Inter- and intra-observer repeatability of aortic annulus measurements on screening CT for transcatheter aortic valve replacement (TAVR): Implications for appropriate device sizing

•Multi-reader TAVR-CT evaluations have a lower measurement variability than single-reader measurements.•Multi-reader approaches reduce the rate of discrepant device size categorization.•Aortic annulus CT measurements for TAVR are highly reproducible. To investigate intra- and inter-observer repeatability of aortic annulus CT measurements for transcatheter aortic valve replacement (TAVR) by readers with different levels of experience and evaluate the impact of different multi-reader paradigms to improve prosthesis sizing. 82 TAVR screening CTAs were evaluated twice by three raters with six (R1 = radiologist), three (R2 = 3D-laboratory technician) or zero (R3 = medical student) years of experience. Results were translated into hypothetical TAVR size recommendations. Intra- and inter-observer repeatability between single readers and three different multi-reader paradigms ([A]: two readers, [B]: three readers, or [C]: two readers + an optional third reader) were evaluated. Intra-observer variability did not differ significantly (range: 50.1–67.8mm2). However, we found significant differences in mean inter-observer variance (p = 0.001). Multi-reader paradigms led to significantly increased precision (lower variability) for scenarios [B] and [C] (p = 0.03, p