Prevention of Bilateral Coronary Obstruction During Valve-In-Valve TAVR With a Self-Expanding Valve

Abstract

Objective

We present a case of valve-in-valve transcatheter aortic valve replacement in an 85-year-old woman with severe bioprosthetic aortic valve stenosis at a high risk of left and right coronary artery obstruction. This risk was mitigated by a procedure combining both BASILICA and UNICORN (BABICORN [Bileaflet Alteration with BASILICA and Iatrogenic Cusp Obliteration Using Radiofrequency Needle]) for double leaflet modification.

Key steps

Electrosurgical traversal of the right leaflet and creating the electrosurgical loop using 2 guide catheters and an Astato wire within. Electrosurgical traversal of the left leaflet and ballooning the leaflet fenestration. Creating the flying V and lacerating the right leaflet. Serial ballooning and ultimately lacerating the left leaflet. Deployment of the Evolut valve.

Potential Pitfalls

Catheter entanglement, inadequate leaflet laceration, and stroke or systemic embolization.

Take-Home Message

The BABICORN procedure for double leaflet modification before valve-in-valve transcatheter aortic valve replacement with a self-expanding valve is technically feasible and preserves coronary flow in both native arteries.

Visual Summary

Visual Summary.

Step-by-Step Sequence

(A) Right leaflet traversed using an electrified Astato 40 wire within a Finecross microcatheter, (B) Astato wire snare in the LVOT, (C) Snare and Astato wire pulled into the MP guide catheter to create the electrosurgical loop, (D) left leaflet traversed using an electrified Astato 40 wire within a Finecross microcatheter, (E) Astato wire switched out for a Grand Slam wire and the leaflet fenestration dilated using a noncompliant coronary balloon, (F) Grand Slam wire exchanged for a Double Curved Lunderquist and an Armada balloon was positioned across the leaflet, (G) the “flying V” was created and advanced to the leaflet, (H) Astato wire electrified at 70W while injecting 5% dextrose and tension was applied to lacerate the leaflet, (I) both guide catheters taken out and a 5-F pigtail catheter taken up to the aortic root, (J) the Armada balloon was inflated, (K) Armada switched out for a 20-mm True balloon, with waist deformation upon inflation (∗), (L) full expansion of the True balloon, with disappearance of the waist indicating leaflet laceration, after which the valve was loaded on the same Lunderquist wire, (M) Evolut valve noted to be underexpanded after release, (N) valve postdilated with the same 20-mm True Balloon, and (O) final aortography showing excellent flow in both coronary arteries (black arrows). LVOT = left ventricular outflow tract; MP = multipurpose.

Equipment List.

Arterial and venous access •Ultrasound machine (Philips Healthcare, USA) •Micropuncture needle and wire •0.035-inch J wire •8F sheath × 2 – LFA & RFA •14F DrySeal sheath × 2 (Gore Medical, USA) – LFA & RFA •6F sheath × 2 – LFV & RRA •Proglide Prostyle × 2 (Abbott Vascular, USA) – LFA & RFA

Right leaflet BASILICA •6F Multipurpose catheter •0.035-inch V-18 wire (Boston Scientific, USA) •15mm Gooseneck Snare (Medtronic, USA) •7F JR4 guide catheter •4F angled Glide catheter (Terumo, Japan) •0.014-inch Astato 40 wire (Asahi, Japan) •Finecross microcatheter (Terumo, Japan) •5.0mm × 15mm non-compliant coronary balloon (Boston Scientific, USA) •Scalpel •Electrosurgery pencil •5% dextrose solution × 2

Left leaflet UNICORN •7F AL3 guide catheter •Astato 40 wire (Asahi, Japan) •Finecross microcatheter (Terumo, Japan) •0.014-inch Grand Slam wire (Asahi, Japan) •5.0mm × 12mm non-compliant coronary balloon (Boston Scientific, USA) •Navicross catheter (Asahi, Japan) •Double Curved Lunderquist wire (Cook Medical, USA) •6.0mm × 40 mm Armada balloon (Abbott, USA) •True Balloon 20 mm (BD Medical, USA)

TAVR •Pigtail catheter •Pacemaker •Alligator clips •Evolut FX+ delivery catheter system with inline sheath 14F (Medtronic Inc., USA) •Sentinel cerebral protection system (Boston Scientific, USA)

LFA = left femoral artery; LFV = left femoral vein; RFA = right femoral artery; RRA = right radial artery.

