Role of three-dimensional transesophageal echocardiography in transcatheter aortic valve implantation of bicuspid aortic valve stenosis: A controlled study and comparison with tricuspid aortic valve stenosis

Aims: This study aims to investigate the application of three-dimensional transesophageal echocardiography in aortic valve stenosis for the assessment of aortic valve ring size, to monitor the procedure of transcatheter aortic valve implantation (TAVI), and perform postoperative follow-up. Methods: Eighteen patients with bicuspid valve malformation and severe aortic stenosis bicuspid aortic valve (Group BAV-AS) and 23 patients with a tricuspid valve and severe aortic stenosis trileaflet aortic valve (Group TAV-AS) were enrolled in this study. Preoperative routine transthoracic echocardiographic (TTE) examination and two- and three-dimensional transesophageal echocardiography (2D and 3DTEE) were performed, followed by perioperative 2D and 3D TEE monitoring and postoperative routine TTE at 6-month follow-up. Results: Both BAV-AS and TAV-AS patient groups were successfully implanted with bioprosthetic valves under 3DTEE guidance. Parameters at 6-month postoperatively, including prosthetic valve orifice area, mean aortic transvalvular pressure gradient, and left ventricular ejection fraction, showed significant improvement compared with baseline measures (P < 0.0001) in both the groups. No differences were observed between the groups. The maximum diameter of the aortic annulus and eccentricity index were larger in the BAV-AS group than in the TAV-AS group, whereas the minimum diameter of the aortic annulus was larger in the latter (both P < 0.0001) after TAVI. Moreover, the values of maximum and minimum diameters on 3DTEE were strongly correlated with those on multidetector computed tomography. Conclusions: TEE is capable of clearly displaying the morphology of aortic valves and valve rings and precisely quantifying the size of the aortic annulus, thereby playing an essential role during preoperative and perioperative periods. The postoperative shape of the prosthetic valve ring was more oval (larger than normal eccentricity index) in the BAV-AS group and more circular (smaller than normal eccentricity index) in the TAV-AS group