Mitral Annular Dilatation Research Articles

Functional mitral regurgitation and left atrial myopathy in heart failure with preserved ejection fraction

Mild to moderate functional mitral regurgitation (MR) is common in patients with heart failure and preserved ejection fraction (HFpEF) where it is usually considered as an innocent bystander. We hypothesized that MR in HFpEF reflects greater left atrial (LA) myopathy, leading to more adverse haemodynamics and poorer exercise reserve. Patients with HFpEF (n= 280) with and without MR underwent echocardiography, invasive haemodynamic exercise testing, and expired gas analysis. As compared to non-MR-HFpEF (n= 163), patients with MR-HFpEF (n= 117; 78 mild and 39 moderate, central jet in 90%) were older, more likely female, with lower body mass and higher prevalence of atrial fibrillation (AF). HFpEF patients with MR displayed greater LA volume, reduced LA strain and compliance, and greater mitral annular dilatation, which was strongly correlated with LA dilatation (r=0.63, P< 0.0001) but was only weakly related to left ventricular remodelling (r=0.37). Patients with MR-HFpEF displayed worse biventricular function, more adverse pulmonary haemodynamics, impaired pulmonary vasodilatation, blunted right ventricular reserve, and reduced cardiac output with exercise as compared to non-MR-HFpEF. Importantly, these findings were maintained after excluding patients with HFpEF and AF, suggesting a role for LA myopathy in contributing to MR in HFpEF, independent of rhythm. Functional MR in patients with HFpEF reflects LA myopathy, even in the absence of AF, and is associated with greater haemodynamic severity of disease and poorer functional capacity. Further study is required to better define causal mechanisms and potential treatments for MR and LA dysfunction in patients with HFpEF.

P1754 Regional left ventricular longitudinal myocardial dysfunction in mitral valve prolapse could be primary

Abstract Background Regional left ventricular dysfunction in patients with mitral valve prolapse (MVP) and normal ejection fraction has been described by different Authors, and recent data point to a dysfunction (prevalently longitudinal strain) of the myocardium of the LV base secondary to dilatation of the mitral annulus. Purpose To investigate degree and extent of regional LV dysfunction and its mechanisms in patients with MVP, severe regurgitation and normal global systolic function, compared to patients with equivalent degree of regurgitation but functional etiology (FMR). Methods Speckle-tracking echocardiography was performed in 30 controls (N), and in severe primary (MVP, n= 50) or functional (FMR, n= 20) mitral regurgitation, to measure global, regional and segmental longitudinal peak systolic strain (LPSS, %), and time delay of peak maximum strain (TTPd, ms, calculated as time to peak maximum strain - time of aortic valve closure). Maximum and minimum mitral annulus diameters and area were measured with 3D echo. We also evaluated as recommended: LV end-diastolic volume index (EDVi, ml/m2), ejection fraction (EF, %), and left atrial end-systolic volume index (LAESVi, ml/m2) with 2D echo; LV stroke volume index, and non-invasive pulmonary systolic (PSP, mmHg) and diastolic pressures (PDP), mmHg) with Doppler echo. Results Age, heart rate, BSA and systolic blood pressure were similar between groups. Atrial fibrillation was present in 34% of MVP and 71% of FMR patients. LV EF was normal in MVP and reduced in FMR (43 ± 14 % vs N, p&amp;lt;.001). LV EDVi (MVP: 77 ± 20 ml/m2; FMR: 107 ± 35, both p&amp;lt;.001 vs N) and LAESVi (MVP: 91 ± 26 ml/m2; FMR: 80 ± 30, both p&amp;lt;.001 vs N) were similarly increased (volume overload) in MVP and FMR, as were PSP (MVP: 42 ± 23 ml/m2; FMR: 52 ± 25, both p&amp;lt;.001 vs N) and PDP (MVP: 16 ± 6 ml/m2; MVP: 15 ± 5, both p&amp;lt;.001 vs N). In FMR, LPSS was reduced globally (-12.8 ± 3.3, p&amp;lt;.001 vs N and MVP) and similarly at LV base, papillary and apical levels. In contrast, in MVP global (-19.4 ± 3.7%) and apical (-23.4 ± 4.5%) LPSS were normal, whereas LV base (-12.3 ± 5.8%, p=.003 vs N) and papillary (-17.1 ± 4%, p=.024 vs N) LPSS were reduced; further, LPSS reduction was localized to the anterior (-16 ± 4, p=.028 vs N), lateral (-17 ± 5, p=.006 vs N) and posterior (-16 ± 6, p=.007 vs N) segments, and was associated with an increased TTPd in the same segments in MVP but not in FMR patients. At multivariate analysis, degree and localisation of regional myocardial dysfunction in patients with MVP was not related to the prolapsing scallop, dimension of the mitral annulus, degree of volume overload or pulmonary pressures, or stroke volume index. Conclusions In patients with MVP, severe regurgitation and normal EF, there is a specific dysfunction pattern of regional LV longitudinal function which appears to be primary and not dependent on the degree of preload increase, mitral annulus dilatation, or localization of the prolapsing scallop.

