Regurgitant Volume Research Articles

An orifice shape-based reduced order model of patient-specific mitral valve regurgitation

Mitral valve regurgitation (MR) is one of the most prevalent valvular heart diseases. Its quantitative assessment is challenging but crucial for treatment decisions. Using computational fluid dynamics (CFD), we developed a reduced order model (ROM) describing the relationship between MR flow rates, transvalvular pressure differences, and the size and shape of the regurgitant valve orifice. Due to its low computational cost, this ROM could easily be implemented into clinical workflows to support the assessment of MR. We reconstructed mitral valves of 43 patients from 3D transesophageal echocardiographic images and estimated the 3D anatomic regurgitant orifice areas using a shrink-wrap algorithm. The orifice shapes were quantified with three dimensionless shape parameters. Steady-state CFD simulations in the reconstructed mitral valves were performed to analyse the relationship between the regurgitant orifice geometry and the regurgitant hemodynamics. Based on the results, three ROMs with increasing complexity were defined, all of which revealed very good agreement with CFD results with a mean bias below 3% for the MR flow rate. Classifying orifices into two shape groups and assigning group-specific flow coefficients in the ROM reduced the limit of agreement predicting regurgitant volumes from 9.0 ml to 5.7 ml at a mean regurgitant volume of 57 ml.

Quantification of mitral regurgitation using transthoracic echocardiography and cardiac magnetic resonance imaging

Both Transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) have well-established role in mitral regurgitation (MR) quantification for optimal management strategy. We assessed the correlation between TTE and CMR in the quantification of MR. Participants with isolated MR and echocardiographic mitral regurgitant volume (RVol) ≥ 30 mL/beat were included. A consecutive sample of 30 participants (Mean age 52.7 ± 19.3 years, 50% males) was selected and referred for indirect and direct CMR quantification of mitral RVol. There was a statistically significant strong positive correlation between the echocardiographic and indirect CMR quantification of the mitral RVol (r = 0.753, P < 0.001) and a statistically significant moderate positive correlation between the echocardiographic and direct CMR quantification of the mitral RVol (r = 0.530, P < 0.003). The inter-observer reliability of the MR grade between TTE and CMR showed a statistically significant moderate agreement (κ = 0.502, P = 0.0001) when the observers used the echocardiographic mitral RVol for grading of MR. On the other hand, the inter-observer reliability of the MR grade between TTE and CMR showed a statistically significant faint agreement (κ = 0.251, P = 0.024) when the observers used the echocardiographic regurgitant fraction (RF) for grading of MR. The positive reciprocal relationship between the CMR and the TTE highlights the potential role of the CMR as a concomitant imaging tool for quantification of the mitral RVol and grading of isolated MR, especially with limited or inconclusive TTE studies. This will enhance the management strategy and improve outcomes.

The Results of the Use of Angiotensin Receptor Inhibitors and Neprilisin in Secondary Functional Mitral Regurgitation in Outpatient Practice

Background. Morbidity and mortality in patients with functional mitral regurgitation (FMR) remains high, however, no pharmacological therapy has been proven to be effective.Aimsto study the effect of sacubitrile/valsartan and valsartan on functional mitral regurgitation in chronic heart failure.Methods.This double-blind study randomly assigned sacubitrile/valsartan or valsartan in addition to standard drug therapy for heart failure among 100 patients with heart failure with chronic FMR (secondary to left ventricular (LV) dysfunction). The primary endpoint was a change in the effective area of the regurgitation hole during the 12-month follow-up. Secondary endpoints included changes in the volume of regurgitation, the final systolic volume of the left ventricle, the final diastolic volume of the left ventricle, and the area of incomplete closure of the mitral valves.Results.The decrease in the effective area of the regurgitation hole was significantly more pronounced in the sacubitrile/valsartan group than in the valsartan group (0.070.066against0.030.058sm2; p=0.018)in the treatment efficacy analysis, which included 100patients (100%). The regurgitation volume also significantly decreased in the sacubitrile/valsartan group compared to the valsartan group (mean difference:8.4ml; 95%CI, from 13.2 until 1.9;р=0.21). There were no significant differences between the groups regarding changes in the area ofincomplete closure of the mitral valves and LV volumes, with the exception of the index of the final LV diastolic volume (p=0.07).Conclusion.Among patients with secondary FMR, sacubitril/valsartan reduced MR more than valsartan. Thus, angiotensin receptor inhibitors and neprilysin can be considered for optimal drug treatment of patients with heart failure and FMR.

