843 QUANTIFICATION OF VENTRICULAR FUNCTIONAL MITRAL REGURGITATION USING THE VOLUMETRIC METHOD BY 3D-ECHOCARDIOGRAPHY

Abstract Background ventricular functional mitral regurgitation (v-FMR) is associated with an increased risk of mortality and hospitalization for heart failure. In this setting, the echocardiographic assessment v-FMR severity using 2D proximal isovelocity surface area (PISA) yields several limitations, potentially leading to underestimation severity. An alternative approach derive regurgitant volume (RegVol) effective orifice (EROA) three-dimensional echocardiography (3DE) estimate left volumes (volumetric method, VM). However, a direct comparison these methods has never been tested. Accordingly, aims our study are: i; compare both PISA measurements EROA RegVol those obtained by VM 3DE, ii; test their accuracy 3D planimetry vena contracta (3D-VCA) MR jet, as reference. Methods we retrospectively analysed 82 (mean age 75±12, 48% men, 79% sinus rhythm, 85% ischemic cardiomyopathy, 15% dilated cardiomyopathy) consecutive patients reduced ejection fraction (LVEF <50%), acquired between July 2020 October 2021. Exclusion criteria were: < 18 years, primary MR, presence intra-cardiac shunts, greater than mild aortic regurgitation, inadequate acoustic window. was calculated formula: 6.28 r2×Va/Vp (where: r= radius, Va= aliasing velocity, Vp= peak velocity). FMR EROA×VTIMR, where VTIMR represents time–velocity integral CW Doppler jet tracing. 3DE volumetric method (VM) as: total LV stroke (LV SV) – forward SV (Ao SV). subtracting respective end-systolic (ESV) from end-diastolic (EDV) measured 3DE. Ao multiplying outflow tract velocity time (VTI). divided VTIMR. group 10 patients, quantification 3D-VCA performed multiplanar reconstruction dedicated software package (EchoPAC 204 GE Vingmed, Horten, Norway). Results average volumes, volume, LVEF global longitudinal strain were 211±25 mL, 134±17 73±9 36±8% and, 9.4±2.7% respectively. Median 50±12 mL. Left atrial reservoir respectively 99±19 mL 10±16%. Both larger (0.17± 0.09 cm2 vs 0.11± 0.01 cm2; p<0.001) (25.7±12.1 17.2±9.9 mL; PISA, Compared 3D-VCA, resulted more accurate (bias= -0.15 cm2, LOA ±0.24 bias= -0.25 ±0.29 cm2). Finally, (r= 0.778) showed better correlation 0.681) (p<0.001). Conclusions in v-FMR, values compared conventional closer VCA. could improve evaluation Larger studies longer clinical follow-up are needed define if it translates into improved stratification may address patients’ management.