Peripheral intravascular lithotripsy to facilitate transfemoral TAVR: a multicentric prospective registry
Authors: Nardi G , De Backer O , Ristalli F , Meucci F , Stolcova M , Wang X I , Sondergaard L , Palmerini T , Bruno A G , Al Jabri A G , Ielasi A G , Berti S , Saia F , Di Mario C 
Published: October 2021

Abstract

Background
The presence of severe calcific atherosclerotic disease at iliac artery level is a contraindication to transfemoral (TF) TAVI procedures, challenging TF delivery in 15–20% of cases. Many case reports described the efficacy of Intravascular lithotripsy (IVL) to facilitate TF access but only one prospective registry has been reported in literature and dates back 2018. For this reason a new multicenter prospective registry was ideated to confirm the role of IVL technology in facilitating TF TAVR.

Aims
The aims of this study were 1)to analyze the trend of TF TAVR compared to alternative approaches in the last 5 years and 2)to evaluate the prevalence of IVLassistedTAVR since it was introduced in this specific setting in 2018 3) to evaluate the success rate in terms of valve performance and procedural success of TF-TAVR system delivery after IVL lesion preparation.

Materials and methods
We prospectively collected data from all consecutive TAVRprocedures performed between Jan2016 andDec2020 at 4Italian and 1 Denmark centres. All patients underwent CT angiography of lower extremity before the procedure in order to assess the severity of aorto-iliac-femoral calcification and to select those patients who required specific lesion preparation to preserve TF access. For each target calcified lesion we measured length, diameter and %of stenosis, circumferential extension and minimal cross-sectional area. Angiographic IVL-related and access site complications (dissection, perforation, major bleeding) were examined.

Results
Between 2016 and 2020, a total of 3710 TAVR were performed, 3428 (92%) via TF route while the remaining 240 (8%) included alternative approaches mainly represented by subclavian and transapical access. IVL-assisted TAVR were 0 in 2016 and 2017, 13 (2%) in 2018 when the first IVL-assisted aortic valve implantation was performed and doubled in 2019, reaching a total of 112 in the whole 5-year period considered. The number of IVL-facilitated TAVR has been increased in the 5-year period, achieving 7% of the TF procedures while non-TF TAVR decreased considerably from 10% to 6%. Common and external iliac axis was the target lesion in the majority of cases (54%) followed by common iliac artery alone. lesion minimum diameter 4.7mm, with average stenosis of 50%. The maximum calcium angle was 332°. The majority of IVL was performed with a 7-mm catheter (78.6%). 1 balloon per lesion was employed. 1 perforation and 2 severe dissections occurred, that required stent placement. In 55% of cases the aortic regurgitation was absent or minimal.

Conclusions
TF approach remained the first choice for TAVR procedure in the majority of cases compared to non-TF thanks to the progressive increase of IVLassistedTAVR that allowed operators to preserve TF route. Peripheral IVL appeared feasible, safe and effective in patients with severe peripheral artery disease, with high success rate in terms of valve performance and low rate of complications.

Funding Acknowledgement
Type of funding sources: None.