We present a case of valve-in-valve transcatheter aortic valve replacement (TAVR) in an 85-year-old woman with severe bioprosthetic aortic valve stenosis at a high risk of iatrogenic left and right coronary artery obstruction. This risk was mitigated by combining 2 electrosurgical techniques, BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction during TAVR) and UNICORN (undermining iatrogenic coronary obstruction with a radiofrequency needle), for double leaflet modification.^1,2

Take-Home Messages

• •The BABICORN procedure (Bileaflet Alteration with BASILICA and Iatrogenic Cusp Obliteration using Radiofrequency Needle) for double leaflet modification before valve-in-valve TAVR with a self-expanding valve is technically feasible and preserves coronary flow in both native arteries.
• •Potential benefits over “doppio” BASILICA include less technical complexity and shorter duration of exposure to acute aortic insufficiency in between and after leaflet lacerations.

Case Summary

An 85-year-old woman with a history of surgical aortic valve replacement with a 23-mm Edwards Magna Ease bioprosthetic valve presented with severe, symptomatic bioprosthetic aortic valve stenosis (peak velocity 4.4 m², mean gradient 49 mm Hg) and recurrent heart failure hospitalizations. Coronary angiography revealed nonobstructive coronary artery disease. Her Society of Thoracic Surgeons score was calculated at 9.2%. After a heart team evaluation, she was deemed a candidate for TAVR. Computed tomography angiography demonstrated heavily calcified bioprosthetic valve leaflets with an inner ring perimeter of 66 mm and area of 342 mm² (Figures 1A and 1B). We planned for TAVR with a 26-mm Evolut FX+ transcatheter heart valve (THV) (Medtronic) given better hemodynamics than the alternative of an undersized 20-mm or very oversized 23-mm SAPIEN 3 THV (Edwards Lifesciences). Bioprosthetic valve fracture was contemplated but deemed unadvisable secondary to a small left ventricular outflow tract (LVOT) diameter of 20.7 mm. Several anatomical features suggested a significant risk of iatrogenic obstruction of both the left and right coronary arteries after TAVR: short virtual THV-to-coronary distance (3.3 mm and 2.6 mm for the left main and right coronary arteries, respectively), low coronary heights <12 mm (10.7 mm and 10.1 mm), and small sinus of Valsalva diameters (25.6 mm and 24.7 mm) (Figures 1C to 1F). The virtual THV-to-sinotubular junction distance was 3.5 mm. The mechanisms of compromise were coronary ostial obstruction (by the displaced bioprosthetic leaflets), as well as sinus sequestration. We considered “doppio” BASILICA, with laceration of both the left and right leaflets (Figure 2). Upfront crossing of both leaflets followed by sequential leaflet laceration would have been the preferred strategy to allow timely valve delivery if hemodynamic instability ensued after the first laceration. However, we anticipated that manipulating several catheters, microcatheters, and electrosurgical loops would be quite challenging given the patient's small supra-annular anatomy. The only alternative double BASILICA strategy would be to cross and lacerate leaflets separately, which could be time-consuming, resulting in a longer vulnerable period of significant aortic insufficiency and possible hemodynamic compromise. The recently approved SHORTCUT device may have been a suitable option in this case, but it was not yet commercially available.³

Figure 1.

Case Plan

CTA showing (A) inner ring dimensions, (B) left VTC (note dense left leaflet calcification), (C) right VTC, (D) left coronary artery and SOV heights, (E) right coronary artery height, and (F) SOV dimensions. CTA = computed tomography angiography; SOV = sinus of Valsalva; VTC = virtual transcatheter valve-to-coronary.

