Mid-term clinical outcomes of totally endoscopic repair for mitral regurgitation in Barlow's disease.

OBJECTIVE: This study aimed to confirm the safety and feasibility of totally endoscopic repair for mitral regurgitation (MR) in Barlow's disease. METHODS: From June 2018 to December 2022, 21 consecutive Barlow's disease patients (aged 33 ± 12 years; 57.1% male) underwent totally endoscopic mitral valve (MV) repair with leaflets folding, multiple artificial chordae implantation and ring annuloplasty. The safety and feasibility of this technique was evaluated by its mid-term clinical outcomes. RESULTS: There was no operative death or complications. The mean cardiopulmonary bypass (CPB) time was 190 ± 41 (128-267) min, and the aortic cross-clamp time was 145 ± 32 (66-200) min. The average number of artificial chordae implantation was 2.9 ± 0.7 (1-4) pairs. The mean MV coaptation length was 1.4 ± 0.3 (0.8-1.8) cm, and the median transvalvular gradient was 1 [interquartile range (IQR), 1-2] mmHg. During a median follow-up time of 24 (IQR, 10-38) months, all patients showed persistent effective valve function with no significant MR or systolic anterior motion. CONCLUSIONS: Totally endoscopic repair was a safe, effective, and reproducible procedure with satisfied mid-term clinical outcomes for MR in Barlow's disease. However, further randomized and long-term follow-up studies were warranted to determine its clinical effects.

Interpapillary muscle distance independently predicts recurrent mitral regurgitation.

OBJECTIVE: Ischaemic secondary mitral regurgitation (ISMR) after surgery is due to the displacement of papillary muscles resulting from progressive enlargement of the left ventricle end-diastolic diameter (LVEDD). Our aim was to prove that if the interpapillary muscle distance (IPMD) is surgically stabilized, an increase in LVEDD will not lead to a recurrence of ischaemic mitral regurgitation (MR). METHODS: Ninety-six patients with ISMR, who underwent surgical revascularisation and annuloplasty, were randomly assigned in a 1:1 ratio to undergo papillary muscle approximation (PMA). At the 5-year follow-up, we assessed the correlation between PMA and echocardiographic improvements, the effect size of PMA on echocardiographic improvements, and a prediction model for recurrent MR using inferential tree analysis. RESULTS: There was a significant correlation between PMA and enhancements in both the α and ß angles (Spearman's rho > 0.7, p < 0.01). The α angle represents the angle between the annular plane and either the A2 annular-coaptation line or the P2 annular-coaptation line. The ß angle indicates the angle between the annular plane and either the A2 annular-leaflet tip line or the P2 annular-leaflet tip line. PMA led to substantial improvements in LVEDD, tenting area, α and ß angles, with a large effect size (Hedge's g ≥ 8, 95% CI ORs ≠ 1). The most reliable predictor of recurrent MR grade was the interpapillary distance, as only patients with an interpapillary distance greater than 40 mm developed ≥ 3 + grade MR. For patients with an IPMD of 40 mm or less, the best predictor of recurrent MR grade was LVEDD. Among the patients, only those with LVEDD greater than 62 mm showed moderate (2+) MR, while only those with LVEDD less than or equal to 62 mm had absent to mild (1+) MR. CONCLUSION: Prediction of recurrent ischaemic MR is not independent of progressive LVEDD increase. PMA-based surgical procedure stabilises IPMD.

The study of loading mode with in-vitro fatigue testing for mitral annuloplasty ring.

