The research aimed to compare the differences in blood flow dynamics between two types of bioprosthetic valves used in transcatheter aortic valve replacement (TAVR) procedures - the balloon-expandable valve (BEV) and the self-expandable valve (SEV). The study involved 98 patients with severe aortic stenosis who underwent TAVR between May 2018 and November 2021.

The researchers used four-dimensional flow cardiovascular magnetic resonance (4D flow CMR) to examine the blood flow patterns, wall shear stress (WSS), and energy loss (EL) in the ascending aorta (AAo) before and after the TAVR procedure.

The study found that the self-expandable valve (SEV) group had significantly greater reductions in helical flow and flow eccentricity after TAVR compared to the balloon-expandable valve (BEV) group. The average WSS also decreased more in the SEV group. However, the reduction in systolic energy loss in the ascending aorta was similar in both groups after TAVR.

In conclusion, the study suggests that the type of valve implanted can affect blood flow dynamics. The SEV implantation resulted in a more significant decrease in helical flow, flow eccentricity, and average WSS in the ascending aorta compared to the BEV implantation. These insights could be beneficial in deciding which type of valve to use in TAVR procedures for patients with aortic stenosis. The researchers suggest that further large-scale studies are needed to confirm the implications of these hemodynamic changes on patient outcomes.

Yuki Takahashi, Kiwamu Kamiya, Toshiyuki Nagai, Satonori Tsuneta, Noriko Oyama-Manabe, Takeshi Hamaya, Sho Kazui, Yutaro Yasui, Kohei Saiin, Seiichiro Naito, Yoshifumi Mizuguchi, Sakae Takenaka, Atsushi Tada, Suguru Ishizaka, Yuta Kobayashi, Kazunori Omote, Takuma Sato, Yasushige Shingu, Kohsuke Kudo, Satoru Wakasa & Toshihisa Anzai , "Differences in blood flow dynamics between balloon- and self-expandable valves in patients with aortic stenosis undergoing transcatheter aortic valve replacement", Journal of Cardiovascular Magnetic Resonance, 25, Article number: 60 (2023) (2023) https://doi.org/10.1186/s12968-023-00970-9.