Background: 3D transesophageal echocardiography (TEE) may provide more accurate aortic annular and left ventricular outflow tract (LVOT) dimensions and geometries compared with 2D TEE. We assessed agreements between 2D and 3D TEE measurements with multislice computed tomography (MSCT) and changes in annular/LVOT areas and geometries after transcatheter aortic valve implantations (TAVI).
Methods and results: Two-dimensional circular (pixr(2)), 3D circular, and 3D planimetered annular and LVOT areas by TEE were compared with "gold standard" MSCT planimetered areas before TAVI. Mean MSCT planimetered annular area was 4.65+/-0.82 cm(2) before TAVI. Annular areas were underestimated by 2D TEE circular (3.89+/-0.74 cm(2), P<0.001), 3D TEE circular (4.06+/-0.79 cm(2), P<0.001), and 3D TEE planimetered annular areas (4.22+/-0.77 cm(2), P<0.001). Mean MSCT planimetered LVOT area was 4.61+/-1.20 cm(2) before TAVI. LVOT areas were underestimated by 2D TEE circular (3.41+/-0.89 cm(2), P<0.001), 3D TEE circular (3.89+/-0.94 cm(2), P<0.001), and 3D TEE planimetered LVOT areas (4.31+/-1.15 cm(2), P<0.001). Three-dimensional TEE planimetered annular and LVOT areas had the best agreement with respective MSCT planimetered areas. After TAVI, MSCT planimetered (4.65+/-0.82 versus 4.20+/-0.46 cm(2), P<0.001) and 3D TEE planimetered (4.22+/-0.77 versus 3.62+/-0.43 cm(2), P<0.001) annular areas decreased, whereas MSCT planimetered (4.61+/-1.20 versus 4.84+/-1.17 cm(2), P=0.002) and 3D TEE planimetered (4.31+/-1.15 versus 4.55+/-1.21 cm(2), P<0.001) LVOT areas increased. Aortic annulus and LVOT became less elliptical after TAVI.
Conclusions: Before TAVI, 2D and 3D TEE aortic annular/LVOT circular geometric assumption underestimated the respective MSCT planimetered areas. After TAVI, 3D TEE and MSCT planimetered annular areas decreased as it assumes the internal dimensions of the prosthetic valve. However, planimetered LVOT areas increased due to a more circular geometry.