To maintain the physiological dynamics of the mitral annulus, mitral annuloplasty rings (MAR) must be flexible. Enhanced flexibility implies decreased resistance to fatigue and potential for fatigue fracture. This study established new methods to test the flexible fatigue life of MAR in-vitro using numerical analysis; the purpose is that the fatigue test could reflect the real stress distribution in-vivo. Based on the conventional test methods (C1, D1), this paper presents a novel test method (C2, D2). Four testing methods for open-end annuloplasty rings (C1, C2) and closed-end annuloplasty rings (D1, D2) were modelled and their stress distribution calculated by finite element analysis. The mean absolute error (Χ) and the Pearson correlation coefficient (Φ) were used to quantify the difference in stress distribution between the loading modes in-vivo and in-vitro. For closed-end annuloplasty rings, the novel test method (D2) is not obvious better than conventional test methods(D1) in duplicating the stress distribution (ΦD1 = 0.88 vs ΦD2 = 0.92). However, the maximum values of stress in the novel test method are closer to the maximum value of stress under in-vivo loading (ΧD1 = 5.2Mpa vs ΧD2 = 4.4Mpa). For open-end annuloplasty rings, the novel test method(C2) is obviously superior to the conventional test method(C1) in duplicating both the stress distribution and the stress peak values of the in-vivo loading (ΦC1 = 0.22 vs ΦC2 = 0.98; ΧC1 = 59.1Mpa vs ΧC2 = 11.0Mpa). The in-vitro loading methods described in this article more closely approximated in-vivo conditions compared to traditional methods. They are simpler to operate, more efficient and can help manufacturers expedite new product development, assist regulatory agencies with product quality oversight.

Mitral valve leaflet blood cyst treated with minimally invasive approach: a case report and review of literature.

INTRODUCTION: Cardiac blood cyst is a very rare benign tumor of the heart in adults. Though it is very common in the first half year of life, it regresses with time and its occurrence is very rare in children older than six months and in adults. Until now less than 100 valvular blood cyst cases have been reported in adults. CASE PRESENTATION: We present a case of a 66-year-old male who presented to us with exertional chest tightness, shortness of breath, and right leg weakness for two weeks. He was diagnosed with a cardiac mass two months ago in another hospital. The physical examination was unremarkable. Abdominal ultrasound showed a cyst in the liver and left kidney. Echocardiography showed a mass-occupying lesion of a cystic nature in the mitral valve with moderate mitral regurgitation. Based on echocardiography findings and computed tomography report, the preliminary diagnosis of mitral valve cystic tumor was made. The patient underwent minimally invasive resection of the cyst. The posterior mitral cusp was repaired and a mitral annuloplasty ring was placed. The postoperative recovery was uneventful. The histopathology report confirmed the diagnosis of a cardiac blood cyst. The patient was followed up for six months without any complications. This case is presented to enrich the medical literature on the cardiac blood cyst. CONCLUSION: Although a cardiac blood cyst is a rare entity in adults, it still should be considered in the differential diagnosis of cardiac tumors. Because the natural history and hemodynamic effects are very diverse, large symptomatic cardiac blood cysts, especially in the left heart should be resected to avoid complications.

Respect Versus Resect Approaches for Mitral Valve Repair: A Meta-Analysis of Reconstructed Time-to-Event Data.

Mitral valve repair (MVr) has been associated with superior long-term survival and freedom from valve-related complications compared with mitral valve replacement for primary mitral regurgitation (MR). The 2 main approaches for MVr are chordal replacement ("respect approach") and leaflet resection ("resect approach"). We performed a systematic review and a meta-analysis using 3 search databases to compare the long-term end points between both approaches. The primary end point was long-term survival. The secondary end points were long-term MR recurrence and reoperation. After reconstruction of time-to-event data for the individual survival analysis, pooled Kaplan-Meier curves for the end points were generated. A total of 14 studies (5,565 patients) were included in the analysis. The respect approach was associated with superior survival compared with the resect approach in the overall sample (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.56 to 0.96, p = 0.024, n = 3,901 patients) but not in the risk-adjusted sample (HR 1.00, 95% CI 0.55 to 1.82, p = 0.991, n = 620 patients). There was no difference between the approaches in the rate of MR recurrence in the overall sample (HR 1.39, 95% CI 0.92 to 2.08, p = 0.116, n = 1,882 patients) or in the risk-adjusted sample (HR 1.62, 95% CI 0.76 to 3.47, p = 0.211, n = 288 patients). The data for reoperation were only available in the overall sample and did not reveal a difference (HR 0.92, 95% CI 0.62 to 1.35, p = 0.663, n = 3,505 patients). In conclusion, the current evidence suggests no difference in long-term mortality, MR recurrence, or reoperation between the resect and respect approaches for MVr after adjusting for patient risk factors. More long-term follow-up data are warranted.

