Significant Primary Mitral Regurgitation Research Articles

The effect of exercise on RV-PC coupling in asymptomatic patients with significant primary mitral regurgitation

Abstract Background Right ventricular–pulmonary circulation (RV-PC coupling) serves as an index to evaluate RV function in relation to underlying RV afterload. Although impaired RV-PC coupling has been proposed as a predictor of adverse outcomes in heart failure (HF) patients with secondary mitral regurgitation (MR), there is limited data available for patients with primary MR. Purpose The objective of this study was to assess and compare alterations in RV-PC coupling during exercise with bicycle stress echocardiography in individuals with asymptomatic moderate to severe primary MR (MR group) and normal subjects (Control group). Μethods All patients and controls underwent stress echocardiography with a supine bicycle. RV systolic function was evaluated with TAPSE and S’. The non-invasively measured RV-PC coupling was evaluated by indexing TAPSE and S’ to right ventricular systolic pressure (RVSP) during baseline echocardiogram and peak workload stages of bicycle SE. Results Among the 48 patients in the MR group (mean age 53.5±15.16 years, 58.3% female), 39 patients had moderate MR(81.3%), 5 patients had moderate-to-severe MR(10.4%), and 4 patients had severe MR(8.3%). The duration of stress echocardiogram was significantly shorter in the MR group compared to control group (8.11±2.39 min vs 10.5±1.05 min, respectively; p<.001). Left Ventricular Ejection Fraction (LVEF) was within normal limits in both groups {70.7±11.9 % vs 72.6±12.1 %(p=NS} and the dimensions of left ventricular cavity (end-diastolic and end-systolic diameters) were significantly larger in the MR group compared to control group (49.25±5.21 mm vs 45.6±4.08mm (p .016) and 31.81±4.27mm vs 29.07±4.21mm (p .033) respectively}. TAPSE and RVSP increased from baseline to peak dose [23.48 ±3.05mm vs 29.94±3.48mm (p < .001), 8.54±4.56mmHg vs 43.79±5.27mmHg (p < .001), respectively]. There were no significant differences in TAPSE/RVSP and S’/RVSP between the two groups at rest. However, a significantly steady decrease was observed from baseline to peak dose (0.84±0.16 mm/mmHg vs 0.72±0.19mm/mmHg (p <.001) and 0.52±0.11 cm/sec/mmHg vs 0.50±0.15 cm/sec/mmHg (p .004), respectively). Conversely, these parameters did not exhibit a significant decrease in the control group. Finally, there was no significant correlation observed between the changes in the index TAPSE/RVSP , ratio E/E’ and systolic blood pressure. Conclusions RV-PC coupling decreases during exercise in asymptomatic patients with moderate to severe MR, independently of left ventricular dynamic changes. In contrast , there is no significant change in RV-PC coupling observed in the control group. Therefore, future studies should aim to evaluate the incremental role of this novel index not only in the assessment and evaluation of patients with MR but also as a potential prognostic marker.TAPSE/RVSP GraphTable of echocardiographic measurements

Exercise pulmonary hypertension by the mPAP/CO slope in primary mitral regurgitation.

Exercise-induced pulmonary hypertension (PH), defined by a mean pulmonary arterial pressure over cardiac output (mPAP/CO) slope >3 mmHg/L/min, has important diagnostic and prognostic implications. The aim of this study is to investigate the value of the mPAP/CO slope in patients with more than moderate primary mitral regurgitation (MR) with preserved ejection fraction and no or discordant symptoms. A total of 128 consecutive patients were evaluated with exercise echocardiography and cardiopulmonary testing. Clinical outcome was defined as the composite of mitral valve intervention, new-onset atrial fibrillation, cardiovascular hospitalization, and all-cause mortality. The mean age was 63 years, 61% were male, and the mean LVEF was 66 ± 6%. The mPAP/CO slope correlated with peak VO2 (r = -0.52, P < 0.001), while the peak systolic pulmonary artery pressure (sPAP) did not (r = -0.06, P = 0.584). Forty-six per cent (n = 59) had peak exercise sPAP ≥60 mmHg, and 37% (n = 47) had mPAP/CO slope >3 mmHg/L/min. Event-free survival was 55% at 1 year and 46% at 2 years, with reduced survival in patients with mPAP/CO slope >3 mmHg/L/min (hazard ratio, 4.9; 95% confidence interval, 2.9-8.2; P < 0.001). In 53 cases (41%), mPAP/CO slope and peak sPAP were discordant: patients with slope >3 mmHg/L/mmHg and sPAP <60 mmHg (n = 21) had worse outcome vs. peak sPAP ≥60 mmHg and normal slope (n = 32, log-rank P = 0.003). The mPAP/CO slope improved predictive models for outcome, incremental to resting and exercise sPAP, and peak VO2. Exercise PH defined by the mPAP/CO slope >3 mmHg/L/min is associated with decreased exercise capacity and a higher risk of adverse events in significant primary MR and no or discordant symptoms. The slope provides a greater prognostic value than single sPAP measures and peak VO2.

