Mitral Regurgitant Volume Research Articles

Abstract 16771: Longitudinal Segmental Shape Analysis of the Remodeling Left Ventricle in Chronic Mitral Regurgitation

Introduction: Severe mitral regurgitation (MR) initiates left ventricular (LV) dilatation, but preserves systolic function. Due to preserved EF, patients are not referred for correction of their MR, and the ventricle continues to enlarge. Identifying patients at risk of heart failure, just from assessing LV size is challenging. In this study, we sought to investigate if ventricular shape and sphericity can represent the pathological remodeling process in this disease. Methods: Sixty adult rats (N=60) were induced with severe MR by puncturing the mitral valve leaflet with a 23G needle on the beating heart, using echo guidance (Fig.A1). Transthoracic echocardiography was performed at 2, 10, 20, and 40 weeks (n=15 rats/group) for analysis of the left ventricular shape. Fifteen healthy rats (N=15) were used as a sham group for comparison. Results: Severe MR was confirmed in all the rats in the MR group with a MR jet area of 40.99±9.40% ( Fig.A2 ), MR volume of 119.50±32.43μl ( Fig.A3 ), and pulmonary flow reversal ( Fig.A4 ). None of these were observed in the control group. LV dilation was observed in MR rats compared to sham ( Fig.B ). Diastolic sphericity index, LV area, and diastolic apical area index was significantly increased at 2, 10, 20, and 40 weeks after MR compared to sham (p<0.05) ( Fig.C1-C3 ). Systolic sphericity index was not significantly increased compared to sham at any time-point ( Fig.D1 ). LV area was unchanged at 2 weeks, and was significantly increased at 10, 20, and 40 weeks ( Fig.D2 ). Systolic apical area index was significantly increased at 2, 20, and 40 weeks compared to sham (p<0.05) ( Fig.D3 ). Conclusions: Analysis of left ventricular shape and its longitudinal changes can help detect remodeling patterns that are not visible using traditional functional indices.

Impact of transcatheter aortic valve implantation on coexistent mitral regurgitation parameters.

Data on the impact of transcatheter aortic valve implantation (TAVI) on coexisting mitral regurgitation (MR) are still inconsistent. The study aimed to evaluate the impact of TAVI on coexistent MR depending on its etiology. Out of 311 patients treated with TAVI, we selected 48 with coexistent MR: functional (FMR; n = 26) or nonfunctional (nFMR; n = 22). The impact of the procedure on MR was quantitatively assessed during a 1‑year follow‑up using MR effective regurgitant orifice area (MR‑EROA) and volume (MRV). Compared with baseline, no change of MR‑EROA was observed at 1‑year follow‑up in all patients with MR (median [interquartile range (IQR)], 0.2 [0.17-0.23]cm2 vs 0.17 [0.14-0.2]cm2 ; P = 0.054). No change in MR‑EROA was also noted either in FMR (median [IQR], 0.21 [0.17-0.27]cm2 vs 0.19 [0.14-0.25]cm2 ; P = 0.142) or nFMR (median [IQR], 0.17 [0.12-0.23] cm2 vs 0.17 [0.1-0.2] cm2 ; P = 0.238) cohorts. Decreased MRV was seen in theoverall MR population after TAVI (median [IQR], 32 [28-36]ml/beat vs 26 [22-28]ml/beat; P = 0.002). Similarly, decreased MRV was noted in both FMR (median [IQR], 33 [26-42] ml/beat vs 26 [20-40] ml/beat; P = 0.042) and nFMR (median [IQR], 30 [20-46] ml/beat vs 24 [15-33] ml/beat; P = 0.015) cohorts. Transcatheter aortic valve implantation had no impact on MR‑EROA regardless of the etiology of regurgitation. However, the procedure reduced MRV in both FMR and nFMR.

How accurate is cardiac magnetic resonance in quantitation of primary mitral regurgitation?

Abstract Background Since evaluation of mitral regurgitation (MR) in patients with mitral prolapse by echo may be challenging, cardiac MRI (CMR) has been used for identification of patients with severe valve disease. Little is known about potential factors influencing accuracy of this approach. Purpose To study the impact of left ventricular (LV) contouring methods and interobserver variability on quantitation of MR severity. Methods A total of 50 asymptomatic patients with echocardiographically moderate or severe MR were included to LV-REGURGE study and evaluated with CMR by two independent reviewers. LV volumes were calculated on SSFP short axis stack including or excluding intracavitary myocardium into/from the LV volume (“including” or “excluding” method, respectively). Aortic flow volumes were obtained using phase contrast method. Mitral regurgitant volume (RegVol) was calculated by subtracting forward aortic volume from LV stroke volume. Severe MR was diagnosed when RegVol >60mL and/or RegVol/LV stroke volume (RF) >40%. Agreement between MR grading into severe and non-severe, obtained by different tracing methods and different reviewers was assessed using kappa coefficient. Results Left ventricular and mitral regurgitant volumes obtained by “including” method were significantly larger as compared with “excluding” method, see table. “Including” method identified severe MR in 68% while “excluding” method in 57% of cases. Overall agreement between the methods was present in 84% of cases, meaning a substantial rate of agreement (κ 0.67). Within respective methods, interobserver agreement was present in 77% of cases, interpreted as a moderate rate of agreement (κ 0.48–0.54) Conclusion “Including” trabeculae and papillary muscles into the LV cavity volume substantially increases rate of recognizing severe MR, due to larger LV volumes, particularly LV ESV, comparing with the “excluding” method. Moreover, inter-observer variability in similar extent as tracing method seems to impact differentiation between severe and non-severe MR. Funding Acknowledgement Type of funding source: None