Simplified Tool for Sizing in Minimally Invasive Mitral Annuloplasty: A Homemade Technique.

Currently, minimally invasive cardiac surgery (MICS) has been developing and has been largely approved for mitral valve surgery. The more development of MICS, the more the entire surgical setup needs to be appropriate. We developed a homemade tool for mitral annular sizing that is simple and fits the mini surgical access. It is a plastic-based foldable paper that can be easily inserted through the minithoracotomy, using a surgical forceps.

Subannular repair in secondary mitral regurgitation with restricted leaflet motion during systole.

OBJECTIVE: Ventricular secondary mitral regurgitation (SMR) (Carpentier type IIIb) results from left ventricular (LV) remodelling, displacement of papillary muscles and tethering of mitral leaflets. The most appropriate treatment approach remains controversial. We aimed to assess the safety and efficacy of standardised relocation of both papillary muscles (subannular repair) at 1-year follow-up (FU). METHODS: REFORM-MR (Reform-Mitral Regurgitation) is a prospective, multicentre registry that enrolled consecutive patients with ventricular SMR (Carpentier type IIIb) undergoing standardised subannular mitral valve (MV) repair in combination with annuloplasty at five sites in Germany. Here, we report survival, freedom from recurrence of MR >2+, freedom from major adverse cardiac and cerebrovascular events (MACCEs), including cardiovascular death, myocardial infarction, stroke, MV reintervention and echocardiographic parameters of residual leaflet tethering at 1-year FU. RESULTS: A total of 94 patients (69.1% male) with a mean age of 65.1±9.7 years met the inclusion criteria. Advanced LV dysfunction (mean left ventricular ejection fraction 36.4±10.5%) and severe LV dilatation (mean left ventricular end-diastolic diameter 61.0±9.3 mm) resulted in severe mitral leaflet tethering (mean tenting height 10.6±3.0 mm) and an elevated mean EURO Score II of 4.8±4.6 prior to surgery. Subannular repair was successfully performed in all patients, without operative mortality or complications. One-year survival was 95.5%. At 12 months, a durable reduction of mitral leaflet tethering resulted in a low rate (4.2%) of recurrent MR >2+. In addition to a significant improvement in New York Heart Association (NYHA) class (22.4% patients in NYHA III/IV vs 64.5% patients at baseline, p<0.001), freedom from MACCE was observed in 91.1% of patients. CONCLUSIONS: Our study demonstrates the safety and feasibility of standardised subannular repair to treat ventricular SMR (Carpentier type IIIb) in a multicentre setting. By addressing mitral leaflet tethering, papillary muscle relocation results in very satisfactory 1-year outcomes and has the potential to durably restore MV geometry; nevertheless, long-term FU is mandatory. TRIAL REGISTRATION NUMBER: NCT03470155.

Image-based ring size prediction for mitral valve repair.

OBJECTIVES: Annuloplasty rings are routinely used in mitral valve repair (MVr). However, accurate annuloplasty ring size selection is essential to obtain a favourable outcome. Moreover, ring sizing can be challenging in some patients and is highly influenced by surgeons' experience. This study investigated the utility of three-dimensional mitral valve (3D-MV) reconstruction models to predict annuloplasty ring size for MVr. METHODS: A total of 150 patients undergoing minimally invasive MVr with annuloplasty ring due to Carpentier type II pathology and who were discharged with none/trace residual mitral regurgitation were included. 3D-MV reconstruction models were created with a semi-automated software package (4D MV Analysis) to quantitate mitral valve geometry. To predict the ring size, univariable and multivariable linear regression analyses were performed. RESULTS: Between 3D-MV reconstruction values and implanted ring sizes, the highest correlation coefficients were provided by commissural width (CW) (0.839; P < 0.001), intertrigonal distance (ITD) (0.796; P < 0.001), annulus area (0.782; P < 0.001), anterior mitral leaflet area (0.767; P < 0.001), anterior-posterior diameter (0.679; P < 0.001) and anterior mitral leaflet length (0.515; P < 0.001). In multivariable regression analysis, only CW and ITD were found to be independent predictors of annuloplasty ring size (R2 = 0.743; P < 0.001). The highest level of agreement was achieved with CW and ITD, and 76.6% of patients received a ring with no >1 ring size difference from the predicted ring sizes. CONCLUSIONS: 3D-MV reconstruction models can support surgeons in the decision-making process for annuloplasty ring sizing. The present study may be a first step towards accurate annuloplasty ring size prediction using multimodal machine learning decision support.

