Abstract #1329

A Novel Method for the Assessment of Valve Effective Orifice Area Using 4D Flow Shear Layer Detection Method in Patients with Aortic Stenosis

Julio Garcia¹, Michael Markl¹,², Susanne Schnell¹, Pegah Entezari¹, Riti J. Mahadevia¹, Can Wu¹, Chris Malaisrie³, Philippe Pibarot⁴, James C. Carr¹, Alex J. Barker¹

¹Radiology, Northwestern University, Chicago, IL, United States; ²Biomedical Engineering, Northwestern University, Chicago, IL, United States; ³Division of Cardiac Surgery, Northwestern University, Chicago, IL, United States; ⁴Department of Medicine, Laval University, Quebec, Canada

Valve aortic stenosis (AS) is the most common cause of valvular replacement. The AS severity is mainly evaluated by transthoracic Doppler echocardiography (TTE) by measuring transvalvular velocity gradients and valve effective orifice area (EOA). In particular, valve EOA has high variability when measured by TTE. 3D time-resolved phase contrast MRI with 3-directional velocity encoding may improve EOA estimation by leveraging the advantages of a novel jet shear layer detection (JSLD) method for estimating valve EOA. The objective of this study was to validate 4D flow MRI-based EOA estimation using an in-vitro stenosis phantom and in-vivo measurements of the JSLD-determined EOA.