Quantification of Mitral Regurgitation by General Imaging Three-Dimensional Quantification: Feasibility and Accuracy

Background: Mitral regurgitant volume (MRvol) is an important index of the severity of mitral regurgitation (MR), but MRvol measurement remains challenging. With the development of probe technology and software, General Imaging 3D Quantification (GI 3DQ) allows the direct measurement of MR jet volume. The aim of this study was to evaluate the feasibility and accuracy of MRvol by quantification of MR jet volume using GI 3DQ. Methods: Ninety-three patients were included, 61 with functional MR and 32 with mitral valve prolapse. Patients with MR were also divided into those with central MR (n = 41) and those with eccentric MR (n = 52). MRvol was assessed using GI 3DQ and the proximal isovelocity surface area (PISA) method. MRvol using effective regurgitant orifice area by real-time three-dimensional echocardiography multiplied by the MR time-velocity integral was used as the reference method. Results: MRvol measured by GI 3DQ and the PISA method had good correlation with MRvol by the reference method. A significant underestimation of MRvol using GI 3DQ and the PISA method was observed in the assessment of eccentric MR, but without a significant difference in the assessment of central MR. Conclusions: Quantification of MRvol with GI 3DQ was feasible. Quantification of central MRvol using this methodology is accurate compared with the reference method. Quantification of MRvol with GI 3DQ has no significant difference from the currently recommended PISA method.