Determinants and prognostic significance of focal myocardial fibrosis by cardiac magnetic resonance imaging in patients with mitral valve prolapse

Abstract Background Mitral valve prolapse (MVP) is a frequent disease that can be complicated by mitral regurgitation (MR), heart failure, arterial embolism, rhythm disorders and death. Purpose We sought to evaluate the correlates of late gadolinium enhancement (LGE), and the prognostic significance of ventricular size, function, and LGE by cardiac magnetic resonance (CMR) imaging on cardiovascular morbi-mortality in patients with MVP Methods We included 426 patients (54±15 years, 57% male) with MVP (trace to severe MR) between 2010 and 2019 who underwent a comprehensive echocardiography and CMR imaging. Gadolinium was injected in 411 (96%) patients. The main outcome endpoint was a composite endpoint of cardiovascular death, heart failure, new onset atrial fibrillation or arterial embolism, censored at the time of mitral valve intervention. Results Among the 411 patients, LGE+ was found in 118 (29%; 100 myocardial wall including 78 basal inferolateral midwall, 30 papillary muscles) and was more frequent with worse MR volume and LV remodeling. Correlates of LGE in multivariable analysis were LV mass index (OR 1.02, P=0.008), moderate-severe MR (OR 2.15, P=0.017) and coronary artery disease (OR 5.8, P=0.013). At 4 years, survival without cardiovascular events was decreased in patients with LGE+ (50.0±11.9 vs 73.5±6.3%, p<0.0001). In a stepwise multivariable analysis including classical predictors of outcome, grade of MR, LA volume index and the presence of LGE on CMR imaging (HR: 2.15 [1.15–4.02], P=0.017) were associated with impaired event-free survival. Conclusion CMR imaging provides additional information to echocardiography in the clinical work-up of MVP. Localized LV myocardial fibrosis is a predictor of cardiovascular event in MVP patients. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): DGOS (PHRCI), Fondation Cœur et Recherche

Right ventricular reserve post mitral valve repair is associated with heart failure hospitalization.

Right ventricular impairment is a predictor of cardiovascular outcomes in patients with degenerative mitral regurgitation. However, the time course of right ventricular functional changes post-surgical mitral valve repair remains largely unknown. Herein, using right ventricular-focused echocardiography, we aimed to investigate right ventricular reserve and its impact on hospitalization for heart failure after mitral valve repair. In this prospective study, we enrolled 108 patients scheduled to undergo surgical repair of degenerative mitral regurgitation. Echocardiography, including right ventricular strain analysis, was performed prior to, and one month and six months post mitral valve repair. Right ventricular strain that improved one month post-surgery was defined as reserved right ventricular. In addition, any cardiovascular outcomes comprising heart failure that required admission were recorded. The median follow-up duration is 31 months. Despite a significant improvement in mitral valve regurgitant volume post-operatively, left ventricular ejection fraction (LVEF) at six months was similar to LVEF at baseline. There was a transient decrease in LV longitudinal strain at one month that was recovered six months post mitral valve repair. Regarding the right ventricular, in contrast with conventional right ventricular parameters, including right ventricular tissue Doppler S', fractional area change and tricuspid annular plane systolic excursion (TAPSE), only resolution of right ventricular strain at one month predicted the subsequent myocardial recovery. Furthermore, patients with reserved right ventricular had a lower risk of hospitalization for heart failure compared to those with non-reserved right ventricular. Collectively, the early resolution of right ventricular strain is associated with the improvement in right ventricular function (measured by TAPSE) and in heart failure hospitalization in patients who had undergone surgical mitral valve repair for degenerative mitral regurgitation.

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

ObjectivesThe 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). BackgroundQuantification 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. MethodsA 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. ResultsDuring 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). ConclusionsIn 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

Automated quantification of mitral valve tenting volume in functional mitral regurgitation by three-dimensional echocardiography.

