A pairwise meta-analytic comparison of aortic valve area determined by planimetric versus hemodynamic methods in aortic stenosis

Background: Aortic valve area (AVA) is commonly determined from 2-dimensional transthoracic echocardiography (2D TTE) by the continuity equation; however, this method relies on geometric assumptions of the left ventricular outflow tract which may not hold true. This study compared mean differences and correlations for AVA by planimetric (2-dimensional transesophageal echocardiography [2D TEE], 3-dimensional transesophageal echocardiography [3D TEE], 3-dimensional transthoracic echocardiography [3D TTE], multi-detector computed tomography [MDCT], and magnetic resonance imaging [MRI]) with hemodynamic methods (2D TTE and catheterization) using pairwise meta-analysis. Method: Ovid MEDLINE (R), Ovid EMBASE, and The Cochrane Library (Wiley) were queried for studies comparing AVA measurements assessed by planimetric and hemodynamic techniques. Pairwise meta-analysis for mean differences (using random effect model) and for correlation coefficients (r) were performed. Results: Forty-five studies (3014 patients) were included. Mean differences between planimetric and hemodynamic techniques were 0.12 cm(2) (95%CI 0.10-0.15) for AVA (pooled r = 0.84; 95%CI 0.76-0.90); 1.36cm(2) (95% CI 1.03-1.69) for left ventricular outflow tract area; and 0.13 cm (95%CI 0.07-0.20) for annular diameter (pooled r = 0.76; 95% CI 0.64-0.94); 0.67 cm(2) (95%CI 0.59-0.76) for annular area (pooled r = 0.74; 95%CI 0.55-0.86). Conclusions: Planimetric techniques slightly, but significantly, overestimate AVA when compared to hemodynamic techniques. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

This study compared different imaging techniques for measuring aortic valve area and found that planimetric techniques tend to overestimate the area when compared to hemodynamic methods, which may have implications for clinical diagnosis and management.