Computed tomography C-arm angulations for planning coronary cannulation after TAVI

To the Editor, Coronary re-access continues to be a challenge following transcatheter aortic valve implantation (TAVI). Commissural alignment of the prosthesis facilitates coronary re-access, especially in self-expanding prostheses.1 Additionally, for certain devices, different techniques for coronary cannulation might be necessary if the previously implanted prosthesis has commissural misalignment.2 By analyzing 3-cusp and left-to-right 2-cusp overlap (2-cusp) projections after TAVI, it is possible to estimate the degree of commissural alignment in prostheses with identifiable commissural posts on fluoroscopy.3,4 This study aimed to describe the optimal projections for left and right coronary artery (LCA, RCA) cannulation in patients with previous TAVI. We analyzed the pre-TAVI computed tomography scans of 105 consecutive patients referred to our center for TAVI implantation. Of these scans, 5 were excluded due to their poor quality or previous aortic valve replacement. The ideal projections for LCA and RCA catheterization were identified by using 3mensio software (Pie Medical Imaging, The Netherlands) and were defined as projections coplanar with the cross-sectional transverse plane of the aorta at the level of each coronary ostium and orthogonal to them, respectively. An en-face projection to the aortic annulus can be established intraprocedurally as a projection where the prosthesis is foreshortened, usually in a cranial (CRA)...