Accuracy and feasibility of a simplified approach to assess the regurgitant orifice area in patients with mitral regurgitation.

BACKGROUND

Regurgitant orifice area (ROA) has been proposed as a marker of severity in patients with mitral regurgitation (MR). However, such fundamental quantitative echocardiographic parameter has failed to achieve widespread use, since it is difficult to measure. In the present study, we evaluated the accuracy and feasibility of a simplified method for quantification of ROA in patients with varying grades of MR.

METHODS

We studied two groups of individuals with echocardiographically diagnosed MR. Group I included 70 patients retrospectively evaluated, in whom we were able to obtain an adequate flow convergence region by color Doppler and recording of continuous-wave Doppler regurgitant jet. Group II included 32 MR patients prospectively evaluated. The degee of MR was assessed by two quantitative echocardiographic measures: the regurgitant fraction and the ROA, calculated either dividing peak flow rate by the maximal velocity through the orifice or with the simplified formula: r2/2.

RESULTS

In group I, the mechanism of MR was organic in 18 patients and ischemic/functional in 52 patients. ROA calculated by the simplified formula correlated well with the conventional one (r = 0.85) and with the regurgitant fraction (r = 0.72). In group II, we could calculate the ROA by the conventional method in 56% of patients, whereas use of the simplified approach allowed ROA evaluation in 78% of patients.

CONCLUSION

Our data suggest that the use of a simplified formula may increase the number of patients having ROA, a fundamental parameter of MR severity, measured in clinical practice.