Functional Ischemic Mitral Regurgitation Research Articles

Outcomes in Patients With High Transmitral Gradient After Mitral Valve Transcatheter Edge-to-Edge Repair for Mitral Regurgitation

Despite being highly effective in reducing residual mitral regurgitation and improving outcomes, mitral valve transcatheter edge-to-edge repair (MV-TEER) may be associated with high postprocedural residual mitral gradient (rMG). Conflicting results have been reported regarding the relation between rMG and adverse events. This study aimed to evaluate the predictors and the impact of elevated rMG after MV-TEER on clinical events in patients with functional mitral regurgitation (FMR) at 2 years follow-up. We selected a cohort of 864 patients with FMR who were treated with MV-TEER enrolled in the multicentre Italian Society of Interventional Cardiology (GISE) registry of transcatheter treatment of mitral valve regurgitation (GIOTTO). Patients were stratified into tertiles according to rMG. The primary clinical end point was a composite of all-cause death and hospitalization because of heart failure at 2-year follow-up. Overall, 269 patients (31.5%) with an rMG <3 mm Hg, 259 (30.3%) with an rMG ≥3/<4 mm Hg, and 326 (38.2%) with an rMG ≥4 mm Hg were considered. At multivariate logistic regression, ischemic FMR etiology, baseline MG, and the number of implanted clips were independent predictors of an rMG ≥4 mm Hg. Clinical follow-up was available in 570 patients (63.2%). Patients with an rMG ≥4 mm Hg experienced higher rates of the composite end point than patients of the other tertiles (51.1%, vs 42.3% vs 40.8% log-rank test: p=0.033). In multivariate Cox's regression, both rMG ≥4 mm Hg (hazard ratio 1.54, 95% confidence interval 1.14 to 2.08) and residual mitral regurgitation ≥2+ (hazard ratio 1.36, 95% confidence interval 1.01 to 1.83) were independent predictors of adverse events at 2-year follow-up. In conclusion, we demonstrated that real-world patients who underwent MV-TEER who show an rMG ≥4 mm Hg are at higher risk of death or hospitalization because of heart failure during a 2-year follow-up. Further studies will be needed to confirm our results.

Myocardial Contractile Mechanics in Ischemic Mitral Regurgitation: Multicenter Data Using Stress Perfusion Cardiovascular Magnetic Resonance

BackgroundLeft ventricular (LV) ischemia has been variably associated with functional mitral regurgitation (FMR). Determinants of FMR in patients with ischemia are poorly understood. ObjectivesThis study sought to test whether contractile mechanics in ischemic myocardium underlying the mitral valve have an impact on likelihood of FMR. MethodsVasodilator stress perfusion cardiac magnetic resonance was performed in patients with coronary artery disease (CAD) at multiple centers. FMR severity was confirmed quantitatively via core lab analysis. To test relationship of contractile mechanics with ischemic FMR, regional wall motion and strain were assessed in patients with inducible ischemia and minimal (≤5% LV myocardium, nontransmural) infarction. ResultsA total of 2,647 patients with CAD were studied; 34% had FMR (7% moderate or greater). FMR severity increased with presence (P < 0.001) and extent (P = 0.01) of subpapillary ischemia: patients with moderate or greater FMR had more subpapillary ischemia (odds ratio [OR]: 1.13 per 10% LV; 95% CI: 1.05-1.21; P = 0.001) independent of ischemia in remote regions (P = NS); moderate or greater FMR prevalence increased stepwise with extent of ischemia and infarction in subpapillary myocardium (P < 0.001); stronger associations between FMR and infarction paralleled greater wall motion scores in infarct-affected territories. Among patients with inducible ischemia and minimal infarction (n = 532), wall motion and radial strain analysis showed impaired subpapillary contractile mechanics to associate with moderate or greater FMR (P < 0.05) independent of remote regions (P = NS). Conversely, subpapillary ischemia without contractile dysfunction did not augment FMR likelihood. Mitral and interpapillary dimensions increased with subpapillary radial strain impairment; each remodeling parameter associated with impaired subpapillary strain (P < 0.05) independent of remote strain (P = NS). Subpapillary radial strain (OR: 1.13 per 5% [95% CI: 1.02-1.25]; P = 0.02) and mitral tenting area (OR: 1.05 per 10 mm2 [95% CI: 1.00-1.10]; P = 0.04) were associated with moderate or greater FMR controlling for global remodeling represented by LV end-systolic volume (P = NS): when substituting sphericity for LV volume, moderate or greater FMR remained independently associated with subpapillary radial strain impairment (OR: 1.22 per 5% [95% CI: 1.02-1.47]; P = 0.03). ConclusionsAmong patients with CAD and ischemia, FMR severity and adverse mitral apparatus remodeling increase in proportion to contractile dysfunction underlying the mitral valve.