How To Do It: Mitral Valve Translocation.

Mitral valve translocation (MVT) is a novel procedure that was developed to treat patients with severe, symptomatic, secondary mitral regurgitation (MR). MVT enhances leaflet coaptation by insertion of an autologous pericardial patch interposed between the mitral annulus and the native mitral leaflets. The patch substantially increases total leaflet surface area and creates supranormal coaptation. In addition, it relieves leaflet tethering by transposing the native valve deeper into the ventricle and decreases the circumference of the annulus. The enhanced coaptation produced by MVT may protect against recurrent MR in patients with continued adverse left ventricular remodeling. The procedural steps include detachment of the intact native mitral valve at the annulus, placement of interrupted pledgeted sutures around the annulus to secure the proximal aspect of the patch, and attachment of the native valve to the distal aspect of the patch using running suture. Follow-up of patients who have undergoing MVT is ongoing, with satisfactory short-term results, including sustained MR grades of ≤mild and 14 mm coaptation at 12 months.

Predictors of mitral valve haemodynamics after mitral valve repair for degenerative mitral regurgitation.

OBJECTIVE: Intraoperative predictors of functional mitral valve (MV) stenosis after surgical repair of mitral regurgitation (MR) caused by prolapse remain poorly characterised. This study evaluated the effect of annuloplasty size on postoperative MV haemodynamics during exercise and evaluated predictors of MV hemodynamics. METHODS: 104 patients were randomly assigned to leaflet resection or preservation for surgical repair of MR in the Canadian Mitral Research Alliance CardioLink-2 study. In this post hoc analysis, we compared MV haemodynamics between the two surgical groups and examined the relationship between annuloplasty size and MV haemodynamics 1 year after repair in the combined groups. Echocardiograms were performed at baseline and intraoperatively. Exercise transthoracic echocardiography was performed 1 year postoperatively. Multivariable linear regression analysis was used to identify predictors of exercise MV gradients at follow-up. RESULTS: Mean age of participants was 65±10 years, and 83% were male. Median annuloplasty size was 34 (IQR 32-36). Dividing by the median, 48 (46%) had annuloplasty size of <34 mm and 56 (54%) had ≥34 mm. Mean and peak exercise gradients at 1 year were 11±5 mm Hg and 22±9 mm Hg in <34, and 6±3 mm Hg and 14±5 mm Hg in ≥34 (p<0.001). Rate of residual MR was similar in both groups. In multivariable analyses, annuloplasty size of ≥34 mm was associated with lower mean and peak exercise gradients at 12 months, after adjustment for repair type, age, sex, heart rate and body surface area (ß -4.1, 95% CI -6 to -3, p<0.001, and ß -7 95% CI -10 to -4, p<0.001, respectively). Intraoperative mean and peak MV gradients by transesophageal echocardiography independently predicted mean and peak resting and exercise gradients at follow-up (p<0.001). Similar results were obtained in both leaflet resection and preservation. CONCLUSION: Annuloplasty size of ≥34 mm is associated with a 4 and 7 mm Hg reduction in mean and peak exercise MV gradients, respectively, 1 year post MV repair regardless of the repair strategy used. Intraoperative TEE MV gradients predict exercise MV gradients 1 year post repair. TRIAL REGISTRATION NUMBER: NCT02552771.

A mitral valve repair update: simple, intuitive and physiological techniques, using running sutures (part I).

Today's mitral valve techniques are pluralistic, and the result of variable contributions over decades. However, they are often associated with subjectivity, and inter-surgeon variability, as well as differing outcomes. Here, we propose a set of conceptual techniques, which aim to simplify and standardize mitral valve repair, of which some we have already verified in practice.

Beyond the 10-Year Horizon: Mitral Valve Repair Solely With Chordal Replacement and Annuloplasty.