Transcatheter MitraClip repair alters mitral annular geometry \u2013 device induced annular remodeling on three-dimensional echocardiography predicts therapeutic response

BackgroundEchocardiography (echo) is widely used to guide therapeutic decision-making for patients being considered for MitraClip. Relative utility of two- (2D) and three-dimensional (3D) echo predictors of MitraClip response, and impact of MitraClip on mitral annular geometry, are uncertain.MethodsThe study population comprised patients with advanced (> moderate) MR undergoing MitraClip. Mitral annular geometry was quantified on pre-procedural 2D transthoracic echocardiography (TTE) and intra-procedural 3D transesophageal echocardiography (TEE); 3D TEE was used to measure MitraClip induced changes in annular geometry. Optimal MitraClip response was defined as ≤mild MR on follow-up (mean 2.7 ± 2.5 months) post-procedure TTE.ResultsEighty patients with advanced MR underwent MitraClip; 41% had optimal response (≤mild MR). Responders had smaller pre-procedural global left ventricular (LV) end-diastolic size and mitral annular diameter on 2D TTE (both p ≤ 0.01), paralleling smaller annular area and circumference on 3D TEE (both p = 0.001). Mitral annular size yielded good diagnostic performance for optimal MitraClip response (AUC 0.72, p < 0.01). In multivariate analysis, sub-optimal MitraClip response was independently associated with larger pre-procedural mitral annular area on 3D TEE (OR 1.93 per cm2/m2 [CI 1.19–3.13], p = 0.007) and global LV end-diastolic volume on 2D TTE (OR 1.29 per 10 ml/m2 [CI 1.02–1.63], p = 0.03). Substitution of 2D TTE derived mitral annular diameter for 3D TEE data demonstrated a lesser association between pre-procedural annular size (OR 5.36 per cm/m2 [CI 0.95–30.19], p = 0.06) and sub-optimal MitraClip response. Matched pre- and post-procedural TEE analyses demonstrated MitraClip to acutely decrease mitral annular area and circumference (all p < 0.001) as well as mitral tenting height, area, and volume (all p < 0.05): Magnitude of MitraClip induced reductions in mitral annular circumference on intra-procedural 3D TEE was greater among patients with, compared to those without, sub-optimal MitraClip response (>mild MR) on followup TTE (p = 0.017); greater magnitude of device-induced annular reduction remained associated with sub-optimal MitraClip response even when normalized for pre-procedure annular circumference (p = 0.028).ConclusionsMitraClip alters mitral annular geometry as quantified by intra-procedural 3D TEE. Pre-procedural mitral annular dilation and magnitude of device-induced reduction in mitral annular size on 3D TEE are each associated with sub-optimal therapeutic response to MitraClip.

Functional mitral regurgitation, updated: ventricular or atrial?

