Author + information
- Gilbert H.L. Tang, MD, MSc, MBA∗ (, )
- Syed Zaid, MD,
- Iassen Michev, MD,
- Hasan Ahmad, MD,
- Ryan Kaple, MD,
- Cenap Undemir, MD,
- Martin Cohen, MD and
- Steven L. Lansman, MD, PhD
- ↵∗Structural Heart Program, Mount Sinai Health System, Icahn School of Medicine at Mount Sinai, 1190 Fifth Avenue, GP2W, Box 1028, New York, New York 10029
Accurate device implantation in transcatheter aortic valve replacement (TAVR) depends on: 1) obtaining a 3-cusp coplanar projection; and 2) centering delivery catheter across the valve. Unlike balloon-expandable valves, which require a coplanar projection with 3 cusps (yellow dot = non [N], green = right [R], red = left [L]) (1) (Figure 1A), additional steps are taken when implanting a self-expanding valve, for example, CoreValve/Evolut R (Medtronic, Minneapolis, Minnesota). First, parallax of the delivery catheter (yellow arrow) should be eliminated, requiring a more caudal/cranial and not coplanar view (Figure 1B). Second, the delivery catheter is naturally positioned toward the outer curvature of the aortic root (red arrow) (Figure 1B). Third, annular contact occurs from the non-coronary cusp (NCC) to the left coronary cusp (LCC) (Figures 1C and 1D), with the dotted blue arrow indicating direction and approximate distance for the valve frame to anchor (Figure 1D).
A coplanar projection by overlapping the right coronary cusp (RCC) and LCC (cusp-overlap view) offers several potential advantages in CoreValve/Evolut R deployment (Figures 1E to 1T):
1. Elimination of parallax of the delivery catheter,
2. Delivery catheter more centered across aortic valve,
3. Deployment in true coplanar view,
4. Shorter visual distance for CoreValve/Evolut R to engage the NCC and LCC, and
5. En-face view of NCC enables higher valve implantation without device “pop-out” upon release, especially in a large annulus with minimal oversizing.
This concept is illustrated in a sample multidetector computed tomography (MDCT) analysis using 3Mensio Valves software (Pie Medical Imaging, Maastricht, the Netherlands). Standard 3-cusp view of left anterior oblique (LAO) 8°, caudal 3° is viewed by an operator at the position of the solid white arrow, projecting more along the annular long axis (Figure 1E). Natural positioning of the CoreValve delivery catheter (blue circle) between the NCC (yellow dot) and the RCC (green dot) (Figures 1F and 1G) requires the valve frame to engage the LCC (red dot) in the direction of the solid blue arrow. However, under fluoroscopy, the perceived valve frame flowering would actually be in the direction and distance of the dotted blue arrow (Figures 1F and 1G), depicted in Figure 1H. A coplanar projection of the same patient using the cusp-overlap view, in this case, right anterior oblique (RAO) 13°, caudal 30°, overlaps the RCC and LCC, and displays the annulus more toward the short axis (Figure 1I). The delivery catheter appears more centered (Figure 1J), and perceived distance (dotted blue arrow) of the valve frame flowering from the NCC to the LCC is reduced (Figures 1J and 1K), as depicted in Figure 1L.
Figure 1M shows the initial MDCT-derived 3-cusp view confirmed by 2 pigtail catheters without intravenous contrast, followed by placing them at the RCC and LCC, respectively, to achieve the cusp-overlap view (Figure 1N). Initial device positioning at RAO 13°, caudal 30° shows no parallax of a more centered delivery catheter (yellow arrow) (Figure 1O). The NCC nadir is better visualized (Figure 1P), allowing a higher valve deployment with a lower risk of “pop-out.” Annular contact from the NCC to the LCC occurs over a shorter distance (dotted blue arrow) during valve flowering and deployment (Figures 1Q and 1R). Completion aortograms at projections coaxial to the CoreValve show that inflow (dotted white arrows) and waist diameters appear smaller in the Cusp-Overlap (Figure 1S) than in the coplanar view (Figure 1T), consistent with perceived differences due to axis orientation of the annulus on MDCT.
A dedicated software or MDCT is not necessary to identify the cusp-overlap view, because it can be accomplished fluoroscopically by placing a pigtail catheter in the RCC and either an angled pigtail, 0.035-inch J wire, or 0.018-inch pre-shaped soft nitinol wire in the LCC. Rotating the C-arm to superimpose both catheters (or wire) enables overlapping of the RCC and the LCC, generating the cusp-overlap view (Figure 1N). Our technique also does not require a third arterial puncture. The pigtail or guidewire is removed from the valve access site after the angle has been determined. Although the 2-pigtail technique has been used in TAVR with pure aortic insufficiency, here we report using a similar technique to determine the novel cusp-overlap view to facilitate TAVR with the CoreValve.
In patients with challenging body habitus, such as obesity, an RAO, caudal view may reduce fluoroscopic image quality, and certain extreme RAO, caudal angles may not be possible to create the cusp-overlap view. In those instances, we perform CoreValve TAVR using a 3-cusp view or overlapping the NCC and the RCC in an LAO, cranial view. When overlapping 2 cusps, it is essential to place the 2 pigtails or a pigtail and a wire in the overlapping cusps, respectively, to ensure they are coplanar. We believe this rule may simplify implantation of certain self-expanding valves, such as the Evolut R CoreValve and Portico (Abbott Structural Heart, Santa Clara, California).
Please note: This study was previously presented at the following annual meetings: PCR London Valves in 2015, TCT in 2016, and ACC in 2017. Dr. Tang has been a physician proctor for Edwards Lifesciences and Medtronic. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2018 American College of Cardiology Foundation