Clinical significance of myocardial contraction fraction in significant primary mitral regurgitation

BackgroundThe optimal timing for mitral valve (MV) surgery in asymptomatic patients with primary mitral regurgitation (MR) remains a matter of debate. Myocardial contraction fraction (MCF) − the ratio of the left ventricular (LV) stroke volume to that of the myocardial volume − is a volumetric measure of LV myocardial shortening independent of size or geometry. AimTo assess the relationship between MCF and outcome in patients with significant chronic primary MR due to prolapse managed in contemporary practice. MethodsClinical, Doppler-echocardiographic and outcome data prospectively collected in 174 patients (mean age 62 years, 27% women) with significant primary MR and no or mild symptoms were analysed. The impact of MCF< or ≥30% on cardiac events (cardiovascular death, acute heart failure or MV surgery) was studied. ResultsDuring an estimated median follow-up of 49 (22–77) months, cardiac events occurred in 115 (66%) patients. The 4-year estimates of survival free from cardiac events were 21±5% for patients with MCF <30% and 40±6% for those with ≥30% (P<0.001). MCF <30% was associated with a considerable increased risk of cardiac events after adjustment for established clinical risk factors, MR severity and current recommended class I triggers for MV surgery (adjusted hazard ratio: 2.33, 95% confidence interval: 1.51−3.58; P<0.001). Moreover, MCF<30% improved the predictive performance of models, with better global fit, reclassification and discrimination. ConclusionsMCF<30% is strongly associated with occurrence of cardiac events in patients with significant primary MR due to prolapse. Further studies are needed to assess the direct impact of MCF on patient management and outcomes.

Comparison of Mitral Regurgitant Volume Assessment between Proximal Flow Convergence and Volumetric Methods in Patients with Significant Primary Mitral Regurgitation: An Echocardiographic and Cardiac Magnetic Resonance Imaging Study

Discrepancies have been observed between transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR) severity grading in primary mitral regurgitation (MR). We sought to compare mitral regurgitant volume (RVol) determined by the TTE proximal flow convergence (proximal isovelocity surface area [PISA]) method and by volumetric methods (TTE and CMR) and to study the relationship between left ventricle (LV) size and RVol obtained by either the PISA or volumetric methods. Two centers prospectively recruited 188 patients with at least moderate to severe primary MR due to prolapse in sinus rhythm who underwent TTE and CMR examinations. Regurgitant volume was estimated by either PISA (PISA-RVol) or volumetric methods (LV total stroke volume-systolic aortic forward outflow volume) using either CMR (CMR-RVol) or TTE (TTE-RVol). The PISA-RVol was weakly correlated with CMR-RVol and TTE-RVol (r=0.29 and 0.30, respectively; P<.001 for both). On multivariable analysis, smaller CMR-left ventricular end-diastolic volume (LVEDV) and absence of mitral annular disjunction independently correlated with increased magnitude of RVol difference between PISA and volumetric methods. While PISA-RVol and LVEDV were unrelated, CMR-RVol and TTE-RVol moderately correlated with LVEDV (r=0.66 and 0.68, respectively; P<.001 for both). In contrast, LVEDV and regurgitant fraction (RVol/LVtotal stroke volume), assessed with either TTE or CMR, were poorly correlated (r=0.17, P=.02; and r=0.12, P=.10, respectively). Mitral RVol values estimated by PISA and volumetric methods are not directly comparable. The expected proportional relationship between volumetric RVol and LV size, which was not observed with PISA-RVol, suggests that PISA-RVol would be inaccurate. Given that RVol assessed with volumetric methods depends on LV size, determination of a unique RVol threshold for severe MR is challenging. In contrast to RVol, calculating regurgitant fraction by volumetric methods allows the quantification of MR severity independently from LV size.

Assessment of novel echocardiographic indices of myocardial function in patients with significant primary mitral regurgitation

