Undersized Annuloplasty Research Articles

Posterior Leaflet Detachment, Augmentation, and Reconstruction for Treatment of Functional Mitral Valve Regurgitation

Functional mitral regurgitation caused posterior leaflet tethering and central malcoaptation treated utilizing undersized annuloplasty alone is associated with high rates of early failure. We report the technical steps necessary for near complete near complete detachment, augmentation and reconstruction of a thin and diminutive posterior mitral leaflet to reproducibly re-establish normal mitral leaflet coaptation and eliminate functional MR.

Surgical management of moderate ischemic mitral valve regurgitation: Where do we stand?

Ischemic mitral regurgitation (IMR) represents a common complication after myocardial infarction. The valve is anatomically normal and the incompetence is the result of papillary muscles displacement and annular dilatation, causing leaflets tethering. Functionally the leaflets present a restricted systolic motion due to tethering forces that displaces the coaptation surface toward the left ventricle apex. The patients present poor left ventricular function at the time of surgery and the severity of the mitral regurgitation increases the risk of mortality. Currently there is general agreement to treat surgically severe IMR nevertheless strong evidences for patient with moderate insufficiency remains poor and proper treatment debated. The most effective surgical approach for the treatment of IMR remains debated. Some authors demonstrated that coronary artery bypass graft (CABG) alone is beneficial in patients with IMR. Conversely, in most patients, moderate IMR will persist or worsen after CABG alone which translate in higher long-term mortality as a function of residual mitral regurgitation severity. A probable reason for this unclear surgical management of functional MR is due to the contemporary suboptimal results of reparative techniques. The standard surgical treatment of chronic IMR is CABG associated with undersized annuloplasty using complete ring. Though, the recurrence of mitral regurgitation remains high (> 30%) because of continous left ventricle remodeling. To get better long term results, in the last decade, several subvalvular procedures in adjunct to mitral anuloplasty have been developed. Among them, surgical papillary muscle relocation represents the most appreciated option capable to restore normal left ventricle geometry. In the next future new preoperative predictors of increased mitral regurgitation recurrence are certainly needed to find an individual time period of treatment in each patient with moderate IMR.

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Resultados de la reparación mitral en función de la etiología: 15 años de seguimiento

BackgroundEtiology and other factors may influence the outcomes of mitral valve repair. We have analyzed survival and durability in a variety of etiologies. Material and Methods406 patients underwent mitral valve repair (1997–2011) with ages between 19–84 years. 156 were females (38.4%). 57.1% patients were in NYHA class III-IV. 5 groups were considered: degenerative (group-D), 203; ischemic (group-I), 90; functional (non-ischemic) (group-F), 19; rheumatic (group-R), 61 and endocarditis (group-E), 33 patients. Undersized annuloplasty was used in ischemic and functional groups. Quadrangular resection and neochordal repair were predominant in case of degenerative etiology whereas a variety of resective and reconstructive techniques were used in rheumatic and endocarditis groups. Results30-day mortality was 4.4%: 3.4%, 4.4%, 0%, 6.6% and 10% in respective groups. 5 and 10-year survival: 86±1% and 70±4%. Long-term mortality was higher in groups F and I (31.6% and 20%) compared with 12.3%, 11.5% and 13.3% in groups D, R and E. Group-D had higher durability and freedom from grade 3–4/4 mitral regurgitation than non-degenerative groups: 86±2 vs 84±2% (p=0.46) at 5 years and 82±3 vs 54±1% (p=0.02) at later follow-up. Group-R was associated with recurrent grade-3 and grade-4 mitral regurgitation (OR: 1.98, 95%-CI: 1.01–3.89; p=0.05 and OR: 3.31, 95%-CI: 1.17–9.32; p=0.02). 14 patients underwent mitral valve replacement: 3, 1, 1, 6 and 3. ConclusionsThe outcomes of mitral valve repair were successful. Survival, recurrence rate and reoperation were excellent in group-D. Rheumatic regurgitation had shorter durability and functional mitral regurgitation had lower survival.