Lone atrial fibrillation (AF) can cause functional mitral regurgitation (MR), commonly referred to as "atrial functional MR (AFMR)." This type of MR has recently received much attention as an important cause of heart failure, and it represents a considerable therapeutic target in heart failure patients with AF. Mitral annular dilatation due to left atrial (LA) dilatation can be recognized as an original cause of AFMR, whereas the exact cascade of AFMR etiologies has not been established. AFMR is typically classified as Carpentier type I, and is likely to have a central jet. In contrast, a proportion of AFMR is classified as a combination of Carpentier type I for a flattened anterior mitral leaflet and Carpentier type IIIb for a tethered posterior mitral leaflet and is likely to have an eccentric jet directed toward the LA posterior wall. The traditional functional MR occurring in patients with left ventricular (LV) dilatation and/or systolic dysfunction, which is classified as Carpentier type IIIb, has since been designated "ventricular functional MR (VFMR)" to distinguish it from AFMR. Traditional VFMR, newly recognized AFMR, and their etiologic relations to LV/LA size and function are discussed in this review article.

P6491Predictive effect of mitral annular size on persistent mitral valve dysfunction after transcatheter edge-to-edge mitral valve repair for functional mitral regurgitation

Abstract Background In patients with functional mitral regurgitation (FMR), deformation of the mitral valve (MV) apparatus leads to deteriorating coaptation of both leaflets. The MV geometry is essential to predict procedural success of using the MitraClip™ for FMR patients. Persistent such mitral regurgitation (MR) and post-procedural mitral stenosis (MS) are parameters for an increasing mortality rate after MitraClip implantation. The anterior-to-posterior mitral annulus diameter (MAD) is simple to evaluate with a high reproducibility rate. However, the predictive effect has not been determined to date. Purpose We evaluated the predictive effect of baseline anterior-to-posterior MAD on persistent MV dysfunctions after MitraClip™ implantation. Methods We investigated the prevalence of procedural failure (MR at discharge &gt; grade 2+) and post-procedural MS (mean transmitral gradient (mTMG) at discharge ≥6 mmHg) in a patient cohort with FMR (n=190), who underwent MitraClip™ implantation. We measured the MV apparatus geometry on mid-systole using transoesophageal echocardiography before the index procedure. The MAD was stratified by interquartile ranges (IQR) in the comparison. (≤34 mm, 35 to 37 mm, 38 to 40 mm, and ≥41 mm, respectively) Results The mean age was 75±9 years, and 63 patients (33%) were female. The mean left ventricular ejection fraction was 34±14%. Moderate-to-severe (3+) or severe MR (4+) were documented in all patients before the procedure. Transthoracic echocardiography at discharge revealed residual MR (&gt;2+) in 10 patients (5%) and post-procedural MS in 13 patients (7%), in which one patient presented with both residual MR and MS. After stratification by the IQRs of MAD, there were significant differences in body weight (p&lt;0.001), height (p&lt;0.001), and body surface area (p&lt;0.001), but no significant differences in the other baseline characteristics. Notably, significant differences in the prevalence of procedural failure (p=0.004) and post-procedural MS (p=0.022) were observed among the groups. (Figure) Specifically, in the cohort with the 4th IQR (MAD ≥41 mm, n=44), procedural failure was observed in 7 patients (16%), although the prevalence was only 2% in the other IQR groups. Moreover, the cohorts with the 1st and 2nd IQR presented with higher prevalence of post-procedural MS (6 of 46 patients (13%) in the 1st IQR group, and 6 of 51 (12%) in the 2nd IQR group) than those with the 3rd and 4th IQRs. (1 of 49 patients (2%) in the 3rd IQR, and none of 44 patients in the 4th IQR) Figure 1 Conclusion In this analysis we showed that the mitral annulus size affected MV dysfunction after MitraClip™. Anterior-to-posterior MAD was useful to predict the procedural result. For FMR candidates with dilated mitral annulus larger than 40 mm, new-generation MitraClip-XTR™ system or other therapeutic concept such as annuloplasty may be reasonable to obtain satisfactory MV function.

