A comparative study on iliofemoral artery calcification distribution in alternative TAVR approaches

Alternative access approaches are required for transcatheter aortic valve replacement (TAVR) cases wherein the transfemoral approach is restrictive with severe calcification. We aimed to examine the safety of the external iliac artery (EIA) as an alternative access site by evaluating the calcification distributions from the common iliac artery (CIA) to the common femoral arteries (CFA).

We retrospectively enrolled 402 patients who underwent TAVR. Using computed tomography, calcification was visually assessed based on the maximal circumferential involvement, length, and morphology, and its volumes were quantitatively measured using a minimum threshold of 600 Hounsfield units in 804 arteries.

The calcification volumes were 0.301 (interquartile range, 0.114–0.624) cc in the CIA, 0.0 (0.0–0.041) cc in the EIA, and 0.047 (0.002–0.158) cc in the CFA (p < 0.01). Maximum calcification of >50% of the arterial circumference was observed in only 7.3% of the EIA, compared to 35.2% and 10.8% of the CIA and CFA, respectively. Almost 55% of the EIA had no calcification, compared with only <5% and 22.7% of the CIA and CFA, respectively. In a subgroup analysis of patients on dialysis, the calcification volume was smallest in the EIA at 0.011 (0.0–0.127) cc (p < 0.01). In all, 33.3% of EIAs had no calcification, while 2.0% of CIAs and 19.6% of CFAs were calcification-free.

Calcification rarely presents qualitatively and quantitatively in the EIA, suggesting that it could be an option for TAVR when the transfemoral access is unsuitable.

We qualitatively and quantitatively evaluated the distribution of calcification in the iliofemoral arteries of patients who underwent TAVR. The calcification was more rarely present in the EIA than in the CIA or CFA.