Surgical treatment for functional mitral regurgitation secondary to dilated cardiomyopathy: Current options and future trends

There is an increasing number of patients with mitral regurgitation secondary to dilated cardiomyopathy. Recent data suggest that mitral regurgitation (MR) can be surgically corrected in heart failure with symptomatic improvements and favourable reverse left ventricular remodeling. However, several questions remain to be answered, regarding the optimal management of functional mitral regurgitation, the correct timing of surgery and the choice of the surgical technique to perform in patients affected by dilated cardiomyopathy. In the setting of ischemic chronic cardiomyopathy, data derived from the recent literature suggest that concomitant severe ischemic MR should be addressed during CABG to improve survival and quality of life. Most surgeons perform concomitant CABG and mitral valve surgery in patients with ischemic chronic cardiomyopathy and moderate to severe MR. In the setting of chronic dilated cardiomyopathy, most clinicians would agree that correction of severe MR in heart failure is warranted, mostly due to a symptomatic benefit and reduction of number of re-hospitalizations. Moreover, reverse ventricular remodeling has been demonstrated with undersized annuloplasty rings and correction of MR: this could lead to improved contractility, reduction in left ventricular end-diastolic and end-systolic volumes, and finally to improved NYHA functional class. Recent large studies suggest that patients undergoing mitral valve repair had improved perioperative survival, shorter length of stay, and improved long-term survival than those undergoing mitral valve replacement because the preservation of the subvalvular apparatus seems to result in superior left ventricular remodelling and in greater improvement in NYHA class. In the near future, data from multi-institutional, randomized prospective trials will help to elucidate many of the questions and concerns regarding repair of severe functional mitral regurgitation. Finally, technology applied to heart surgery is continually evolving and will allow more exciting cellular and novel device therapies for the treatment of functional mitral regurgitation secondary to dilated cardiomyopathy.

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Annuloplasty Ring Dehiscence in Ischemic Mitral Regurgitation

A 75-year-old woman described having shortness of breath. Four months earlier she had undergone coronary artery bypass grafting and undersized annuloplasty for treatment of ischemic mitral regurgitation (IMR). Real-time three-dimensional echocardiography revealed annuloplasty ring (AR) dehiscence (Fig 1A) from the posterior annulus (PA) and recurrent IMR (Fig 1B). Often the degree of annular undersizing necessary to restore valve competence in IMR is substantial and predisposes to ring dehiscence.

Reply to Tavlasoglu et al.

We are happy to reply to the letter from Tavlasoglu et al. [1] to further elucidate our position on transcatheter mitral valve therapies. Dr Tavlasoglu has questioned the title of our recently published paper [2]: in the author’s opinion, mitral repair for functional mitral regurgitation (FMR) is not confined to undersized annuloplasty alone. Undersized annuloplasty is universally considered the standard procedure for treating FMR. We do agree that there are other options, but these are neither proven nor standardized. This was the reason for restricting the inclusion criteria to this technique alone, with the aim of comparing a new therapy (MitraClip) to the most proven surgical therapy (undersized annuloplasty [3]). Tavlasoglu et al. question the value of the EVEREST trial in supporting clinical decision-making. The EVEREST addressed low-risk surgical candidates, mostly with degenerative aetiology [4]. Currently, most patients undergoing the MitraClip procedure are non-surgical candidates with FMR. The surgical patients were very carefully selected, to keep the risk profile low and preserve the chance of clinical success. On the contrary, patients who underwent MitraClip had a higher risk profile. This message should be not missed: patients treated by transcatheter interventions today are patients who have been denied surgery. Transcatheter interventions offer the unique opportunity of staging interventions to mitigate risk. However, most of the associated procedures performed in the surgical cohort, although being recognized as risk factors for early mortality, are associated with long-term benefit. Therefore, if the comparison could be unfair against surgery in the early term, it is in favour as far as the longer follow-up is considered. In addition, we are reluctant to believe that associated procedures like revascularization have a negative impact on early outcomes in patients with FMR. In fact, the guidelines support associated procedures with a higher level of evidence when compared with isolated mitral valve surgery [5]. There are other important issues related to the amount of reverse remodelling achievable by MitraClip when compared with surgery. Future studies should address this issue in a more effective way. Regarding the durability of the technique, surgical experience has demonstrated that annuloplasty improves durability [6], and we expect transcatheter techniques to implement annuloplasty. Finally, in the opinion of Tavlasoglu et al., the MitraClip should not be considered an alternative option in FMR. Two European Society of Cardiology guidelines committees had a different opinion when they included the MitraClip as a treatment option in high-risk and inoperable patients with FMR and severe symptoms despite optimal medical therapy [5]. The guidelines suggest a class IIb indication (evidence C). This reflects the scarcity of data supporting stronger statements. However, it should be recalled that surgery in isolated FMR has exactly the same level of evidence and class of indication as the MitraClip, reflecting the similar lack of evidence. Our opinion is that we, surgeons, should focus on collecting evidence to further support surgical techniques before rejecting novel therapies, and be more open to incorporating technological innovations in our practice to be able to judge their value based on direct experience.

