Comments on: Quantification of Functional Mitral Regurgitation by Real-Time 3D Echocardiography: Comparison With 3D Velocity-Encoded Cardiac Magnetic Resonance http://www.thepreparedminds.com/archives/543 In the field of observation, chance favors the prepared minds. Sat, 04 Feb 2012 14:45:45 +0000 hourly 1 http://wordpress.org/?v=3.3 By: Cleveland Clinic Florida Journal Club http://www.thepreparedminds.com/archives/543/comment-page-1#comment-628 Cleveland Clinic Florida Journal Club Fri, 25 Dec 2009 21:17:04 +0000 http://www.thepreparedminds.com/?p=543#comment-628 Echocardiography continues to be the most important and practical tool in the assessment of mitral regurgitation. Over the past few years, more emphasis has been placed on the quantitative analysis of valvular heart disease. Evaluation of the effective regurgitant orifice area (EROA) and regurgitant volume (Rvol) have demonstrated not only to provide an assessment of mitral regurgitation severity but also provide prognostic information. For this reason, a quantitative approach in the evaluation of mitral regurgitation is recommended. This can be done with 2-d echocardiography by using the proximal isovelocity surface area (PISA) which can help us derive an EROA and Rvol, or can also help us perform a more direct assessment with the vena contracta width. However, prior studies have already demonstrated that the geometry of the EROA is complex and asymmetric. A three dimensional echocardiographic approach, especially by utilizing an “en face” view, can provide a more accurate estimation of the EROA. The investigators compared quantitative echocardiography (2d and 3d) with 3-directional velocity encoded MRI. The following were the conclusions of the study: first of all, the quantitative analysis of mitral regurgitation by 3d echocardiography was feasible and reproducible. Secondly, there was a consistent underestimation of EROA by 2d echocardiography when compared with real time 3d echocardiography, especially in those patients with the most asymmetric EROA. Third, there was a strong correlation between 3d echocardiography quantitative values and those calculated with MRI. Conclusions: - Echocardiography continues to be the preferred and most practical method of assessment of mitral regurgitation. - This study adds to the growing evidence supporting the use of three dimensional echocardiography for the quantitation of mitral regurgitation. - The vena contracta width (4-chamber and 2-chamber views) is not routinely used to estimate the EROA. - The comparison results between 2d echocardiography and 3d echocardiography might have been different should the PISA method would have been used. - As of today, it is unlikely that a patient will be referred for a cardiac MRI exclusively for the assessment of mitral regurgitation. The current study showed an excellent correlation between 3d echocardiography and VE-CMR in the estimation of regurgitant volumes. - The same group that did this study <a href="http://www.ncbi.nlm.nih.gov/pubmed/18849503" rel="nofollow">published</a> their findings when comparing the more commonly used 2D (single direction) phase contrast MRI vs. 3D phase contrast MRI technique, and showed a slight overestimation (15%) of mitral valve flow of 2D measurements when compared with 3D. When is this overestimation clinically significant to require the use of longer, more effort-consuming 3D techniques? Probably in a very small number of selected patients. Echocardiography continues to be the most important and practical tool in the assessment of mitral regurgitation. Over the past few years, more emphasis has been placed on the quantitative analysis of valvular heart disease. Evaluation of the effective regurgitant orifice area (EROA) and regurgitant volume (Rvol) have demonstrated not only to provide an assessment of mitral regurgitation severity but also provide prognostic information. For this reason, a quantitative approach in the evaluation of mitral regurgitation is recommended. This can be done with 2-d echocardiography by using the proximal isovelocity surface area (PISA) which can help us derive an EROA and Rvol, or can also help us perform a more direct assessment with the vena contracta width. However, prior studies have already demonstrated that the geometry of the EROA is complex and asymmetric. A three dimensional echocardiographic approach, especially by utilizing an “en face” view, can provide a more accurate estimation of the EROA.

The investigators compared quantitative echocardiography (2d and 3d) with 3-directional velocity encoded MRI.
The following were the conclusions of the study: first of all, the quantitative analysis of mitral regurgitation by 3d echocardiography was feasible and reproducible. Secondly, there was a consistent underestimation of EROA by 2d echocardiography when compared with real time 3d echocardiography, especially in those patients with the most asymmetric EROA. Third, there was a strong correlation between 3d echocardiography quantitative values and those calculated with MRI.

Conclusions:

- Echocardiography continues to be the preferred and most practical method of assessment of mitral regurgitation.
- This study adds to the growing evidence supporting the use of three dimensional echocardiography for the quantitation of mitral regurgitation.
- The vena contracta width (4-chamber and 2-chamber views) is not routinely used to estimate the EROA.
- The comparison results between 2d echocardiography and 3d echocardiography might have been different should the PISA method would have been used.
- As of today, it is unlikely that a patient will be referred for a cardiac MRI exclusively for the assessment of mitral regurgitation.
The current study showed an excellent correlation between 3d echocardiography and VE-CMR in the estimation of regurgitant volumes.
- The same group that did this study published their findings when comparing the more commonly used 2D (single direction) phase contrast MRI vs. 3D phase contrast MRI technique, and showed a slight overestimation (15%) of mitral valve flow of 2D measurements when compared with 3D. When is this overestimation clinically significant to require the use of longer, more effort-consuming 3D techniques? Probably in a very small number of selected patients.

]]> By: Jacobo Kirsch, MD http://www.thepreparedminds.com/archives/543/comment-page-1#comment-472 Jacobo Kirsch, MD Mon, 23 Nov 2009 15:09:45 +0000 http://www.thepreparedminds.com/?p=543#comment-472 This is a very well-designed study on 64 continuous patients with functional mild-to-severe MR. It shows Real-Time 3d echo to be a feasible and reproducible mean for directly assessing MR when compared with MRI. Additionally, 2D echocardiography (currently the most commonly used test) was also compared revealing it to underestimate the MR measurements, especially when asymmetric regurgitant orifices were present. While methodologically this is an important manuscript, its clinical significance and the effect that using RT3DE will have in patient treatment and outcome needs to be investigated. This is a very well-designed study on 64 continuous patients with functional mild-to-severe MR.
It shows Real-Time 3d echo to be a feasible and reproducible mean for directly assessing MR when compared with MRI. Additionally, 2D echocardiography (currently the most commonly used test) was also compared revealing it to underestimate the MR measurements, especially when asymmetric regurgitant orifices were present.
While methodologically this is an important manuscript, its clinical significance and the effect that using RT3DE will have in patient treatment and outcome needs to be investigated.

]]> By: Paul Schoenhagen, MD http://www.thepreparedminds.com/archives/543/comment-page-1#comment-388 Paul Schoenhagen, MD Sat, 14 Nov 2009 16:31:34 +0000 http://www.thepreparedminds.com/?p=543#comment-388 See related <a href="http://www.thepreparedminds.com/archives/566" rel="nofollow">post</a> from November 14: Real-time three-dimensional transoesophageal echocardiography in the assessment of aortic valve stenosis. See related post from November 14: Real-time three-dimensional transoesophageal echocardiography in the assessment of aortic valve stenosis.

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