BACKGROUND: The long-term outcomes of mitral valve repair by nonresection techniques, such as annuloplasty and chordal replacement, for degenerative mitral valve regurgitation were investigated. METHODS: All consecutive patients with degenerative mitral regurgitation who received solely chordal replacement and annuloplasty for mitral valve repair between 2003 and 2010 at the German Heart Center Munich were reviewed. The endpoints of this retrospective study were survival, cumulative incidence of reoperation on the mitral valve, and cumulative incidence of significant recurrent mitral regurgitation. RESULTS: A total of 346 patients were evaluated. The median follow-up period was 10.86 (range, 0.01-15.86) years. The 30-day mortality rate was 0.58% (n = 2 of 346), whereas the 5-year survival was 92.97% ± 1.41%. At 5 years, cumulative incidence of recurrent mitral regurgitation was 6.87% ± 1.57% and cumulative incidence of reoperation on the mitral valve was 3.69% ± 1.05%. Survival at 10 years was 83.35% ± 2.15%. At 10 years, cumulative incidence of recurrent mitral regurgitation was 13.31% ± 2.22% and cumulative incidence of reoperation was 7.84% ± 1.55%. Cox regression analysis identified age, diabetes mellitus, and reduced left ventricular ejection fraction <55% as independent risk factors for death. Left ventricular ejection fraction <55% was revealed as independent risk factor for significant recurrent mitral regurgitation. CONCLUSIONS: This study demonstrated excellent long-term outcomes with low incidence of reoperation after mitral valve repair using chordal replacement in a highly selected patient cohort. Our findings emphasized the importance of early intervention in severe degenerative mitral regurgitation, especially in patients with reduced left ventricular ejection fraction.

Left ventricle-mitral valve ring size mismatch following ring annuloplasty for nonischemic dilated cardiomyopathy.

BACKGROUND: In patients with ischemic mitral regurgitation (MR) undergoing restrictive mitral annuloplasty (RMA), the ratio of left ventricular (LV) end-systolic dimension (LVESD) to mitral valve (MV) ring size (ie, LV-MV ring mismatch) is associated with postoperative recurrent MR. However, the impact of LV-MV ring mismatch on postoperative recurrent MR, LV function recovery, and long-term survival in patients with nonischemic dilated cardiomyopathy (DCM) remains unknown. METHODS: Sixty-six patients with nonischemic DCM (mean LVESD, 62 mm) underwent RMA (mean ring size, 26 mm) between 2003 and 2014. Recurrent MR was defined as MR grade ≥2+ at a 6-month echocardiographic evaluation. RESULTS: At the 6-month follow-up, 23 patients (35%) had developed recurrent MR. In univariable logistic regression analysis, larger LVESD (P = .012) and LVESD/ring size ratio (P = .008) were associated with recurrent MR. In multivariable models adjusted for age, sex, baseline LV ejection fraction, and severe MR, only LVESD/ring size ratio (odds ratio, 4.65; 95% confidence interval, 1.04-25.0; P = .048) remained significantly associated with MR recurrence. Receiver operating characteristic curve analysis demonstrated an optimal cutoff value for the LVESD/ring size ratio of 2.42. Patients with an LVESD/ring size ratio >2.42 (n = 30; mismatch) had a lower 5-year cumulative survival rate compared with those with an LVESD/ring size ratio ≤2.42 (n = 36; nonmismatch) (52% vs 71%; P = .045). Postoperatively, LV dimensions were significantly reduced in both groups; however, improvements in LVEF were only modest in the mismatched group (P = .091). CONCLUSIONS: LV-MV ring size mismatch was associated with an increased risk of recurrent MR in our series. This finding may aid the formulation of surgical strategies for patients with nonischemic DCM.

Comparative study of coronary artery bypass grafting combined with off-pump mitral valvuloplasty versus coronary artery bypass grafting alone in patients with moderate ischemic mitral regurgitation.