Comprehensive Annular and Subvalvular Repair of Chronic Ischemic Mitral Regurgitation Improves Long-Term Results With the Least Ventricular Remodeling

Undersized ring annuloplasty for ischemic mitral regurgitation (MR) is associated with variable results and >30% MR recurrence. We tested whether subvalvular repair by severing second-order mitral chordae can improve annuloplasty by reducing papillary muscle tethering. Posterolateral myocardial infarction known to produce chronic remodeling and MR was created in 28 sheep. At 3 months, sheep were randomized to sham surgery versus isolated undersized annuloplasty versus isolated bileaflet chordal cutting versus the combined therapy (n=7 each). At baseline, chronic myocardial infarction (3 months), and euthanasia (6.6 months), we measured left ventricular (LV) volumes and ejection fraction, wall motion score index, MR regurgitation fraction and vena contracta, mitral annulus area, and posterior leaflet restriction angle (posterior leaflet to mitral annulus area) by 2-dimensional and 3-dimensional echocardiography. All groups were comparable at baseline and chronic myocardial infarction, with mild to moderate MR (MR vena contracta, 4.6±0.1 mm; MR regurgitation fraction, 24.2±2.9%) and mitral annulus dilatation (P<0.01). At euthanasia, MR progressed to moderate to severe in controls but decreased to trace with ring plus chordal cutting versus trace to mild with chordal cutting alone versus mild to moderate with ring alone (MR vena contracta, 5.9±1.1 mm in controls, 0.5±0.08 with both, 1.0±0.3 with chordal cutting alone, 2.0±0.4 with ring alone; P<0.01). In addition, LV end-systolic volume increased by 108% in controls versus 28% with ring plus chordal cutting, less than with each intervention alone (P<0.01). In multivariate analysis, LV end-systolic volume and mitral annulus area most strongly predicted MR (r(2)=0.82, P<0.01). Comprehensive annular and subvalvular repair improves long-term reduction of both chronic ischemic MR and LV remodeling without decreasing global or segmental LV function at follow-up.

Posterior Leaflet Augmentation in Ischemic Mitral Regurgitation Increases Leaflet Coaptation and Mobility

Restoring leaflet coaptation is the primary objective in repair of ischemic mitral regurgitation (IMR). The common practice of placing an undersized annuloplasty ring partially achieves this goal by correcting annular dilation; however, annular reduction has been demonstrated to exacerbate posterior leaflet tethering. Using a sheep model of IMR, we tested the hypothesis that posterior leaflet augmentation (PLA) combined with standard annuloplasty sizing increases leaflet coaptation more effectively than undersized annuloplasty alone. Eight weeks after posterobasal myocardial infarction, 15 sheep with 2+ or greater IMR underwent annuloplasty with either a 24-mm annuloplasty ring (24-mm group, n = 5), 30-mm ring (30-mm group, n = 5), or 30-mm ring with concomitant augmentation of the posterior leaflet (PLA group, n = 5). Using three-dimensional echocardiography, postrepair coaptation zone and posterior leaflet mobility were assessed. Leaflet coaptation length after repair was greater in the PLA group (4.1 ± 0.3 mm) and the 24-mm group (3.8 ± 0.5 mm) as compared with the 30-mm group (2.7 ± 0.6 mm, p < 0.01). Leaflet coaptation area was significantly greater in the PLA group (121.5 ± 6.6 mm(2)) as compared with the 30-mm group (77.5 ± 17.0 mm(2)) or the 24-mm group (92.5 ± 17.9 mm(2), p < 0.01). Posterior leaflet mobility was significantly greater in the PLA group as compared with the 30-mm group or the 24-mm group. Posterior leaflet augmentation combined with standard-sized annuloplasty enhances leaflet coaptation more effectively than either standard-sized annuloplasty or undersized annuloplasty alone. Increased leaflet coaptation after PLA provides redundancy to IMR repair, and may decrease incidence of both recurrent IMR and mitral stenosis.