Abstract Funding Acknowledgements Type of funding sources: None. INTRODUCTION Assessment of left ventricular (LV) function in primary mitral regurgitation remains challenging due to ejection fraction preservation, even in late stages of the disease. Global longitudinal strain (GLS) remains a valuable tool for the assessment of systolic function which is affected, like ejection fraction, by loading conditions. Lately, novel methods, such as myocardial work estimated by echocardiography, have been developed in assessment of LV systolic function, along with left atrial strain in assessment of diastolic function. Early identification of systolic or diastolic dysfunction in primary mitral regurgitation is crucial for further management of these patients. PURPOSE In this study we assessed several indices of LV systolic and diastolic function, such as myocardial work, global longitudinal strain and left atrial strain, in patients with significant primary mitral regurgitation, in order to evaluate early myocardial dysfunction. METHODS We retrospectively assessed echocardiograms of 64 patients, referred to an echocardiography laboratory of a tertiary hospital between 2019 and 2021 with the diagnosis of significant primary MR. Measurements included several echocardiographic indices of LV anatomy and function, such as left atrial volume indexed (LAVi), left atrial strain, global longitudinal strain (GLS), pulmonary hypertension and global myocardial work. Finally we correlated various indices of systolic and diastolic function with severity of mitral regurgitation. RESULTS We analyzed echocardiograms of 64 patients (50 men, mean age 60 ± 13,8) with at least moderate organic MR, 75,8% of which had severe MR, and normal ejection fraction (mean EF 63%±4,9). We identified negative correlation between left atrial strain (reservoir) and pulmonary hypertension measurements (correlation coefficient -358, p &amp;lt; 0,05) in patients with at least moderate MR. However, we were not able to find any statistically significant differences in GLS (21,98 vs 22,26) or myocardial work, even though we noticed a difference in myocardial work between patients with moderate and severe MR (Global Work Index 2302mmHg% vs 2262mmHg% with normal values 2209 ± 307mmHg% in STAAB cohort, Global Constructed Work 2540mmHg% vs 2327mmHg%, Global Waste Work 136,89mmHg% vs 136,43mmHg%, Global Work Efficiency 94,22% vs 93,76%). CONCLUSIONS These data suggest that an early assessment of indices of diastolic function, such as left atrial strain linked to pulmonary hypertension, can guide to a more effective evaluation of patients with severe MR and normal systolic function. Additionally, novel indices of LV function less load-dependent, such as myocardial work, are promising tools in the assessment of left ventricle and early recognition of myocardial dysfunction in patients with severe organic MR, but more prospective studies are needed. Abstract Figure. Abstract Figure.

Comparison of mitral regurgitant volume assessment between proximal flow convergence and volumetric methods in patients with significant primary mitral regurgitation

Abstract Funding Acknowledgements Type of funding sources: None. Background. Discrepancies have been observed between transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (MRI) severity grading in primary mitral regurgitation (MR). Purpose. To compare mitral regurgitant volume (RV) obtained by the proximal flow convergence method (PISA) method by TTE and by volumetric methods (TTE and MRI), and study the relationship between LV size and RV obtained by either the PISA or volumetric methods. Methods and results. 188 patients from 2 heart valve clinics with at least moderate-to-severe primary MR due to prolapse in sinus rhythm who underwent evaluation with TTE and MRI were included. RV was estimated by either PISA or volumetric methods (Left ventricular [LV] stroke volume minus systolic aortic outflow volume)) by either MRI (MRI-RV) or TTE (TTE-RV)). PISA-RV and either MRI-RV or TTE-RV weakly correlated (r = 0.29 and 0.30,p &amp;lt; 0.001). On multivariable analysis, LV end-diastolic volume (LVEDV) and bileaflet prolapse independently correlated with the magnitude of the difference between PISA and volumetric methods. While PISA-RV and LVEDV were unrelated, MRI-RV and TTE-RV strongly correlated with LVEDV (r = 0.66 and 0.68,p &amp;lt; 0.001). In contrast, LVEDV and regurgitant fraction (RF = RV/LVEDV) either with TTE or MRI were poorly related (r = 0.17,p = 0.02 and r = 0.12,p = 0.10). Conclusion. RV estimated by the PISA and volumetric methods are not comparable. The expected proportional relationship between volumetric RV and LV size, which is not observed with PISA-RV suggests the inaccuracy of PISA-RV. Given that RV by volumetric methods depends on LV size, determination of a unique RV threshold for severe MR is challenging. Calculation of RF may overcome this limitation. Abstract Figure. RV assessed by PISA or volumetric method Abstract Figure. Illustrative example

Long-Term Impact of Preventive Tricuspid Valve Annuloplasty on Right Ventricular Remodeling

In patients with primary mitral regurgitation (MR), concomitant tricuspid valve (TV) annuloplasty at the time of left-sided valve surgery is indicated in case of a dilated TV annulus ≥40mm independent of the presence or severity of tricuspid regurgitation (TR). However, the long-term impact on right ventricular (RV) adverse remodeling is less well established and the benefit of preventive TV annuloplasty remains controversial. The aim of the study was to assess differences in long-term RV adverse remodeling and the development of significant TR in those patients. In total, 98 patients (mean age 65 ± 11years, 85% men) with significant primary MR and TV annulus dilatation ≥40mm without significant TR who underwent mitral valve (MV) repair with or without concomitant TV annuloplasty were included. Of the 98 patients, 28 patients underwent isolated MV repair without TV annuloplasty and 70 patients received concomitant TV annuloplasty at the time of MV surgery. The RV basal diameter (p=0.03), RV long-axis diameter (p=0.04), RV end-diastolic area (p <0.01), and RV end-systolic area (p=0.03) showed less adverse remodeling at follow-up in patients with concomitant TV annuloplasty compared with patients without TV annuloplasty. Additionally, 4 patients (14%) in the subgroup without TV annuloplasty developed significant TR during follow-up in contrast to zero patients in the subgroup with TV annuloplasty (p=0.001). In conclusion, concomitant preventive TV annuloplasty during MV surgery in patients with primary MR, no significant TR and a tricuspid annulus (≥40mm) prevented RV adverse remodeling and the development of significant TR at long-term follow-up.

