Assessment of Coronary Artery Obstruction Risk During Transcatheter Aortic Valve Replacement Utilising 3D-Printing.

Background: Current imaging techniques may inadequately rule out coronary artery obstruction (CAO), a potentially fatal complication during transcatheter aortic valve replacement (TAVR). Advancements in three-dimensional (3D)-printing allow the development of models capable of replicating cardiac anatomy and predicting CAO. We sought to simulate TAVR utilising 3D-printed cardiac models to improve CAO risk assessment and procedural safety.

Methods: Thirteen (13) patients with aortic stenosis at high-risk of CAO during TAVR were selected for 3D-printed modelling. The relevant anatomy for TAVR was precisely reconstructed with Materialise Heart Print-Flex (Materialse, Leuven, Belgium) technology. An appropriately sized valve prosthesis was deployed in each 3D-model and coronary ostia assessed for obstruction.

Results: Model-derived results were compared to clinical outcomes in 13 cases. One high-risk case underwent TAVR resulting in left main obstruction and subsequent stenting. This outcome was accurately predicted by the 3D-model simulation. Two (2) high-risk TAVR cases were abandoned following transient CAO during balloon aortic valvuloplasty (BAV). The 3D-model simulations correlated with these findings, demonstrating CAO either by a calcium nodule or the native valve leaflet. In another two cases, BAV was uncertain, however the 3D-simulation demonstrated patency and successful TAVR was undertaken. In remaining cases, no obstruction was demonstrated in-vitro, and all underwent uncomplicated TAVR.

Conclusions: In this proof-of-concept study, 3D-model TAVR simulation correlates well to clinical outcomes. 3D-models of patients at high-risk of CAO may be utilised in pre-procedural planning to accurately predict this complication. As lower-risk surgical cohorts are considered for TAVR, 3D-models may minimise complications leading to safer patient outcomes.