Functional ischemic mitral regurgitation in acute myocardial infarction: Importance of changes in left ventricular shape and regional function

Functional ischemic mitral regurgitation (IMR) is common in patients with ischemic left ventricular dysfunction after myocardial infarction, and significantly worsens prognosis. The aim of this study is to determine the relative importance of the global and regional left ventricular (LV) remodelling in the occurrence of IMR. Eighty-one patients (mean age = 61 ± 11 years) admitted with acute myocardial infarction (AMI) were screened. Patients with atrial fibrillation and organic valvular diseases were excluded from the study. Echocardiography (two-dimensional and Doppler echocardiograms) was performed in the first week after admission. The 81 patients were divided in 2 groups: with IMR (group1 = 39 patients) and without IMR (group2 = 42 patients). LV volumes were calculated by apical biplane Simpson's rule. The LV wall-motion score (WMS) index was obtained in a 17-segment model according to established methods. To identify the influence of regional wall-motion impairment for each individual LV segment, the mean WMS was calculated for each segment and compared between the 2 groups. The echocardiographic parameters that were associated with IMR were: LV dilatation and sphericity ( P < 0.0001), reduced ejection fraction ( P < 0.0001), inferior ( P < 0.001) inferolateral ( P = 0.01) and anterolateral ( P = 0.02) asynergy. The results of this study indicate the importance of abnormalities of both LV geometry and regional wall motion in the pathogenesis of IMR after myocardial infarction. Clinically, these findings imply that myocardial salvage by early coronary revascularisation may improve outcome by preserving LV function and decreasing the incidence of IMR.

Mitral Valve Translocation: A Novel Operation for the Treatment of Secondary Mitral Regurgitation

BackgroundConventional annuloplasty repair of secondary (functional) ischemic mitral regurgitation (IMR) is associated with a 60% recurrence of moderate or greater mitral regurgitation at 2 years. We developed a novel repair technique for IMR that addresses the underlying geometric alterations of the mitral valve apparatus and compared outcomes with those of conventional repair in a swine model. MethodsChronic IMR was induced by percutaneous embolization of the circumflex artery. Swine with severe IMR (median 9 weeks after infarction) underwent undersized rigid annuloplasty (n = 5) or translocation repair (n = 6). Translocation repair consisted of detaching the mitral valve en bloc at the annulus, creating a 1 cm wide frustum-shaped pericardial patch, and suturing the outer circumference of the patch to the annulus and inner circumference to the mitral valve. ResultsOperative survival was 92% (11 of 12). All animals had none/trace residual central mitral regurgitation, and mean inflow gradients were similar (1 mm Hg [interquartile range, 1 to 2] vs 2 mm Hg [interquartile range, 1 to 2]; P = .75) in the annuloplasty and translocation groups, respectively. Median coaptation length marginally improved in conventional swine (3 to 4 mm, P = .05), but dramatically improved in translocation swine (3 to 8 mm, P = .003). Posterior leaflet angle increased from 39 to 80 degrees (P = .05) in annuloplasty swine but decreased from 50 to 31 degrees (P = .03) in translocation swine. The posterior leaflet was immobile after annuloplasty but had preserved motion after translocation (excursion, 1 degree vs 24 degrees; P = .045). ConclusionsMitral valve translocation effectively treats mitral regurgitation by relieving leaflet tethering. Compared with annuloplasty, mitral valve translocation creates a larger surface of coaptation and preserves leaflet mobility without compromising diastolic function.