Global constructive myocardial work predicts left ventricular disfunction onset beyond longitudinal strain in patients with significant primary mitral regurgitation

Abstract Accurate surgical timing for significant primary mitral regurgitation (PMR) still remains an issue despite of several ways of left ventricular (LV) hidden disfunction detection, including LV global longitudinal strain (GLS). Since novel modalities such as myocardial work (MW) or area strain (AS) are currently available we assumed that they might predict surgical timing beyond known parameters. Methods 58 patients (31 female) 63±8 years, asymptomatic and with pulmonary systolic pressure (PSP) ≤45 mmHg on exercise echo test (ET), with PMR, in sinus rhythm, with ejection fraction (EF) ≥65% and GLS &amp;lt;−19.5% were enrolled into the study along with 23 healthy subjects matched by age and sex and followed up for 1 year. Comprehensive echocardiography (EchoCG) was performed with offline analysis including MW and AS by one experienced specialist. GW index (GWI) was obtained from pressure-strain loops derived from speckle tracking analysis multiplied by brachial systolic blood pressure.Global constructive work (GCW) as the sum of positive work due to myocardial shortening during systole and negative work due to lengthening during isovolumic relaxation, global wasted work (GWW) aa energy loss by myocardial lengthening in systole and shortening in isovolumic relaxation, and GW efficiency (GWE) as the percentage ratio of constructive work to the sum of constructive work and wasted work were obtained by the dedicated software. Results 13 (22%) patients with PMR became symptomatic or increase PSP &amp;gt;50 mmHg on ET in 1 year follow up. EF, GLS, AS and GWI did not differ between symptomatic patients and those who remained asymptomatic during follow up, however these patients had significantly lower values of GCW, and higher values of GWW (EF 68.3±6.1% vs 69.2±6.5%, p=NS; GLS –22.4±2.3% vs 23.1±3.2%, p=NS, GWI 2452±161 mmHg% vs 2479±147 mmHg%, p=NS; GCW 1875±119 mmHg% vs 2321±124 mmHg%, p&amp;lt;0.01; GWW 118±9 mmHg% vs 88±7 mmHg%, p&amp;lt;0.03; GWE 93±8% vs 96±9%, p=NS; AS −32.5±5.4% vs −34.3±6.1%, p=NS;). Patients with subsequent symptoms development had significantly lower values of GCW and higher values of GWW. Among all parameters GCW was the predictor of MR clinical course worsening (AUC 0.769). Conclusion MR GCW is able to predict clinical course of patients with PMR beyond known conventional parameters. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): City Hall resources

Incremental value of P-wave indices for predicting left atrial dysfunction in patients with primary mitral regurgitation using speckle tracking echocardiography.

The correlation of P wave indices on surface ECG and phasic LA dysfunction in patients with significant primary mitral regurgitation (MR) due to the adverse LA adaptive structural and functional changes needs to be more studied. This study aims to investigate the diagnostic value of P wave indices to predict LA function assessed both by volumetric analysis using 3-dimensional (3D)echocardiography, and by strain analysis using speckle tracking echocardiography. (STE). The study included 107 subjects, we measured maximum P-duration (Pmax), P dispersion (PD), and V1 negative terminal force (V1-NTF) (negative duration x negative amplitude) on surface ECG. Both Basic and Dynamic LA volumes (LAV) during reservoir, conduit, and contractile phases were measured. The global LA strain and strain rate parameters were calculated By STE. LA ejection fraction (LAEF) and ejection force were also calculated.V1-NTF showed a significant positive correlation while P-max a significant negative correlation with global peak atrial longitudinal strain (GPALS) (r = 0.75; P < 0.001 and r = - 0.72; P < 0.001 respectively). Using ROC curve analysis, Pmax > 110ms, 1-NTF ≥ 4ms.mV and P notching > 40ms had a sensitivity of 90%, 95% and 50% and a specificity of 87.4%, 94.3% and 100% respectively in predicting GPALS ≤ 30%. P notching > 40ms was associated with severe LA dysfunction. ECG P wave indices represent a simple bedside tool that could have an incremental role in predicting LA dysfunction as well as size in patients with significant primary MR.

Parameters associated with ventricular arrhythmias in mitral valve prolapse with significant regurgitation

ObjectiveMitral valve prolapse (MVP) has been associated with ventricular arrhythmias (VA), but little is known about VA in patients with significant primary mitral regurgitation (MR). Our aim was to describe...