Reply to Kestelli et al.

We would like to thank Dr Mert Kestelli et al. [1] for their interest in our study [2] and for the issues they addressed in their letter. We agree with them that the reduction in the septal–lateral dimension of the mitral annulus provided by undersized ring annuloplasty may contribute to the decrease in the left ventricular (LV) volume after surgery. However, this effect alone is not sufficient to explain the occurrence of reverse LV remodelling which is a multifactorial process still rather difficult to predict as demonstrated by the fact that it could not be demonstrated in 43% of the patients in whom this end-point was assessed. As clearly described in Results section of our manuscript, associate procedures such as myocardial revascularization, successful ablation of atrial fibrillation and cardiac resynchronization therapy were not positively related to the occurrence of reverse remodelling. For some of them, such as cardiac resynchronization therapy, this lack of effect could probably be due to the small number of patients treated. The patients with preoperative asymmetric tethering were 18 (24%) and had a significantly higher recurrence rate of mitral regurgitation (MR) compared with those with preoperative symmetric tethering. In our opinion, this represents a very important finding that should be taken into consideration when selecting patients for whom an undersized annuloplasty is evaluated as a possible therapeutic option. According to our results, in the presence of prevalent restricted motion of the posterior leaflet, additional surgical techniques addressing the subvalvular apparatus or mitral replacement rather than repair should be considered. With regard to the recurrence of MR following undersized annuloplasty with a GeoForm ring, 9% of our patients had moderate-to-severe (3+/4+) mitral insufficiency at follow-up (and not 16% of them, a percentage that also includes the cases with 2+/4+ MR). This rate is comparable with that reported with other types of ring [3] and is likely to further decrease if preoperative predictors of repair failure identified so far will be taken into account during the decision-making process. However, we strongly disagree with Kestelli et al. about the use of flexible rings in functional MR since it has been demonstrated in several observational and randomized studies that they are associated with a higher rate of annular re-dilatation and MR recurrence compared with the rigid ones [4, 5], and their use should therefore be discouraged in this setting.

Assessment of Mitral Valve Complex by Three-Dimensional Echocardiography: Therapeutic Strategy for Functional Mitral Regurgitation

The mitral valve complex is consisted of annulus, leaflets, chordae tendineae, papillary muscle (PMs) and surrounding left ventricle. Functional mitral regurgitation (MR) results from left ventricular remodeling such as dilatation or distortion, which displaces the PMs and then tethers the mitral leaflets, restricting leaflet coaptation. Undersized annuloplasty, which has been widely accepted as a simple and effective procedure for functional MR, sometimes worsens the tethering of posterior leaflet and induces recurrent MR. In order to overcome such problems, several additional procedures to the simple annuloplasty have been produced. Three dimensional echocardiography plays an essential role to understand the geometry of mitral valve complex and contributes greatly to decision making of the surgical strategy in functional MR and its postoperative assessment.

