Impact of aortic angulation on outcomes in transcatheter aortic valve replacement with balloon-expandable and self-expanding valves: a systematic review and meta-analysis

High aortic angulation (AA) can pose significant challenges during TAVR. This meta-analysis determines the impact of a horizontal aorta on TAVR outcomes with balloon-expandable (BEV) and self-expanding valves (SEVs). A comprehensive search was conducted from inception to June 2024. Thirteen observational studies assessing the impact of aortic angulation in patients undergoing TAVR replacement were included. The pooled results indicated that short-term mortality was significantly lower in patients with a non-horizontal aorta (RR = 0.76; 95% CI 0.62-0.95, P = 0.01). Subgroup analysis displayed that BEVs had a lower short-term mortality with a horizontal aorta than SEVs. The incidence of stroke was not significantly affected by aortic angulation with either valve type. However, the overall risk of permanent pacemaker implantation was lower in patients with a non-horizontal aorta for both valve types. Paravalvular regurgitation was also reduced in the non-horizontal aorta group, with no difference between aortic angulations in patients with BEVs. In contrast, SEVs favored a non-horizontal aorta in reducing paravalvular leak (RR = 0.66; 95% CI 0.46-0.94, P = 0.02). Both BEVs and SEVs show better results in patients with lower aortic root angulation. The increased incidence of conduction abnormalities and PPI rates with both valve types in patients with horizontal aorta is a concern. BEVs could be potentially used preferentially to SEVs in patients with a horizontal aorta as there was no difference between horizontal and non-horizontal aorta groups regarding short-term mortality, moderate-to-severe paravalvular leak, and need for a second valve.