P1425 Association between severity of mitral regurgitation and right ventricular function in patients with moderate to severe mitral regurgitation assessed by invasive hemodynamics measurements

Abstract Funding Acknowledgements - Background Primary mitral regurgitation (MR) will cause volume overload to the left ventricle (LV) but due to systolic reguritant flow the pulmonary circulation will be affected often leading to post-capillary pulmonary hypertension and thus increased afterload to the right heart. As a consequence right ventricular (RV) dysfunction may be a consequence of MR. Purpose To assess the association between RV function assessed with cardiac magnetic resonance imaging (CMRI) and hemodynamics at rest and during exercise in ambulatory patients with primary mitral regurgitation (MR). Methods In an observational study, patients with significant primary MR with effective regurgitant orifice ≥0.30 cm2 and LV ejection fraction &amp;gt;60% were examined with right heart catheterization during rest and exercise and CMRI at rest. Patients were examined in semi-supine position (30 degree). From right heart catheterization pulmonary artery systolic pressure (PAPs) was measured, where RV stroke work index (RVSWI = 0.0136*(mean pulmonary artery pressure – right atrial pressure *stroke volume index) and pulmonary artery compliance (PAC= stroke volume / (PAPsystolic – PAPdiastolic)) was calculated. Patients were dichotomized according to effective regurgitant orifice (ERO) (≤0.4 cm2). Results The two groups (total n = 46) have same baseline characters with no significant differences. In both groups resting RVEF was normal and no difference in RV stroke volume was seen between the groups at rest or with exercise. However RVSWi was significantly higher in patients with ERO &amp;gt; 0.4, (rest p = 0.0039, exercise p = 0.01), Figure. The increase in RVSWi was driven by increased sPAP and where significantly in ERO &amp;gt; 0.4 at rest at during exercise (rest p = 0.00027, exercise p = 0.0352). At rest PAC was significantly higher in ERO above 0.4, but during exercise no differences was found in the two groups. RVEF at rest measured by CMRI showed no correlation with RVSWi in the two groups (r = 0.11, p = 0.45) Conclusion In ambulatory patients with mitral regurgitation above 0.4 cm2, RVSW is associated with an increased right ventricle workload and contractility at rest and during exercise which especially is driven by increased post capillary pressure whereas pulmonary arterial compliance only is mildly affected. Abstract P1425 Figure. Ventricle function at rest/exercise

Cardiac remodelling and haemodynamic characteristics in primary mitral valve regurgitation

ObjectiveTo assess the association between cardiac morphology and function assessed with cardiac MRI (CMRI) and haemodynamics at rest and during exercise in patients with primary mitral regurgitation (MR).MethodsIn an observational...

Exercise capacity in asymptomatic patients with significant primary mitral regurgitation: independent effect of global longitudinal left ventricular strain.

Despite preserved left ventricular ejection fraction (LVEF), patients with significant primary mitral regurgitation (MR) often have reduced exercise capacity. In asymptomatic patients with ≥3+ primary MR undergoing rest-stress echocardiography (RSE), we sought to evaluate the incremental impact of left ventricular global longitudinal strain (LV-GLS) on exercise capacity. A total of 660 asymptomatic patients with ≥3+ primary MR, non-dilated LV and LVEF ≥60% (mean age, 57±14 years, 66% men, body mass index or BMI 25±4 kg/m2) who underwent RSE at our center between 2001 and 2013 were included. Standard RSE data were obtained. Average resting LV-GLS was measured using Velocity Vector Imaging. Mean mitral effective regurgitant orifice, resting right ventricular systolic pressure (RVSP) and LV-GLS were 0.45±0.2 cm2, 31±12 mmHg and -21.7%±2%, respectively; 28% had flail mitral leaflet. Mean metabolic equivalents (METs) and post-stress RVSP were 9.9±3, and 46±15 mmHg; 28% achieved <100% age-gender predicted METs. No patient had ischemia or significant arrhythmias. On logistic regression, resting LV-GLS [odds ratio (OR), 1.40, 95% confidence interval (CI): 1.21-1.55, BMI (OR, 1.11, 95% CI: 1.06-1.17)] and resting RVSP 1.22 (1.02-1.49) were independent predictors of exercise capacity. Area under the curve for association between 100% age-gender predicted METs and various factors were as follows: (I) BMI (0.60, 95% CI: 0.55-0.65, P<0.001); (II) resting RVSP (0.57, 95% CI: 0.52-0.62, P=0.006) and LV-GLS (0.66, 95% CI: 0.61-0.70, P<0.001). In asymptomatic patients with ≥3+ primary MR, non-dilated LV and preserved LVEF, LV-GLS is independently associated with exercise capacity, beyond known predictors.

Layer-specific deformation analysis in severe aortic valve stenosis, primary mitral valve regurgitation, and healthy individuals validated against invasive hemodynamic measurements of heart function.