Comparison of small and enlarged aortic roots

manuscript, associated procedures such as myocardial revascularization, successful ablation of atrial fibrillation and cardiac resynchronization therapy were not positively related to the occurrence of reverse remodelling. For some of them, such as cardiac resynchronization therapy, this lack of effect could probably be due to the small number of patients treated. There were 18 (24%) patients with preoperative asymmetric tethering who had a significantly higher recurrence rate of mitral regurgitation (MR) compared with those with preoperative symmetric tethering. In our opinion, this represents a very important finding that should be taken into consideration when selecting patients for whom an undersized annuloplasty is evaluated as a possible therapeutic option. According to our results, in the presence of prevalent restricted motion of the posterior leaflet, additional surgical techniques addressing the subvalvular apparatus or mitral replacement rather than repair should be considered. With regard to the recurrence of MR following undersized annuloplasty with a GeoForm ring, 9% of our patients had moderate-to-severe (3+/4+) mitral insufficiency at follow-up (and not 16% of them, a percentage that also includes the cases with 2+/4+ MR). This rate is comparable with that reported with other types of ring [3] and is likely to further decrease if preoperative predictors of repair failure identified so far are taken into account during the decision-making process. However, we strongly disagree with Kestelli et al. about the use of flexible rings in functional MR since it has been demonstrated in several observational and randomized studies that they are associated with a higher rate of annular redilatation and MR recurrence compared with the rigid ones [4, 5], and their use should therefore be discouraged in this setting.

Posterior leaflet augmentation improves leaflet tethering in repair of ischemic mitral regurgitation

Ischemic mitral regurgitation results from annular dilatation, leaflet tethering and leaflet flattening. Undersized annuloplasty corrects annular dilatation but worsens leaflet tethering and flattening. This exacerbation of abnormal leaflet geometry may contribute to poor repair results for ischemic mitral regurgitation (IMR). Using a sheep model of IMR, we hypothesized that posterior leaflet augmentation and less-extreme annular undersizing would relieve tethering and increase leaflet curvature. Eight weeks after posterolateral infarct, 10 sheep with ≥ 2+ IMR underwent either a 24-mm planar ring annuloplasty (n = 5) or a 30-mm planar ring annuloplasty with concomitant posterior leaflet augmentation (n = 5). Real-time three-dimensional echocardiography allowed measurement of indices of leaflet curvature and tethering before and after annuloplasty. Comparing pre- and post-repair values in the P1, P2, and P3 leaflet regions, undersized 24-mm ring annuloplasty made no significant difference to mean septolateral curvature (0.23-0.26, 0.33-0.29, and 0.27-0.37 cm(-1), respectively), whereas leaflet augmentation in combination with a 30-mm ring annuloplasty increased septolateral curvature (P1 0.30-1.02, P2 0.31-1.23, and P3 0.35-0.84 cm(-1), p-values<0.05). The mean tethering angle formed between the annular plane and the posterior leaflet increased in all three posterior regions for the 24-mm ring group (P1 12-23°, P2 26-31°, and P3 16-25°), but decreased in all regions for the group undergoing leaflet augmentation (P1 +5 to -6°, P2 +13 to -13°, P3 +16-15°, all p-values < 0.05). Undersized annuloplasty exacerbates leaflet tethering. Posterior leaflet augmentation with less severe annular reduction increases leaflet curvature and decreases tethering; this technique more completely addresses the pathogenic mechanism of IMR and may improve repair durability.

Impact of increased transmitral gradients after undersized annuloplasty for chronic ischemic mitral regurgitation

BackgroundRecent studies have demonstrated that undersized ring mitral annuloplasty (URMA) for chronic ischemic mitral regurgitation (CIMR) can induce iatrogenic mitral stenosis. The impact of this functional mitral stenosis on clinical and echocardiographic results is not well established. Methods125 consecutive URMA for CIMR were dichotomized according to postoperative mean trans-mitral gradient (Δp) into Group A (61 patients, >5mmHg) and Group B (64 patients, ≤5mmHg). Echocardiographic, clinical and functional outcomes were prospectively recorded and compared. ResultsThere were no hospital deaths. Intensive-care and hospital length of stay were comparable in the 2 groups (p=N.S.). Twenty-three months of actuarial survival was 73.2±8.0%, without inter-group differences (log-rank p=0.627), actuarial freedom from congestive heart failure was 71.4±5.6%, freedom from hospitalization was 59.8±7.7%, without inter-group differences (p=0.497 and 0.393 respectively), and actuarial freedom from recurrent CIMR was 62.7±10.4%, without group-difference (p=0.259), respectively. Both groups showed progressive improvement of NYHA (Time p=0.0001), with reduced diuretics (p=0.0001), and without inter-group differences (Group⁎Time p=0.894 and 0.397 respectively). Both groups showed a constant improvement of left ventricular end-systolic diameters, ejection fraction, CIMR-grade, tricuspid insufficiency grading, indexed left ventricular mass, systolic pulmonary arterial pressure, and tricuspid annular plane systolic excursion (Time p=0.0001 for all), without intergroup differences (p=N.S. for all). However, left ventricular end-diastolic diameters were better remodeled in Group A (Group⁎Time p=0.037), together with a higher mean trans-mitral Δp and a lower coaptation depth (Group⁎Time p=0.0001 and 0.05 respectively). Left atrial diameter was ameliorated in Group B, but remained unchanged in Group A (p=0.168). ConclusionsURMA cures CIMR. The induction of mild mitral stenosis did not affect clinical, functional and echocardiographic outcomes.