A comparison of the clinical efficacy of echocardiography and magnetic resonance for chronic aortic regurgitation

Timing surgery in chronic aortic regurgitation (AR) relies mostly on echocardiography. However, cardiac magnetic resonance (CMR) may be more accurate for quantifying regurgitation and left ventricular (LV) remodelling. We aimed to compare the technical and clinical efficacies of echocardiography and CMR to account for the severity of the disease, the degree of LV remodelling, and predict AR-related outcomes. We studied 263 consecutive patients with isolated AR undergoing echocardiography and CMR. After a median follow-up of 33 months, 76 out of 197 initially asymptomatic patients reached the primary endpoint of AR-related events: 6 patients (3%) were admitted for heart failure, and 70 (36%) underwent surgery. Adjusted survival models based on CMR improved the predictions of the primary endpoint based on echocardiography: R2 = 0.37 vs. 0.22, χ2 = 97 vs. 49 (P < 0.0001), and C-index = 0.80 vs. 0.70 (P < 0.001). This resulted in a net classification index of 0.23 (0.00-0.46, P = 0.046) and an integrated discrimination improvement of 0.12 (95% confidence interval 0.08-0.58, P = 0.02). CMR-derived regurgitant fraction (<28, 28-37, or >37%) and LV end-diastolic volume (<83, 183-236, or >236 mL) adequately stratified patients with normal EF. The agreement between techniques for grading AR severity and assessing LV dilatation was poor, and CMR showed better reproducibility. CMR improves the clinical efficacy of ultrasound for predicting outcomes of patients with AR. This is due to its better reproducibility and accuracy for grading the severity of the disease and its impact on the LV. Regurgitant fraction, LV ejection fraction, and end-diastolic volume obtained by CMR most adequately predict AR-related events.

Impact of Myocardial Scar on Prognostic Implication of Secondary Mitral Regurgitation in Heart Failure

ObjectivesThe objective of the present study was to use cardiovascular magnetic resonance (CMR) to examine the natural history of secondary MR severity and the implication of left ventricular (LV) scar on its prognostic significance. BackgroundThere is a need for further understanding of the prognostic implication of secondary mitral regurgitation (MR) given the heterogeneous findings of the 2 recent randomized trials on percutaneous mitral intervention in patients with secondary MR. MethodsPatients with heart failure were enrolled into a prospective observational registry between 2008 and 2019. Outcomes were a composite of all-cause death, heart transplantation, or LV assist device implantation at follow-up. CMR was used to quantify the mitral regurgitation volume and mitral regurgitation fraction (MRF) along with scar burden utilizing late gadolinium enhancement. Patients were categorized into 4 subgroups based on presence and tertiles of scar extent: no scar, limited scar (scar burden 1% to 4%), intermediate scar (scar burden 5% to 20%), and extensive scar (scar burden >20%). ResultsAmong patients (n = 441) included in the study (age 59 ± 14 years, 43% with ischemic etiology), 85 (19%) experienced an adverse event. MRF ≥30% was associated with increased risk of events among the study group (hazard ratio: 1.74; 95% confidence interval: 1.10 to 2.76; p = 0.02). When stratified by presence or absence of scar, MRF ≥30% was associated with events only among patients with scar (hazard ratio: 1.67; 95% confidence interval: 1.02 to 2.76; p = 0.04) but not among patients without scar. On further classification of patients with scar, the prognostic significance of secondary MR was observed primarily among patients with intermediate scar burden. ConclusionsThe natural history of secondary MR is complex, and outcomes are affected by severity of MR and vary depending upon the extent of scar. (DeBakey Cardiovascular Magnetic Resonance Study [DEBAKEY-CMR]; NCT04281823)

First in human experience with an epicardial beating heart device for secondary mitral regurgitation

ObjectiveWe describe a novel, off-pump, epicardial implant that is intended to reshape both the mitral valve annulus and the left ventricle (LV) in those with secondary mitral regurgitation (MR). MethodsFive patients underwent an epicardial implant with the Mitral Touch device (Mitre Medical Corp, Morgan Hill, Calif), during concomitant off-pump coronary artery bypass for secondary MR. The median age was 71.2 years; 4 patients had severe MR and 1 moderate. Patients were followed for 1 year with transthoracic echocardiography and computed tomography. Safety, cardiac remodeling, and MR were assessed by an independent core laboratory. ResultsOne patient died within 30 days from nondevice-related organ failure and the remaining 4 survived through 1-year follow-up. Implant technical success was 100% and took an average of 52 minutes. Paired computed tomography showed mean left ventricular end-systolic volume remodeling at 1 and 12 months of −35% and −31%, respectively. They averaged left atrial end-systolic volume remodeling of −12% and −15% at 1 and 12 months. Right ventricular end-systolic volume changes of −19% and −8% and right atrial end-systolic volume remodeling of −5% and 1%, at the 1- and 12-month time points were noted. Regurgitant volume by transthoracic echocardiography decreased by 46% and 44% and the ejection fraction from 34.6% to 32.1% and 39.5%, at 1 and 12 months, respectively. There were no device-related complications reported to 1 year. ConclusionsThe Epicardial Mitral Touch System for Mitral Regurgitation (ENRAPT-MR) study demonstrates a first-in-man, off-pump, epicardial repair of secondary MR. Procedural safety and geometric correction of the mitral valve apparatus and LV was achieved. Further studies in the United States are underway.

