Aortic valve area determination by planimetry: comparison of two-dimensional and three-dimensional transesophageal echocardiography – a systematic review and meta-analysis

INTRODUCTION: Accurate quantification of aortic valve area (AVA) is essential in the evaluation of aortic stenosis (AS) severity. While two-dimensional (2D) Transesophageal echocardiography (TEE) is widely used for AVA planimetry, three-dimensional (3D) TEE may offer superior accuracy due to improved anatomical visualization. We aimed to compare AVA measurements by 2D versus 3D TEE in patients with AS. METHODS: We conducted a systematic review and meta-analysis of studies reporting AVA measurements using both 2D and 3D TEE in adult patients with AS. Paired measurements, means and standard deviations, or correlations between techniques were extracted. The primary outcome was the mean difference in AVA (cm²) between modalities. Secondary outcomes included pooled correlation coefficients and assessment of heterogeneity. Analyses were performed using random-effects models. Eight studies comprising 381 patients were included. The pooled mean absolute difference between 2D and 3D TEE was 0.16 cm² (95% CI 0.09-0.23; p < 0.001), indicating that 3D TEE yielded slightly smaller AVA measurements overall, with a tendency to lower interobserver variability. Heterogeneity was low, and sensitivity analyses excluding older equipment showed consistent findings. Most studies demonstrated low risk of bias in patient selection and flow/timing, with some concerns regarding index-test and reference-standard domains. CONCLUSIONS: 3D TEE provides slightly smaller AVA measurements than 2D TEE, with low heterogeneity and acceptable study quality. While both modalities may be clinically useful, 3D TEE may offer more reliable anatomical assessment. Standardized imaging protocols and multicenter validation are warranted to enhance reproducibility and ensure consistent evaluation of AS severity.