Tenting of the mitral leaflets is a major pathophysiological factor contributing to functional mitral regurgitation (FMR). A novel software tool allows automated quantification of the tenting volume (TnV) by 3D transesophageal echocardiography (TEE). The aims of this study are to investigate the correlations of biometric patient characteristics with the TnV and whether a threshold value for the diagnosis of a moderate or severe FMR can be calculated for the TnV. This explorative and hypothesis-generating study analyzed the TnV of the mitral valve obtained by clinically indicated TEE. The mid-systolic, threefold calculated and averaged TnV from 80 patients with no or mild FMR and 27 patients with moderate or severe FMR was determined using the TomTec 4D MV Assessment tool. The TnV correlated significantly with the body size (r=0.341), the weight (r=0.272), and the body surface area (r=0.320). After the adjustment to the body size, a threshold value of 1.25cm3 /m was determined for the TnV by using a receiver-operating characteristic curve. This value distinguished moderate to severe from none to mild FMR with a sensitivity of 85% and a specificity of 71%. The intra-observer variability and inter-observer variability were determined to be 0.96 and 0.85, respectively. Automated assessment of TnV has the potential to support the diagnostic evaluation of FMR. Further studies are needed to validate this result, detect additional factors influencing the size of the TnV, and determine further thresholds for any degree of FMR.

Atrial-ventricular function in rheumatic mitral regurgitation using strain imaging

BackgroundChronic mitral regurgitation (MR) historically has been shown to primarily affect left ventricular (LV) function. The impact of increased left atrial (LA) volume in MR on morbidity and mortality has been highlighted recently, yet the LA does not feature as prominently in the current guidelines as the LV. Thus, we aimed to study LA and LV function in chronic rheumatic MR using traditional volumetric parameters and strain imaging.Methods: Seventy-seven patients with isolated moderate or severe chronic rheumatic MR and 40 controls underwent echocardiographic examination. LV and LA function were assessed with conventional echocardiography and 2D strain imaging.Results: LA stiffness index was greater in chronic rheumatic MR than controls (0.95 ± 1.89 vs 0.16 ± 0.13, P = 0.009). LA dysfunction was noted in the reservoir, conduit, and contractile phases compared with controls (P < 0.05). LA peak reservoir strain (πR), LA peak contractile strain, and LV peak systolic strain were decreased in chronic rheumatic MR compared with controls (P < 0.05). Eighty-six percent of patients had decreased LA πR and 58% had depressed LV peak systolic strain. Decreased πR and normal LV peak systolic strain were noted in 42%. Thirteen percent had normal πR and LV peak systolic strain. One patient had normal πR with decreased LV peak systolic strain.Conclusions: In chronic rheumatic MR, there is LA dysfunction in the reservoir, conduit, and contractile phases. In this study, LA dysfunction with or without LV dysfunction was the predominant finding, and thus, LA dysfunction may be an earlier marker of decompensation in chronic rheumatic MR.

Usefulness of Mitral Regurgitant Volume Quantified Using Magnetic Resonance Imaging to Predict Left Ventricular Remodeling After Mitral Valve “Correction”

MRI studies have shown a tight correlation between mitral regurgitant volume and left ventricular end-diastolic volume (LV EDV) in patients with primary chronic mitral regurgitation (MR). They have also shown a tight correlation between regurgitant volume and the decrease in LVEDV following mitral valve surgery. The purpose of this study is to validate an empiric calculation that can be used preoperatively to predict the amount of left ventricular remodeling following mitral valve correction. This is a prospective multicenter study of 63 (61 ± 13 years, male 65%) patients who underwent an MRI before and after mitral valve correction. Pre and postmitral valve correction ventricular volumes and ejection fractions were quantified. The predicted change in LV EDV was empirically calculated as mitral regurgitant volume/left ventricular ejection fraction. The observed change in LV EDV was compared to the predicted change in LV EDV. The LVEDV decreased in 61 (97%) patients following mitral valve correction (237 ± 66 ml vs 164 ± 46 ml, p <0.0001). Correlation between the observed and predicted change in LVEDV was good for the entire cohort (r = 0.77, p <0.0001) and excellent in patients with <10 ml of residual MR (r = 0.87, p <0.0001). This tight correlation was seen in both patients with primary (0.86, p <0.0001) and secondary MR (0.97, p <0.0001) and <10 ml of residual MR. Multivariate predictors of LV remodeling were MR volume, primary MR, and LVESV. In conclusion cardiac MRI volumetric measurements accurately predict LV remodeling following mitral valve correction. This finding supports the notion that MRI accurately quantifies the severity of chronic mitral regurgitation and a cardiac MRI should be strongly considered before mitral valve correction.