Reliable phase-contrast flow volume magnetic resonance measurements are feasible without adjustment of the velocity encoding parameter.

Purpose: To show that adjustment of velocity encoding (VENC) for phase-contrast (PC) flow volume measurements is not necessary in modern MR scanners with effective background velocity offset corrections. Approach: The independence on VENC was demonstrated theoretically, but also experimentally on dedicated phantoms and on patients with chronic aortic regurgitation ( ) and one healthy volunteer. All PC measurements were performed using a modern MR scanner, where the pre-emphasis circuit but also a subsequent post-processing filter were used for effective correction of background velocity offset errors. Results: The VENC level strongly affected the velocity noise level in the PC images and, hence, the estimated peak flow velocity. However, neither the regurgitant blood flow volume nor the mean flow velocity displayed any clinically relevant dependency on the VENC level. Also, the background velocity offset was shown to be close to zero ( ) for a VENC range of 150 to , adding no significant errors to the PC flow volume measurement. Conclusions: Our study shows that reliable PC flow volume measurements are feasible without adjustment of the VENC parameter. Without the need for VENC adjustments, the scan time can be reduced for the benefit of the patient.

Predictors of right ventricular function and size in patients with hypertrophic cardiomyopathy

We investigated factors associated with right ventricular (RV) function and size in hypertrophic cardiomyopathy (HCM) patients. Two hundred fifty-three consecutive HCM patients and 20 healthy volunteers underwent cardiac magnetic resonance examination. In addition to measuring RV function (ejection fraction—RVEF) and size (end-diastolic volume—RVEDV), each image was inspected for the presence of RV and left ventricular (LV) hypertrophy, and the maximal wall thickness of the left and right ventricles was recorded. HCM patients had higher RVEF and lower RVEDV than healthy volunteers and similar RV mass. The mean RV wall thickness was higher in HCM patients than in controls. LV late gadolinium enhancement (LGE) was present in 89.7% of patients, and RV LGE was present in 3.1% of patients (p < 0.0001). Univariate and multivariable analyses revealed that LVEF, peak LV outflow tract gradient, LV LGE, maximal LV wall thickness, and tricuspid regurgitation (TR) volume by magnetic resonance imaging were positive predictors of RVEF. In addition to TR volume, the only independent predictor of RVEF < 45% was LVEF (odds ratio = 0.80, 95% confidence interval 0.67–0.95). Multivariable analysis revealed that LVEDV and TR volume were positive predictors of RVEDV, whereas negative predictors were RVEF, maximal RV wall thickness, LV LGE, and age. Neither estimated systolic pulmonary artery pressure nor TR grade by echocardiography proved to be predictors of RVEF. There were no differences in either the maximal RV wall thickness or the maximal left ventricular (LV) wall thickness in patients stratified according to NYHA functional class (p = 0.93 and p = 0.15, respectively). There were no differences in mean RV wall thickness in patients categorised based on the number of clinical risk factors for sudden cardiac death (SCD), i.e., non-sustained ventricular tachycardia, family history of SCD, or unexplained syncope (p = 0.79). On the other hand, there was a weak positive association between RV hypertrophy and the estimated probability of SCD at 5 years (rho = 0.16, p = 0.01). RV systolic dysfunction measured as decreased RVEF was uncommon in HCM and was associated with poor LV systolic function. LV also had a significant impact on RV size.

Prognostic validation of partition values for quantitative parameters to grade functional tricuspid regurgitation severity by conventional echocardiography.

Quantitative echocardiography parameters are seldom used to grade tricuspid regurgitation (TR) severity due to relative paucity of validation studies and lack of prognostic data. To assess the relationship between TR severity and the composite endpoint of death and hospitalization for congestive heart failure (CHF); and to identify the threshold values of vena contracta width (VCavg), effective regurgitant orifice area (EROA), regurgitant volume (RegVol), and regurgitant fraction (RegFr) to define low, intermediate, and high-risk TR based on patients' outcome data. A cohort of 296 patients with at least mild TR underwent 2D, 3D, and Doppler echocardiography. We built statistical models (adjusted for age, NYHA class, left ventricular ejection fraction, and pulmonary artery systolic pressure) for VCavg, EROA, RegVol, and RegFr to study their relationships with the hazard of outcome. The tertiles of the derived hazard values defined the threshold values of the quantitative parameters for TR severity grading. During 47-month follow-up, 32 deaths and 72 CHF occurred. Event-free rate was 14%, 48%, and 93% in patients with severe, moderate, and mild TR, respectively. Severe TR was graded as VCavg > 6 mm, EROA > 0.30 cm2, RegVol > 30 mL, and RegF > 45%. This outcome study demonstrates the prognostic value of quantitative parameters of TR severity and provides prognostically meaningful threshold values to grade TR severity in low, intermediate, and high risk.