Clinical and Echocardiographic Predictors of Reduced Survival in Patient with Functional Mitral Regurgitation

Functional mitral regurgitation (FMR) is associated with a poor outcome in patients with reduced left ventricular ejection fraction (LVEF). Two recent studies of percutaneous mitral valvular repair therapy reported disparate results, likely due in part to variable risk among FMR patients. The aim of this study is to define echocardiographic factors of prognostic significance in FMR patients, and particularly to compare ischemic and nonischemic FMR. We followed three hundred sixteen consecutive patients (age 60 ± 14 years, men 70%) with FMR and LVEF ≤ 35% between January 2010 and December 2015 (mean follow-up 3.7 years). Patients were categorized into ischemic (39.6%) and nonischemic (60.4%). MR was graded according to the American Society of Echocardiography guidelines. Although echo findings were similar between ischemic and nonischemic patient, the incidence of death, heart transplantation (HT), or LVAD implantation was higher in ischemic than in nonischemic patients (Log rank p = 0.001). In age and gender adjusted multivariate (11 variables) Cox regression analysis, left atrium volume index (LAVI) was associated with death, HT, or LVAD with hazard ratio of 2.1 for patients with FMR (p = 0.003). LAVI greater than 48.7 mL/m2 predicts adverse outcome in both nonischemic and ischemic FMR (AUC 0.62, p < 0.001). Combined ischemic FMR with LAVI ≥ 48.7 mL/m2 had the highest incident rate of all groups. In conclusion, despite similar LV function and MR severity, ischemic FMR patients had higher mortality than nonischemic patients. Of all echocardiographic parameters, an LAVI ≥ 48.7 mL/m2 predicted adverse clinical outcome.

Clinical Impact of Flow Adjusted Transmitral Pressure Gradient After Surgical Annuloplasty for Functional Mitral Regurgitation

Downsizing of mitral annulus due to mitral annuloplasty for ischemic functional mitral regurgitation (FMR) raises a new issue, functional mitral stenosis (FMS), defined as a decline of mitral hemodynamics. However, common mitral hemodynamic parameters are influenced by transmitral flow, therefore, the clinical impacts are still controversial. The aim of this study is to seek mitral hemodynamic indices (including transmitlra pressure gradient [TMPG] adjusted by left ventricular stroke volume [LVSV]) relevant to the mid-term outcomes after annuloplasty for ischemic functional mitral regurgitation (FMR). This study is a retrospective evaluation of mitral valve hemodynamic status by resting echocardiogram at several weeks after surgery. Eighty-one patients underwent mitral annuloplasty for ischemic FMR between September 2012 and June 2019. Postoperative adverse events occurred in 28 patients (34.6%), and the overall 5-year freedom from adverse events rate was 55.9%. Common mitral hemodynamic parameters were not associated with adverse events, but flow adjusted TMPG can be a correlative factor. By multivariable analysis, postoperative systolic pulmonary artery pressure and peak TMPG/LVSV were detected as independent predictors (adjusted hazard ratio 1.07 and 1.08, P < 0.001 and < 0.001). Additionally, risk stratification by peak TMPG (cut-off: 10 mm Hg) and LVSV (cut-off: 35 mL/m2) reflected the mid-term outcomes, perceptively (P = 0.007). Conventional mitral hemodynamic parameters were not associated with adverse cardiac events after annuloplasty for ischemic FMR. However, flow adjusted TMPG was identfied as an independent predictor, and risk stratification by peak TMPG and LVSV reflected the mid-term outcomes, perceptively.

Ischemic functional mitral regurgitation: from pathophysiological concepts to current treatment options. A systemic review for optimal strategy.

The current treatment of ischemic functional mitral regurgitation (FMR) remains debated due to differences in inclusion criteria of randomized studies and baseline characteristics. Also, the role of left ventricular pathophysiology and the role of subvalvular apparatus have not been thoroughly investigated in recent literature. A literature search was performed from PubMed inception to June 2020. Novel concepts of pathophysiology, such as the proportionate/disproportionate conceptual framework, the role of papillary muscles and left ventricular dysfunction, the impact of myocardial ischemia and revascularization, left ventricular remodeling, and the effect of restrictive annuloplasty or subvalvular procedures have been reviewed. The clinical benefits associated with the use of MitraClip is more evident in patients with disproportionate FMR with greater and sustained left ventricular reverse remodeling. Importantly, in the absence of myocardial revascularization, expansion of myocardial scar tissue and non-perfused areas of ischemic myocardium occur with time, and this impact on outcomes with a longer follow-up period cannot be quantified. In advanced phases of FMR, neither mitral ring annuloplasty nor percutaneous therapies could significantly modify the established pathoanatomic alterations.

