Avaliação da Área Valvar Aórtica Combinando Ecocardiografia e Ressonância Magnética Assessment of Aortic Valve Area Combining Echocardiography and Magnetic Resonance Imaging

Abstract Background: Transthoracic echocardiography (TTE) is routinely used to calculate aortic valve area (AVA) by continuity equation (CE). However, accurate measurement of the left ventricular outflow tract (LVOT) can be difficult and flow acceleration in the LVOT may lead to miscalculation of the AVA. Objective: The aim of our study was to compare AVA measurements by standard TTE, cardiac magnetic resonance imaging (MRI) and a hybrid approach combining both techniques. Methods: AVA was calculated in 38 patients (age 73±9 years) with standard TTE, cine-MRI planimetry and a hybrid approach: Hybrid Method 1: TTE-derived LVOT measurement in the CE numerator was replaced by the MRI assessment of the LVOT and AVA was calculated: (LVOT MRI /*LVOT-VTI TTE )/transaortic-VTI TTE . Method 2: We replaced the SV in the numerator by the MRI-derived SV and calculated AVA = SV MRI / transaortic-VTI TTE . Results: 2 Mean AVA derived by TTE was 0.86 cm ±0.23 cm 2 and 0.83 cm 2 ±0.3 cm 2 by MRI- planimetry, respectively. The mean absolute difference in AVA was 0.03cm