Myocardial Scar and Mortality in Chronic Aortic Regurgitation.

BackgroundChronic aortic regurgitation (AR) can be associated with myocardial scarring. It is unknown if scarring in AR is linked to poor outcomes and whether aortic valve replacement impacts this association. We investigated the relationship of myocardial scarring to mortality in chronic AR using cardiac magnetic resonance.Methods and ResultsWe enrolled patients with moderate or greater AR between 2009 and 2019 and performed a blinded assessment of left ventricle remodeling, AR severity, and presence and extent of myocardial scarring by late gadolinium enhancement. The primary outcome was all‐cause mortality. We followed 392 patients (median age 62 [interquartile range, 51–71] years), and 78.1% were men, and 25.8% had bicuspid valves. Median aortic valve regurgitant volume was 39 mL (interquartile range, 30–60). Myocardial scar was present in 131 (33.4%) patients. Aortic valve replacement was performed in 165 (49.1%) patients. During follow‐up, up to 10.8 years (median 32.3 months [interquartile range, 9.8–69.5]), 51 patients (13%) died. Presence of myocardial scar (hazard ratio [HR], 3.62; 95% CI, 2.06–6.36; P<0.001), infarction scar (HR, 4.94; 95% CI, 2.58–9.48; P<0.001), and noninfarction scar (HR, 2.75; 95% CI, 1.39–5.44; P<0.004) were associated with mortality. In multivariable analysis, the presence of scar remained independently associated with death (HR, 2.53; 95% CI, 1.15–5.57; P=0.02). Among patients with myocardial scar, aortic valve replacement was independently associated with a lower risk of mortality (HR, 0.34; 95% CI, 0.12–0.97; P=0.03), even after adjustment for confounders.ConclusionsIn aortic regurgitation, myocardial scar is independently associated with a 2.5‐fold increase risk in mortality. Aortic valve replacement was associated with a reduction in risk of mortality in patients with scarring.

Abstract 15253: Significant Discrepancies in Quantification of Regurgitant Volume in Primary Mitral Regurgitation Observed on Multimodality Imaging: Is It Time for Reappraisal?

Introduction: Mitral valve regurgitation volume (RV) can be quantified using proximal isovelocity surface area (PISA) or stroke volume (SV). SV method incorporates mitral annulus (MA) diameter (assumed circular) on 2D transthoracic echo (2D TTE). However, MA area (MAA) can be precisely measured using 3D transesophageal echocardiographic (3DTEE) or computed tomography (CT). Hypothesis: We sought to compare RV obtained using a) PISA b) standard SV using MA diameter on 2D echo and c) modified SV using MAA on 3D TEE and d) MAA on CT. Methods: 37 patients (63±9 years, 81 % men) with severe primary mitral regurgitation (MR) undergoing surgery were prospectively recruited. RV was calculated using a) PISA b) standard SV method using MA diameter on 2D echo (0.785*diameter 2 MV *VTI MV -0.785*d 2 LVOT *VTI LVOT ) c) &amp; d) modified SV methods where MAA (on 3D TEE and CT) were incorporated instead of MA diameter. Results: The mean MAA (cm 2 ) by 2DTTE, 3DTEE &amp; CT were 10.7±3, 10.9 ±3 &amp; 15.9 ±3. Mean RV (cc) by standard SV method, modified SV (3D TEE &amp; CT) &amp; PISA were 294±126, 276±82, 355±127 &amp; 91±51, respectively. Correlations &amp; agreements of SV-based RV are shown in Figure 1. RV was highest using CT-based MAA. The closest agreement was between 2D TTE &amp; CT with a mean error (ME) of -61 cc. There was a large discrepancy in RV derived from PISA vs all SV methods, with a systemic overestimation using SV methods with root mean square errors (RMSE) ranging from 156 to 293 cc Figure 2. Conclusions: In severe MR,calculating RV using SV vs PISA yields vastly different values. The differences are exaggerated using modified SV method incorporating more accurate MAA on 3D TEE or CT. These techniques should not be interchanged to quantify MR.