Utilization of intra-aortic balloon pump to allow MitraClip procedure in patients with non-coapting mitral valve leaflets: a case series.

BackgroundThe MitraClip (MC) procedure was designed for high-risk surgical patients with severe mitral regurgitation (MR). Some patients do not meet the required anatomical criteria due to advanced left ventricular remodelling and mitral annular dilatation leading to leaflet tethering and insufficient coaptation surface. Theoretically, ‘temporary remodelling’ of the mitral valve apparatus by pharmacological and/or mechanical support using intra-aortic balloon pump (IABP) could improve leaflets coaptation.Case summaryWe report a case series of four patients with severe MR and non-coapting leaflets who underwent MC implantation. Sufficient coaptation was achieved only after insertion of IABP. The first patient presented with worsening heart failure and severe MR after a non-reperfused posterior wall myocardial infarction (MI), underwent a successful procedure with good results. The second patient presented with worsening heart failure secondary to rheumatic MR, and underwent MC procedure with good results after the insertion of IABP. The third patient developed worsening heart failure and severe MR 2 months after an acute inferior-lateral MI, and underwent a successful procedure. The fourth patient presented with respiratory failure, the patient underwent the procedure, but unfortunately died a few days following the procedure from multiorgan failure. In each case, the insertion of the IABP decreased annular mitral diameter and increased the coaptation surface as assessed by transoesophageal echocardiography.DiscussionFor patients suffering from symptomatic severe MR who are not suitable candidates for MC procedure, IABP system enabled us to overcome mitral leaflet gap and complete the MC procedure successfully.

Left ventricular geometry predicts optimal response to percutaneous mitral repair via MitraClip: Integrated assessment by two- and three-dimensional echocardiography.

To assess impact of left ventricular (LV) chamber remodeling on MitraClip (MClp) response. MitraClip is the sole percutaneous therapy approved for mitral regurgitation (MR) but response varies. LV dilation affects mitral coaptation; determinants of MClp response are uncertain. LV and mitral geometry were quantified on pre- and post-procedure two-dimensional (2D) transthoracic echocardiography (TTE) and intra-procedural three-dimensional (3D) transesophageal echocardiography (TEE). Optimal MClp response was defined as ≤mild MR at early (1-6 month) follow-up. Sixty-seven degenerative MR patients underwent MClp: Whereas MR decreased ≥1 grade in 94%, 39% of patients had optimal response (≤mild MR). Responders had smaller pre-procedural LV end-diastolic volume (94 ± 24 vs. 109 ± 25 mL/m2 , p = 0.02), paralleling smaller annular diameter (3.1 ± 0.4 vs. 3.5 ± 0.5 cm, p = 0.002), and inter-papillary distance (2.2 ± 0.7 vs. 2.5 ± 0.6 cm, p = 0.04). 3D TEE-derived annular area correlated with 2D TTE (r = 0.59, p < 0.001) and was smaller among optimal responders (12.8 ± 2.1 cm2 vs. 16.8 ± 4.4 cm2 , p = 0.001). Both 2D and 3D mitral annular size yielded good diagnostic performance for optimal MClp response (AUC 0.73-0.84, p < 0.01). In multivariate analysis, sub-optimal MClp response was associated with LV end-diastolic diameter (OR 3.10 per-cm [1.26-7.62], p = 0.01) independent of LA size (1.10 per-cm2 [1.02-1.19], p = 0.01); substitution of mitral annular diameter for LV size yielded an independent association with MClp response (4.06 per-cm2 [1.03-15.96], p = 0.045). Among degenerative MR patients undergoing MClp, LV and mitral annular dilation augment risk for residual or recurrent MR, supporting the concept that MClp therapeutic response is linked to sub-valvular remodeling.