Speckle tracking echocardiography is considered valuable in assessing left ventricular (LV) function. The method has been refined to assess deformation in different myocardial layers, but the effect of volume vs pressure overload on this pattern is unknown. The aim was to test whether layer-specific myocardial strain (LSS) obtained by speckle tracking echocardiography exhibits different patterns in conditions with different loading conditions. Forty patients with asymptomatic severe aortic stenosis (AS) (AVA 0.81±0.15cm2 , LV ejection fraction [LVEF] 66%±7%), 43 patients with asymptomatic or mildly symptomatic significant primary mitral regurgitation (MR) (effective regurgitant orifice (ERO) 0.51 (IQR 0.37-0.67)cm2 , LVEF 70%±7%), and 23 healthy individuals (LVEF 65%±6%) were enrolled. Echocardiography and right heart catheterization were performed in all patients. In MR, strain values in each myocardial layer (endocardial/global longitudinal strain (GLS)/epicardial) were higher (25.0%±3.4%/21.6%±2.9%/18.8%±2.6%) compared to healthy individuals (22.6%±3.2%/19.6%±2.9%/17.1%±2.6%) and AS (20.5%±2.8%/17.7%±2.5%/14.0%±5.6%), P<.001. All 3 groups exhibited a similar LSS pattern with highest values in the endocardial and lowest values in the epicardial layer. The epicardial-endocardial strain ratio was lower in AS (0.72±0.04) than in MR (0.75±0.04, P=.04). Global longitudinal strain (GLS) correlated significantly with LV wall stress (r=.39, P=.0003) but not with LV stroke work or contractility. Layer-specific myocardial strain (LSS) patterns differed in patients with severe AS, significant MR, and healthy individuals with highest values in MR. Strain irrespective of layer assessed was associated with LV wall stress but seemed less related to contractility and unrelated to stroke work in the setting of normal LVEF.

Synergistic Utility of Brain Natriuretic Peptide and Left Ventricular Global Longitudinal Strain in Asymptomatic Patients With Significant Primary Mitral Regurgitation and Preserved Systolic Function Undergoing Mitral Valve Surgery.

In asymptomatic patients with ≥3+ mitral regurgitation and preserved left ventricular (LV) ejection fraction who underwent mitral valve surgery, we sought to discover whether baseline LV global longitudinal strain (LV-GLS) and brain natriuretic peptide provided incremental prognostic utility. Four hundred and forty-eight asymptomatic patients (61±12 years and 69% men) with ≥3+ primary mitral regurgitation and preserved left ventricular ejection fraction, who underwent mitral valve surgery (92% repair) at our center between 2005 and 2008, were studied. Baseline clinical and echocardiographic data (including LV-GLS using Velocity Vector Imaging, Siemens, PA) were recorded. The Society of Thoracic Surgeons score was calculated. The primary outcome was death. Mean Society of Thoracic Surgeons score, left ventricular ejection fraction, mitral effective regurgitant orifice, indexed LV end-diastolic volume, and right ventricular systolic pressure were 4±1%, 62±3%, 0.55±0.2 cm(2), 58±13 cc/m(2), and 37±15 mm Hg, respectively. Forty-five percent of patients had flail. Median log-transformed BNP and LV-GLS were 4.04 (absolute brain natriuretic peptide: 60 pg/dL) and -20.7%. At 7.7±2 years, death occurred in 41 patients (9%; 0% at 30 days). On Cox analysis, a higher Society of Thoracic Surgeons score (hazard ratio 1.55), higher baseline right ventricular systolic pressure (hazard ratio 1.11), more abnormal LV-GLS (hazard ratio 1.17), and higher median log-transformed BNP (hazard ratio 2.26) were associated with worse longer-term survival (all P<0.01). Addition of LV-GLS and median log-transformed BNP to a clinical model (Society of Thoracic Surgeons score and baseline right ventricular systolic pressure) provided incremental prognostic utility (χ(2) for longer-term mortality increased from 31-47 to 61; P<0.001). In asymptomatic patients with significant primary mitral regurgitation and preserved left ventricular ejection fraction who underwent mitral valve surgery, brain natriuretic peptide and LV-GLS provided synergistic risk stratification, independent of established factors.

Effect of Pulmonary Vascular Pressures on Long-Term Outcome in Patients With Primary Mitral Regurgitation

BackgroundPrimary mitral regurgitation (MR) is a growing health problem due to the aging population. ObjectivesThe purpose of this study was to assess the impact of baseline pulmonary hypertension on long-term outcomes in patients with significant primary MR and preserved left ventricular ejection fraction (LVEF). MethodsWe studied 1,318 patients with ≥3+ primary MR and LVEF ≥60% using echocardiography at rest; they were evaluated at our center from 2005 to 2008. Baseline clinical and echocardiography data were recorded, and the Society of Thoracic Surgeons (STS) score was calculated. The primary outcome was death. ResultsMean STS score was 3.98 ± 1%; 54% of patients were in New York Heart Association (NYHA) functional class I and 31% were in NYHA functional class II; and 18% had atrial fibrillation (AF). Mean LVEF, mitral effective regurgitant orifice, indexed LV end-systolic diameter (LVESD), and right ventricular systolic pressure (RVSP) were 62 ± 2%, 0.56 ± 0.30 cm2, 1.6 ± 0.3 cm/m2, and 37 ± 14 mm Hg, respectively. At 7.1 ± 2.0 years, 86% had mitral valve (MV) surgery. Death occurred in 130 (10%) patients. On Cox multivariable analysis, baseline RVSP, together with age, baseline NYHA functional class, pre-operative AF, coronary artery disease, and indexed LVESD were associated with a higher rate of longer term mortality (all p < 0.01), whereas MV surgery (as a time-dependent covariate) was associated with improved survival (p < 0.001). Addition of RVSP to the STS score significantly reclassified the risk for longer term mortality (integrated discrimination index: 0.07; p < 0.001); 77% patients who died had RVSP ≥35 mm Hg. ConclusionsIn patients with significant primary MR and preserved LVEF, baseline RVSP is independently associated with long-term survival. Impact of RVSP is progressive and not confined to those with the highest baseline values.

