Usefulness of the mitral/aortic flow velocity integral ratio as a screening method to identify patients with hemodynamically significant mitral regurgitation.

Objective: We sought to test the value of a simple Doppler index, the mitral/aortic flow velocity integral ratio (MAVIR), as a screening method to identify patients with hemodynamically significant mitral regurgitation (MR).
Methods: Included in the study were 91 patients (mean age 61 +/- 14 years; 54% men) with echocardiographically diagnosed MR. The cause was organic in 23 patients and ischemic/functional in 68. MR degree was assessed by 2 quantitative echocardiographic measures: the regurgitant fraction and the regurgitant orifice area.
Results: A good correlation was found between MAVIR and both regurgitant fraction (r = 0.75) and orifice (r = 0.60). When we divided patients into 3 groups on the basis of the regurgitant fraction, used as reference standard, MAVIR significantly increased in proportion to MR severity (0.7 +/- 0.1 for mild MR vs 1.1 +/- 0.2 for moderate and 1.4 +/- 0.3 for severe regurgitation; P <.0001). A ratio > 1 identified 28 of 30 patients with severe MR (regurgitant fraction > 60%), whereas all patients with mild MR (regurgitant fraction < 40%) had a ratio < 1. Using a regurgitant orifice >or= 40 mm(2) as threshold for severe MR, a significant difference in MAVIR was also present among patients who had severe MR compared with those having mild and moderate regurgitation (P <.0001).
Conclusions: These findings suggest that MAVIR is a sensitive index, potentially widely applicable in clinical practice as a screening parameter for identifying patients with hemodynamically significant MR.