Partial Annuloplasty Rings in the Repair of Functional Ischemic Mitral Regurgitation.

BackgroundAcute myocardial infarction (MI) is the leading cause of worldwide cardiac morbidities and mortalities. Mitral regurgitation (MR) is a common complication of MI. The severity of ischemic MR (IMR) can range widely, both clinically and hemodynamically. Mitral valve (MV) repair by lifting annuloplasty is a surgical procedure used to correct the pathology of IMR. The immediate outcomes of this technique have not yet been determined. The present study, therefore, evaluated the immediate results of MV annuloplasty performed to complement MV repair in patients with IMR.MethodologyAll adult patients with IMR who underwent lifting posterior mitral annuloplasty (LPMA) plus concomitant coronary artery bypass grafting (CABG) were included. Immediate outcomes were evaluated by transesophageal color Doppler echocardiography. The frequency of successful outcomes was compared in patients with different baseline characteristics.ResultsPosterior mitral annuloplasty was successful in 93.1% of patients, including in 92.8% of men and 94.1% of women. The percentages of successful immediate outcomes differed significantly in patients with and without diabetes and hypertension, and in patients with two- and three-vessel disease.ConclusionLPMA resulted in a high percentage of successful immediate outcomes in patients with IMR. Further studies should compare rates of immediate, intermediate, and late outcomes of this technique.

Epicardial Posterior Papillary Muscle Repositioning with Mitral Annular Reduction for FIMR Treatment: Initial Ex Vivo Heart Model Study.

High recurrent functional ischemic mitral regurgitation (FIMR) has been observed after annuloplasty. Since annuloplasty alone could not prevent late recurrent FIMR or improve the survival rate after CABG, adjunctive subvalvular opt for better treatment tailored for each individual patient. Ex vivo ovine heart models with annular dilatation and PPM displacement were used for analysis of mitral regurgitation (MR) flow, left ventricular and annular geometry after treatment by mitral annular reduction alone (MA, nMA = 12) or combined with epicardial PPM repositioning (MA+PPM, nMA+PPM=13). MR significantly was reduced from baseline in both the MA (P = .03) and MA+PPM (P = .02) groups, but was not significantly different between the groups. The septo-lateral mitral annular distance decreased after applying both methods (MA group P = .005; MA+PPM group P = .05). The tethering α angle of the APM in the frontal plane significantly increased from baseline in the MA+PPM group (P = .027). Furthermore, the MA+PPM group had a larger APM and PPM α angle in the frontal plane compared with the MA group after reducing the MR (P = .04). There were no statistically significant changes in tethering angles found in the MA group compared with baseline. MR reduction correlated with percentage decrease of septo-lateral mitral annular distance (rs = 0.51, P = .01), the percentage decrease of fibrosa-PPM distance (rs = 0.43, P = .03), and the percentage increase of the PPM anterior displacement (rs = -0.41, P = .04). The decreased tethered angle of the PPM referred to the annulus, and the decreased interpapillary muscles distance suggested the PPM was repositioned inward and toward the septal annulus by the epicardial pushing pad. Epicardial repositioning of the PPM adjunct with mitral annular reduction facilitated leaflet coaptation without the risk of overlying restriction of the mitral annular orifice.

