Non-surgical management of post-Ross left ventricular pseudoaneurysm assisted by virtual reality imaging

ABSTRACT

Infective endocarditis (IE) can cause extensive cardiac tissue destruction, often requiring surgical reconstruction with pericardial patches. The compromised integrity of necrotic tissue increases the risk of pseudoaneurysm formation. Redo surgical repair of pseudoaneurysms is associated with high morbidity; thus, catheter-based interventions may be preferable in select cases. Percutaneous transapical access provides a direct route to left ventricular pseudoaneurysms but demands thorough preprocedural planning and intra-procedural imaging. We report the successful transapical device closure of a large left ventricular pseudoaneurysm following a Ross procedure for aortic valve IE.

INTRODUCTION

Infective endocarditis (IE) in patients with a ventricular septal defect (VSD) and aortic valve prolapse can result in severe tissue destruction and aortic root abscess.[1,2,3] Surgical reconstruction of necrotic tissue may be complicated by left ventricular outflow tract (LVOT) pseudoaneurysm formation.[4,5] While surgery is the conventional treatment, repeat procedures carry significant morbidity. Transcatheter closure of cardiac pseudoaneurysms, after infection eradication, is an attractive alternative.[6,7,8,9,10,11] This report details the use of virtual reality imaging for preprocedural planning and intra-procedural guidance during transapical closure of a large, bilobed LVOT pseudoaneurysm with two orifices.

CASE REPORT

A 15-year-old boy with subpulmonic VSD and aortic valve prolapse developed aortic root abscess and severe aortic regurgitation due to IE. He underwent aortic root debridement and a Ross procedure, with LVOT repair using a pericardial patch. Four years postsurgery, routine echocardiography revealed a large pseudoaneurysm arising from the LVOT and enveloping the aortic root. An initial transcatheter closure attempt at another institution via retrograde femoral arterial access failed due to unstable sheath positioning.

At our center, transesophageal echocardiography (TEE) identified a 6 cm bilobed pseudoaneurysm from the LVOT with two orifices, located 1.5 cm below the autograft aortic valve hinge point. The neo-aortic valve function was preserved. Cardiac computed tomography (CT) and virtual reality reconstruction (VR) using Vmersive VR software from Poland facilitated procedural planning and virtual device placement [Figure 1]. Due to the inability to achieve stable retrograde access, a left ventricular apical approach was selected. The TEE images and multiplanar reformatted CT images showed two orifices of entry for this pseudoaneurysm located close to each other, with a larger caudal entry measuring around 8 mm directed toward the apex and a smaller cranial entry measuring around 4 mm towards the aortic valve. As the separation between the two was 2 mm and appeared very small, we presumed that a single self-centering device would stretch one of the orifices and achieve a closure. A volume-rendered VR image of the CT suggested an irregular shape of the two entry orifices that fused when reducing the gain settings [Figure 1].

Figure 1.

Multi-planar reconstruction in modified sagittal planes (a and b) and modified axial plane (c) on the preinterventional computed tomography shows a large bilobed pseudo aneurysm with partially calcified walls originating from the left ventricular outflow tract (LVOT) and extending around the aortic (Ao) root. There is a good distance between the aortic valve leaflets and the mouth of the pseudoaneurysm. Volume rendered images show the exterior surface of the bilobed aneurysm (d) and its mouth from the LVOT (e) and allow a virtual deployment of an occluder (f)

Under general anesthesia, the endotracheal tube was disconnected from the respirator to allow the collapse of the left lingular lobe and expose the left ventricular apex to the anterior left intercostal space. After echocardiographic confirmation, percutaneous apical puncture was performed, and a 7F Flexor sheath (Cook Medical, Bloomington, IN) was placed. The larger of the two orifices was accessed using a 5F Judkins Right catheter and a 0.035” hydrophilic Glidewire (Terumo corporation, Tokyo, Japan) to advance the Flexor sheath into the aneurysm. A 12-mm Amplatzer muscular VSD occluder (Abbott Medical, Plymouth, MN) was deployed, but residual flow persisted through a smaller cranial orifice on TEE [Figure 2]. This indicated that a single self-centering device did not stretch the larger orifice in the pericardial patch used to repair the LVOT during the surgery. The muscular VSD occluder was retrieved, and the smaller orifice was crossed under TEE guidance and closed with a 6–4 Amplatzer duct occluder II (Abbott Medical, Plymouth, MN). The larger orifice was then re-accessed and closed with the previously retrieved VSD device [Figure 3]. TEE confirmed complete closure, and angiography showed unobstructed LVOT flow. The apical puncture site was closed with a 6–4 Amplatzer duct occluder (Abbott Medical, Plymouth, MN).

Figure 2.