Abstract 14868: Promises of Transcatheter Tricuspid Valvular Interventions in Patients With Clinically Significant Tricuspid Regurgitation: A Meta-analysis

Introduction: Clinically significant tricuspid regurgitation is common especially in patients with structural heart disease and is independently associated with poor outcomes. Several transcatheter interventions for tricuspid valve repair are under investigation. We aimed to illustrate and summarize the efficacy and safety of these interventions. Methods: We conducted a literature search for relevant clinical registries and trials published until April 2020. We searched PubMed, Scopus, Web of Science, and Cochrane CENTRAL. We performed the analysis of continuous outcomes using the mean difference (MD) while used the risk ratio (RR) for analysis of dichotomous outcomes. We included the following outcomes: Tricuspid annular plane systolic excursion (TAPSE), Vena Contracta (VC), Tricuspid Annulus diameter (TAD), Tricuspid regurgitation volume (TRV), Left ventricular ejection fraction (LVEF), and mortality rates. The random-effects model was used for the analysis of heterogeneous data, while homogeneous data were analyzed under the fixed-effects model. Results: We obtained fifteen clinical registries/trials and included a total of 1329 patients. We found that tricuspid valve interventional devices improved LVEF (MD = 1.46%, 95% CI [0.45, 2.47], p=0.005), led to smaller VC (MD = -4.69, 95% CI [-5.50, -3.88], p=0.005), lower TRV (MD = -11.68, 95% CI [-21.25, -2.11], p=0.02), and smaller TAD (MD = -3.78mm, 95% CI [-5.09, -2.47], p&lt;0.001). No significant difference was noted regarding TAPSE (MD=0.07mm, 95% CI [-0.29, 0.44], p=0.7). Results of the six minutes walking test showed that patients could walk 40 more meters after intervention (MD = 40.64, 95% CI [23.89, 57.40], p&lt;0.001). Pooled mortality rate was 8.2%, stroke 1%, and bleeding 5% during the mean 12 months follow up. Conclusions: Transcatheter tricuspid valve repair devices prove to be effective interventions in decreasing regurgitation and improving functional capacity in patients with clinically significant TR. Mortality (8% during mean 12 months follow up) seems to be related to underlying cardiovascular disease.

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.

Long-term outcome of minimally invasive mitral valve annuloplasty in disproportionate mitral regurgitation

Abstract Background Hypothetical concept of disproportionate secondary mitral regurgitation (SMR) has been recently introduced to facilitate patient's selection for mitral valve intervention. However, real world data validating this concept are unavailable. Purpose To investigate long-term effects of minimally invasive mitral valve annuloplasty (MVA) in patients with disproportionate (dSMR) versus proportionate SMR. Methods The study population consisted of 44 consecutive patients (age 67±9,5 years; 64% males) on guidelines-directed therapy with advanced heart failure (HF), reduced LV ejection fraction (EF) (32±9,7%) and SMR undergoing isolated mini-invasive MVA. Patients with organic mitral regurgitation or concomitant myocardial revascularization were excluded. To assess SMR disproportionality, the PISA-derived effective regurgitant orifice area (EROA) and regurgitant volume (RV) were compared to the estimated EROA and RV by using Gorlin formula and pooled real world data. Results According to EROA, a total of 20 (46%) and 24 (54%) patients, respectively, had dSMR and proportionate SMR (pSMR). According to RV, a total of 17 (39%) had dSMR and 27 (61%) had pSMR. Patients with dSMR showed significantly lower prevalence of male gender and higher prevalence of diabetes mellitus than patients with pSMR (p&amp;lt;0,001). Moreover, we observed smaller LV end-diastolic volume, larger EROA and RV (both p&amp;lt;0,01) and higher LV EF (p=0,02) in the dSMR versus the pSMR group. Other baseline characteristics were similar. During median follow up of 4.39 y (IQR 2,2–9,96y), a total of 25 (56%) patients died from any cause while 21 (47%) individuals were readmitted for worsening HF. Patients with dSMR versus pSMR according to both EROA and RV showed significantly lower rate of HF readmissions (both p&amp;lt;0.05) (Figure 1, 2). In Cox regression analysis combining clinical and imaging parameters, dSMR was the only independent predictor of HF readmissions (HR 0.20, 95% CI 0.07–0.60, p=0.004). In contrast, mortality was similar between dSMR and pSMR (NS) with age as the only independent predictor (HR 1,10; 95% CI 1,03–1,18, p=0,003). Conclusions Minimally invasive MVA is associated with significant reduction of HF readmissions in patients with dSMR versus pSMR while the mortality is similar. This suggests the importance of other parameters, i.e. age and degree of LV remodeling, to guide clinical management in SMR. Funding Acknowledgement Type of funding source: None

Risk stratification on echocardiography and outcome in ischaemic mitral regurgitation