P749 Echocardiographic risk factors of functional ischemic mitral regurgitation in patients with first acute myocardial infarction

Abstract Purpose The aim of this study was to assess the correlation between the size of acute functional ischemic mitral regurgitation (FIMR) and selected left ventricle echocardiography measurements in patients (pts) with first ST-segment elevation myocardial infarction (STEMI) treated with effective primary angioplasty (PCI). Methods We analyzed 1578 consecutive hospitalized pts with STEMI (M-914; 66,4 ± 10,2 years) treated with PCI. The echocardiographic examination was performed at up to 3 days after admission. We assessed the frequency and size of FIMR, left ventricular end diastolic diameter (LVEDd), ejection fraction (EF), wall motion score index (WMSI) and systolic sphericity index (Sls). Effective regurgitation orifice area (EROA) was used for quantitative FIMR assessment (mild: &amp;lt;10 mm², moderate: ≥10 and &amp;lt; 20 mm², severe: ≥ 20mm²). The study population was divided into four groups depending on the size of FIMR. Correlation coefficient was used to determine correlations between data sets. Results We observed mild FIMR in 550 pts (34,9%) - group I, moderate in 356 pts (22,5%) - group II, severe in 57 pts (3,6%) - group III, no FIMR in 615 pts (39%) – group IV. Mean values of selected echocardiographic parameters in each analyzed group are shown in table 1. The positive good correlations between SIs and size of FIMR were found (r = 0,68) as well as weak correlations between LVEDd, WMSI and FIMR (ro = 0,25, ro = 0,34, respectively). The negative weak correlation between EF and size of IMR was present (ro = - 0,34). Conclusions 1. FIMR is a common complication in pts with STEMI treated with PCI. 2. We found a statistically significant correlation between SIs and FIMR severity. Table 1 Group I Group II Group III Group IV p LVEDd (cm) 5,22 ± 0,64 5,42 ± 0,56 5,72 ± 0,64 4,98 ± 0,58 NS EF (%) 48 ± 6 42 ± 8 35 ± 8 51 ± 8 NS WMSI 1,34 ± 0,28 1,42 ± 0,24 1,68 ± 0,32 1,32 ± 0,22 NS SIs 0,22 ± 0,1 0,32 ± 0,1 0,68 ± 0,1 0,18 ± 0,1 0,01 NS - non-significant

1635 Catch me if you can: a rare case of two-staged MitraClip detachment

Abstract Case report A 74-year-old man presented with acute heart failure and chronic obstructive pulmonary disease exacerbation. His medical history revealed: anterior myocardial infarction in 2005, treated with primary PCI of left anterior descending coronary artery followed by triple coronary artery bypass, atrial fibrillation, hypertension, diabetes mellitus and obesity. Transthoracic and transesophageal echocardiography (TEE) showed severe functional ischemic mitral regurgitation (MR) with multiple jets, the main one involving the A2-P2 scallops due to asymmetric tethering of the posterior leaflet. The vena contracta diameter (VC) was 8 mm, the effective regurgitant orifice area (EROA) 0.53 cm². Global left ventricular (LV) function was preserved with inferior-posterior wall akinesis. After "Heart Team" discussion, due to high surgical risk, the patient was referred for percutaneous mitral valve repair (PMVR) using MitraClip (MC) system (Abbott Vascular, Illinois). One clip (MC-XTR) was placed at the A3-P3 segments; subsequently, prior to releasing a second clip (MC-XTR), the first one partially detached from the posterior leaflet (Fig A). A third clip (MC-NTR) was implanted medially. The grasp was challenging but at the end of the procedure, the first clip appeared stable and marked reduction of MR was achieved (Fig B). 7 days later, the patient became symptomatic for resting dyspnea and worsened his clinical status. A control 2D-3D TEE revealed a complete detachment of the first implanted clip, visible distally into the LV, trapped in the mitral valve subchordal apparatus (Fig C). This resulted in massive MR (VC: 12 mm, EROA: 0.91 cm²) with an eccentric posteriorly directed regurgitant jet (Fig D). The patient underwent emergency surgical retrieval of the migrated clip, and removal of the torn mitral valve anterior leaflet. The other two clips were also removed (Fig E), and a bioprosthetic mitral valve was implanted. The procedure was completed uneventfully and the patient is in stable conditions at 2-months follow-up. Discussion The constant stretching and whip effect of the mitral leaflets captured between the clips arms, used in PMVR, can lead to complications. Partial clip detachment is a rare adverse event described in ∼0.7-4.9% of patients within 30 days after MC intervention*. We experienced a two-staged MC detachment that is an even rarer complication and requires emergency surgery. In addition, we highlights the usefulness of 3D TEE for early diagnosis and better imaging characterization in patients who develop complications after MC procedure. No conflict of interest. *Puls M, Lubos E, Boekstegers P, von Bardeleben RS, Ouarrak T, Butter C, Zuern CS, Bekeredjian R, Sievert H, Nickenig G, Eggebrecht H, Senges J, Schillinger W. One-year outcomes and predictors of mortality after MitraClip therapy in contemporary clinical practice: results from German transcatheter mitral valve interventions registry. Eur Heart J 2016;37:703-12. Abstract 1635 Figure.

