Performance of Dynamic Automated CT Annular Measurements Compared to Standard Manual Measurements for Transcatheter Aortic Valve Replacement Sizing.

PURPOSE: We sought to determine the performance of an automated computed tomography (CT) software that provides dynamic annular measurements of all available cardiac phases for transcatheter aortic valve replacement (TAVR) sizing as compared to the standard single manual measurement.
MATERIALS AND METHODS: In 60 TAVR patients (84±7 years, 60% male) who underwent pre-procedural CT scans, we measured the aortic annular diameters, perimeter, and area using (1) the dynamic automated CT measurements and (2) standard single manual measurement from the cardiac phase of maximum systolic opening by visual estimate.
RESULTS: The automated software was successful in providing annular measurements in 43/60 (72%) of cases, with the remainder requiring semi-automated contours. The maximum dynamic automated values were predominantly in systole (46/60[77%] for diameter, 44/60[73%] for perimeter, 48/60[80%] for area), and was a different phase from the standard manual phase in 46/60 (77%) cases. The maximum dynamic automated annular values were larger than the standard manual values measured (Δdiameter 0.35 mm, p=0.04; Δperimeter 1.71 mm, p<0.001; Δarea 15.6 mm2, p<0.001). When comparing standard manual to the same phase by automated measurements, while there was no difference in annular mean diameter (p=0.80), perimeter and area were larger with the automated measurements (Δperimeter 0.95 mm, p=0.002; Δarea 10.8 mm2, p=0.03). However, the maximum automated measurements were consistently larger than the same phase automated measurements (Δdiameter 0.13 mm, p<0.001; Δperimeter 0.42 mm, p<0.001; Δarea 4.4 mm2, p<0.001).
CONCLUSIONS: Automated maximum dynamic CT annular measurements provide larger values than standard manual and same phase automated measurements.