Because of its rigidity and non-steerability, the presence of a horizontal aortic root poses a major anatomical issue during transcatheter aortic valve replacement (TAVR) with Evolut self-expanding valve. Previous studies have elucidated the difficulties of coaxial implantation of the self-expanding valve in patients with horizontal aorta, often resulting in increased complications and a lower device success rate. To date, most patients with extremely horizontal aorta (aortic root angle ≥ 70°) have been excluded from major TAVR clinical trials. Therefore, available data on TAVR with Evolut in this challenging anatomy are limited, and standardized treatment strategies and clinical results remain unknown. Herein, we report a clinical case series of TAVR with Evolut in extremely horizontal aorta. Among seven patients (aged 80-92 years; STS score, 12.6% ± 7.9%) who underwent TAVR with Evolut system, aortic root angle ranged from 71° to 83° (mean, 75.1°± 4.5°). All patients achieved device success with dedicated strategies and were clinically stable at 3-month follow-up. None of the patients had more than mild paravalvular leakage (PVL) at any point during follow-up.Complications in three patients included complete atrioventricular block requiring a permanent pacemaker implantation, cerebral infarction because of atrial fibrillation 3 days after TAVR, and cardiac tamponade requiring pericardiocentesis. In this case series, Evolut self-expanding TAVR in extremely horizontal aorta was effective and feasible with a high device success rate. Based on anatomical features, some dedicated strategies majorly contribute to the success of this procedure. Large-scale multicenter studies are required to confirm our findings.
Keywords: Aortic stenosis; Horizontal aortic root; Self-expanding valve.