Clinical value of parameters derived by the application of the proximal isovelocity surface area method in the assessment of mitral regurgitation

To determine the clinical value of several parameters derived by applicatio n of the proximal isovelocity surface area method in the assessment of mitr al regurgitation (MR), 28 consecutive patients with angiographic diagnosis of MR underwent color Doppler echocardiography within 38 h of cardiac cathe terization. Aliasing velocities (V-N) were baseline-shifted to 25 cm/s and the maximal radius (R) was measured from the first aliasing boundary to the tips of the mitral valve. By continuity, the regurgitant orifice area (ROA ) and regurgitant stroke volume (RSVPISA) were obtained. We have related th em to the angiographic grade, and with determination of the regurgitant str oke volume (RSVDE) and the regurgitant fraction (RF), we calculated the vol ume of the transmitral flow according to Fisher's method. Results: RSVDE co rrelated well with RSVPISA (r=0.98). A clear relation existed between the i sovelocity radius and the RSVDE and RF (r=0.95 and 0.88, respectively). A r adius of 8 mm or more was identified well with an RSVDE of 40 cm(3) or more (sensitivity: 100%, specificity: 95%) and an RF of 35% or more (sensitivit y: 88%, specificity: 94%). The ROA was closely related to the more and RF v alues of 35% or more, The radius, RSVPISA and ROA were closely related to t he angiographic grade of MR (r=0.91, 0.83 and 0.92, respectively). A radius of 7 mm or more identified patients with grade III or IV of regurgitation (sensitivity: 82%, specificity: 94%), while an ROA of 15 mm(2) or more disc riminated well significant regurgitation (sensitivity: 91%, specificity: 94 %). Conclusions: parameters derived by application of the proximal isoveloc ity surface area method provide quantitative information that can be helpfu l in predicting the severity of mitral regurgitation noninvasively. (C) 199 9 Elsevier Science Ireland Ltd. All rights reserved.