75-Year-Old Man With Chest Pain and Dyspnea

75-Year-Old Man With Chest Pain and Dyspnea

Functional state of the myocardium and criteria for poor prognosis in mitral valve prolapse

Aim. Study of the fnctional state of left ventricular myocardium and determination of diagnostic criteria of poor prognosis of mitral valve prolapse. Methods. 151 patients (116 males and 35 females) with mitral valve prolapse (MVP) were examined. The average age was 34.8 ± 0.79 years. Division by the groups was performed depending on the severity of structural changes of the valve and width of the cusps: group 1 included 54 patients with classic form of MVP (cusp width ≥5 mm), group 2 included 55 patients with cusp width ≥3 mm, group 3 included 42 patients with MV cusp width less than 3 mm. All patients underwent complex clinical functional examination of cardiovascular system. The state of systolic and diastolic cardiac function was assessed using stationary high-tech ultrasound scanner «Philips iE-33» (Philips, Holland) according to conventional technique with determination of standard heart parameters and calculation of intracardiac hemodynamic parameters. Echocardiography was performed on admission and 12 to 18 month later. Results. The study revealed that the most prominent changes of cardiohemodynamics and unfavorable disease course were observed in 72.2 % of patients with classic form of MVP (group 1). Patients with non-classic form of MVP (group 2) also had poor prognosis in 27.8 % of cases. Diagnostic criteria of poor prognosis of MVP according to echocardiography were determined: severe mitral regurgitation (degree ≥III), mitral valve cusp thickness during diastole over 6 mm, left ventricle dilation (EDS ≥ 60 mm; ESS ≥ 36 mm), left atrial dilation (anterior posterior size of LA ≥ 40 mm, LA volume ≥ 80 ml), mitral annulus dilation (diameter of MA ≥ 35 mm). Conclusion. Differences of functional state of the myocardium of left ventricle were revealed depending on the type of mitral valve prolapse caused by the severity of connective tissue dysplasia. In classic form of MVP more severe disorders of intracardiac hemodynamics were observed as well as more severe mitral insufficiency.

Borderline left ventricular ejection fraction is associated with alterations in mitral annular size and function. Results from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study

Morphology and function of the mitral annulus (MA) shows alterations in different valvular (for instance in mitral regurgitation) and non-valvular disorders (for instance in certain cardiomyopathies, cardiac amyloidosis). The aim of the present study was to examine the relationship between MA morphologic and functional properties and three-dimensional speckle-tracking echocardiography- (3DSTE) derived left ventricular (LV) ejection fraction (EF) in subjects with normal versus borderline LV-EF. The present study comprised 146 volunteers (mean age: 32.0 ± 11.4 years; 74 males) in whom complete two-dimensional Doppler echocardiography was performed with a negative result extended with 3DSTE. The population was further divided into two groups according to their 3DSTE-derived LV-EF (borderline 50-54% versus ≥55%). In cases with borderline LV-EF, higher LV end-systolic LV volumes and lower LV longitudinal strain could be measured. All end-systolic and end-diastolic MA diameter, area and perimeter data proved to be higher in cases with borderline LV-EF. In these subjects, MA functional parameters proved to be lower as well. In contrast, LV-EF showed correlations neither with end-systolic and end-diastolic MA dimensions nor with MA functional parameters. 3DSTE-derived borderline LV-EF is associated with MA dilatation and functional impairment. Orv Hetil. 2018; 159(50): 2129-2135.

New Device for the Treatment of Functional Ischemic Mitral Regurgitation: Proof of Concept in an In Vitro Model.

