A novel technique to quantify the instantaneous mitral regurgitant rate

Abstract

BackgroundThe systolic variation of mitral regurgitation (MR) is a pitfall in its quantification. Current recommendations advocate using quantitative echocardiographic techniques that account for this systolic variation. While prior studies have qualitatively described patterns of systolic variation no study has quantified this variation.MethodsThis study includes 41 patients who underwent cardiovascular magnetic resonance (CMR) evaluation for the assessment of MR. Systole was divided into 3 equal parts: early, mid, and late. The MR jets were categorized as holosystolc, early, or late based on the portions of systole the jet was visible. The aortic flow and left ventricular stroke volume (LVSV) acquired by CMR were plotted against time. The instantaneous regurgitant rate was calculated for each third of systole as the difference between the LVSV and the aortic flow.ResultsThe regurgitant rate varied widely with a 1.9-fold, 3.4-fold, and 1.6-fold difference between the lowest and highest rate in patients with early, late, and holosystolic jets respectively. There was overlap of peak regurgitant rates among patients with mild, moderate and severe MR. The greatest variation of regurgitant rate was seen among patients with mild MR.ConclusionCMR can quantify the systolic temporal variation of MR. There is significant variation of the mitral regurgitant rate even among patients with holosystolic MR jets. These findings highlight the need to use quantitative measures of MR severity that take into consideration the temporal variation of MR.

A review of the pivotal role of cardiac MRI in mitral valve regurgitation

“…They concluded that there is significant variation of the mitral regurgitant rate even among patients with holosystolic MR jets and concluded that quantitative ways of assessing MR as suggested above via CMR effectively take into consideration this important confounding factor. A subsequent multicenter study determined that systolic variation is one of the factors that accounts for the discordance between echocardiographic and CMR assessment of MR, as the use of the color Doppler jet at a single point in time is the basis of many echocardiographic methods, and hence cannot factor in systolic variation 37,38 …”

Pivotal role of cardiac MRI in mitral valve regurgitation

“…A subsequent multicenter study determined that systolic variation is one of the factors that accounts for the discordance between echocardiographic and CMR assessment of MR, as the use of the color Doppler jet at a single point in time is the basis of many echocardiographic methods, and hence cannot factor in systolic variation. (34,35)Qualitative assessment of mitral valve anatomy and MR: When assessing mitral valve anatomy, the anterior and posterior leaflets, the annulus, the subvalvular apparatus (papillary muscles), and LV contractility including any regional wall motion abnormalities, are carefully visually assessed and their pathophysiology is commented upon. Abnormal leaflet morphology includes thickening, calcification, redundancy, perforation, vegetations, other masses and clefts.…”

Review of Journal of Cardiovascular Magnetic Resonance 2014

“…The design of arterial phantoms has proved useful for modelling [ 57 ]. The application of CMR to the assessment of valvular heart disease continues to increase, [ 58 ] particularly in aortic stenosis [ 59 – 61 ]. This is in part due to greater appreciation of its complementary roles in relation to echocardiography, which is commonly the first line investigative technique.…”