Abstract Background Ischaemic mitral regurgitation (IMR) confers a poor prognosis. Transcatheter intervention may improve survival but benefit is likely to depend on severity of IMR relative to LV remodelling following myocardial infarction (MI). In theory, those with “discordant” IMR (significant regurgitant volume without severe LV dilatation or impairment), are expected to benefit most from mitral intervention. While subcategorization may help to inform treatment, there are no data on post-MI patients in this respect. Purpose To determine the incidence of discordant &amp; concordant IMR categorised on echocardiography post-MI and impact on outcomes. Methods 1000 consecutive patients admitted to our hospital with myocardial infarction who underwent coronary angioplasty were included. Early inpatient TTE was performed by accredited echocardiographers using standard multiparametric quantification. Using TTE parameters, 4 subgroups were identified (figure) according to the degree of MR relative to LV remodelling. Thresholds were based on European guidelines (± 2SD from normal) and median value among survivors for vena contracta (VC): – LVEF: 52% (♂), 54% (♀) – Indexed LV end diastolic volume (LVEDVi): 74ml/m2 (♂), 61ml/m2 (♀) – Effective regurgitant orifice area (EROA) ≥0.2cm2 – Regurgitant volume (RVol) ≥30ml – VC ≥0.5cm Results MR was seen in 294/1000 patients (29.4%) with a severity of mild (76%), moderate (21%) and severe (3%). Concordant and discordant IMR were each seen in 16/294 (5%) of IMR patients post-MI. After a mean follow up of 3.2 years, IMR patients had a 3% rate of heart failure (HF) within 1 year and 19% mortality. Non-survivors had significantly worse IMR (PISA 0.65±0.25cm vs 0.54±0.19cm; p=0.033; VC 0.63±0.25cm vs 0.49±0.18cm; p=0.014), worse LV function (LVEF 44±17% vs 51±13%; p&amp;lt;0.001), larger LV (LVEDVi 67±23ml/m2 vs 60±22ml/m2; p=0.032) and larger indexed LA volume (LAVi) (44±22ml vs 35±15ml; p&amp;lt;0.001). Those with concordant IMR had the worst survival (50%) although almost 1 in 5 of those with discordant MR died within the follow up period (19%). Using multivariable Cox regression, significant predictors of mortality included LVEF (p&amp;lt;0.001; HR 0.96, 0.94–0.98) and LAVi (p&amp;lt;0.001; HR 1.02, 1.01–1.03) but not LVEDVi. Conclusion 1) Significant predictors of mortality in IMR include LA dilatation and decline in LVEF, but not LV dilatation. 2) Although discordant severe IMR is uncommon following MI, mortality if left untreated remains high. Attention should be paid to early selection of this cohort for intervention. Funding Acknowledgement Type of funding source: None

Prognostic differences between atrial functional mitral regurgitation and ventricular functional mitral regurgitation

Abstract Introduction Atrial functional mitral regurgitation (A-FMR) has been under-recognized until recently as a cause of FMR, and the prognostic difference between A-FMR and ventricular FMR (V-FMR) has not been fully elucidated. As there has been different mechanisms of FMR suggested in A-FMR and V-FMR, we hypothesized that prognosis and prognostic predictors of A-FMR may differ from those of V-FMR. Purpose To investigate the prognosis and prognostic predictors of A-FMR in comparison with V-FMR. Methods Among 1312 consecutive patients with grade 3+ (moderate to severe) or 4+ (severe) MR, 378 consecutive FMR patients were identified by excluding patients with degenerative MR, previous cardiac surgery, or concomitant aortic valve disease and/or mitral stenosis. FMR with ejection fraction (EF) &amp;lt;40% or FMR due to regional wall motion abnormalities with leaflet tethering were classified as V-FMR (N=288), and FMR due to left atrial (LA) and/or annular dilatation with preserved or mid-range EF (≥40%) were classified as A-FMR (N=90). All-cause death and heart failure hospitalization were analyzed as cardiovascular (CV) events in this study. Surgical or percutaneous mitral valve intervention without CV events was handled as not reaching an endpoint and these cases were censored. Results A-FMR were significantly older (76 [69–82] vs. 70 [58–77] years), higher rates of female (64 vs. 35%) and atrial fibrillation (88 vs. 42%), and lower B-type natriuretic peptide (BNP) values (169 [101–318] vs. 447 [213–952] pg/ml) compared to V-FMR (all P&amp;lt;0.05). On echocardiography, LV end-diastolic and end-systolic dimensions (52 [48–57] vs. 64 [58–72] mm, 34 [31–37] vs. 55 [48–64] mm), respectively) were smaller, and EF (55 [50–60] vs. 28 [19–35] %) and LA volume (99 [73–137] vs. 73 [57–91] ml/m2) were larger in A-FMR (all P&amp;lt;0.05). Effective regurgitant orifice area (32 [26–40] vs. 31 [24–45] mm2) and regurgitant volume (50±15 vs. 52±16 ml) were similar (both n.s.). During a median follow up of 1407 days, 206 (54%) patients developed CV events. Kaplan-Meier analysis revealed that V-FMR had a significantly higher rates of CV events compared to A-FMR (Figure) with adjusted hazard ratio (HR) of 1.762 [1.168–2.660], P=0.007 after adjusted for variables including age, sex, New York Heart Association functional class, previous heart failure hospitalization, estimated glomerular filtration rate (eGFR) and BNP. Further, stepwise multivariate analysis showed that independent prognostic predictors of A-FMR were LA volume and eGFR, while those for V-FMR were LA volume, age, and LV end-systolic dimension. Conclusions A-FMR had relatively better prognosis compared to V-FMR, and there were different prognostic predictors between A-FMR and V-FMR. Our results suggest that different treatment strategies need to be considered between A-FMR and V-FMR. The Kaplan-Meier life table Funding Acknowledgement Type of funding source: None