Optimal surgical treatment of functional ischemic mitral regurgitation (FIMR) is still controversy. Due to the underlying pathophysiology, stand-alone ring annuloplasty is assumed with a high recurrence rate of mitral regurgitation, thus additional subvalvular repair techniques might improve the results. This in vitro study introduces a new device for subvalvular mitral valve repair. We developed a new device for subvalvular mitral valve repair, consisting of two frames for papillary muscle (PM) attachment, which are connected with two holding bars serving for fixation of the device on an annuloplasty ring. In the first experimental run, porcine mitral valves including the chordae tendineae and PMs were fixated on a holding device, consisting of a holding ring simulating mitral annulus dilation and height-adjustable frames for PM attachment simulating leaflet tethering. In vitro regurgitant volume was determined in a pulse duplicator. Afterward, the frames for PM attachment were replaced by our newly developed device and the measurements were repeated. In the model simulating FIMR, the regurgitant volume was 44.3 ± 12.38 mL/stroke. After subvalvular reconstruction with our new device, the regurgitant volume was significantly reduced to 33.1 ± 11.68 mL/stroke (p = 0.009). In this specific in vitro model, our new device for subvalvular mitral valve reconstruction led to a significant reduction of the regurgitant volume, thus representing a promising technique to potentially improve the results of mitral reconstruction in ischemic functional mitral valve regurgitation. Additional studies are required to further investigate and improve our device.

Quantitative analysis of mitral valve morphology in atrial functional mitral regurgitation using real-time 3-dimensional echocardiography atrial functional mitral regurgitation

BackgroundAtrial fibrillation (AF) can result in atrial functional mitral regurgitation (MR), but the mechanism remains controversial. Few data about the relationship between the 3-dimensional morphology of the MV and the degree of MR in AF exist.MethodsReal-time 3-dimensional transesophageal echocardiography (3D-TEE) of the MV was acquired in 168 patients with AF (57.7% persistent AF), including 25 (14.9%) patients with moderate to severe MR (the MR+ group) and 25 patients without AF as controls. The 3-dimensional geometry of the MV apparatus was acquired using dedicated quantification software.ResultsCompared with the group of patients with no or mild MR (the MR- group) and the controls, the MR+ group had a larger left atrium (LA), a more dilated mitral annulus (MA), a reduced annular height to commissural width ratio (AHCWR), indicating flattening of the annular saddle shape, and greater leaflet surfaces and tethering. MR severity was correlated with the MA area (r2 = 0.43, P < 0.01) and the annulus circumference (r2 = 0.38, P < 0.01). A logistic regression analysis indicated that the MA area (OR: 1.02, 95% CI: 1.01–1.03, P < 0.01), AHCWR (OR: 0.24, 95% CI: 0.14–0.35, P = 0.04) and MV tenting volume (OR: 3.24, 95% CI: 1.16–9.08, P = 0.03) were independent predictors of MR severity in AF patients.ConclusionsThe mechanisms of “atrial functional MR” are complex and include dilation of the MA, flattening of the annular saddle shape and greater leaflet tethering.

Fatigue exhaustion of the mitral valve tissue

Sudden failure and rupture of the tissue is a rare but serious short-term complication after the mitral valve surgical repair. Excessive cyclic loading on the suture line of the repair can progressively damage the surrounding tissue and finally cause tissue rupture. Moreover, mechanical over-tension, which occurs in a diseased mitral valve, gradually leads to tissue floppiness, mitral annular dilation, and leaflet rupture. In this work, the rupture mechanics of mitral valve is studied by characterizing the fracture toughness exhaustion of healthy tissue. Results of this study show that fracture toughness of the posterior mitral valve is lower than its anterior counterpart, indicating that posterior tissue is more prone to failure. Moreover, the decrease in fracture toughness by increasing the number of fatigue cycles shows that excessive mechanical loading leads to progressive failure and rupture of mitral valve tissue within a damage accumulative process.

