Access Options for Transcatheter Aortic Valve Replacement

Abstract

Transcatheter aortic valve replacement (TAVR) was introduced in 2002 and has become integral in the management of aortic stenosis. As an alternative to surgical aortic valve replacement, it relies heavily on safe access to the aortic annulus for implantation of a valve prosthesis. Throughout its development and in current practice, the transfemoral (TF) arterial route for retrograde valve delivery has been the primary approach. However, this route is not appropriate for all patients, which has led to the development of multiple alternate access options. This review discusses the development of access for TAVR, followed by a thorough discussion of TF access. The commercially available products, preprocedural planning, closure techniques, and procedural complications are all discussed. We also describe the various alternate access routes with particular emphasis on the most recently developed route, transcaval access (TCv), with focus on procedural indications, technical considerations, and comparative outcomes. As TAVR technology, indications, and availability all expand, the knowledge and implementation of safe access are of utmost importance.

Keywords: arterial access; transaortic; transapical; transaxillary; transcarotid; transcatheter aortic valve replacement; transcaval; transfemoral.

Figure 1

TAVR Access Sites with Site-specific Considerations. Adapted from [11].

Figure 2

Chronologic Development and Frequency of TAVR Access Sites. Adapted from [3].

Figure 3

Transcaval Access (A) Traversal assembly at the site predetermined by computed tomography angle, and aortogram via the pigtail catheter. (B) Snare is positioned across the traversal system. (C) Position of the snare across the traversal system is confirmed in the orthogonal en face projection. (D) 0.014-inch guidewire is traversed across the vena cava and aorta into the snare with electrosurgery. (E) The aortic guidewire is ensnared while feeding forward to avoid outward traction on the aortic catheter. (F) The aortic guide is advanced, leading with a looped guidewire. (G) 0.014-inch microcatheter (arrow) is advanced over the 0.014-inch guidewire. (H) A 0.014-inch microcatheter (arrow) creates a 0.035-inch caval-aortic rail to deliver a 0.035-inch microcatheter. (I) A stiff 0.035-inch guidewire is delivered up to the aortic arch through the 0.035-inch microcatheter. (J) The transcatheter aortic valve replacement introducer sheath advances into the aorta.

Figure 4

Transcaval Closure (A) A 0.014-inch “buddy guidewire” (arrow) across the aortocaval tract allows recrossing in case of inadvertent device pull-through. (B) Partially exposed (“bulbed”) nitinol occluder (arrow). (C) “bulbed” occluder turns sideways when withdrawn while deflecting the guiding sheath. (D) Aortogram before releasing the nitinol occlude for the confirmation of the position. (E) 0.014-inch “buddy guidewire” (arrow) is withdrawn back into the vena cava after the device position is confirmed and before releasing the device. (F) The nitinol occluder is released. (G) Completion aortogram shows the “funnel”-shaped aortocaval fistula, which usually resolves within a few days to weeks. (H) Completion cine image of the occluder device.