Abstract 17282: Concordance of Mitral Leaflet Chordal Measurements Using Different Echocardiographic Techniques and Surgical Approaches: Implications for Mitral Valve Repair

Objectives: In patients with significant primary mitral regurgitation (PMR), the success of mitral valve repair (MVr) depends upon precise preop planning, including accurate assessment of chordal length. Both 2-dimentional (2D) &amp; 3-dimentional (3D) transthoracic (TTE) &amp; transesophageal (TEE) echocardiography visualize anterior and posterior chords. We sought to assess concordance of echo-based MV chordal measurements against direct intraop (robotic vs. midline) measurements. Methods: After informed consent, we prospectively enrolled 56 consecutive patients (59±11 years, 86% men) who underwent MVr (52% robotic, 48% sternotomy) between 12/14-6/15 by a single experienced surgeon. The lengths of anterior &amp; posterior MV chords were measured in 2-, 3-, &amp; 4-chamber views on preop 2D/3D TTE &amp; 2D/3D TEE (Philips &amp; General Electric) &amp; were compared to intraop length of the most perpendicular normal anterior &amp; posterior chords. All measurements were performed in a blinded manner &amp; noninvasive measurements were compared against intraop measurements using intraclass correlation coefficient (ICC). Results: Intraoperatively, the mean lengths of anterior &amp; posterior chords were 2.02±0.4 &amp; 1.81±0.4 cm, respectively. For the anterior chords, the mean lengths on 2D &amp; 3D TTE were 1.96±0.3 &amp; 1.96±0.3 cm, respectively, while they were 1.99±0.3 &amp; 1.93±0.3 cm on 2D &amp; 3D TEE, respectively. Similarly, for posterior chords, the mean length on 2D &amp; 3D TTE was 1.90±0.3 &amp; 1.89±0.3 cm, while they were 1.91±0.3 &amp; 1.90±0.3 cm on 2D &amp; 3D TEE, respectively. Data on ICC’s (for the concordance of the whole group &amp; separated on different surgical approaches) are shown in Figure. Conclusion: There is high concordance in measurement of anterior MV chords by 2D/3D TTE/TEE with surgical techniques. However, concordance for posterior chord measurement is less accurate, especially when a robotic approach is used. In such patients, precise preop planning using imaging (including tomography) may be crucial.

Abstract 15062: Incremental Prognostic Utility of LV Global Longitudinal Strain and Functional Capacity in Asymptomatic Patients With Significant Primary Mitral Regurgitation and Preserved Left Ventricular Ejection Fraction Undergoing Rest-Stress Echocardiography

Background: Outcomes after mitral valve (MV) surgery for primary mitral regurgitation (PMR) are excellent; however surgical timing in asymptomatic PMR &amp; preserved left ventricular ejection fraction (LVEF) remains challenging. We assessed the incremental utility of resting LV-global longitudinal strain (LV-GLS) &amp; exercise variables in asymptomatic patients with ≥3+ PMR &amp; preserved LVEF (≥60%) who underwent rest-stress echocardiography. Methods: We included 737 such patients (58±13 years, 68% men) between 2000-11. Clinical, resting (including LV-GLS using Velocity Vector Imaging &amp; right ventricular systolic pressure or RVSP) &amp; exercise stress echo (metabolic equivalents or METs) data were recorded. Society of Thoracic Surgeons (STS) score was calculated. Primary events were death &amp; heart failure admission. Results: Hypertension, atrial fibrillation (AF) and coronary artery disease were seen in 48%, 13% &amp; 10% patients. Posterior, anterior &amp; bileaflet prolapse were noted in 46%, 9% &amp; 45% (20% had flail). Mean STS score, resting LVEF, resting RVSP, exercise MET’s &amp; % age-gender predicted MET’s were 1.5±1, 62±2%, 31±12 mmHg, 9.8±3 &amp; 115±27 respectively. 65% underwent MV surgery with mean time to surgery 13±22 months. At 6.2±3 years, events occurred in 61 (8%) patients (death in 33 patients). On multivariable Cox survival analysis, higher rest RVSP (Hazard ratio or HR 1.04), lower % age-gender predicted METS (HR 1.11), lower LV-GLS (HR 1.42), higher STS score (HR 1.12) &amp; AF (HR 2.23) were significantly associated with events (all p&lt;0.05). Association of MV surgery (time-dependent covariate) with outcomes was not significant (HR 0.63 [0.38-1.07, p=0.1). Figure 1a shows an incremental model with association to outcomes &amp; 1b shows survival curves, based on LV-GLS better/worse than median (-21.7%). Conclusions: In asymptomatic patients with ≥3+ PMR &amp; preserved LVEF, lower baseline LV-GLS &amp; %age-gender predicted METs are associated with long-term adverse events.

