Severity of aortic regurgitation: interstudy reproducibility of measurements with velocity-encoded cine MR imaging.

Abstract

The interstudy reproducibility of velocity-encoded cine (VEC) magnetic resonance (MR) imaging for quantification of regurgitant volume (RV) and regurgitant fraction (RF) was studied in 10 patients with chronic aortic regurgitation. Each patient underwent two VEC MR imaging studies. RV and RF were measured on the aortic flow curve by quantifying antegrade and retrograde flow per cardiac cycle. VEC MR imaging measurements for RV and RF correlated closely with volumetric measurements for both studies (r greater than .97). Interstudy reproducibility for VEC MR imaging measurement of RV and RF was high (r greater than .97), and the interstudy variability for VEC MR imaging measurements was low. These results demonstrate a high accuracy of VEC MR imaging for measurement of RV and RF in patients with chronic aortic regurgitation. The level of interstudy reproducibility of VEC MR imaging for quantitative assessment of RV and RF indicates the potential of this technique for follow-up and monitoring of response to therapy.

Comparison of myocardial velocities obtained with magnetic resonance phase velocity mapping and tissue doppler imaging in normal subjects and patients with left ventricular dyssynchrony

“…However, the validity of TDI for measuring velocity and time to peak velocity in patients with conduction system disease has gained wide acceptance without validation by other velocity imaging techniques. MR-PVM has been shown to accurately and reproducibly measure blood velocity in imaging phantoms (errors Ͻ 1.6% from true) (20,30,31). Coronary flow velocity by Doppler flow wire correlates well with MR measurements of blood velocity (r ϭ 0.913), and cine MR and MR-PVM agree in the determination of regurgitant fraction and volume in patients with mitral regurgitation (31).…”

Quantification of mitral regurgitation with MR phase‐velocity mapping using a control volume method

“…This quantity has been identified as an important index of the severity of regurgitation. Vol umetric MRI techniques (11,12) attempted to measure the regurgitant volume from the difference between the left and right ventricular stroke volumes. Although the combination of left and right ventricular volumes with systolic and diastolic aortic and pulmonic flows can pro vide an estimate for the regurgitant volumes of the heart valves, this approach is not reliable in the presence, for instance, of aortic and pulmonic valve stenosis because of signal distortion in the aorta and pulmonary artery.…”

The emerging clinical role of cardiovascular magnetic resonance imaging

“…This allows for the calculation of regurgitant volume and regurgitant fraction. The method is highly reproducible (98), and the results agree well with aortic root angiography (94). Similar principles are applied to the assessment of the mitral and right-sided heart valves (95,99,100).…”