Abstract 573: Mechanical Stress Alters Cell Signaling and Extracellular Matrix Genes in Fetal Cardiac Valves

Objective: Prenatal hypertension leads to mitral annular dilation and is linked to changes in valvular extracellular matrix (ECM) and cell cycle genes including TGFβ-1, BMPs and FGF. We hypothesized that these changes are exacerbated by additional mechanical stress. Methods: Fetal sheep received 8 days of plasma infusion to induce hypertension (HTN, n=5) or lactated ringers solution (CTRL, n=4) starting at 126±2 days gestational age (dGA; term~145 days). Fetal mitral valve interstitial cells (VICs) were isolated at 134±1dGA, cultured in flexible, collagen-coated wells and subjected to 0% (static) or 18% equibiaxial stretch (1 Hz, 24 hrs). mRNA was isolated and qPCR was used to determine the effects of HTN and stretch on gene expression. Statistical analysis was performed via two-way ANOVA with Bonferroni correction. Results: Plasma infusion significantly increased the MAP of HTN fetuses (44.3±2.4 vs 61.6±1.1mmHg, p= 0.002). Change in gene expression is shown in Fig. 1; data are expressed relative to the CTRL/static group. Stretch, but not HTN, significantly increased FGF expression (p&lt;0.05). HTN and stretch each significantly increased expression of TGFβ-1, BMP-1 and -2. Stretch amplified the hypertension-induced increase in these 3 genes (p&lt;0.05 for all). Versican was unaltered by HTN or stretch. Conclusion: Our study demonstrates that early exposure to mechanical stress can shape cell signaling pathway responses in developing fetal cardiac valves, and these changes are amplified when exposed to a secondary stress. These data indicate that the prenatal environment has implications for postnatal cardiac valve function and risk for valvular disease in adulthood.

Very late presentation of anomalous origin of the left coronary artery from the pulmonary artery: case report

BackgroundAnomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary anomaly. The enlarged right coronary artery provides retrograde collaterals to supply the left ventricle then preferentially directs into the lower pressure pulmonary artery system causing coronary steal phenomenon. Few patients who survive through adulthood without surgery must have abundant, well-formed functioning collaterals with adequate perfusion of the left ventricle. We present the oldest reported patient with ALCAPA to undergo corrective surgery.Case presentationA 79-year-old woman presented with a 3-months history of worsening shortness of breath and orthopnea. Physical examination discovered a soft continuous murmur at the left upper chest. Transthoracic echocardiography demonstrated an unusual, tubular-like structure inside the interventricular septum with a turbulent flow from color Doppler. Moreover, there was a severe mitral regurgitation from posterior mitral leaflet restriction associated with ventricular remodeling in combination with mitral annular dilatation. Coronary angiography and coronary computed tomography angiography established the diagnostic hallmark of ALCAPA syndrome. Stress cardiovascular magnetic resonance perfusion imaging demonstrated no myocardial ischemia suggesting adequate collateral circulation. Remarkably, there was a left coronary ostial stenosis, which served as a protective mechanism against myocardia ischemia by limiting the steal effect. The patient successfully underwent the ligation of anomalous artery at its origin in combination with bioprosthetic mitral valve replacement. Her postoperative course was uneventful.ConclusionsThis case utilized multimodality imaging for delineating the course of abnormal vessels and helping to formulate therapeutic decision.

Systolic characteristics and dynamic changes of the mitral valve in different grades of ischemic mitral regurgitation \u2013 insights from 3D transesophageal echocardiography

BackgroundMitral regurgitation in ischemic heart disease (IMR) is a strong predictor of outcome but until now, pathophysiology is not sufficiently understood and treatment is not satisfying. We aimed to systematically evaluate structural and functional mitral valve leaflet and annular characteristics in patients with IMR to determine the differences in geometric and dynamic changes of the MV between significant and mild IMR.MethodsThirty-seven patients with IMR (18 mild (m)MR, 19 significant (moderate+severe) (s)MR) and 33 controls underwent TEE. 3D volumes were analyzed using 3D feature-tracking software.ResultsAll IMR patients showed a loss of mitral annular motility and non-planarity, whereas mitral annulus dilation and leaflet enlargement occurred in sMR only. Active-posterior-leaflet-area decreased in early systole in all three groups accompanied by an increase in active-anterior-leaflet-area in early systole in controls and mMR but only in late systole in sMR.ConclusionsIn addition to a significant enlargement and loss in motility of the MV annulus, patients with significant IMR showed a spatio-temporal alteration of the mitral valve coaptation line due to a delayed increase in active-anterior-leaflet-area. This abnormality is likely to contribute to IMR severity and is worth the evaluation of becoming a parameter for clinical decision-making. Further, addressing the leaflets aiming to increase the active leaflet-area is a promising therapeutic approach for significant IMR. Additional studies with a larger sample size and post-operative assessment are warranted to further validate our findings and help understand the dynamics of the mitral valve.

