Regurgitant Volume/Left Ventricular End-Diastolic Volume Ratio: Prognostic Value in Patients With Secondary Mitral...

The purpose of this study was to investigate the prognostic implications of the ratio of mitral regurgitant volume (RVol) to left ventricular (LV) end-diastolic volume (EDV) in patients with significant secondary mitral regurgitation (MR).

Quantification of secondary MR remains challenging, and its severity can be over- or underestimated when using the proximal isovelocity surface area method, which does not take LV volume into account. This limitation can be addressed by normalizing mitral RVol to LVEDV.

A total of 379 patients (mean age 67 ± 11 years; 63% male) with significant (moderate and severe) secondary MR were divided into 2 groups according to the RVol/EDV ratio: RVol/EDV ≥20% (greater MR/smaller EDV) and <20% (smaller MR/larger EDV). The primary endpoint was all-cause mortality.

During median (interquartile range) follow-up of 50 (26 to 94) months, 199 (52.5%) patients died. When considering patients receiving medical therapy only, patients with RVol/EDV ratio ≥20% tended to have higher mortality rates than those with RVol/EDV ratio <20% (5-year estimated rates 24.1% vs. 18.4%, respectively; p = 0.077). Conversely, when considering the entire follow-up period including mitral valve interventions, patients with a higher RVol/EDV ratio (≥20%) had lower rates of all-cause mortality compared with patients with RVol/EDV ratio <20% (5-year estimated rates 39.0% vs. 44.8%, respectively; p = 0.018). On multivariable analysis, higher RVol/EDV ratio (per 5% increment as a continuous variable) was independently associated with lower all-cause mortality (0.93; p = 0.023).

In patients with significant secondary MR treated medically, survival tended to be lower in those with a higher RVol/EDV ratio. Conversely, a higher RVol/EDV ratio was independently associated with reduced all-cause mortality. when mitral valve interventions were taken into consideration.