Abstract 12384: Semi-automated versus Manual Aortic Annulus Analysis for Planning of Transcatheter Aortic Valve Replacement (TAVR/TAVI)
Background: Pre-procedural 3-D CT imaging plays a critical role for TAVR planning. However, manual reconstructions of the annular plane are complex. Semi-automated analysis software is incompletely validated.
Methods: In 109 TAVR patients (mean age 81years, 37% female) undergoing pre-procedural MDCT, semi-automated reconstruction of aortic annular plane and planimetry of the annulus was performed with a prototype of now available software (syngo.CT Cardiac Function-Valve Pilot, Siemens Healthcare, Erlangen, Germany). Measurements were compared to manual reconstruction. We compared disagreement in measurements between automated and manual methods, to disagreement among replicates from manual method using the individual equivalence index (IE). To assess the effect of these differences on treatment decisions, we classified annulus area measurements according to valve size (#23: 3.3-4.0, #26: 4.2-5.0, #29: 5.3-6.3cm2). We compared the frequency of agreement between two manual measurements and between semi-automated vs. manual measurement.
Results: Semi-automated analysis required major correction in 5 patients (4.6%). In the remaining 94.4%, only minor correction was performed. Mean manual annulus area was minimally (but significantly, p≤0.001) smaller than mean semi-automated measurement (Table). The adjusted difference between manual and semi-automated area was small (IE of 0.01), i.e. the difference between the two methods was only 0.1 mm2 larger than the expected difference between two manual measurements. Repeat manual or semi-automated measurements made by the same reader disagreed about valve size in 6 (5.5%) and 7 cases (6.4%), respectively. A semi-automated measurement and a manual measurement disagreed in 12.4% of the cases. The adjusted disagreement rate is 6.9% (i.e. 12.4-5.5).
Conclusions: Semi-automated aortic annulus analysis, with minor correction by the user, provides reliable results in the context of TAVR evaluation.
- © 2013 by American Heart Association, Inc.