Background: Multi-phase Computed Tomography Angiography (mpCTA) is routinely performed prior to transcatheter aortic valve replacement (TAVR) to determine eligibility and enable pre-procedural planning. Incremental prognostic value may be realized from full-cycle, multi-phase reconstructions to assess the contractile health of cardiac chambers. This study aimed to assess the feasibility of 4D chamber modelling of the left ventricle (LV) to support 3D minimum principal strain (3DminPS) based predictions of clinical outcomes following TAVR.
Methods: Two hundred and five patients undergoing pre-TAVR mpCTA were studied. UNet-based 3D chamber segmentation was followed by mesh modelling and 3D feature tracking-based deformation to determine global 3DminPS for endocardial, epicardial and transmural layers. Independent associations of 3DminPS with the primary outcome of heart failure hospitalization or death were described.
Results: Of 205 patients, 196 (96%) had analyzable mpCTAs (median age 85 years; 55% male; STS-PROM score 3.10; and echocardiographic LV ejection fraction 60.0%). At a median of 25 months following TAVR, 55 patients (28%) experienced the primary outcome. Following adjustment for baseline variables, patients with an endocardial 3DminPS amplitude worse than -23.7% experienced a 2.7-fold higher risk of the outcome (aHR (95% CI) 2.7 (1.4-5.1), p=0.001), this high-risk cohort experiencing 1-year and 3-year event rates of 32% and 49%, respectively.
Conclusion: 4D chamber modelling of mpCTA using UNet-based segmentation and standardized mesh deformation is feasible and enables the delivery of 3D deformation markers with strong prognostic value for the prediction of outcomes following TAVR. Prospective validation in a multi-center setting is currently being executed.
Keywords: Computed Tomography; Left Ventricle; Prognosis; Strain; TAVR; Three Dimensional.
Copyright © 2024. Published by Elsevier Inc.