Mitral valve repair for functional mitral regurgitation: is annuloplasty alone enough?

To outline indications and contraindications to mitral valve surgery in the clinical context of dilated cardiomyopathy and the surgical principles to follow in performing an undersized annuloplasty. Moreover, we will describe the characteristics of the patients for whom an annuloplasty alone is unlikely to provide an effective result and for whom,therefore, some other procedures or mitral valve replacement should be preferred. In functional mitral regurgitation, competence of the mitral valve can be restored by using a restrictive annuloplasty. This procedure leads to symptomatic improvement and reverse left ventricular remodeling in a substantial proportion of patients. However, the failure rate of undersized annuloplasty is still high and is mainly due to inappropriate patient selection and to technical issues that have been progressively identified. In the treatment of functional mitral regurgitation, annuloplasty alone should only be carried out in the early phase of the disease before the occurrence of advanced left ventricular remodeling and echocardiographic predictors of unfavorable outcome should be taken into account. Under certain circumstances, surgery should include additional procedures apart from annuloplasty to enhance the durability of the repair. Mitral valve replacement should be considered when unsatisfactory results are expected with mitral valve repair due to advanced left ventricular remodeling and long-lasting heart failure.

173 Surgery of chronic functional mitral regurgitation : post operative outcomes and respective results of undersizing annuloplasty and valve replacement

Dismal prognostic impact of functional mitral regurgitation (MR) in dilated cardiomyopathy has been well established. However, indication of surgery and its modalities (undersizing annuloplastie (UA) vs mitral valve replacement (MVR)) are controversial. 1/Immediate and late post-operative outcomes in patients operated for severe functional MR 2/Analysis of respective result of UA and MVR. Inclusion criteria : 1/Symptomatic severe functional MR 2/Ischemic or non ischemic cardiomyopathy with LVEF<45%. Primary endpoints: 1/In-hospital mortality 2/Late mortality. Secondary endpoints: 1/evolution of LVEF 2/recurrence of MR. 33 patients(age = 65±10, LVEF = 36 ± 6%, ERO= 41 ± 17 mm 2 ). Surgery : 11 UA and 22 MVR. No per-operative death. In-hospital mortality: 6% in total population, 9% in UA group, 4.5% in MVR group (p = NS). Late postoperative mortality: 3 years survival: 77% in total population, 88% in UA group and 71% in MVR group (p> 0.99). By multivariable analysis, only age (1.3 [1,1-1,5], p = 0001) and LV end systolic diameter(1.16 [1, 05-1.29], p=0005) independently predicted late mortality whereas type of surgery did not(0.6 [0,1-3,9], p = 0.6). Evolution of the LVEF: LVEF did not change after surgery in the MVR group (36 ± 6% vs 36 ± 7%, p = 0.1) but tended to decrease in the UA group (36 ± 6% vs 30 ± 12%, p = 0.06) MR recurrence: No recurrence in the MVR group whereas 80% recurrence in the UA group (ERO= 21±6 mm 2 ). functional MR surgery can be performed with relatively low operative risk, including in most severe patients, and acceptable mid-term result. MVR is a reasonable option with similar early results than UA but without exposing patient to MR recurrence risk particularly high in our series.

