Transesophageal Echocardiographic Estmiation of Aortic Valve Area in Aortic Stenosis : A Comparison of Multiplane and Biplane Transesophageal Approach

ABSTRACT

BACKGROUND: There have been few reports in the literature evaluating aortic valve area by multiplane transesophageal echocardiography(M-TEE) as well as Biplane TEE(B-TEE) in comparison with transthoracic echocardiography(TTE) and cardiac catheterization(CC) estimated aortic valve area. The pupose of this study was to evaluate assessment of aortic valve area in patients with aortic stenosis by M-TEE compared to B-TEE and TTE. METHOD: 145 patients with known aortic valve stenosis underwent TTE, CC and intraoperative TEE assessment of the aortic valve area. 81 were done with multiplane only, 64 were done with biplane only. Results were compared with valve areas determined invasively by Gorlin formula and noninvasively by TTE using simplified continuity equation, TEE using direct planimetry and TEE proximal stenotic jet width. Aortic valve areas were also compared in sugically confirmed bicuspid and tricuspid aortic valves seperately. RESULTS: The feasibility of TTE, M-TEE, B-TEE and JW were 95.2%, 100%, 87.5% and 95.9%, respectively. Correlation between valve areas determined by Gorlin equation and M-TEE was the highest(r=0.89, n=81). This was higher for bicuspid valves(r=0.93, n=32) than tricuspid aortic valves(r=0.87, n=48). Correlations between the area determined by the Gorlin equation and that determined by B-TEE(r=0.74, n=56) and TTE(r=0.66, n=138) were lower. Coreelation for bicuspid and tricuspid were also lower(r=0.77, n=23, and r=0.75, n=30, respectively in biplane assessment, and r=0.71, n=61, and r=0.65, n=73, respectively in TTE assessment). Correlation of invasively determined valve areas with JW was lowest(r=0.57, n=139) though bicuspid valve area correlated better(r=0.64, n=60)than tricuspid aortic valves(r=0.53, n=75). CONCLUSION: M-TEE is superior to B-TEE in the assessment of aortic valve stenosis. Bicuspid aortic valve areas were accurately measured more consistently than tricuspid aortic valve areas. M-TEE can be used addiotional method to evaluate aortic valve area with conventional TEE and cardiac catheterization.