Regurgitant fraction as a load-dependent parameter in tricuspid regurgitation quantitation

Abstract Background Regurgitant fraction (RF) is an accepted tool for valvular lesion quantitation in the left heart, while its role in tricuspid regurgitation (TR) is less studied. Purpose The aim of this study was to examine the determinants of RF in TR and its diagnostic utility for TR severity grading in comparison with regurgitant volume (RVol) using guideline recommended integrated algorithm as the reference standard. Methods 114 pts with more-than-mild TR in the absence of pulmonary regurgitation or intracardiac shunt prospectively underwent 2D and 3D transthoracic echocardiography. 3D data sets of the right ventricle (RV) were obtained during breath hold. 3D RVol was calculated through subtracting the right ventricular outflow tract forward stroke volume (SV) from RV SV, where the outflow tract cross-sectional area was derived from single-view measured diameter. 3D RF was calculated by dividing 3D RVol with RV SV. 3D EROA was derived dividing 3D RVol with the velocity-time integral of TR. Results 104 pts were included in the final analysis. 3D RF correlated well with 3D RVol (r=0.80, P&amp;lt;0.0001). Factors encompassing aetiology (organic/functional), heart rate, systolic pulmonary arterial pressure (sPAP), cardiac output, 3D EROA and RV end-diastolic volume index were included in multiple linear regression (R2=0.85), which demonstrated that RF was associated with sPAP (P&amp;lt;0.0001) but not RV end-diastolic volume index (P=0.116). Receiver operator characteristic analysis revealed significant difference in area under the curve between 3D RVol and 3D RF (Z=2.873, P=0.004). Such difference diminished in pts with elevated sPAP (Z=1.226, P=0.220), while remained in those with normal range sPAP (Z=2.897, P=0.004). Conclusions 3D RF is less dependent on volume load but is significantly influenced by pressure load in TR quantitation. The diagnostic power of 3D RF in differentiating severe TR is comparable with 3D RVol in pts with elevated sPAP but is limited in pts with normal range sPAP. Funding Acknowledgement Type of funding source: None

Pressure constrained mitral annular dysfunction determines severity of regurgitation in Barlow's disease – a 3D echocardiographic study

Abstract Background Barlow's disease provides both diagnostic and therapeutic challenges. The impact of systemic blood-pressure on severity of regurgitation is still unclear. Purpose We hypothesized that mitral annulus behaves passively with enlargement during ventricular systole, and secondly, we tested the hypothesis that severity of regurgitation correlates to systemic blood-pressure (BP) of the patient. Methods Ten patients with Barlow's disease were compared with 10 healthy controls. Brachial blood-pressure was measured according to guidelines. Transthoracic 3D echo was obtained from an apical view (38.6±8.2 frames per second). Data was analyzed using a holographic display. We measured commissure width (CW), septallateral length (SL) and mitral annular surface area throughout the cardiac cycle. Aortic flow ejection time was derived from continuous Doppler across the aortic valve. Timing of aortic valve closure was visually assessed by 3D echo. Onset and end of mitral regurgitation was derived from continuous wave Doppler of transmitral flow. Results Systolic BP in controls and patients were 122±5 and 133±12 mmHg, respectively (p&amp;lt;0.05). Enddiastolic volume was 87±7 ml/m2 (controls) and 100±14 ml/m2 (Barlow), p&amp;lt;0.02. Left ventricular EF in controls and patients were 59±5 and 62±5%, respectively, p=NS. Barlow patients had moderate or severe late systolic regurgitation with mean regurgitation volume of 51±18 ml. Annular surface area, CW and SL behaved passively with enlargement during ventricular systole (Figure 1). Peak systolic surface area, CW and SL in healthy controls and Barlow patients were 8.7±0.5 vs 20.7±3.2 cm2 (p&amp;lt;0.001), 30.1±1.5 vs 49.5±4.9 mm (p&amp;lt;0.001) and 30.9±1.5 vs 44.9±3.3 mm (p&amp;lt;0.001). Peak annular surface area and regurgitation volume in patients showed a positive correlation with systolic BP (y = 0.156x − 0.077, r=0.60 and y = 1.136x − 99.7, r=0.80, respectively). Conclusions We have demonstrated pressure constrained mitral annular dysfunction in Barlow's disease, indicating that systemic blood pressure may modify the severity of regurgitation. The study provides novel insights into mechanisms of mitral regurgitation and potential therapeutic actions in the future. Figure 1 Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Grieg Foundation