Validation of Semiautomated Quantification of Mitral Valve Regurgitation by Three-Dimensional Color Doppler Transesophageal Echocardiography

The aim of this study was to evaluate the accuracy of mitral regurgitation (MR) volume quantified on three-dimensional (3D) color Doppler transesophageal echocardiography (TEE) using new semiautomated software compared with conventional two-dimensional (2D) proximal isovelocity surface area (PISA) transthoracic echocardiography (TTE) and TEE and cardiac magnetic resonance imaging (CMR). Fifty-one patients (mean age, 63±16years; 35 men) prospectively underwent TTE, TEE, and CMR for MR evaluation. Regurgitant volume (RVol) by 3D MR flow quantification was compared with 2D TTE, TEE, and CMR, and the accuracy of evaluation of severe MR by 3D MR flow quantification was compared against guideline criteria by TEE. Twenty-nine patients had severe MR, 16 had moderate MR, and six had mild MR. Three-dimensional MR flow quantification was feasible in all patients, including prolapse (n=37), restriction (n=9), functional MR (n=5), and eccentric or multiple jects (n=41). RVol on 3D MR flow quantification correlated well with RVol on 2D PISA TTE (interclass correlation coefficient [ICC]=0.75, P<.001), quantitatively estimated RVol (ICC=0.74, P<.001), and 2D PISA TEE (ICC=0.79, P<.001). Three-dimensional MR flow quantification agreed better with CMR (ICC=0.86, P<.001) than did RVol on 2D PISA TTE (ICC=0.66, P<.001) and 2D PISA TEE (ICC=0.69, P<.001), with narrower limits of agreement on Bland-Altman analysis. Three-dimensional MR flow quantification had high accuracy for diagnosing severe MR using TEE (area under the curve=0.85, 95% CI 0.74-0.96, P<.001) or CMR (area under the curve=0.95; 95% CI, 0.89-1.00; P<.001) as the criterion. The new software enabled semiautomated 3D MR flow quantification in complex MR with multiple and eccentric jets and showed better agreement with CMR than 2D PISA TTE or TEE, suggesting that this method is more accurate than conventional 2D PISA TTE and TEE.

An Appraisal of the Association of Clinical Outcomes With the Severity of Regurgitant Volume Relative to End-Diastolic Volume in Patients With Secondary Mitral Regurgitation

ImportanceTwo randomized clinical trials of transcatheter edge-to-edge mitral valve repair in patients with secondary mitral regurgitation (the Multicentre Randomized Study of Percutaneous Mitral Valve Repair MitraClip Device in Patients With Severe Secondary Mitral Regurgitation [MITRA-FR] and the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation [COAPT]) report clinical outcome disparities that are largely unexplained. This appraisal sought to provide insight and an explanation for the differences in clinical outcomes (survival and hospitalization rates) in the 2 clinical trials. The mean echocardiogram Doppler results (and derived volume parameters) from each of the 2 clinical trials were compared and examined relative to the clinical outcomes. Special emphasis was placed on the assessment of mitral regurgitation proportionality coefficients that were determined as the ratio of effective regurgitant orifice area (EROA) to end-diastolic volume and the ratio of mitral regurgitant volume to end-diastolic volume.ObservationsIn this analysis of the differences in the clinical outcomes of the MITRA-FR and COAPT clinical trials, the ratio of the EROA to the end-diastolic volume in the COAPT study was found to be twice that of the MITRA-FR study (0.002 cm-1 vs 0.001 cm-1, respectively). The finding of a larger proportional EROA in the COAPT study suggests more severe mitral regurgitation compared with the MITRA-FR study, thereby providing a potential explanation for the different outcomes in the 2 clinical trials. In contrast, the ratio of the mitral regurgitant volume to the end-diastolic volume in the COAPT study was similar to (but slightly lower than) that of the MITRA-FR study (0.15 vs 0.18, respectively), indicating that the proportional mitral regurgitant volume was comparable in the 2 clinical trials. This finding contradicts the conclusions of the EROA analysis.Conclusions and RelevanceThe results of proportionality analyses based on EROA differ from those based on a volume analysis. This disparity casts doubt on the notion that an EROA analysis alone can explain the different results of the 2 randomized clinical trials.

The impact of different geometric assumption of mitral annulus on the assessment of mitral regurgitation volume by Doppler method

BackgroundMitral regurgitation volume (MRvol) by quantitative pulsed Doppler (QPD) method previously recommended suffers from geometric assumption error because of circular geometric assumption of mitral annulus (MA). Therefore, the aim of this study was to evaluate the impact of different geometric assumption of MA on the assessment of MRvol by two-dimensional transthoracic echocardiographic QPD method.MethodsThis study included 88 patients with varying degrees of mitral regurgitation (MR). The MRvol was evaluated by QPD method using circular or ellipse geometric assumption of MA. MRvol derived from effective regurgitant orifice area by real time three-dimensional echocardiography (RT3DE) multiplied by MR velocity-time integral was used as reference method.ResultsAssumption of a circular geometry of MA, QPD-MAA4C and QPD-MAPLAX overestimated the MRvol by a mean difference of 10.4 ml (P < 0.0001) and 22.5 ml (P < 0.0001) compared with RT3DE. Assumption of an ellipse geometry of MA, there was no significant difference of MRvol (mean difference = 1.7 ml, P = 0.0844) between the QPD-MAA4C + A2C and the RT3DE.ConclusionsAssuming that the MA was circular geometry previously recommended, the MRvol by QPD-MAA4C was overestimated compared with the reference method. However, assuming that the MA was ellipse geometry, the MRvol by the QPD-MAA4C + A2C has no significant difference with the reference method.

