast injection into the iatrogenic ascending aortic pseudoaneurysm confirms successful coil embolization of the saphenous vein graft (thin arrow). (E and F) The white arrows point at the iatrogenic ascending aortic pseudoaneurysm filled with Ruby coils.

A 56-year-old woman underwent repair of an acute type A aortic dissection with an AAG. Follow-up CTA at 5 months showed active extravasation at the proximal anastomosis of the graft and the aortic root into a mediastinal IAAP measuring 118 × 83 × 77 mm (Figures 3A and 3B). The IAAP was located adjacent to sternum, thus rendering a redo sternotomy without entering the IAAP very difficult. The focal neck of the IAAP was deemed amenable to percutaneous closure with an ASO device. The procedure was done with TEE guidance given the complex anatomy. Because of the proximity of the right coronary artery (RCA) to the neck, a JR 4 guide and a BMW wire were used to mark the RCA ostium during the procedure to avoid inadvertent obstruction (Figure 3B). TEE color Doppler imaging showed a maximal width of jet of 9 mm, and therefore an 11-mm ASO was chosen (Figure 3C). The radius of the ASO aortic-sided disk (10.5 mm) was less than the 12 mm from the IAAP neck to the RCA ostium. An 8-F MP guide was used with a 6-F JR 4 catheter and an angled glide wire in a telescopic fashion to gain access to the IAAP. Once the JR 4 catheter was engaged in the IAAP, the glide wire was exchanged to a 260-cm J wire for better support, over which the MP guide was carefully advanced into the IAAP. The J wire was exchanged to an AES wire, over which an 8-F 90-cm Shuttle sheath was slowly tracked into the IAAP (Figure 3D). A BMW wire was advanced over the sheath into the IAAP as buddy wire. TEE proved very helpful to ensure proper placement of the 11-mm ASO given the steep angles necessary for a side-on view of the ASO in the aortogram (Figure 3E). The initially pressurized IAAP with bidirectional flow clotted off immediately (Video 4). Follow-up CTA demonstrated stable device position, no residual jet, and a fully thrombosed IAAP (Figure 3F).

Figure 3

Case 3

(A and B) Oblique computed tomography angiogram images showing an iatrogenic ascending aortic pseudoaneurysm (multiple small arrows) along the proximal anastomosis of the aortic graft. The iatrogenic ascending aortic pseudoaneurysm shows active extravasation (long arrow in A) and is partially clotted. The measurement in B shows the right coronary artery ostium to be 12 mm proximal to the iatrogenic ascending aortic pseudoaneurysm neck. (C) Intraprocedural transesophageal echocardiography images showing the aortic root in a long axis. The bidirectional color jet into the iatrogenic ascending aortic pseudoaneurysm (multiple short arrows) measures a neck size of 9 mm. (D) Contrast injection through the Shuttle sheath (Cook Medical, Bloomington, Indiana) into the iatrogenic ascending aortic pseudoaneurysm (multiple arrows). (E) Intraprocedural transesophageal echocardiography showing the aortic root in a short axis after device deployment (black arrow). A clot is starting to form, filling the iatrogenic ascending aortic pseudoaneurysm s. (F) Oblique computed tomography angiogram images postprocedural demonstrate stable device position and fully thrombosed iatrogenic ascending aortic pseudoaneurysm with no residual jet visible (arrows).

A 57-year-old male had undergone elective repair of an AAA with an AAG 4 years prior. On follow-up CTA, he was found to have an IAAP measuring 34 × 23 × 38 mm at the distal anastomosis of the AAG (Figure 4A and 4B). The neck of the IAAP was measured to be 10 mm and therefore deemed suitable for percutaneous repair (Figure 4B). The IAAP was selectively engaged with a 6-F JR 4 guide (Figure 4C), over which a BMW wire was advanced into the pseudoaneurysm, followed by a straight Glidecath (Terumo, Shibuya, Japan). The BMW was then exchanged for an Amplatzer extra stiff wire, and both JR 4 and Glidecath removed. An attempt to advance an 8-F Torqvue delivery system into the IAAP failed. Instead, an 8-F 90 cm Shuttle sheath was successfully tracked into the IAAP (Figure 4D). After removal of the extra stiff wire, an 11 mm ASO was advanced and proper positioning was confirmed with multiple fluoroscopic projections. Aortogram confirmed successful occlusion of the IAAP with no residual flow after deployment (Figure 4E). A post-operative CTA showed only trivial filling of the IAAP anterior to the distal graft (Figure 4F), which has been managed conservatively.

Figure 4

Case 4

(A and B) Volume rendered and oblique computed tomography angiogram (CTA) images showing a 34 × 23 × 38 mm iatrogenic ascending aortic pseudoaneurysm (IAAP, arrows) at the distal anastomosis of the ascending aortic graft with a neck measuring 10.5 mm. (C) Intraprocedurally the anatomy was confirmed with contrast injection into the IAAP (white thin arrow). (D) The challenging anatomy required a Shuttle sheath for delivery of the device. (E and F) Aortogram and CTA post-procedural demonstrate successful closure of the IAAP with an Amplatzer atrial septal occluder device (white thin arrows).

Discussion

When redo open surgery or TEVAR is inadvisable, percutaneous transcatheter closure of IAAP can be performed safely, with good results. Patients have to be carefully selected and screened for connective tissue diseases and arteritis in case of clinical signs or young age (<45 years). From a technical standpoint, the origin of the IAAP has to be precisely located, and its relationship with adjacent structures, such as the sternum, bypass grafts, or coronary arteries, must be understood. For perioperative planning, 3-dimensional CTA reconstructions are the gold standard.

Whenever possible, we use an ASO device for closure because this represents the most economical and straightforward approach for percutaneous IAAP closure. With this strategy, the diameter of the neck, not the overall size of IAAP, is the critical factor determining suitability for closure. Use of intraprocedural TEE can be very helpful to confirm neck size and closure of the neck. ASOs are chosen with a waist 1 to 2 mm larger than the neck size. The IAAP should first be accessed with a soft wire, over which a 125-cm catheter and a guide in a telescopic fashion can be safely advanced and exchanged for stiffer support wires. Use of a buddy wire (coronary wire) in case of loss of position is recommended. We recommend using the 8-F 90-cm Shuttle sheath in combination with a hemostatic rotating valve, instead of the stiff TorqVue delivery system (Abbott), given better trackability. Because of the steep angles between the aorta and the neck, advancement of the catheter, the guide, and finally the delivery sheath has to be performed slowly, preferably by 2 operators.

Flexibility in approach is helpful. As demonstrated in our second case, IAAPs that are located at the inner curve of the ascending aorta with steep angulations into the entry site can render ASO placement impossible. In these situations, coil embolization of the IAAP can be performed. A focal neck is still an important consideration to avoid escape of the coils out of the IAAP, and starting with largest coils possible to outline the defect and then packing the IAAP with smaller coils is recommended.

In summary, patients with IAAPs present an unusual but challenging subset requiring a range of approaches for management, in addition to open repair and TEVAR. As demonstrated here, catheter-based closure or coil embolization can be used with good results in certain high-risk patients with appropriate anatomy.

Funding Support and Author Disclosures

Dr. Stehli is supported by a Monash University scholarship. Dr. Panneton is a consultant for and in the Speakers Bureau of Medtronic, Terumo Aortic, WL Gore, and Penumbra. Dr. Mahoney is a consultant and proctor for Medtronic, Abbott, and Edwards. Dr. Alie-Cusson has reported that she has no relationships relevant to the contents of this paper to disclose. This project did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors.