Effect of Recurrent Mitral Regurgitation Following Degenerative Mitral Valve Repair: Long-Term Analysis of Competing Outcomes

Long-term outcomes of rheumatic mitral valve repair: Is it worthwhile to do it?

AIM

This retrospective study was undertaken to evaluate the long-term outcomes of mitral valve repair in rheumatic patients.

METHODS

From 2003 to 2019, 151 patients (mean age 26.5 ± 14.9 years; 68.9% female) underwent mitral valve repair. Fifty-three (35.1%) had atrial fibrillation, and 79 (52.3%) were in New York Heart Association class III/IV. Pure mitral regurgitation was present in 109 (72.2%) patients, pure stenosis in 9 (6%), and mixed regurgitation and stenosis in 33.

RESULTS

Three (2%) patients died postoperatively and 4 (2.6%) were lost during follow-up. Mean follow-up was 90.5 ± 55.6 months. There were 22 (14.8%) late deaths. Actuarial survival at 5, 10, and 15 years was 90.7% ± 2.5%, 83.5% ± 3.6%, and 76.5 ± 6.1%, respectively. Twelve (8.5%) patients underwent reoperation. Freedom from reoperation at 5, 10, and 15 years was 96.1% ± 1.7%, 89.8% ± 3.2%, and 82.3% ± 6.1%, respectively. Forty-two (29.2%) patients developed recurrent mitral regurgitation. Freedom from recurrence of mitral regurgitation at 5, 10, and 15 years was 70.9% ± 4.3%, 56% ± 5.9%, and 53.3% ± 6.4%, respectively. Eighty-one (56.6%) patients were and free from all events during follow-up. Freedom from all events at 5, 10, and 15 years was 64.8% ± 4.1%, 48.6% ± 5.3%, and 43.7% ± 5.8%, respectively.

CONCLUSIONS

Although rheumatic mitral valve repair is associated with late recurrence of mitral regurgitation, it has benefits in selected patients, especially children and young patients who want to avoid the lifelong risks of anticoagulation. Long-term follow-up is essential in these patients.

Techniques for Mitral Valve Re-repair

The emergence of mitral valve repair as the preferred treatment for severe mitral regurgitation (MR) caused by degenerative disease has been accompanied by an increasing number of valve repair failures seen by surgeons. Consequently, the feasibility of valve re-repair vs valve replacement at the time of reoperation has become a valid clinical consideration. In this report we explore the mechanisms of mitral valve repair failure as well as factors that meaningfully influence the likelihood of a successful re-repair. We provide illustrations of techniques for re-repair that we have used with reliable success, informed by the mechanism of repair failure. Lastly, we share our outcomes for mitral valve re-repair over the last 5 years and discuss our experience using the techniques illustrated in this report.

Predictive Value of Pre-Operative 2D and 3D Transthoracic Echocardiography in Patients Undergoing Mitral Valve Repair: Long Term Follow Up of Mitral Valve Regurgitation Recurrence and Heart Chamber Remodeling

The “ideal” management of asymptomatic severe mitral regurgitation (MR) in valve prolapse (MVP) is still debated. The aims of this study were to identify pre-operatory parameters predictive of residual MR and of early and long-term favorable remodeling after MVP repair. We included 295 patients who underwent MV repair for MVP with pre-operatory two- and three-dimensional transthoracic echocardiography (2DTTE and 3DTTE) and 6-months (6M) and 3-years (3Y) follow-up 2DTTE. MVP was classified by 3DTTE as simple or complex and surgical procedures as simple or complex. Pre-operative echo parameters were compared to post-operative values at 6M and 3Y. Patients were divided into Group 1 (6M-MR < 2) and Group 2 (6M-MR ≥ 2), and predictors of MR ≥ 2 were investigated. MVP was simple in 178/295 pts, and 94% underwent simple procedures, while in only 42/117 (36%) of complex MVP a simple procedure was performed. A significant relation among prolapse anatomy, surgical procedures and residual MR was found. Post-operative MR ≥ 2 was present in 9.8%: complex MVP undergoing complex procedures had twice the percentage of MR ≥ 2 vs. simple MVP and simple procedures. MVP complexity resulted independent predictor of 6M-MR ≥ 2. Favorable cardiac remodeling, initially found in all cases, was maintained only in MR < 2 at 3Y. Pre-operative 3DTTE MVP morphology identifies pts undergoing simple or complex procedures predicting MR recurrence and favorable cardiac remodeling.

Contemporary techniques for mitral valve repair-the Mayo Clinic experience

Mitral valve repair for patients with degenerative or functional mitral valve regurgitation improves symptoms and prognosis, and several techniques have been described. Important principles in operation are simplicity, reproducibility, and durability of repair. At Mayo Clinic, we have operated on more than 6000 patients with degenerative mitral valve disease and valve prolapse, and this review details our approach to mitral valve repair, including robotic and minimally invasive techniques. Most patients with isolated leaflet prolapse can be managed with leaflet plication or triangular resection, and chordal replacement is reserved for repair of anterior leaflet prolapse. Posterior annuloplasty with a standard-sized flexible band is used to reduce annular circumference and improve leaflet coaptation. With these methods, early risk of mortality for mitral valve repair is low in the current era (< 1%), and rate of recurrent valve leakage is 1.5 per 100 patient-years during the first year post-repair and 0.9 per 100 patient-years thereafter. This paper also briefly summarizes important considerations for patients with mitral valve regurgitation and severe calcification, perforations due to endocarditis, and rheumatic heart disease.

Mitral valve repair for degenerative mitral regurgitation in patients with left ventricular systolic dysfunction: early and mid-term outcomes

BACKGROUND

This study aims to evaluate the early and mid-term outcomes of mitral valve repair for degenerative mitral regurgitation (MR) in patients with left ventricular systolic dysfunction.

METHODS

From January 2005 to December 2016, the profiles of patients with degenerative MR who underwent mitral valve repair at our institution were analyzed. Left ventricular systolic dysfunction was defined as an ejection fraction < 60% or left ventricular end-systolic dimension > 40 mm. Finally, 322 patients with left ventricular systolic dysfunction were included in this study. The prognosis of left ventricular function during follow-up was evaluated and preoperative factors associated with deteriorated left ventricular systolic function during follow-up were analyzed.

RESULTS

The in-hospital mortality rate was 1.6%. The rate of eight-year overall survival, freedom from reoperation for mitral valve and freedom from recurrent MR were 96.9, 91.2 and 73.4%, respectively. Intraoperative residual mild MR (hazard ratio 4.82) and an isolated anterior leaflet lesion (hazard ratio 2.48) were independent predictive factors for recurrent MR. During follow-up, 212 patients underwent echocardiography examinations at our institution. Among them, 132 patients had improved left ventricular systolic function, and 80 patients had deteriorated left ventricular systolic. Freedom from recurrent MR was found in 75.9% of the improved left ventricular systolic function group and 56.2% of the deteriorated left ventricular systolic function group (P = 0.047). An age > 50 years (odds ratio 2.40), ejection fraction≤52% (odds ratio 2.79) and left ventricular end-systolic dimension≥45 mm (odds ratio 2.31) were independent risk factors for deteriorated left ventricular systolic function during follow-up.

CONCLUSIONS

Mitral valve repair could be safely performed for degenerative MR in patients with left ventricular systolic dysfunction. Intraoperative residual mild MR and an isolated anterior leaflet lesion were independent predictive factors for recurrent MR. An age > 50 years, ejection fraction≤52% and left ventricular end-systolic dimension≥45 mm were independent risk factors for deteriorated left ventricular systolic function during follow-up.

Surgical treatment of mitral regurgitation

PURPOSE OF REVIEW

Mitral repair is the best treatment for degenerative mitral regurgitation. Many patients are referred too late for optimal outcomes. The US repair vs. replacement rate is only 60-80%, at a time when the inferiority of replacement has been established. Therefore, widely used traditional techniques of repair are being reappraised.

RECENT FINDINGS

Identification of risk factors predictive of poor early and late outcome have improved timing for surgical referral. Composite risk scores have been developed. Novel echocardiographic, cardiac MRI, and molecular level risk factors could improve timing. Analysis of factors contributing to low repair rates is also of critical importance. The role of institutional and surgeon volumes have been identified. More detailed data on the importance of dynamic function of the mitral valve have led to improved repair techniques such as intraoperative simulation of end diastole and early systole, use of expanded polytetrafluoroethylene neochords instead of leaflet resection, and dynamic instead of rigid annuloplasty.

SUMMARY

Our perception of mitral regurgitation has changed from a seemingly simple condition to one of considerable complexity at multiple levels. National guidelines should be studied and followed.

Transcatheter Mitral Valve Replacement With the Transseptal EVOQUE System

OBJECTIVES

The aim of this study was to examine the initial experience with a novel transseptal transcatheter mitral valve replacement (TMVR) system.

BACKGROUND

Transseptal TMVR may offer a less invasive option than surgery for mitral regurgitation (MR) with greater efficacy and fewer anatomic limitations than transcatheter repair.

METHODS

Patients were treated with the EVOQUE TMVR system from September 2018 to October 2019. Key inclusion criteria were moderate or greater MR, New York Heart Association functional class ≥II, and high or prohibitive surgical risk. The primary outcome was technical success, defined by Mitral Valve Academic Research Consortium criteria.

RESULTS

Fourteen patients were treated, all with at least moderate to severe MR. The median age was 84 years, and the median Society of Thoracic Surgeons score was 4.6%. MR was degenerative in 4 (28.6%), functional in 3 (21.4%), and mixed in 7 (50%). Technical success was achieved in 13 patients (92.9%), and 1 patient was converted to surgery. At 30 days there was 1 noncardiovascular mortality (7.1%), 2 strokes (14.3%), no myocardial infarctions, and no rehospitalizations. Two patients (14.3%) underwent paravalvular leak closure. One patient (7.1%) underwent alcohol septal ablation for left ventricular outflow tract obstruction. Including the 2 patients with paravalvular leak closure, MR was mild or less in all implanted patients at 30 days, with no MR in 10 (83.3%). Mean mitral gradient was 5.8 mm Hg (median). New York Heart Association functional class improved to ≤II in 9 patients (81.8%).

CONCLUSIONS

This first-in-human experience has demonstrated the feasibility of the transseptal EVOQUE TMVR system. Further clinical studies are required to establish safety and clinical outcomes.

Cost-effectiveness of coronary artery bypass grafting plus mitral valve repair versus coronary artery bypass grafting alone for moderate ischemic mitral regurgitation

OBJECTIVE

The Cardiothoracic Surgical Trials Network reported that left ventricular reverse remodeling at 2 years did not differ between patients with moderate ischemic mitral regurgitation randomized to coronary artery bypass grafting plus mitral valve repair (n = 150) or coronary artery bypass grafting alone (n = 151). To address health resource use implications, we compared costs and quality-adjusted survival.

METHODS

We used individual patient data from the Cardiothoracic Surgical Trials Network trial on survival, hospitalizations, quality of life, and US hospitalization costs to estimate cumulative costs and quality-adjusted life years. A microsimulation model was developed to extrapolate to 10 years. Bootstrap and deterministic sensitivity analyses were performed to address uncertainty.

RESULTS

In-hospital costs were $59,745 for coronary artery bypass grafting plus mitral valve repair versus $51,326 for coronary artery bypass grafting alone (difference $8419; 95% uncertainty interval, 2259-18,757). Two-year costs were $81,263 versus $67,341 (difference 13,922 [2370 to 28,888]), and quality-adjusted life years were 1.35 versus 1.30 (difference 0.05; -0.04 to 0.14), resulting in an incremental cost-effectiveness ratio of $308,343/quality-adjusted life year for coronary artery bypass grafting plus mitral valve repair. At 10 years, its costs remained higher ($107,733 vs $88,583, difference 19,150 [-3866 to 56,826]) and quality-adjusted life years showed no difference (-0.92 to 0.87), with 5.08 versus 5.08. The likelihood that coronary artery bypass grafting plus mitral valve repair would be considered cost-effective at 10 years based on a cost-effectiveness threshold of $100K/quality-adjusted life year did not exceed 37%. Only when this procedure reduces the death rate by a relative 5% will the incremental cost-effectiveness ratio fall below $100K/quality-adjusted life year.

CONCLUSIONS

The addition of mitral valve repair to coronary artery bypass grafting for patients with moderate ischemic mitral regurgitation is unlikely to be cost-effective. Only if late mortality benefits can be demonstrated will it meet commonly used cost-effectiveness criteria.

Outcomes of Degenerative Mitral Valve Repair Surgery for Anterior, Posterior, and Bileaflet Pathology

BACKGROUND

Degenerative mitral valve disease involving anterior leaflet pathology is considered less favorable regarding durability of surgical repair than isolated posterior leaflet disease. We aimed to compare the outcomes of patients undergoing mitral valve repair for anterior, posterior, and bileaflet pathologies, and to investigate predictors for repair failure.

METHODS

Of the 760 consecutive patients with degenerative leaflet disease who underwent mitral valve repair, 485 (64%) had posterior, 223 (29%) had bileaflet, and 52 (7%) had anterior leaflet pathology. Mean age was 58 ± 12, 54 ± 14, and 58 ± 17 years, respectively (P = .001). Mean follow-up was 67 ± 47 months.

RESULTS

There was no in-hospital or 30-day mortality. Freedom from reoperation was 97%, 95%, and 92%, respectively, and there were 25 (5%), 9 (4%), and 1 (2%) late deaths in the posterior, bileaflet, and anterior groups, respectively (not significant). Late echocardiography revealed that 94%, 97%, and 96% of patients (posterior, bileaflet, and anterior groups respectively) were free from moderate-severe or severe mitral regurgitation (P = .375). Postoperative residual mild mitral regurgitation emerged as the strongest predictor for recurrent mitral regurgitation (grade 3/4) at follow-up (hazard ratio = 2.36; 95% confidence interval, 1.30-4.29; P = .005). Unlike patients with excess mitral tissue, among patients with fibroelastic deficiency or those who underwent major leaflet resection, the use of larger ring annuloplasty was associated with recurrent mitral regurgitation (hazard ratio = 1.31/ring size increment; P < .001).

CONCLUSIONS

Mitral valve repair can be achieved with excellent early and intermediate results across all valve pathologies. Further studies are required to determine the potential long-term impact of the underlying pathology on the rate of recurrent mitral regurgitation.

Two patterns of the “crossed swords sign” for the accurate diagnosis of diverse mitral valve regurgitations

The “crossed swords sign,” demonstrating the divergent jet, is visualized on 2-dimensional color Doppler imaging and indicates complicated mitral regurgitation (MR). We describe the cases of two patients with varying patterns of the crossed swords sign. In the first patient, the crossed swords sign was detected during the holosystolic phase. In the second patient, the direction of the MR jet changed according to the phase of systole: The crossed swords sign was formed by two regurgitation jets during different phases of systole. The crossed swords sign implies two patterns and is useful for the accurate diagnosis of complex MR.

Utility of Cardiac CT for Preoperative Evaluation of Mitral Regurgitation: Morphological Evaluation of Mitral Valve and Prediction of Valve Replacement

OBJECTIVE

We aimed to investigate the diagnostic accuracy of cardiac computed tomography (CT) for the detection of mitral valve (MV) prolapse in mitral regurgitation (MR) with surgical findings as the standard reference, and to assess the predictability of MV replacement based on morphologic CT findings.

MATERIALS AND METHODS

A total of 156 patients who had undergone preoperative cardiac CT and subsequently received MV surgery due to severe MR were retrospectively enrolled. Non-repairable MV was defined when at least one of the following conditions was met: 1) anterior leaflet prolapse, 2) bi-leaflet prolapse, or 3) valve morphology (leaflet thickening, calcification, or mitral annular calcification [MAC]). Diagnostic performance of CT for the detection of the prolapsed segment was assessed with surgical findings as the standard reference. Logistic regression analysis was performed to evaluate the value of CT findings to predict actual valve replacement.

RESULTS

During surgery, MV prolapse was identified in 72.1%. The sensitivity, specificity, and diagnostic accuracy for the detection of MV prolapse were 99.1%, 81.4%, and 94.2%, respectively, per patient. One-hundred eighteen patients (75.6%) underwent MV repair and the remaining 38 patients received MV replacement. Bi-leaflet prolapse and valve morphology were independent predictors of valve replacement after adjusting for clinical variables (adjusted odds ratio, [OR] 8.63 for bi-leaflet prolapse; OR, 4.14 for leaflet thickening; and OR, 5.37 for leaflet calcium score > 5.6; p < 0.05).

CONCLUSION

Cardiac CT can have high diagnostic performance for detecting the prolapsed segment of the MV and predictability of valve replacement before surgery. Bi-leaflet prolapse and valve morphology, such as leaflet thickening, or calcification or MAC, are the most important predictors of valve replacement.

An 86-Year-Old Female with Mitral Regurgitation and Significant Pectus Excavatum

Background  We report the case of minimally invasive mitral valve repair in an 86-year-old female with symptomatic structural mitral regurgitation and severe pectus excavatum.

Case Description  The case summarizes four areas of repetitive heart team discussions. First, should an 86-year-old patient still be treated invasively? Second, if so, should treatment be interventional or surgical? Third, if surgical, should we replace or repair at that age and fourth which surgical access is best with respect to her chest deformation?

Conclusion  We chose to surgically repair the valve using a minimally invasive approach. The patient was extubated 3 hours after surgery and discharged after 7 days.

Isolated Mitral Valve Repair in Patients with Reduced Left Ventricular Ejection Fraction

Purpose: This study aims to analyze the clinical outcomes after isolated mitral valve (MV) repair in patients with reduced left ventricular ejection fraction (LVEF <50%) with focus on perioperative characteristics, survival, and freedom from reoperations.

Methods: Between 1997 and 2015, 557 patients with reduced LVEF (age: 62.8 ± 11.7 years, male: 320) underwent MV repair for symptomatic mitral regurgitation (MR). Etiologies were dilated non-ischemic cardiomyopathy and ischemic cardiomyopathy in 487 (87.4%) and 70 (12.6%) patients, respectively; these were classified into three different subgroups: LVEF 40%–49% (group 1), 30%–39% (group 2), and <30% (group 3).

Results: Overall, 294, 145, and 118 patients had an LVEF of 40%–49%, 30%–39%, and <30%, respectively. Logistic EuroSCORE was significantly higher (P <0.001) as the LVEF worsened. The survival analysis for groups 1–3, respectively, revealed the following: 30-day mortality: 1.4%, 3.4%, and 7.6% (P <0.001); 1-year survival: 93.9%, 89.4%, and 82% (P <0.001); 5-year survival: 81.2%, 75.2%, and 58% (P <0.001).

Conclusion: MV repair in patients with impaired LVEF could be performed safely with good clinical short- and mid-term outcome. Nevertheless, reduced preoperative LVEF correlates with worse perioperative and long-term survival.

Impact of abrupt versus gradual correction of mitral and tricuspid regurgitation: a modelling study

AIMS

Correction of mitral and/or tricuspid regurgitation (MR, TR) frequently leads to poor outcomes in the days following intervention. We sought to understand how abrupt correction of MR and TR affects ventricular load and to investigate if gradual correction is beneficial.

METHODS AND RESULTS

MR and TR were simulated using the CircAdapt cardiovascular system model with effective regurgitant orifice (ERO) areas of 0.5 cm2 and 0.7 cm2. Ventricular and atrial contractility reductions to 40% of normal and pulmonary hypertension were simulated. Abrupt and gradual ERO closure were simulated with homeostatic regulation of blood pressure and volume. Abrupt correction of MR increased left and right ventricular fibre stress by 40% and 15%, respectively, whereas TR correction increased left and right ventricular fibre stress by 26% and 19%, respectively. This spike was followed by a rapid drop in fibre stress. Myocardial dysfunction prolonged the spike but reduced its amplitude. Right ventricular fibre stress increased more with pulmonary hypertension and TR. Gradual correction demonstrated no spike in tissue load.

CONCLUSIONS

Simulations demonstrated that abrupt ERO closure creates a transient increase in ventricular load that is prolonged by worsened myocardial condition and exacerbated by pulmonary hypertension. Gradual closure of the ERO abolishes this spike and merits clinical investigation.

The impact of intraoperative residual mild regurgitation after repair of degenerative mitral regurgitation

OBJECTIVES

During degenerative mitral repair, surgeons must decide if further repair is warranted for residual mild mitral regurgitation. We examined the incidence of mild mitral regurgitation, late echocardiographic and clinical outcomes, and influence of surgical experience in decision making.

METHODS

From April 2004 to June 2018, 1155 of 1195 patients with pure degenerative disease underwent repair (97% repair rate). Propensity score matching was performed between patients with trace/no mitral regurgitation and patients with mild residual mitral regurgitation. Late echocardiographic outcome and freedom from reoperation were compared using competing-risks models. A comparison of outcomes of the referent surgeon (89.8% of repairs) with all other surgeons was performed.

RESULTS

Mild mitral regurgitation was present in 73 patients (6%). Propensity score-matched analyses compared 69 patients with mild mitral regurgitation with 198 patients without mitral regurgitation. Late moderate or greater mitral regurgitation was higher in those with mild mitral regurgitation than in those with no mitral regurgitation (17% vs 7%, P = .033), as was late moderate-severe or greater mitral regurgitation (6% vs 1%, P = .016). Ten-year freedom from reoperation was low in both groups (99.5% no vs 96.9% mild; P = .10). The referent surgeon had fewer patients with mild residual mitral regurgitation (6% vs 11%, P = .027) and less progression of mitral regurgitation compared with other surgeons (late moderate or greater mitral regurgitation 6% vs 15%, P = .002).

CONCLUSIONS

Residual mild mitral regurgitation was uncommon, and late progression to moderate or greater mitral regurgitation was rare and never led to late mitral reoperation. Experienced surgeons may be better able to determine repairs likely to remain stable, and most mild residual mitral regurgitation does not require re-repair.

Numerical Simulations of MitraClip Placement: Clinical Implications

Mitral regurgitation (MR) is the most common type of valvular heart disease in patients over the age of 75 in the US. Despite the prevalence of mitral regurgitation in the elderly population, however, almost half of patients identified with moderate-severe MR are turned down for traditional open heart surgery due to frailty and other existing co-morbidities. MitraClip (MC) is a recent percutaneous approach to treat mitral regurgitation by placement of MC in the center of the mitral valve to reduce MR. There are currently no computational simulations to elucidate the role of MC on both the fluid and solid mechanics of the mitral valve. Here, we use the Smoothed Particle Hydrodynamics (SPH) approach to study various positional placements of the MC in the mitral valve and its impact on reducing MR. SPH is a particle based (meshless) approach that handles flow through narrow regions quite efficiently. Fluid and surrounding anatomical structure interactions is handled via contact and hence can be used for studying fluid-structure interaction problems such as blood flow with surrounding tissues/structure. This method is available as part of the Abaqus/Explicit solver. Regurgitation was initiated by removing targeted chordae tendineae that are attached to specified leaflets of the mitral valve and, subsequently, MC implants are placed in various locations, starting from the region near where the chordae tendineae were removed and moving away from the location towards the center of the valve. The MC implant location closest to where the chordae tendineae were removed showed the least amount of residual MR post-clip implantation amongst all other locations of MC implant considered. These findings have important implications for strategic placement of the MC depending on the etiology of MR to optimize clinical outcome.

Functional and Degenerative Mitral Regurgitation: One Ring Fits All?

BACKGROUND

Three-dimensional saddle-shaped annuloplasty rings have been shown to create a larger surface of leaflet coaptation in mitral valve repair (MVR) for functional mitral regurgitation (FMR) and degenerative mitral regurgitation (DMR) which may increase repair durability. For the first time, this study reports mid-term results after MVR for DMR and FMR using a rigid three-dimensional ring (Profile 3D, Medtronic).

METHODS

Between June 2009 and June 2012, 369 patients with DMR (n = 326) or FMR (n = 43) underwent MVR (mean age 62.3 ± 12.6 years). A total of 205 patients (55.6%) underwent isolated MVR and 164 patients (44.4%) a combined procedure. Follow-up examinations were performed in 94.9% (mean 4.9 ± 0.9 years). Echocardiographic assessment was complete in 93.2% (mean 4.3 ± 1.2 years).

RESULTS

The 30-day mortality was 1.5% (5/326) for DMR (1.5% for isolated and 1.6% for combined procedures) and 9.3% (4/43) for FMR (0% for isolated and 10.5% for combined procedures). Survival at 6 years was 92.1 ± 1.9% for DMR (92.9 ± 2.6% for isolated and 90.7 ± 2.7% for combined procedures) and 66.4 ± 7.9% for FMR (80.0 ± 17.9% for isolated and 63.7 ± 8.9% for combined procedures). Cumulative risk for mitral valve-related reoperation at 6 years was 0% for FMR and 7.1 ± 1.5% for DMR. At echocardiographic follow-up, one patient presented with mitral regurgitation (MR) more than moderate. The only predictor of recurrent MR after MVR for DMR was residual mild MR at discharge.

CONCLUSION

Repair of FMR with the three-dimensional Profile 3D annuloplasty ring shows excellent mid-term results with regard to recurrence of MR. In cases of DMR, the results are conforming to the current literature.

Elevated Mitral Valve Pressure Gradient Is Predictive of Long-Term Outcome After Percutaneous Edge-to-Edge Mitral Valve Repair in Patients With Degenerative Mitral Regurgitation ( MR ), But Not in Functional MR

Background This study analyzed the effects on long-term outcome of residual mitral regurgitation ( MR ) and mean mitral valve pressure gradient ( MVPG ) after percutaneous edge-to-edge mitral valve repair using the MitraClip system. Methods and Results Two hundred fifty-five patients who underwent percutaneous edge-to-edge mitral valve repair were analyzed. Kaplan-Meier and Cox regression analyses were performed to evaluate the impact of residual MR and MVPG on clinical outcome. A combined clinical end point (all-cause mortality, MV surgery, redo procedure, implantation of a left ventricular assist device) was used. After percutaneous edge-to-edge mitral valve repair, mean MVPG increased from 1.6±1.0 to 3.1±1.5 mm Hg ( P<0.001). Reduction of MR severity to ≤2+ postintervention was achieved in 98.4% of all patients. In the overall patient cohort, residual MR was predictive of the combined end point while elevated MVPG >4.4 mm Hg was not according to Kaplan-Meier and Cox regression analyses. We then analyzed the cohort with degenerative and that with functional MR separately to account for these different entities. In the cohort with degenerative MR , elevated MVPG was associated with increased occurrence of the primary end point, whereas this was not observed in the cohort with functional MR . Conclusions MVPG >4.4 mm Hg after MitraClip implantation was predictive of clinical outcome in the patient cohort with degenerative MR . In the patient cohort with functional MR , MVPG >4.4 mm Hg was not associated with increased clinical events.

Anatomy of mitral annulus insights from non-invasive imaging techniques

The mitral annulus (MA) is not a continuous ring of connective tissue from which are suspended mitral leaflets. Instead, it is a much more complex structure made up of a mix of fibrous, muscular, and adipose tissues. MA is a key structure in any type of mitral valve repair and recently it has been targeted for transcutaneous devices. Thus, a deep understanding of MA anatomy has never been more important. Traditionally, cardiac anatomy has been described using anatomic specimens. Currently, sophisticated non-invasive techniques allow imaging of MA with a richness of anatomical details unimaginable only two decades ago. The aim of this review is to provide a better understanding of the peculiar aspects of MA as they are revealed through these imaging techniques and discuss clinical implications related to this complex structure.

Can We Predict Failure of Mitral Valve Repair?

Objective: To identify echocardiographic and surgical risk factors for failure after mitral valve repair. Methods: We identified a total of 77 consecutive patients from our institutional mitral valve surgery database who required redo mitral valve surgery due to recurrence of mitral regurgitation after primary mitral valve repair. A control group of 138 patients who had a stable echocardiographic long-term result was included based on propensity score matching. Systematic analysis of echocardiographic parameters was performed before primary surgery; after mitral valve repair and prior to redo surgery. Risk factor analysis was performed using multivariate Cox regression model. Results: Redo surgery was associated with the presence of pulmonary hypertension ≥ 50 mmHg (p = 0.02), a mean transmitral gradient > 5 mmHg (p = 0.001), left ventricular ejection fraction ≤ 45% (p = 0.05) before surgery and mitral regurgitation ≥moderate at time of discharge (p = 0.002) in the whole cohort. Patients with functional mitral valve regurgitation had a higher tendency to undergo redo surgery if preoperative left ventricular end-diastolic diameter exceeded 65 mm (p = 0.043) and if postoperative tenting height exceeded 6 mm (p = 0.018). Low ejection fraction was not significantly associated with the need for redo mitral valve surgery in the functional subgroup. Conclusions: Recurrent mitral regurgitation is still a valuable problem and is associated with relevant perioperative mortality. Patients with severe mitral regurgitation should undergo early mitral valve repair surgery as long as systolic pulmonary artery pressure is low, left ventricular ejection fraction is preserved, and LVEED is deceeds 65 mm.

Mitral Valve Repair Rate at a Veterans Affairs Hospital Utilizing a Multidisciplinary Heart Team

Between 2000 and 2008, the mitral valve (MV) repair rate in patients with severe mitral regurgitation at our low-volume Veterans Affairs hospital was 21%. After instituting a multidisciplinary valve team in 2009, we determined whether this rate increased and characterized the outcomes of patients with degenerative disease. We retrospectively reviewed data from 103 MV operations performed at our hospital between 1/2009 and 8/2016. MV pathology was categorized as degenerative, rheumatic, endocarditis, ischemic, hypertrophic cardiomyopathy, or failed prior MV repair. The surgical techniques used for MV repair were reviewed. For the patients with degenerative disease who underwent MV repair, we assessed leaflet involvement and postoperative valve function. For the full cohort, the MV repair rate was 67% and the 30-day mortality rate was 0.97%. Of the 74 patients with degenerative disease, 64 (86.5%) underwent MV repair (none required reoperation). For these patients, the MV repair rate was significantly higher when the surgical approach was sternotomy rather than minimally invasive right minithoracotomy (92.5% vs 71.4%, P = 0.03). After MV repair, 95.3% of the degenerative disease patients had mild or less mitral regurgitation; median echocardiography follow-up time was 555 days. Anatomic features associated with a reduced MV repair rate in patients with degenerative disease were dystrophic leaflet calcification and severe mitral annular calcification. In an institution with a low volume of MV operations, preoperative surgical planning with a multidisciplinary valve team was associated with improved MV repair rates and excellent repair quality in patients with degenerative valve disease.

Transcatheter or surgical repair for degenerative mitral regurgitation in elderly patients: A propensity-weighted analysis

OBJECTIVE

To compare the outcomes of MitraClip and surgical mitral repair in low-intermediate risk elderly patients affected by degenerative mitral regurgitation (DMR).

METHODS

We retrospectively selected patients aged ≥75 years, with Society of Thoracic Surgeons Predicted Risk Of Mortality (STS-PROM) <8%, submitted to MitraClip (n = 100) or isolated surgical repair (n = 206) for DMR at 2 centers between January 2005 and May 2017. To adjust for baseline imbalances, we used a propensity score model for average treatment effect on survival.

RESULTS

After weighting, MitraClip showed fewer postoperative complications (P < .05) but increased residual mitral regurgitation (MR) ≥2 (27.0% vs 2.8%, P < .001) compared with surgery. One-year survival was greater after MitraClip compared with surgery (97.6% vs 95.3%, hazard ratio [HR], 0.09; confidence interval [CI], 0.02-0.37, P = .001), whereas 5-year survival was lower (34.5% vs 82.2% respectively, HR, 4.12; CI, 2.31-7.34, P < .001). Greater STS-PROM (HR, 1.18; CI, 1.12-1.24, P < .001) and MR ≥3+ recurrence (HR, 2.18; CI, 1.07-4.48, P = .033) were associated with reduced survival. 5-year MR ≥3+ was more frequent after MitraClip compared with surgery: 36.9% versus 3.9%, odds ratio, 11.4; CI, 4.40-29.68, P < .001.

CONCLUSIONS

In elderly patients affected by DMR and STS-PROM <8%, the average effect of MitraClip resulted in lower acute postoperative complications and improved 1-year survival compared with surgery. However, MitraClip was associated with greater MR recurrence and reduced survival beyond 1 year. Long-term survival was impaired by patients' greater risk profile and MR recurrence. Early results are promising, but in the setting of operable patients with life expectancy beyond 1 year, the quality bar for transcatheter mitral repair needs to be raised.

Strategy-specific durability of mitral valve repair through the video-assisted right minithoracotomy approach

AIMS

We sought to analyze the early and follow-up results of minimally invasive video-assisted mitral valve repair. With particular focus on degenerative disease, results were stratified according to type of lesion, strategy of repair and surgical technique.

METHODS

We retrospectively built a database over 241 patients who received mitral repair for severe regurgitation through right minithoracotomy in the 2009-17 period. Cause was degenerative in 92.1%, restrictive in 5.8% and mixed in the remainders. Clinical and echocardiographic follow-up (98.7% complete, average duration 2.9 years ± 1.4) was obtained through contact of in-house and territorial cardiologists. Recurrent mitral regurgitation at follow-up was defined as being at least mild-to-moderate (2+).

RESULTS

Operative mortality was 1.7%, and related to the technique in one case. Five-year actuarial survival was 95% ± 2; there was no valve-related death and one reoperation. At follow-up, we observed eight cases of 2+ regurgitation and one instance of 4+ regurgitation (4-year actuarial freedom: 92% ± 4). Freedom from recurrent regurgitation was significantly lower in the 'restrictive' subgroup vs. the 'degenerative' subgroup (P = 0.02); no statistically significant difference in freedom from recurrence was observed among patients who received mitral repair using a 'resect' vs. 'nonresection' strategy (P = 0.46), and in those who received the Totally Endoscopic technique (endoaortic balloon occlusion, no costal spreading) vs. controls (external aortic clamp, costal spreading) (P = 0.98).

CONCLUSION

Durability of minimally invasive mitral repair is optimal. Nonresection repair techniques are at least noninferior to previous approaches based on leaflet resection.

Comparison of Outcomes of Mitral Valve Repair for Leaflet Prolapse with Advanced versus Mild/Moderate Myxomatous Degeneration

There is limited information on long-term outcomes of mitral valve repair for mitral regurgitation (MR) caused by different degrees of myxomatous degeneration. The aim of this study was to compare the surgical results of patients with advanced and mild/moderate myxomatous mitral valve degeneration (MVD). We identified 130 patients (25 advanced and 105 mild/moderate MVD patients) who underwent mitral valve repair for MR and were pathologically diagnosed as myxomatous degeneration. Follow-up was 100% complete (mean length, 5.1 ± 1.8 years). Survival differed significantly between the advanced and mild/moderate MVD groups (76.0 ± 9.7% versus 95.0 ± 5.4% at 8 years, P < 0.001). The univariate predictors of mortality were advanced myxomatous degeneration, recurrent MR, and early series (surgeries before 2011). The mild/moderate MVD group had higher freedom from a moderate or severe MR rate compared with the advanced MVD group (77.4 ± 4.5% versus 50.5 ± 10.2% at 7 years, P = 0.003). Multivariable Cox analysis revealed advanced myxomatous degeneration and residual MR as independent predictors of recurrent moderate or severe MR. A total of 25 patients (19.2%) had persistent atrial fibrillation (AF) after repair. In multivariate analysis, advanced myxomatous degeneration was found to be an independent predictor of postoperative persistent AF.In conclusion, the long-term outcomes of mitral valve repair in patients with advanced MVD are poorer than in those with mild/moderate MVD. Advanced myxomatous degeneration is an independent predictor of recurrent moderate or severe MR and postoperative persistent AF in MVD patients performing repair, which deserves more attention before and after surgery.

Transcatheter mitral valve chord repair

The field of mitral valve disease diagnosis and management is rapidly evolving. New understanding of pathophysiology and improvements in the adoption of sophisticated multimodality imaging modalities have led to early diagnosis and to more complex treatment. The most common cause of mitral regurgitation (MR) in the western world is in the primary alteration of the valve, which leads to degenerative leaflet prolapse due to chordal elongation or rupture and annular dilatation. Untreated, significant MR has a negative impact prognosis, leading to reduction of survival. In the setting of degenerative MR, surgical repair currently represents the standard of care. Treatment of asymptomatic patients with severe MR in the Valve Center of Excellence, in which successful repair reaches more than 95% and surgical mortality less than 1%, symbolizes the direction for the next years. Transcatheter mitral valve repair with different devices, more recently the chordal replacement ones, is providing good outcomes and became a therapeutic option in high-risk patients with degenerative MR. In the future, more advances are expected from further development of interventional techniques, careful evaluation and better patient selection. This review will focus on long-term surgical outcomes of mitral valve repair with artificial chordae and on the emerging transcatheter chordal repair devices as therapeutic options for degenerative MR patients.

Long-Term Results Following Repair for Degenerative Mitral Regurgitation - Analysis of Factors Influencing Durability

BACKGROUND

The majority of patients with degenerative mitral regurgitation (DMR) are amenable to reconstructive procedures. There is debate regarding factors that influence long-term durability with respect to repair technique, valve remodelling and progressive myxomatous change.