Five-year clinical outcomes after percutaneous edge-to-edge mitral valve repair: Insights from the multicenter GRASP-IT registry

The Getting Reduction of mitrAl inSufficiency by Percutaneous clip implantation in ITaly (GRASP-IT) is a multicenter registry including 304 consecutive patients undergoing Mitraclip between October 2008 and October 2013 at 4 Italian centers. Primary end point (all-cause mortality) and secondary end point (all-cause mortality or heart failure [HF] hospitalization) were evaluated up to 5 years and between 1 and 5 years. Cumulative incidence of the primary and secondary end points at 1, 2, 3, 4, and 5 years were 15.1%, 26.4%, 35.5%, 42.1%, and 47.3% and 29.1%, 41.7%, 49.8%, 56%, and 62.3%, respectively. Landmark analysis between 1 and 5 years showed an incidence of primary and secondary end point of 37.9% and 46.8%, respectively. Five-year event rates were significantly higher in patients with functional ischemic mitral regurgitation (MR) compared to other etiologies. MR recurrence and left ventricular ejection fraction <30% were associated with an increased risk of both primary and secondary end points. EuroSCORE II >5% was associated with an increased risk of 5-year mortality. Ischemic etiology of MR, baseline serum creatinine >1.5 mg/dL, chronic obstructive pulmonary disease, and previous HF hospitalizations were independent predictors of 5-year secondary end point. At 5-year follow-up after Mitraclip, nearly half of patients died and almost two thirds died or were admitted for HF. MR recurrence, ischemic etiology, high comorbidity burden (ie, EuroSCORE II >5%, chronic obstructive pulmonary disease), and advanced cardiomyopathy (ie, left ventricular ejection fraction <30%, prior HF admission, creatinine >1.5 mg/dL) significantly increase the relative risk of 5-year clinical events.

Predictive impact of previous coronary artery bypass grafting on mortality after MitraClip implantation for ischemic functional mitral regurgitation

BackgroundMany candidates with ischaemic functional mitral regurgitation (FMR) have previously undergone coronary artery bypass grafting (CABG), in which transcatheter mitral valve repair can be reasonable for ameliorating the deteriorated hemodynamic and heart failure symptoms. We sought to elucidate the outcomes of MitraClip (MC) implantation in patients with symptomatic ischaemic FMR after CABG. MethodsWe investigated clinical characteristics, outcomes and predictive impact of previous CABG on mortality in ischaemic FMR patients who underwent MC implantation from two high-volume centres in Germany. ResultsWe enrolled 159 patients who previously underwent CABG. Compared with a reference group that did not previously undergo CABG (n = 182), the cohort consisted of more elderly patients (75.0, standard deviation [SD] 7.7 versus 72.9, SD 9.6 years, p = 0.028), more men (84% vs. 69%, p < 0.001), and reduced tricuspid annular plane systolic excursion (14.0, SD 4.0, vs. 16.6, SD 4.6 mm, p < 0.0001). The CABG group showed similar outcomes regarding procedural success (91% vs. 94%, p = 0.24) and 30-day mortality (5.0% vs. 6.0%, p = 0.68), but worse survival after MC implantation (log-rank p = 0.019, hazard ratio 1.56 [95% confidence interval (CI) 1.08–2.26]). After propensity score matching (n = 224), the hazard ratio was 1.18 [95%CI 0.76–1.84] without statistical significance (p = 0.46). ConclusionsTranscatheter mitral valve repair using the MC is a viable treatment option for patients with symptomatic ischaemic FMR after CABG. Although the baseline characteristics seemed to point to sick patients, CABG itself had only a modest impact on survival.

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.