Good 5-Year Durability of Transapical Beating Heart Off-Pump Mitral Valve Repair With Neochordae

Transapical, beating heart, off-pump implantation of neochordae for repair of mitral valve (MV) prolapse is of increasing interest. The aim of this study was to evaluate long term results for MV repair using the NeoChord system (NeoChord, St. Louis Park, MN). Six patients underwent treatment for severe primary mitral regurgitation (MR) with the NeoChord DS1000 system as part of the initial device safety and feasibility Transapical Artificial Chordae Tendinae (TACT) trial at our institution (University of Leipzig-Heart Center, Leipzig, Germany). The primary pathology in all patients was isolated posterior leaflet prolapse of the P2 or P3 segment, or both. Successful repair resulting in no or trace MR was achieved in 5 of 6 patients by implantation of three neochordae under transesophageal echocardiographic guidance and normal left ventricular loading conditions. One patient underwent intraoperative conversion to an open MV replacement as a result of leaflet injury. The early postoperative course was uneventful in all remaining patients. Two patients had to undergo reoperation for recurrent MR at 3 and 16 months postoperatively. The remaining 3 patients were followed up for a period of 5 years. These patients were free of cardiac symptoms, and transthoracic examination showed trace or mild to moderate MR at 1-, 2-, and 5-year follow-up. A trend toward reverse remodeling of the left ventricle with no increase in mitral annular dilatation over 5 years was observed. In select patients, MV repair using the NeoChord system results in very good long-term results without recurrent prolapse, MR, or annular dilatation.

INSUFFICIENT MITRAL LEAFLET REMODELING CONTRIBUTES TO MITRAL REGURGITATION IN PATIENTS WITH ATRIAL FIBRILLATION: A QUANTITATIVE THREE-DIMENSIONAL TRANSESOPHAGEAL ECHOCARDIOGRAPHIC STUDY

Mitral annulus dilatation is common in patients with atrial fibrillation (AF) but only some of them develop mitral regurgitation (MR). We hypothesize that insufficient mitral leaflet size relative to annular dilatation compromises systolic leaflet closure and contributes to MR in patients with AF.

P157What causes mitral annulus dilatation - A three-dimensional transesophageal study

P157What causes mitral annulus dilatation - A three-dimensional transesophageal study

Modelling of Lesions Associated with Functional Mitral Regurgitation in an Ex Vivo Platform.

Functional mitral regurgitation (FMR) is a complex pathology involving valvular and subvalvular structures reconfiguration, and its treatment is considered challenging. There is a lack of experimental models allowing for reliable preclinical FMR treatments' evaluation in a realistic setting. A novel approach to simulate FMR was developed and incorporated into an ex vivo passive beating heart platform. FMR was obtained by dilating the mitral annulus (MA) mainly in the antero-posterior direction and displacing the papillary muscles (PMs) apically and laterally by ad hoc designed and 3D printed dilation and displacing devices. It caused hemodynamic and valve morphology alterations. Isolated MA dilation (MAD) led to significantly increased antero-posterior distance (A-P) and decreased coaptation height (CH), tenting area (TA) and systolic leaflets angulation, resembling clinically recognized type I of mitral regurgitation with normal leaflet motion. Whereas concomitant MAD with PM displacement caused an increase in A-P, TA, CH. This geometrical configuration replicated typical determinants of type IIIb lesion with restricted leaflet motion. The proposed methods provided a realistic and repeatable ex vivo FMR model featuring two lesions clinically associated with the pathology. It bears a promise to be successfully utilized in preclinical studies, clinical training and medical education.