Baseline left ventricular function and surgical annular stiffening to predict outcome and reverse left ventricular remodeling after undersized annuloplasty for intermediate-degree ischemic mitral regurgitation

We sought to identify determinants of clinical and functional outcome after myocardial revascularization and associated undersized annuloplasty in patients with intermediate-degree ischemic mitral regurgitation. Fifty-seven patients with 2+ or 3+ ischemic mitral regurgitation underwent coronary bypass surgery and implantation of undersized semirigid or flexible complete ring or autologous pericardial band and were followed up to 8.6 years. Operative mortality was 5%. Baseline left ventricular end-systolic volume index, the strongest multivariable predictor of early postoperative outcome, was correlated with end-systolic volume index (P < .001, R(2) = 0.67) and ejection fraction (P < .001, R(2) = 0.40) after repair. More compromised ejection fraction and end-systolic volume index predicted comparatively greater early functional improvement but higher residual postoperative end-systolic volume index (P < .01). Cox multivariable analysis identified wall motion as the best baseline predictor of late death and heart failure and regional inferoposterior wall motion as the strongest predictor of recurrent mitral regurgitation (P < or = .01). More rigid annuloplasty carried a higher probability of functional recovery in terms of ejection fraction, wall motion, and the occurrence and earlier timing of left ventricular reverse remodeling, expressed by different degrees of end-systolic volume index reduction (P < .001, hazard ratio >6). Combination of undersized mitral annuloplasty and coronary revascularization presents low operative mortality and determines left ventricular unloading in patients with intermediate-degree ischemic mitral regurgitation. Global and regional wall motion are powerful predictors of late outcome. Stiffer mitral annular repair promotes functional recovery and predicts higher probability and earlier timing of reverse remodeling.

Insights on left ventricular and valvular mechanisms of recurrent ischemic mitral regurgitation after restrictive annuloplasty and coronary artery bypass grafting

We investigated leaflet and subvalvular configurations to identify mechanisms leading to recurrent mitral regurgitation after combined undersized mitral annuloplasty and coronary artery bypass and to preoperatively recognize patients who are unlikely to benefit from this approach. Among 261 subjects with chronic ischemic mitral regurgitation undergoing undersized annuloplasty and coronary bypass surgery at one institution between September 2001 and September 2007, 31 were excluded: 4 had intraoperative annuloplasty failure, 12 showed residual regurgitation, and 15 had incomplete echocardiograms available. The study population consisted of 230 patients who were divided into 2 groups: patients without (group 1, n = 176) or with (group 2, n = 54) late recurrent mitral regurgitation. Fifty healthy subjects were used as control subjects. Serial echocardiographic analysis was performed preoperatively, at discharge, and at follow-up appointments (early: median, 6 months [interquartile range, 5-6 months; late: median, 33 months [interquartile range, 17-51 months]). Subjects with late regurgitation had preoperatively more symmetric tethering (P < .001), more accentuated anterior mitral leaflet tethering (P < .001), and more restricted anterior leaflet excursion (P = .003) than patients in group 1. Postoperatively, tethering of the posterior leaflet increased (P < .001) and was predominant in both groups, whereas tethering of the anterior leaflet was reduced at discharge (P = .01 and P = .03, respectively), remaining constant afterward. Multivariable analysis showed an anterior tethering angle of 39.5 degrees or greater (P < .001), an anterior/posterior tethering angle ratio of 0.76 or greater (P < .001), an anterior leaflet excursion angle of 35 degrees or less (P = .001), and a coaptation height of 11 mm or greater (P = .04) to be predictors of recurrent mitral regurgitation. Preoperative symmetric tethering with anterior mitral leaflet predominance was strongly associated with recurrence of mitral regurgitation. Measures of leaflet tethering resulted in fundamental findings to identify ischemic patients who can really benefit from restrictive annuloplasty. Further larger studies are necessary to confirm our results.

New Surgical Procedure for Ischemic/Functional Mitral Regurgitation: Mitral Complex Remodeling

Although numerous surgical techniques have been developed for ischemic/functional mitral regurgitation, none has clearly improved patient outcome. We report the clinical application of a new mitral complex remodeling procedure for ischemic/functional mitral regurgitation that allows comprehensive remodeling of the entire mitral complex. The mitral complex remodeling procedure consists of three major concepts: division and reconstruction of secondary chords, undersized annuloplasty, and bilateral papillary muscle relocation.