P2582Impact of left circumflex coronary artery disease on outcomes after successful transcatheter mitral valve repair using the MitraClip for ischaemic functional mitral regurgitation

P2582Impact of left circumflex coronary artery disease on outcomes after successful transcatheter mitral valve repair using the MitraClip for ischaemic functional mitral regurgitation

Application of 3D printing in cardiovascular intervention

This study aims to define the clinical history and significance of mitral leaflet (ML) adaptation in ischemic mitral regurgitation (IMR). Mitral regurgitation (MR) (leaking of left heart valve) frequently complicates myocardial infarction (MI) (heart attack) and is associated with doubled mortality and morbidity. Unfortunately, its mechanism is incompletely understood and treatment options are often limited and ineffective. It has been widely accepted that IMR is purely "functional", because the ML appear grossly normal, but only tethered by left ventricular and annular dilatation, preventing adequate closure. Therefore, contemporary treatment of IMR focus mainly on annular and ventricular remodeling. However, the ML tissues are metabolically active capable of cell activation and matrix proteins production. Recent animal studies has suggested that the ML actively adapt to mechanical stretch by increasing its surface area and thickness, casting doubt on functional IMR being purely "functional". In clinical settings, our understanding of the natural history of ML adaptation is very limited. Its incidence, timing, clinical significance, and interactions with annulus and ventricular remodeling remain undefined. The clinical data has been lacking because imaging techniques were previously unable to assess leaflet surface area in vivo. Recent advance in real-time 3-dimensional echocardiography (RT3DE) has enabled us to assess mitral valve 3D geometry non-invasively, providing a new way to study ML adaptation in clinical settings. We hypothesize that ML adaptation does occur in IMR after MI, attempting to increase in size to compensate for the tethering caused by ventricular and annular dilatation. To test this hypothesis, we will prospectively study 2 groups of patients presenting with MI, one group complicated with IMR, one group without. We will follow them up with serial RT3DE from the acute phase of MI to the chronic phase for 1 year. The 3D geometry of ML, annulus and left ventricle will be analyzed using a novel software developed and validated collaboratively by the Chinese University of Hong Kong and the University of Hong Kong. We will (1) compare the prospective changes of ML geometry between the 2 groups, (2) define the long-term natural history of ML adaptation, (3) explore how it is related to pathogenesis of IMR, and (4) identify potential factor(s) that affect ML adaptation. We believe the results of this project will significantly increase our knowledge on mitral valve adaptation in IMR. Understanding and potentially influencing the adaptive mechanisms will contribute to new, much needed treatment for IMR, a common and often devastating disorder. Researcher ID (E-9217-2013) : http://www.researcherid.com/rid/E-9217-2013

Two-year cardiac mortality after MitraClip treatment of functional mitral regurgitation in ischemic and non-ischemic dilated cardiomyopathy

BackgroundMitraClip implantation has evolved as a new tool for treatment of inoperable or high-risk patients with severe functional mitral regurgitation (FMR) due to dilated cardiomyopathy (DCM). Limited data are available regarding MitraClip outcomes comparing patients with ischemic and non-ischemic DCM. MethodsFrom 2008 to 2016, 314 patients received MitraClip for FMR at four institutions: Brescia, Zurich and Milan. Patients were stratified according to MR aetiology in non-ischemic FMR (n = 99) and ischemic FMR (n = 215). Preoperative risk factors, operative variables and outcomes up to 2-year were evaluated. A multivariable Cox Proportional Hazards survival model with covariate adjustments was used to assess the relationship between FMR aetiology and 2-year cardiac mortality. ResultsAs expected, patients with ischemic FMR had significantly more risk factors and comorbidities. Overall procedural success rate was 80% and in-hospital cardiac mortality was 3% without significant differences between aetiology. Two-year overall (25% vs. 19%, p = 0.574) and cardiac (18% vs. 16%, p = 0.990) mortality rates were comparable. No differences were detected in terms of re-hospitalization rates (32%), LVAD implantation (4.5%) and mitral valve surgery (1%). LVEF ≤ 25%, LVEDV > 216 ml, NT-proBNP ≥ 10.000 pg/ml and AF were the strongest baseline predictors of 2-year cardiac mortality. Greater improvements of 6MWT and NYHA functional class were observed in patients with non-ischemic FMR. ConclusionsThe ischemic or non-ischemic aetiology of DCM did not affect in-hospital and 2-year cardiac mortality after MitraClip in patients with FMR. In case of unfavorable baseline clinical condition, the indication for MitraClip should be carefully weighed in favour of conservative medical therapy alone or left ventricular assist device.

