Quantitative assessment of MR is strongly recommended in the guidelines and the regurgitant volume and the effective regurgitant orifice area (EROA) of MR can be measured accurately and reproducibly by Doppler echocardiography. The EROA of MR has an important prognostic value in primary and secondary functional MR. Because functional MR carries an adverse prognosis with a graded relationship between MR severity and reduced survival, therapies that induce beneficial reverse remodeling of the LV and reduce MR, may improve survival. ACE inhibitors and ARBs could partially attenuate LV dilatation and remodeling after myocardial injury, but there are no published data from prospective trials regarding whether attenuation of remodeling by ACE inhibitors or ARBs reduces functional MR.