This retrospective analysis included consecutive patients who underwent transfemoral (TF) transcatheter aortic valve implantation (TAVI) at the Heart Center Lucerne between March 2009 and January 2025. From an initial population of 1,347 patients, those undergoing TAVI through nontransfemoral access (n = 61) and those who underwent magnetic resonance imaging instead of computed tomography before the procedure (n = 38) were excluded, resulting in a final study population of 1248 patients. All clinical endpoints were defined according to the Valve Academic Research Consortium-3 (VARC-3) criteria. The study protocol was approved by the local ethics committee (SwissTAVI registry, ClinicalTrials.gov ID NCT01368250) and all patients provided written informed consent.

The primary endpoint was the occurrence of CVA within 30 days following TAVI, including stroke and TIA as defined by the Valve Academic Research Consortium-3 (VARC-3) criteria. A CVA was defined as any sudden onset of neurological symptoms or signs, either affecting a specific area of the brain (focal) or the entire brain (global). A stroke was diagnosed when the focal or global neurological deficit persisted for 24 hours or longer, or when the neurological deficit resulted in death. A TIA was diagnosed when the focal or global neurological deficit resolved within 24 hours, and neuroimaging showed no evidence of new hemorrhage or infarct.

preprocedural computed tomography scans were analyzed for aortic arch morphology. Standard measurements included aortic valve dimensions (short axis, long axis, perimeter) and aortic arch measurements (base, height). For characterization of the aortic arch geometry, the angle between base and height of the aortic arch was measured. Additionally, a 7 cm standardized measurement line was placed from the top of the aortic arch, corresponding to the approximate housing length of self-expanding valves. Particular attention was given to the distribution and characteristics of soft plaques and calcification within this standardized measurement zone on the top of the aortic arch. Receiver operating characteristic (ROC) curve analysis identified 138° as the optimal angle threshold for predicting CVA at 30 days post-TAVI (AUC = 0.59, 95% CI: 0.53–0.64). While this AUC indicates only modest discriminative ability, it represents the optimal threshold in our dataset and warrants validation in larger cohorts. Based on this threshold, patients were classified as having either an acutely angled arch (gothic type, ≤138°) or a round arch (romanesque type, >138°).

Clinical follow-up was conducted at 30 days postprocedure and included physical examination, assessment of adverse events, and transthoracic echocardiography. Follow-up was limited to 30 days as this represents the standard timeframe for periprocedural complications as defined by VARC-3 criteria, and most embolic events related to device manipulation occur within this period.

Continuous variables are presented as mean ± standard deviation or median [interquartile range] as appropriate, and categorical variables as numbers and percentages. Comparisons between groups were performed using Student’s t-test or Mann-Whitney U test for continuous variables, and Chi-square or Fisher’s exact test for categorical variables. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cut-off value for the aortic arch angle in relation to CVA. The area under the curve (AUC) was calculated to assess the discriminative ability of different arch angle thresholds, with 138° emerging as the optimal cut-off point. Statistical analyses were performed using Stata 18.0 software (StataCorp LP) A p-value < 0.05 was considered statistically significant.