Fig. 16.

Compromised delivery paths. A safe endovascular trajectory is needed for safe transportation of the THV to the aortic root. CT is in his respect an essential tool in order to avoid vascular complications and guide to the intervention through the safest possible passage. Potential complications may arise due to luminal narrowing or even chronic iliac artery occlusion with extensive collaterals (a) and pronounced vascular tortuosity and kinking (arrows in b). In this last case, there is an additional short dissection in the left external iliac artery (arrowhead) due to a previously performed conventional coronary angiography. For these patients, the preferred transfemoral access approach is therefore not possible, and other options have to be considered. Nevertheless, other access paths may also pose significant challenges, like bilateral subclavian artery narrowing and occlusion (arrows in c), and the presence of post-infarct thrombus and wall calcification in the left ventricular apex (asterisk in d), making a transapical approach with a balloon-expandable valve impossible. Therefore, vascular access examination must include all anatomic possible entry points for a full assessment of the different options