Abstract 14693: Incremental Utility of BNP and LV Global Longitudinal Strain in Predicting Post-operative LV Systolic Dysfunction and Outcomes in Asymptomatic Patients With Significant Primary Mitral Regurgitation Undergoing Mitral Valve Surgery

Background: Outcomes after mitral valve (MV) surgery for primary mitral regurgitation (PMR) are excellent. However, some patients have a drop in post-op left ventricular ejection fraction (LVEF), despite preserved pre-op LVEF. In asymptomatic patients with ≥3+ PMR with preserved pre-op LVEF (≥60%) who underwent MV surgery for class IIa indications, we assessed the incremental ability of brain natriuretic peptide (BNP) &amp; LV-global longitudinal strain (LV-GLS) to predict a) a reduction in post-op LVEF &amp; b) long-term mortality. Methods: We included 448 such patients (61±12 years, 69% men) who had MV surgery between 2005-08. Clinical (including logBNP), baseline (including LV-GLS using Velocity Vector Imaging) &amp; follow up echo (LVEF) data were recorded. Post-op LVEF &lt;50% was considered abnormal. Society of Thoracic Surgeons (STS) score was calculated. Death during follow-up was recorded. Results: At baseline, atrial fibrillation, angiotensin inhibitors and betablockers &amp; MV flail were observed in 21%, 55%, 40% &amp; 45%, while mean STS score, logBNP, MV efective regurgitant orifice, LVEF, right ventricular systolic pressure &amp; LV-GLS were 4.1±1, 4.1±1, 0.55±0.2 cm2, 62±2%, 37±15 mm Hg &amp; -20.6±2%. 92% underwent MV repair (11% with coronary bypass) &amp; 94 (21%) had abnormal post-op LVEF. At 7.7±2 years, there were 30 (7%) deaths. Figure 1a shows logistic regression of association between abnormal post-op LVEF &amp; various factors. On multivariable Cox survival analysis, higher STS score (Hazard ratio or HR 1.55), lower LV-GLS (HR 1.17) &amp; higher logBNP (HR 2.26) were independent predictors of long-term mortality (all p&lt;0.05). Figure 1 b-c shows curves for long-term survival, based on LV-GLS &amp; log-BNP better or worse than median. Conclusions: In asymptomatic patients with ≥3+ PMR &amp; baseline LVEF ≥60% who underwent MV surgery, lower baseline LV-GLS &amp; higher logBNP were associated with abnormal post-op LVEF. Both, higher logBNP &amp; LV-GLS were associated with higher long-term mortality.

Prognostic Utility of Brain Natriuretic Peptide in Asymptomatic Patients With Significant Mitral Regurgitation and Preserved Left Ventricular Ejection Fraction

We sought to study the prognostic utility of serum brain natriuretic peptide (BNP) in patients with significant primary mitral regurgitation (MR) and preserved left ventricular (LV) ejection fraction (EF). Consecutive 548 asymptomatic patients (age 62 ± 13 years and 66% men) with ≥ 3 + primary MR and preserved LVEF on echo at rest, evaluated at our center from 2005 to 2008 were studied. Baseline clinical and echo data were recorded and the Society of Thoracic Surgeons (STS) score was calculated. Mean STS score was 4 ± 1%. Mean LVEF, mitral effective regurgitant orifice, indexed LV end-systolic diameter, and right ventricular systolic pressure (RVSP) were 62 ± 4%, 0.55 ± 0.3 cm(2), 1.6 ± 0.3 cm/m(2), and 38 ± 15 mm Hg; 43% had flail. Median log-transformed brain natriuretic peptide (lnBNP) was 4.1 (interquartile range 3.30 to 5.0), corresponding to an absolute BNP value of 60 pg/ml (only 13% had an absolute BNP value >250 pg/ml). At 7.4 ± 2 years, 493 patients (90%) had mitral surgery (92% repair) and nonmalignancy death occurred in 53 patients (10%). On multivariate Cox analysis, higher STS score (hazard ratio [HR] 1.50, 95% CI 1.20 to 1.88), higher baseline RVSP (HR 1.17, 95% CI 1.02 to 1.35), and higher ln BNP (HR 2.51, 95% CI 1.86 to 3.39) predicted death, whereas mitral surgery (HR 0.17, 95% CI 0.09 to 0.30) was associated with improved survival (all p <0.01). Eighty-nine percent of deaths occurred in patients with lnBNP >4.1. Addition of lnBNP to a model of STS score, baseline RVSP, and mitral surgery provided incremental prognostic utility (chi-square for mortality increased from 137 to 162, p <0.001). In conclusion, in asymptomatic patients with ≥ 3 + primary MR and preserved LVEF, the addition of BNP improved risk stratification and higher BNP independently predicted reduced survival.