Cusp Overlap Technique: Should It Become the Standard Implantation Technique for Self-expanding Valves?

Abstract

Purpose of review: Accurate imaging of the aortic root during valve implantation is crucial for proper prosthesis positioning during TAVR. The purpose of this review was to determine if routine use of the cusp-overlap view should be adopted for self-expanding valves.

Recent findings: The use of the cusp-overlap view with the Evolut, Portico, ACURATE neo/neo2, and JenaValve systems is associated with lower post-procedural new permanent pacemaker implantation rates when compared with the standard 3-cusp view, presumably due to more precise valve implantation relative to the conduction system by the non-coronary cusp. By elongating the left ventricular outflow tract and accentuating the right-non commissure in the center of the fluoroscopic view, the cusp-overlap technique allows operators to more precisely control the prosthesis implant depth during self-expanding valve deployment. While the early experience with this approach in Evolut TAVR has been promising, the results of larger studies with longer follow-up across multiple self-expanding systems are warranted.

Keywords: Aortic stenosis; Commissural alignment; Cusp-overlap; Permanent pacemaker implantation; Self-expanding; Transcatheter aortic valve replacement.

Figure 1.. Deployment of the Evolut PRO+ Transcatheter Aortic Valve System Using the Cusp-Overlap Technique with Commissural Alignment: Step-by-Step.

A) A 3-cusp coplanar fluoroscopic view, followed by the RAO-CAU cusp-overlap view, is obtained. This can be achieved using the CT-derived fluoroscopic view or by placing a wire and pigtail respectively at the right- and left-coronary cusps and superimposing the two to get the cusp-overlap view. The Evolut PRO+ delivery system, once positioned across the aortic annulus, can be seen with the “Hat” marker facing center front (light blue circle) without parallax, thus simplifying the deployment process. At 80% deployment, if there is no parallax seen at the same cusp-overlap view, one does not need to rotate the C-arm to a more LAO projection to visualize the implant depth (solid white arrows) relative to the left cusp. B) As in this case, to avoid new conduction abnormalities, recapture and repositioning of the Evolut PRO+ valve higher relative to the non-coronary cusp (solid white arrows) may be required. Again, given that no parallax is seen at the inflow of the valve, there is no need to rotate the C-arm to a more LAO projection to visualize the implant depth relative to the left cusp. After release, the Evolut PRO+ valve is seen positioned at the optimal depth (solid white arrows). A cine image without contrast injection is obtained of the valve using both the 3-cusp and cusp-overlap views, thus confirming that the C-tab (orange circle) is at the inner curve of the ascending aorta. Using the fluoro-CT co-registration technique, good commissural alignment of the Evolut PRO+ valve with the native commissures can be visualized, potentially facilitating post-TAVR coronary reaccess. CAU = caudal, CRA = cranial, CT = computed tomography, L = left, LAO = left anterior oblique, L-R = left-right, LM = left main, N = non, N-L = non-left, N-R = non-right, R = right, RAO = right anterior oblique, RCA = right coronary artery.