Author + information
- Sunil Kanwal,
- Isheeka Edwards,
- Mark Russo,
- Bruce Haik,
- Marc Cohen and
- Chunguang Chen
Background: Traditional aortic valve area (AVA) calculation by continuity equation (AVA-TTE) assumes a planar flow profile through a circular left ventricular outflow tract (LVOT). However, the flow profile is parabolic and LVOT is often elliptical. We hypothesized that a modified continuity equation using LVOT area traced on 3-D TEE and mean LVOT velocity integral (VTI) will provide a more accurate calculation of AVA compared to AVA-TTE.
Method: AVA was measured in 48 patients (Age: 78±11, Male: 60%) with aortic stenosis using AVA-TTE (LVOT diameter derived LVOT area by 2D TTE and LVOT VTI at a single point of LVOT), 3-D TEE planimetry (AVA–3D TEE), dynamic 4-D cardiac CT planimetry (AVA-CT) and a new modified continuity equation (AVA–modified). For the modified method, LVOT VTI was mapped at 3 points across LVOT (center of LVOT and both peripheral sides close to capture full spectrum of parabolic flow profile) and mean of the three LVOT VTIs was used.
Results: AVA-modified correlated better with AVA–3D TEE or AVA-CT than AVA-TTE did with AVA-3D TEE or AVA-CT (Fig. 1). Bland Altman average difference between AVA-TTE vs. AVA-3D TEE was 0.05±0.15cm2, between AVA-modified vs. AVA-3D TEE was -0.07±0.10cm2 and between AVA-modified vs. AVA-CT was -0.04±0.10cm2.
Conclusions: The new modified continuity method appears to be more accurate for calculation of the aortic valve area than traditional method with a better correlation with anatomic AVA by 3-D TEE or 4-D dynamic cardiac CT.
Poster Hall, Hall C
Friday, March 17, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Emerging Applications of Echocardiography
Abstract Category: 28. Non Invasive Imaging: Echo
Presentation Number: 1160-212
- 2017 American College of Cardiology Foundation