- Oral presentation
- Open Access
Quantification of aortic valve regurgitation by phase-contrast magnetic resonance in patients with bicuspid aortic valve: where to measure the flow?
© Muzzarelli et al; licensee BioMed Central Ltd. 2013
- Published: 30 January 2013
- Aortic Valve
- Flow Measurement
- Aortic Regurgitation
- Bicuspid Aortic Valve
- Ventricular Outflow Tract
Phase-contrast magnetic resonance (PC-MR) is used to quantify the aortic regurgitation (AR) by measuring the forward and backward flow in the ascending aorta (AAo), thereby quantifying the regurgitant fraction. Patients with bicuspid aortic valve (BAV) have an eccentric systolic aortic flow jet, causing an abnormal flow in the AAo. Therefore, we hypothesized that the flow measurement in the AAo in BAV patients leads to an underestimation of the forward aortic flow and a consequent overestimation of the AR.
Flow measurement by PC-MR was performed in 22 BAV patients and 20 controls at the following positions: 1) left ventricular outflow tract (LVOT), 2) aortic valve orifice (AV), and 3) AAo. The forward flow measured in these locations was compared with the left ventricular stroke volume (LVSV) in BAV patients and controls. Finally, the severity of the AR was quantified. Intravoxel dephasing was estimated by the ratio of the mean signal intensity on magnitude images across the vessel between systole and diastole.
Flow measurement in the AAo by PC-MR leads to a significant underestimation of the forward aortic flow and a consequent overestimation of the AR in BAV patients. Flow measurement in the LVOT or the AV better correlates with the LVSV, indicating an alternative means for quantifying the aortic regurgitation in BAV patients.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.