In a head-to-head comparison with velocity-encoded 3D cardiac MR to measure mitral regurgitation, real-time 3D echocardiography proved feasible and accurate. In addition, researchers found that the currently recommended 2D echo approach significantly underestimated both the effective regurgitant orifice area and the regurgitant volume.
Nina Ajmone Marsan, MD, and colleagues from Leiden University Medical Center, the Netherlands, evaluated 70 consecutive patients who were clinically referred for cardiac MR and had functional mild-to-severe mitral regurgitation on color Doppler echo. Six patients were excluded from the final analysis due to inadequate 3D echo images.
The authors state that 3D cardiac MR has recently been proposed to serve as a reference method for grading the severity of mitral regurgitation.
The study appears in the current issue of the Journal of the American College of Cardiology: Cardiovascular Imaging.
The main findings of the study, according to the authors, are that the 3D echo measurements were reproducible, 2D echo systematically underestimated the effective regurgitant orifice area, and the difference between the 2D and 3D echo techniques was more accentuated in the presence of an asymmetric regurgitant orifice.
The investigators also emphasized that real-time 3D echo correlated well with cardiac MRI regarding measurement of regurgitant volume, while 2D echo significantly underestimated regurgitant volume compared with MRI.
“The presence of functional MR has important prognostic value, and accurate assessment of its severity is crucial for risk stratification and clinical decision-making,” according to the authors.
They concluded that real-time 3D echo might be proposed as a better alternative to conventional 2D echo.