METHODS

A total of 685 patients with DMR underwent mitral valve repair by a single surgeon between 1991 and 2011 with follow-up completed at 31 December 2016. Repair rate for patients undergoing surgery for DMR was over 90%. Mean age was 64 years (18-89) with 66.2% male, 47% NYHA class III-IV, and 20% had permanent atrial fibrillation (PAF). Major associated procedures were performed in 28% of patients (189); including coronary artery bypass graft (CABG) (127), aortic valve replacement (15), aortic root surgery (3) and tricuspid valve annuloplasty (61).

RESULTS

Operative mortality (≤30 days) occurred in four patients (0.58%). At 20 years, survival was 58%, freedom from reoperation was 90% and freedom from reoperation and non-operated recurrent MR >2+ (relapse) was 78%. Factors influencing survival were advancing age, left ventricular (LV) dysfunction (ejection fraction <60% or end systolic dimension >40mm), New York Heart Association (NYHA) III-IV and PAF. Predictors of relapse were the degree of residual intraoperative mitral regurgitation (p<0.001), anterior leaflet prolapse (p<0.001) and the addition of a sliding annuloplasty in isolated posterior leaflet repair (p=0.023). The majority of reoperations were for technical issues related to the original repair. A competent valve at 6 months to 3 years postoperatively predicted an excellent long-term result.

CONCLUSION

The great majority of degenerative mitral valves are repairable regardless of age with excellent long-term results achievable following surgery. Survival is reduced by significant symptoms, LV dysfunction and preoperative PAF. Repair is best performed before these features develop. Durability is largely dependent on the technical performance of the repair and degree of residual MR on the post-pump transoesophageal echocardiogram. We recommend surgery should be performed by surgeons specialising and skilled in mitral valve repair.

Benefits of Early Surgery on Clinical Outcomes After Degenerative Mitral Valve Repair

BACKGROUND

This study aimed to evaluate the clinical trends of mitral valve repair for degenerative mitral regurgitation and the benefit of early surgical intervention on repair durability in a high-volume center.

METHODS

From January 2003 to December 2015, 1,903 consecutive patients with severe degenerative mitral regurgitation underwent mitral valve repair at our institution. The timing of surgical intervention was evaluated by guideline-related indications including symptoms, atrial fibrillation, left ventricular dysfunction, and pulmonary hypertension. Clinical outcomes and risk factors for recurrent mitral regurgitation were analyzed.

RESULTS

Over 13 years from 2003 to 2015, trends of preoperative characteristics demonstrated that the proportion of asymptomatic patients substantially increased. The 8-year overall survival, freedom from reoperation for mitral valve, and freedom from recurrent mitral regurgitation were 96%, 96%, and 85%, respectively. Ejection fraction less than 60%, left ventricular end-diastolic dimension greater than 60 mm, isolated anterior leaflet lesion, and intraoperative mild residual mitral regurgitation were independent predictive factors for recurrent mitral regurgitation. The incidence of recurrent mitral regurgitation was significantly lower in the early intervention group (3% versus 18%, p < 0.01). In subgroup analysis of asymptomatic patients, the incidence of recurrent mitral regurgitation was significantly lower in patients without guideline-related indications (3% versus 31%, p < 0.0001).

CONCLUSIONS

Early surgical intervention for severe degenerative mitral regurgitation before symptoms, atrial fibrillation, and ventricular dysfunction are associated with excellent clinical outcomes. Besides complexity of leaflet lesion and repair quality, surgical timing also significantly affects repair durability. Early surgical intervention should therefore be recommended to reduce recurrent mitral regurgitation.

Residual Mitral Regurgitation After Repair for Posterior Leaflet Prolapse-Importance of Preoperative Anterior Leaflet Tethering

Background

Carpentier's techniques for degenerative posterior mitral leaflet prolapse have been established with excellent long‐term results reported. However, residual mitral regurgitation (MR) occasionally occurs even after a straightforward repair, though the involved mechanisms are not fully understood. We sought to identify specific preoperative echocardiographic findings associated with residual MR after a posterior mitral leaflet repair.

Methods and Results

We retrospectively studied 117 consecutive patients who underwent a primary mitral valve repair for isolated posterior mitral leaflet prolapse including a preoperative 3‐dimensional transesophageal echocardiography examination. Twelve had residual MR after the initial repair, of whom 7 required a corrective second pump run, 4 underwent conversion to mitral valve replacement, and 1 developed moderate MR within 1 month. Their preoperative parameters were compared with those of 105 patients who had an uneventful mitral valve repair. There were no hospital deaths. Multivariate analysis identified preoperative anterior mitral leaflet tethering angle as a significant predictor for residual MR (odds ratio, 6.82; 95% confidence interval, 1.8–33.8; P=0.0049). Receiver operator characteristics curve analysis revealed a cut‐off value of 24.3° (area under the curve, 0.77), indicating that anterior mitral leaflet angle predicts residual MR. In multivariate regression analysis, smaller anteroposterior mitral annular diameter (P<0.001) and lower left ventricular ejection fraction (P=0.002) were significantly associated with higher anterior mitral leaflet angle, whereas left ventricular and left atrial dimension had no significant correlation.

Conclusions

Anterior mitral leaflet tethering in cases of posterior mitral leaflet prolapse has an adverse impact on early results following mitral valve repair. The findings of preoperative 3‐dimensional transesophageal echocardiography are important for consideration of a careful surgical strategy.