Semi-automatic CT-angiography based evaluation of the aortic annulus in patients prior to TAVR: interchangeability with manual measurements

AbstractTo compare a semi-automatic software tool for the measurement of aortic annulus dimensions with manual measurements by expert readers and to analyze whether and to what extent interchangeability exists between semi-automatic and manual measurements. We retrospectively included 374 consecutive patients with high-grade aortic stenosis who had undergone CT-angiography of the heart prior to trans-catheter aortic valve replacement (TAVR). In independent analyses, two expert readers manually measured aortic annulus dimensions (long axis, short axis, circumference, area) as well as the distance of the coronary ostia from the annulus plane. A third independent reader performed annulus evaluation using a software tool for semi-automatic detection and measurement of the annulus plane. Intraclass correlation coefficients (ICC) and Bland –Altman analysis was used to compare both manual measurements as well as manual and semi-automatic measurements of annulus parameters. Using the respective measurements we simulated size selection for a Sapien XT transcatheter heart valve (THV). Interchangeability of methods was addressed by calcu lation of the estimated individual equivalence index γ. There was excellent agreement between both expert observers in manual measurements of the annulus with ICC’s in the range 0.89–0.94 for all anatomic parameters. Similar high agreements were observed between semi-automatic and manual measur ements, with ICC’s in the range of 0.89–0.95. TH...
Source: The International Journal of Cardiovascular Imaging - Category: Radiology Source Type: research