P1592 Papillary- annular continuum is a dynamic component of obstruction in outflow tract of left ventricle in patients with hypertrophic cardiomyopathy

Abstract The aim to study was to assess Strain of papillary muscles (PM) and their apical displacement with 3D mitral valve (MV) parameters with maximal size of gradient of obstruction in the left ventricle outflow tract (LVOFT) and the volume of mitral regurgitation (MR) in hypertrophic cardiomyopathy (HCMP) patients. Material and methods. 72 HCMP patients (aged of 56.9 ± 11.1 years and gradient in LVOFT 70.83 ± 14.83 mm Hg at rest) were investigated. 3D TEE of MV was performed in all patients with follow up reconstruction. Strain of anterolateral (AL) and posteromedial (PM) papillary muscles (PM) was assess by TTE. Results Strain of both PM was decreased in 45 (62.5)% patients. Positive Strain PM PM were found in 20 (27.8%) patients and AL PM -in 7 (9.7%) patients. Apical displacement of PM PM were registered in 19 (38.0%) pts and ALPM in 6 (12.0%) pts. Apical displacement of both papillary muscles was found in 10 (20.0%) patients. Pts with positive Strain of PM PM had remodeling fibrous ring of MV as compared to patients who had negative Strain of this PM (anteroposterior diameter - 1.97 ± 0.23 sm/m² vs 1.63 ± 0.20sm/m²; p = 0, 01; the perimeter of the ring - 6.92 ± 0.69 sm/m2 vs 6.09 ± 0.93sm/m2; p = 0.02; the area of the ring (3D) - 6.91 ± 1.23sm²/m² vs 5,14 ± 1.31 sm²/m²; p = 0.005). These patients had large areas of the MV leaflets (anterior 4.83 ± 1.03 sm²/m² vs 3.19 ± 0.81 sm² /m² ; p = 0.007; posterior - 4.39 ± 0.42 sm²/m² vs 3.39 ± 1.18 sm²2/m²; p = 0.004), the area of the tenting of leaflets (2.98 ± 1.64 sm²/m² vs 1.24 ± 0.61 sm²/m²; p = 0.04) and the fraction of the tenting (69, 04 ± 24.9% vs 41.27 ± 17.59; p = 0.03). Patients with positive Strain had a greater volume of mitral regurgitation (24.20 ± 11.91 ml vs 14.04 ± 7.58 ml p = 0.004) and the peak gradient in LVOFT was 88.90 ± 37.90 mm Hg vs 66.35 ± 27.00 mm Hg; p = 0.02). Thus, the parameters of 3D MV and strain of PM represent a fixed papillary – annular continuum causing a dynamic component of the obstruction in the LV OT and the volume of mitral regurgitation in patients with HCMP.

P295 Impact of Pre-existing Mitral Regurgitation on the Mid-Term Left Ventricular Mass Regression following Transcatheter Aortic Valve Implantation for Aortic Valve Stenosis

Abstract Background Transcatheter aortic valve implantation (TAVI) results in an immediate and greater aortic pressure gradient improvement in patients with severe aortic valve stenosis (AS), and induces early left ventricular (LV) mass regression, which may be related to favorable effects on the mid to long term outcomes. However, the extent of LV mass regression after unloading of chronic pressure overload is varying, and its determinants are still unknown. Thus, the study aims to identify echocardiographic determinants of LV mass regression following TAVI. Methods We retrospectively screened all TAVI procedures in symptomatic AS from 2017 to 2019, and selected 74 successful TAVI cases that had serial echocardiographic studies both at the baseline and at the mid-term follow-up (4 to 6 months after the procedure). Through the digitalized medical records, clinical and echocardiographic data as well as angiographic grading (0-3) of post-procedure paravalvular leakage (PVL) were obtained. LV mass was calculated by using Cube formula. Thus, the extent of LV mass regression was defined as the differences of left ventricular mas index (LVMI) between at the baseline and at the follow-up (ΔLVMI). Quantification of the baseline mitral valve regurgitant volume was performed by stroke volume method with pulmonic site measurement on the assumption of no pre-existing intra/extra cardiac shunt. Cases with prior mitral valve replacement were excluded. Results At the post-procedure angiogram, only 3 cases had significant PVL (grade 2≤). At the mid-term follow–up, average LVMI decreased significantly from the baseline (165 ± 38 g/m2vs 140 ± 37 mg/ m2, P &amp;lt; 0.0001) and 57 cases (70%) experienced the reduction of LVMI, although average relative wall thickness (2 × posterior wall thickness/left ventricular diastolic dimension) did not change (0.565 ± 0.135 vs 0.586 ± 0.168, P = 0.314). Among the baseline clinical and echocardiographic variables, the baseline peak A wave velocity, E/A ratio, mitral valve regurgitant volume and LVMI revealed simple correlation with ΔLVMI (γ=-0.298, p = 0.0188;γ=0.251, P = 0.0417;γ=0.354, p = 0.0041;γ=0.375, p &amp;lt; 0.0010; respectively), whereas no correlation was observed in angiographic PVL grade. Stepwise multiple regression analysis demonstrated baseline mitral valve regurgitant volume and LVMI as the determinants of ΔLVMI (β=0.344, p = 0.032; β=0.335 P &amp;lt; 0.0001; respectively). Conclusions Pre-existing mitral regurgitation has an impact on the mid–term left ventricular mass regression following TAVI. In severe AS, mitral regurgitation might be functioning as an afterload adjuster, and thus, produces protective effects on LV structure.