Figure 2.

Comparison Between the 2 Approaches of Doppio BASILICA and BABICORN

Key procedural steps, pros and cons of each procedure. AI = aortic insufficiency; AV = aortic valve; LL = left leaflet; RL = right leaflet.

Early experiences with UNICORN for single leaflet modification before TAVR with balloon-expandable THVs have been promising.² Recently, technical modifications have been reported, allowing for TAVR using self-expanding THVs.^4,5 We believed that a double leaflet modification procedure combining BASILICA with UNICORN (or BABICORN – Bileaflet Alteration with BASILICA and Iatrogenic Cusp Obliteration Using Radiofrequency Needle) in this case would mitigate the risk of left and right coronary obstruction (Figure 2). Given the heavier calcium burden noted on the left coronary leaflet (Figure 1B), we planned for right leaflet BASILICA and left leaflet UNICORN before transfemoral TAVR.

Procedural Steps

We proceeded under general anesthesia and with transesophageal echocardiography (TEE) guidance. Two 8-F arterial sheaths were placed in the right femoral artery (RFA) and left femoral artery (LFA), respectively, using a modified Seldinger technique under ultrasound guidance. A Perclose ProStyle device was then deployed at each of the arteriotomies in the fashion of preclosure with knots tagged to the drape. A J wire was placed through each Perclose ProStyle device, and 14-F DrySeal sheaths were advanced through the RFA/LFA access sites. A 6-F sheath was then placed in the left femoral vein. A 6-F sheath was placed in the right radial artery. A Sentinel Cerebral Protection System was then placed with dual filters in the proximal innominate and left common carotid artery.

Predefined computed tomographic fluoroscopic angles and TEE imaging were used to guide leaflet traversal.

In our experience, traversal of the right coronary leaflet has been more challenging than traversal of the left leaflet. We therefore proceeded in a staged fashion, aiming to minimize interaction between traversal equipment, as well as exposure to aortic regurgitation between (and after) leaflet lacerations.

Traverse the right leaflet and create the electrosurgical loop

Through the LFA sheath, a 6-F MP guide catheter was placed over the J wire and the aortic valve crossed, with a V-18 wire placed to secure the ventricular position (Video 1). A 15-mm Goose Neck Snare was positioned in the LVOT below the right leaflet. Next, we used a telescoping system of catheters consisting of a 4-F angled Glide catheter inside a 7-F JR4 guide catheter to aim for the base of the right leaflet. We then advanced an Astato 40 wire to the leaflet within a Finecross microcatheter, traversed the leaflet using electrocautery, and then snared the Astato in the LVOT to form the electrosurgical loop. The V-18 wire was then removed.

Traverse the left leaflet

Through the RFA sheath, a 7-F AL3 guide catheter was positioned over the base of the left leaflet (Video 2). The leaflet was traversed using another Astato 40 wire within a Finecross microcatheter.

The Astato wire then was switched out for a Grand Slam wire, and the leaflet fenestration was dilated using a 5.0 mm × 12 mm noncompliant coronary balloon. Next, using a Navicross catheter, the Grand Slam wire was exchanged for a Double-Curved Lunderquist wire placed near the apex of left ventricle. The Navicross was then removed. A 6.0 mm × 40 mm Armada balloon was positioned across the leaflet.

Complete the right BASILICA

The Astato wire was externalized through the MP catheter, and the “flying V” was created by denuding a 1-mm segment on one side of the Astato wire just in front of the Finecross, then kinking this segment over the back of the scalpel blade (Video 3). This was then advanced to the leaflet. The Astato wire was then electrified at 70W while injecting 5% dextrose through both guide catheters, and tension was applied from both ends of the Astato to lacerate the leaflet. The resultant leaflet splay and aortic regurgitation were confirmed on TEE. Both guide catheters were then taken out, and a 5-F pigtail catheter was taken up to the aortic root through the LFA sheath.