The Impact of Mitral Disease Etiology on Operative Mortality After Mitral Valve Operations

The pathoetiology of mitral regurgitation (MR) has been suggested as a mediator of outcomes after mitral valve (MV) operations, particularly in ischemic functional mitral regurgitation (IMR). This study examined the independent association of MV etiology with mortality. The Society of Thoracic Surgeons Database was utilized to assess all patients undergoing MV replacement or repair from 2011 to 2014. Patients who underwent concomitant surgical ablation, septal defect closure, tricuspid valve repair, or coronary artery bypass grafting were included. All other concomitant operations were excluded, producing a final cohort of 89,085 patients. A hierarchical etiology decision tree was developed to categorize the population into eight etiology groups: endocarditis, reoperation, acute IMR, rheumatic, uncommon etiologies (hypertrophic obstructive cardiomyopathy, trauma, tumor, or congenital), degenerative primary MR, chronic IMR, and pure annular dilatation. The statistical association of etiology with unadjusted and risk-adjusted operative mortality was evaluated by logistic regression and supplemented by sensitivity analyses using established risk models. The decision tree showed that etiology categories appeared clinically aligned with published population distributions, baseline characteristics, and unadjusted outcomes. Unadjusted operative mortality ranged from 1.2% for degenerative MV repair to 15.1% for MV replacement in acute IMR. After risk adjustment, MV etiologies per se exhibited insignificant independent associations with risk-adjusted operative mortality. Mortality after mitral operations is determined primarily by standard clinical risk factors. Mitral etiology does not appear to add independent predictive value.

Fonksiyonel Mitral Yetersizliği Tedavisinde Perkütan Kapak Tamiri Sonrası Kardiyak Resenkronizasyon Tedavisi

We present a case of a 72-year-old female with symptomatic heart failure and ischaemic functional mitral regurgitation (FMR), who underwent a successful percutaneous trans-coronary venous mitral annuloplasty with the Carillon™ system. The procedure resulted in some clinical improvement but patient was still very symptomatic. Six months later, the patient underwent cardiac resynchronisation (CRT) device implantation, resulting in a further improvement in clinical and echo­cardiographic measures of FMR. This case suggests a possible synergistic effect between CRT and percutaneous trans-coronary-venous mitral annuloplasty.

Functional ischemic mitral regurgitation in acute myocardial infarction: Importance of changes in left ventricular shape and regional function

Functional ischemic mitral regurgitation (IMR) is common in patients with ischemic left ventricular dysfunction after myocardial infarction, and significantly worsens prognosis. The aim of this study is to determine the relative importance of the global and regional left ventricular (LV) remodelling in the occurrence of IMR. Eighty-one patients (mean age = 61 ± 11 years) admitted with acute myocardial infarction (AMI) were screened. Patients with atrial fibrillation and organic valvular diseases were excluded from the study. Echocardiography (two-dimensional and Doppler echocardiograms) was performed in the first week after admission. The 81 patients were divided in 2 groups: with IMR (group 1 = 39 patients) and without IMR (group 2 = 42 patients). LV volumes were calculated by apical biplane Simpson's rule. The LV wall-motion score (WMS) index was obtained in a 17-segment model according to established methods. To identify the influence of regional wall-motion impairment for each individual LV segment, the mean WMS was calculated for each segment and compared between the 2 groups. The echocardiographic parameters that were associated with IMR were: LV dilatation and sphericity ( P < 0.0001), reduced ejection fraction ( P < 0.0001), inferior ( P < 0.001) inferolateral ( P = 0.01) and anterolateral ( P = 0.02) asynergy. The results of this study indicate the importance of abnormalities of both LV geometry and regional wall motion in the pathogenesis of IMR after myocardial infarction. Clinically, these findings imply that myocardial salvage by early coronary revascularisation may improve outcome by preserving LV function and decreasing the incidence of IMR.