What measurements are required for planning of transcatheter aortic valve replacement (TAVR)?
Determination of eligibility for and planning of TAVR requires knowledge of both aortic root geometry and suitability of the access route for the valve. Measurements of the aortic annulus diameter, area, and perimeter are obtained from systolic phase ECG-gated acquisitions to determine which (if any) of the available prostheses will fit in the patient’s aortic root ( Figure 13-7 ). Coronary occlusion by the prosthesis is a rare but devastating complication of TAVR, and therefore the distance from the aortic annulus to the coronary artery ostia is measured to make sure that there is adequate clearance. The femoral artery is the preferred access route, and therefore femoral, iliac, and aortic minimal luminal diameters are measured; the presence of a large amount of calcified or noncalcified plaque in any of these vessels is also noted. If the transfemoral access route is not adequate, the prosthesis can be implanted through the subclavian artery, the ascending aorta, or the left ventricular apex. The use of CTA for TAVR planning has been demonstrated to reduce postprocedural complications such as perivalvular leak and aortic root rupture.