Disproportionate functional mitral regurgitation: clinical validation of a new conceptual framework

Abstract Background Disproportionate functional mitral regurgitation (FMR) is a novel concept that tries to identify hemodynamically significant FMR by readjusting 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). However, this theoretical concept lacks clinical validation. The aim of this study was to assess the clinical significance of disproportionate FMR. Methods Patients with at least mild FMR and reduced LVEF (&amp;lt;50%) who underwent transthoracic echocardiography between 2010 and 2014 were retrospectively identified in our laboratory database. Optimal medical therapy (including cardiac resynchronization when indicated) for ≥3 months was a prerequisite for inclusion. Hemodynamically significant FMR was defined as regurgitant fraction &amp;gt;50% and the patient-specific theoretical RegVol cut-off was calculated according to the formula presented in Fig. 1a. The difference between the estimated RegVol by the PISA method and the theoretical RegVol cut-off was considered to represent the haemodynamic burden of MR. The primary endpoint was all-cause death. Patients were censured if mitral intervention or heart transplant was undertaken. Survival analysis was used to assess the effect of disproportionate FMR on mortality in 2 subgroups (LVEF &amp;lt;30% and 30–49%). Results A total of 289 patients (median age 69 years [IQR 60–77], 75% male, 53% of ischemic aetiology) were included. More than 90% were on beta-blockers and renin-angiotensin inhibitors, 44% on aldosterone receptor antagonists, and 73% had implanted devices. The median LVEF and LVEDV were 34% (IQR 27–41) and 170mL (IQR 128–220), respectively. Median EROA was 10mm2 (IQR 3–21) and RegVol was 15 mL (IQR 4–30). RegVol distribution across the cohort was: &amp;lt;10mL: 41%; 10–20mL: 18%; 20–30mL: 15% and &amp;gt;30mL: 26%. Disproportionate FMR was present in 83 patients (29%). These patients had significantly higher SPAP values (41mmHg [IQR 33–50] vs. 33mmHg [IQR 29–40]; p&amp;lt;0.001). During a median follow-up of 44 months (IQR 19–73), 106 patients died. In the LVEF &amp;lt;30% subgroup, age (HR 1.05 per year [1.02–1.08]; p&amp;lt;0.001), LVEF (HR 0.94 per 1% [0.89–0.99]; p=0.042) and TAPSE (HR 0.92 per mm [0.86–0.99]; p=0.030) were independent predictors of mortality. In the LVEF 30–49% subgroup, age (HR 1.05 per year [1.02–1.08]; p=0.003), LVEF (HR 0.94 per 1% [0.89–0.99]; p=0.020) and disproportionate FMR (HR 1.02 per mL [1.01–1.03]; p=0.01) were independently associated with increased mortality. Conclusions Disproportionate FMR proved to be an important independent predictor of mortality in patients with LVEF between 30–49%. These findings were not replicated in those with LVEF&amp;lt;30%, where the degree of biventricular dysfunction seems to outweigh all other echocardiographic parameters, leaving FMR as a bystander. Figure 1 Funding Acknowledgement Type of funding source: None

Left ventricular myocardial work in patients with secondary mitral regurgitation

Abstract Background Assessment of left ventricular (LV) function in patients with secondary mitral regurgitation (SMR) remains challenging because LV ejection fraction (LVEF) reflects changes in LV volume without taking into account the direction of the blood flow. LV global longitudinal strain better reflects active LV myocardial deformation but does not incorporate afterload. LV myocardial work derived from pressure-strain loops integrates speckle tracking echocardiography with non-invasive blood pressure measurement. Purpose To evaluate LV myocardial work components to better characterize LV function in patients with SMR. Methods 378 patients (72% men, median age 68 [range 60 to 74 years]) with various grades of SMR were retrospectively analysed. LV myocardial constructive work, wasted work and work efficiency were measured with speckle tracking echocardiography. Results 145 patients had mild SMR, 130 moderate SMR and 103 severe SMR. Patients with severe SMR had larger LV volumes, lower LVEF and more impaired LV GLS (Table 1). While LV constructive work was more impaired in patients with severe SMR, wasted work was lower as compared to mild SMR (Table 1). Consequently, patients with severe SMR had better myocardial work efficiency than patients with mild MR. This could reflect, the regurgitant volume which is pumped into a low pressure chamber (the left atrium) resulting in less myocardial wasted work and preservation of myocardial efficiency. Conclusion In patients with severe SMR, LVEF, LV GLS and myocardial constructive work are more impaired when compared to mild SMR. However, myocardial wasted work is lower, resulting in higher better LV myocardial work efficiency. Funding Acknowledgement Type of funding source: None