P1580 Global regurgitant volume - approaching the critical mass in valvular-driven heart failure

Abstract Aims Recent progress in the diagnosis of functional valve regurgitation forms a coherent perception of severity thresholds by quantitative assessment. However, thresholds focused on either valve in isolation -not accounting for the global hemodynamic burden arising from concomitant functional regurgitation of the mitral and tricuspid valves. We sought to determine whether the global regurgitant volume is associated with adverse cardiac remodeling and mortality. Methods and results This long-term observational study included 414 patients on guideline-directed medical therapy. Baseline global regurgitant load defined as the sum of mitral and tricuspid regurgitant volume was assessed by the proximal flow convergence method. All-cause mortality during five years follow-up served as the primary endpoint. The median global regurgitant load was 30ml (IQR 15-49) with 67% accounting for mitral and 33% accounting for tricuspid regurgitant volume. The global regurgitant load had significant impact on outcome with a crude HR of 1.46 (1.28-1.66; P &amp;lt; 0.001) for a 1-SD increase in global regurgitant volume, results that remained virtually unchanged after bootstrap or clinical confounder-based adjustment (P &amp;lt; 0.001 for adjusted models). Spline curve analysis showed a linearly increasing risk with a threshold of 50ml and sustained increasing risk thereafter. Conclusions The present study demonstrates the detrimental effect of the global regurgitant load in patients with HFrEF. The threshold where heart failure is driven by the valve lesions is a global regurgitant volume of 50ml with continuously increasing risk beyond that threshold. Future studies need to address whether an attempt to reduce the global regurgitant volume can improve outcome. Abstract P1580 Figure 1 - Global RegVol

Quantification of mitral valve regurgitation by 2D and 3D echocardiography compared with cardiac magnetic resonance a systematic review and meta-analysis

By means of systematic literature review and meta-analysis, we compared results of studies examining different echocardiographic methods assessing severity of mitral valve regurgitation volume (MVR) with cardiac magnetic resonance imaging (CMR) as standard reference. A systematic search of electronic databases revealed twenty studies eligible for meta-analysis. Results of 2D- and 3D-trans-thoracic (TTE) and trans-esophageal echocardiographic (TEE) proximal isovelocity surface area (PISA) and volumetric methods were compared with CMR. Mean differences (ml) with 95% limits of agreement (LoA) derived from Bland-Altman tests and correlations coefficients [(R) 95% confidence interval (CI)] were pooled together. Overall 1187 patients [mean age = 59 ± 13years and 678(57%) males] with primary or secondary mild to severe MVR were included. Comparing all echocardiographic methods with CMR showed an overestimation and moderate agreement with difference and 95% LoA of 8.05(- 3.40, 19.49) ml, R = 0.73(95% CI 0.71-0.76) p < 0.001. 3D-PISA followed by 3D-volumetric methods showed the better agreement with an underestimation of - 3.20(- 12.33, 5.92) ml, R = 0.84(95% CI 0.78-0.89) p < 0.001 and overestimation of 3.73(- 9.17, 16.61) ml, R = 0.90(95% CI 0.87, 0.94) p < 0.001, respectively. 2D-volumetric method showed the poorest agreement with difference and 95% LoA of 23.56(- 4.19, 51.31) ml, R = 0.64(95% CI 0.54-0.73) p < 0.001. In patients (n = 280) with severe MVR, 2D technique incorrectly estimated regurgitation volume severity in 106 (38%) compared to 4(14%) patients using 3D technique. Among echocardiographic methods 3D-PISA agreed best with CMR as reference, making 3D-PISA the most reliable method to quantify MVR. CMR can be considered in severe MVR where uncertainties arise and a decision-making prior valve surgery is required. Further powerful studies are needed to assess the accuracy of different echocardiographic methods.