Complete the left leaflet UNICORN

The Armada balloon was inflated twice to 12 atm (Video 4). This was then switched out for a 20-mm True balloon. This was inflated to lacerate the left leaflet while rapidly pacing using an Alligator clip system over the Lunderquist wire. Severe aortic regurgitation was noted on the TEE. The True Balloon was rapidly exchanged for the valve delivery system over the same Lunderquist wire.

Deploy EVOLUT valve

The surgical bioprosthetic valve was crossed using the Evolut (Video 5). The valve was then unsheathed slowly under direct fluoroscopic guidance using TEE as needed. Rapid pacing was performed. The valve was then unsheathed to the 2/3 position rapidly. Valve position was then assessed by aortography and TEE. The valve was then fully unsheathed and disengaged from the delivery catheter. The delivery system was then pulled into the descending aorta and removed after it was redocked with the nosecone. Because of underexpansion, we postdilated with the same 20-mm True balloon. Final aortography revealed excellent flow in the left and right coronary arteries. Hemodynamic assessment by TEE revealed a mean gradient of 7 mm Hg and no paravalvular regurgitation.

The Sentinel Cerebral Protection System was then removed. The RFA and LFA sheaths were removed, and the Perclose ProStyle knots were delivered to the arteriotomies with hemostasis confirmed by ultrasound.

Potential Pitfalls

Despite this technique using less catheters than a “doppio” BASILICA with upfront crossing of both leaflets, catheter entanglement in small aortic anatomies may still occur.

Heavy leaflet calcification can be a cause of failed BASILICA.⁶ In these situations, we believe that sequential ballooning of the leaflet with UNICORN effectively obliterates the leaflet; a phenomenon that has been described as “balloon-mediated leaflet annihilation.”⁵ We chose UNICORN for the more heavily calcified left leaflet for this reason.

Moreover, the risk of stroke and systemic embolization after UNICORN is unknown given the limited clinical experience with this novel procedure. We therefore opted to use the Sentinel cerebral protection system. Of note, both filters were free from any debris at the conclusion of the case.

Conclusions

The BABICORN procedure for double leaflet modification before valve-in-valve TAVR with a self-expanding valve is technically feasible and preserves coronary flow in both native arteries.

It offers several advantages over “doppio” BASILICA with separate leaflet crossing and laceration.

• 1.It is technically less complicated, requiring formation of only 1 electrosurgical loop.
• 2.Requires less catheters allowing for upfront crossing of both leaflets in small aortic anatomies, shortening the time between leaflet lacerations.
• 3.Shorter time to valve deployment because the valve can be deployed on the same UNICORN wire.
• 4.Potentially associated with a lower risk of catheter entanglement.

These factors simplify double leaflet modification and shorten the duration of exposure to acute aortic insufficiency (in between and after leaflet lacerations), potentially rendering BABICORN a better tolerated alternative that is easier to democratize among TAVR operators. To the best of our knowledge, this procedure has not been previously reported.

Funding Support and Author Disclosures

Dr Gada has served as a consultant to and received honoraria and research grants from Abbott Vascular, Boston Scientific Corporation, Edwards Lifesciences, Innovative Cardiovascular Solutions, Medtronic Inc, and PiCardia. Dr Kanmanthareddy has served as a consultant to and received honoraria and research grants from Medtronic Inc. Dr Mumtaz has served as a consultant to and received honoraria and research grants from Edwards Lifesciences, Japanese Organization for Medical Device Development, Medtronic Inc, and Z-Medical. Dr Ghoneem has reported that he has no relationships relevant to the contents of this paper to disclose.

Appendix

Video 1

Traversal of the Right Leaflet and Creation of the Electrosurgical Loop

Video 2

Traversal of the Left Leaflet

Video 3

Completion of the Right BASILICA

Video 4

Completion of the Left Leaflet UNICORN

Video 5

Deployment of the Evolut Valve