After percutaneous access through the left ventricular apex, the angiogram shows a large subaortic pseudoaneurysm (PsA) (a) that is cannulated through an end-hole catheter (b), confirmed by intra-procedural transesophageal echocardiogram (c). Angiogram after advancing the apical sheath into the aneurysm (d) allows deployment of an occluder device in its mouth (e). However, there are persistent color Doppler flows on transesophageal echocardiogram through a smaller cranial second orifice (f)

Figure 3.

After retrieving the previously deployed device, the smaller superior orifice (single arrow) of the pseudoaneurysm below the aortic valve (Ao) was crossed from the left ventricular outflow tract using an end-hole catheter (a). Color compare mode of transesophageal echocardiogram in long axial view (b) demonstrated superior and inferior orifices (two arrows). After deployment (c) of an Amplatzer duct occluder II device (ADOII) across the superior orifice (d), the larger inferior orifice (double arrow) was subsequently crossed (e), confirmed by echocardiogram (f), and closed (g) with the previously retrieved muscular ventricular septal occluder. Echocardiogram indicates complete closure (h)

The patient was extubated postprocedure and discharged on day 2 with aspirin therapy. Follow-up cardiac CT [Figure 4] demonstrated complete thrombosis of the pseudoaneurysm, and the patient remained asymptomatic after 1 year.

Figure 4.

Transapical sheath angiogram of the left ventricle (a) shows both occluders without any residual flows into the pseudoaneurysm (PsA), confirmed as shown by dense echo contrast within the PsA on long axial view of transesophageal echocardiogram (b). Axial section of computed tomographic angiogram at 1-month follow-up (c) shows complete thrombosis of the sac with partially calcified walls

DISCUSSION

IE can cause complex cardiac complications, including abscess, fistula, pseudoaneurysm, and valvular regurgitation, often necessitating urgent surgery.[4,9,10,11] The incidence of IE in VSD patients is 0.2–0.24 per 100 patient-years.[1,2] Aortic root abscess requires surgical intervention and full antibiotic therapy.[3] Extensive debridement minimizes residual infection and allows access to antibiotics and host defense. Aortic valve repair may be impossible if tissue destruction is severe, necessitating root replacement. The Ross procedure is preferred for its biological scaffold and minimal synthetic material.

Pseudoaneurysms are contained cardiac ruptures with a high risk of rupture or compression of adjacent structures.[4,7,8,9,10,11] Untreated LVOT pseudoaneurysms have a 45% rupture rate and 48% 1-year mortality; reoperation mortality is 20-30%.[5] Transcatheter closure is viable for patients with suitable anatomy and high surgical risk.[6,7,8,9,10,11] Identification of pseudoaneurysm on a routine follow-up echocardiogram in this case highlighted the importance of long-term post-operative monitoring. The pseudoaneurysm’s size and multiple orifices complicated transcatheter closure. As the VR images had suggested an irregular shape for the entry orifices, detection of a cranial residual flow following initial placement of the first device immediately indicated that the orifices could not be stretched to obliterate the second entry. This allowed us to immediately retrieve the first occluder and decide on the sequential deployment of two devices with a sandwich of the smaller low-profile occluder by the larger device. When a transapical access is performed, it is important to complete the procedure as swiftly as feasible. Any change in procedural plan, such as a change from a single occluder strategy to the creation of a sandwich between two occluders, would increase procedural time. As the VR reconstructions had suggested an irregular shape of the orifices earlier, the detection of residual flows above the caudally placed muscular VSD device immediately allowed us to switch to plan B, using a sandwich between two occluders.

Standard arterial access was unsuccessful due to sheath instability below the autograft valve, necessitating transapical access for direct LVOT entry and sequential closure under TEE guidance.[8] The complex nature of the pseudoaneurysm, with its shape and entry points, warranted meticulous planning based on the preprocedural images and VR reconstructions, as well as an intraprocedural TEE guidance.

The subannular region is the thinnest part of the left ventricle, predisposing it to pseudoaneurysm formation after trauma or infection.[8,9] Pseudoaneurysms within the context of perioperative infections are prone to progressive enlargement.[8,9,10,11] Repeat surgery carries high morbidity and recurrence risk due to weakened tissue failing to sustain surgical sutures.[11] Transcatheter closure is an appealing alternative, but care must be taken to avoid compromising valve leaflets and coronary arteries, and to confirm eradication of the infection. Transapical access offers a direct route compared to the circuitous retrograde arterial approach. Secure closure of the apical puncture is achieved with nitinol occluders and reversal of heparinization. Postprocedural surveillance should monitor for hemothorax and late apical aneurysms.

CONCLUSIONS

LVOT pseudoaneurysms after Ross procedure may be inaccessible via the retrograde transarterial route for transcatheter closure. Apical puncture is invaluable, especially with multiple orifices. Preprocedural CT and VR reconstructions enable precise intervention, while intra-procedural TEE ensures proper device placement and complete closure. Exclusion of active infection is mandatory before intervention.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.