Clinical Situations Associated with Inappropriately Large Regurgitant Volumes in the Assessment of Mitral Regurgitation Severity Using the Proximal Flow Convergence Method in Patients with Chordae Rupture

Regurgitant volume (RVol) calculated using the proximal flow convergence method (proximal isovelocity surface area [PISA]) has been accepted as a key quantitative parameter for the diagnosis of and clinical decision-making with regard to severe mitral regurgitation (MR). However, a recent prospective study showed a significant overestimation of RVol by the echocardiographic PISA method compared with the MR volume measured using magnetic resonance imaging. We aimed to evaluate the frequency of overestimation of RVol by the PISA method and the clinical conditions that require a different quantitative method to correct the overestimation. We retrospectively enrolled 166 consecutive patients with degenerative MR and chordae rupture, in whom RVol was measured using both the PISA and two-dimensional Doppler volumetric methods. The volumetric method was used to measure total stroke volume using the two-dimensional Simpson biplane method, and forward stroke volume was measured using pulsed Doppler tracing at the left ventricular (LV) outflow tract. RVol by the volumetric method was calculated using total stroke volume - forward stroke volume. Severe MR was defined as an RVol >60mL. All patients had severe MR based on RVol by the PISA method, but 68 (41.1%) showed RVol by the volumetric method values of <60mL, resulting in discordant results. The patients with discordant results were characterized by a higher prevalence of female sex, lower body surface area, smaller LV diastolic and systolic dimensions and volumes, smaller left atrial volume, smaller PISA angle, and lower frequency of flail leaflets (39.7% vs 62.2%, P=.004). Multivariate analysis revealed that LV end-diastolic volume (LVEDV) and PISA angle were independent factors, with the best cutoff LVEDV and PISA angle being 173mL and 103°, respectively. During follow-up (median, 3.4years; interquartile range, 2.0-4.8years), mitral valve repair and replacement were performed in 103 and six patients, respectively. The 2-year mitral valve surgery-free survival rate was higher in the discordant group (51.8%±0.06% vs 31.2%±0.05%, P<.001). Even in the patients with documented chordae rupture, the PISA method alone resulted in inappropriate overestimation of MR severity in a significant proportion of patients. Thus, an additive quantitative method is absolutely necessary in patients with a small LVEDV or narrow PISA angle.

P3374Quantification of mitral valve regurgitation volume by 2D and 3D echocardiography compared with cardiac magnetic resonance: a systematic review and meta-analysis

Abstract Background Accurate determination of mitral valve regurgitation (MVR) volume as a measure of left ventricular overload is of great clinical importance for timing of valve repair. The reliability of different echocardiographic methods for assessment of severity of MVR, particularly in severe cases, is currently unclear. Purpose We sought to shed light on this issue by means of a systematic literature review (SLR) and meta-analysis, in which we combined results of all available published studies comparing the different echocardiographic methods with cardiac magnetic resonance (CMR) as standard reference. Methods Electronic databases PubMed and Web of Science were searched for studies examining 2-dimensional (D) and 3D transthoracic and transoesophageal echocardiography (TTE and TEE), using proximal isovelocity surface area (PISA) and volumetric methods and comparing these with CMR. Estimated mean bias with limits of agreements (LoA) derived from Bland-Altman tests and correlations coefficients (R) were pooled together using a weighted inverse variance method. Results Twenty prospective studies were eligible for meta-analysis. Overall 1187 patients with primary or secondary, mild to severe MVR were included. The mean age was 59±13 years and male gender constituted 678 (57%) of patients. Meta-analysis of bias and LoA comparing all echocardiographic methods with CMR showed moderate overestimation and poor agreement with a bias and LoA of 8.24 (−3.55, 20.03) ml, and moderate correlation with R=0.74 (0.70–0.78) p&lt;0.001, Fig 1. 3D-PISA followed by 3D-volumetric methods showed better agreement with an underestimation of −3.20 (−12.33, 5.92) ml, R=0.84 (0.78–0.89) p&lt;0.001 and overestimation of 4.61 (−10.17, 19.39) ml, R=0.90 (0.86, 0.94) p&lt;0.001, respectively. 2D volumetric method showed the poorest agreement with a bias and LoA of 23.56 (−4.19, 51.31) ml, and a moderate correlation with R=0.64 (0.54–0.73), p&lt;0.001. In 172 patients with severe degree of MVR, echocardiographic techniques (2D and 3D) were able to correctly quantify regurgitation severity only in 114 (66%) of cases. Conclusions Echocardiographic methods either under- or overestimate the severity of MVR volume, however, 3D-PISA seems to be more reliable. CMR should be considered particularly in cases of severe MVR where a decision-making prior to valve surgery deems necessary. Powerful randomized studies are needed to further assess the accuracy of different echocardiographic methods in relation to CMR.

P1779Quantitation of severe degenerative mitral regurgitation by echocardiography and CMR with acetate PET for external reference for left ventricular volumes

Abstract Background Quantitative echocardiographic assessment of severity of primary mitral regurgitation (MR) is challenging. CMR is recommended if MR severity cannot be clearly determined, since quantitation of regurgitation as well as of left ventricular (LV) volumes and function is crucial for the indication for surgery especially in asymptomatic patients. Purpose We aimed to compare volumetric measurements obtained from transthoracic echo (TTE) and cardiovascular magnetic resonance (CMR) using ECG-gated [(11)C]acetate PET as reference for assessment of LV volumes. Methods A total of 51 asymptomatic patients with severe primary mitral regurgitation underwent TTE, CMR and PET on the same day. Mitral regurgitant volumes (RVol) were measured by TTE using proximal convergence (PISA) method and by CMR, subtracting aortic forward flow volume from LV stroke volume. LV volumes were measured by TTE, CMR and PET. Results Despite a fair correlation between regurgitant volumes measured by TTE and CMR (r=0.53, p&lt;0.001), PISA method heavily overestimated regurgitant volumes on TTE as compared to CMR (103±60ml vs. 78±35ml, p&lt;0.001). TTE systematically underestimated LV volumes as compared to CMR (see table) despite a good correlation (r=0.81, 0.67 and 0.76 respective for LV EDV, ESV and SV, p&lt;0.001 for all). There was no difference in LV EF between the methods. LV volumes obtained by CMR and PET showed a strong correlation (r=0.92, 0.79 and 0.89 respective for LV EDV, ESV and SV, p&lt;0.001 for all) and agreement (see table). Comparison of TTE, CMR and PET TTE CMR PET PET TTEvs.CMR PET CMRvs.PET F-test LV EDV, ml 145±34 241±57 234±51 &lt;0.001 0.004 &lt;0.001 LV ESV, ml 47±11 76±22 81±23 &lt;0.001 0.067 &lt;0.001L LV SV, ml 99±26 164±38 152±34 &lt;0.001 &lt;0.001 &lt;0.001 LV EF, % 68±5 69±5 65±6 0.236 &lt;0.001 &lt;0.001 Conclusions As compared to CMR, PISA method used by TTE substantially overestimates regurgitant volumes in patients with asymptomatic primary mitral regurgitation. Conversely, LV volumes in spite of good correlation are heavily underestimated by TTE in comparison with CMR. A strong correlation and agreement between LV volumes measured by CMR and PET confirms the accuracy of the former method which is considered as a golden standard for assessment of ventricular function and volumes. Thus, even so-called quantitative echo measures should be understoas essentially semi-quantitative indicators of severity.

P5573Disproportionate functional mitral regurgitation: advancing a conceptual framework from bench to bedside

Abstract Introduction A recently proposed conceptual framework seeks to rearrange the effective regurgitant orifice area (EROA) and regurgitant volume (RegVol) cut-offs according to left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) in functional mitral regurgitation introducing “disproportionate FMR” to describe clinically meaningful FMR. The conceptual framework, however, remains hypothetical. Purpose To test the significance of disproportionate FMR. Methods Data of 291 heart failure patients with reduced ejection fraction (HFrEF) under guideline directed therapy were embedded into this conceptual framework (Figure 1A). The black line represents the relationship when the degree of FMR is proportionate to LVEDV with a regurgitant fraction of (RegFrac) of 50%. The dashed lines represent the degree of uncertainty determined by the imprecision inherent to the measurement of RegFrac defined as 2SD for inter- and intraobserver variability by Bland-Altmann analysis (equals ±6.6%). Cox-regression and Kaplan-Meier analysis were applied to assess the association between FMR proportionality and mortality. Results Median age was 68 years (IQR 61–75), 77% were male. Median LVEF was 25% (IQR 18–33) and LVEDV was 214ml (IQR 165–267). Disproportionate FMR was present in 71 patients (24%) (red dots Figure 1A) with a median EROA of 0.26cm2 (IQR 0.18–0.34) and a median RegVol of 42ml (IQR 28–52), proportionate FMR (yellow dots Figure 1 A) in 81 patients (28%) with a median EROA of 0.12cm2 (IQR 0.09–0.17) and a median RegVol of 18ml (IQR 14–27). During 7-years follow-up, 166 patients died. Disproportionate FMR was associated with excess mortality compared to patients with non-severe FMR (HR 1.97, 95% CI 1.04–0.71, P&lt;0.001), whereas proportionate FMR was not associated with increased long-term mortality (HR 1.04, 95% CI −1.53–0.71, P=0.83, Figure 1B). Figure 1. Panel A and B Conclusion Every fifth patient suffers from disproportionate FMR which conveys a two-fold increased risk of mortality. Disproprtionate FMR corresponds to an EROA of roughly 0.3cm2 and a RegVol of 45ml – the unifying intersection between ESC and ACC/AHA guidelines to define severe FMR. The RegFrac provides a measure proportionated to left ventricular size and function supporting its use to define clinically relevant FMR. However, RegFrac is subject to compound error due to imputation of multiple measurements limiting its use as the leading contender for FMR grading. Regardless of the term used to describe clinically significant FMR, the conceptual framework emphasizes the unmet clinical need for recalibrated cut-offs for FMR severity condensed to an algorithm that combines the strengths of several measurements of FMR severity in an integrated manner.