INTRODUCTION: Whether mitral surgery should be performed simultaneously with coronary artery bypass grafting (CABG) in patients with moderate ischemic mitral regurgitation (MIMR) is controversial. This study was performed to introduce a method of off-pump mitral valvuloplasty after off-pump CABG (OPCABG) and compare it with OPCABG alone. METHODS: Eighty-three patients with MIMR underwent OPCABG. Among them, 21 patients (Group A) underwent posterior mitral annuloplasty without cardiopulmonary bypass, and 62 patients (Group B) underwent OPCABG alone. The primary endpoint of follow-up was the mitral regurgitation area. RESULTS: The mean mitral regurgitant area in Group A and B was 6.42 ± 1.02 and 5.49 ± 1.24 cm2 preoperatively (p = .479), 2.93 ± 1.35 and 3.28 ± 1.93 cm2 at 1 week postoperatively (p = .516), 3.06 ± 2.16 and 3.09 ± 1.85 cm2 at 3 months postoperatively (p = .839), and 3.02 ± 1.60 and 3.7 cm2 (median) at 1 year postoperatively (p = .043). There was less regurgitation in Group A at the mid-term. Intragroup comparison showed significant differences between the preoperative and postoperative values in both groups, with no difference in the regurgitant area at each postoperative time point in Group A but a significant difference between 3 months and 1 year postoperatively in Group B (p = .042). Multiple linear regression showed that the mid-term mitral regurgitant area changes were negatively correlated with graft flow and positively correlated with age. CONCLUSION: In patients with MIMR who underwent OPCABG plus off-pump mitral valve annuloplasty, the mitral regurgitant area was smaller and mitral regurgitation recurrence was less frequent at the mid-term follow-up.

Mitral Repair With Complete Rings or Posterior Bands in Barlow Disease: Long-term Results.

BACKGROUND: Complete rings or posterior bands are both commonly used during mitral valve repair, but which one ensures the best long-term outcome in patients with Barlow disease is a topic of debate. This study evaluated whether the type of annuloplasty device affects the long-term durability of the repair. METHODS: We selected 296 consecutive patients with severe mitral regurgitation due to Barlow disease who underwent edge-to-edge mitral repair at our institution between 2004 and 2013. For the edge-to-edge repair, a complete semirigid ring was used in 151 patients, whereas a posterior flexible band was used in 145 patients. The clinical and echocardiographic outcomes of both groups were compared at long-term follow-up. RESULTS: At 14 years, the overall survival was 87.3% ± 2.79% in the ring group and 94.1% ± 2.30% in the band group (P = .056). The incidence of mitral valve reintervention was 4.9% ± 1.95% in the ring group and 5.5% ± 2.53% in the band group (P = .371) at 14 years. The incidence of recurrence of mitral regurgitation ≥3+ and ≥2+ was 8.3% ± 2.64% in the ring group and 8.7% ± 3.07% in the band group (P = .991) and 26.5% ± 4.23% in the ring group and 17.4% ± 3.26% in the band group (P = .697), respectively. Mitral regurgitation ≥1+ at discharge was the only independent predictor of reoperation and recurrence of mitral regurgitation ≥3+ in the long-term. CONCLUSIONS: In patients with Barlow disease undergoing edge-to-edge mitral valve repair, the type of annuloplasty device does not influence the long-term results. Achieving an optimal immediate result remains the key to maintain the stability of the repair at long-term.

Subannular repair for functional mitral regurgitation with reduced systolic ventricle function: rationale and design of REFORM-MR registry.

BACKGROUND: Functional mitral regurgitation (FMR) is one of the most common heart valve diseases that is a sequel of left ventricular remodelling. Although mitral valve annuloplasty is a standard treatment of FMR, the recurrence of FMR is a major drawback and occurs in 10-50% of patients. The REFORM-MR registry aims to investigate the effectiveness of standardized papillary muscle relocation and ring annuloplasty and to identify the risk factors associated with recurrent FMR. METHODS: REFORM-MR is a prospective, multicenter registry that enrols consecutive FMR patients across five sites in Germany. All patients with FMR and restricted movement of leaflets during systole (i.e., type IIIb mitral regurgitation) undergoing standardized subannular repair in combination with mitral valve annuloplasty are included in the study. The primary objective is to examine the effect of combined papillary muscle relocation and ring annuloplasty on the recurrence of FMR at 2 years postoperatively. The secondary objectives are MACCE rate, reinterventions on the mitral valve and cardiac-related mortality in the study cohort. Echocardiography core-lab and MRI core-lab will provide anonymized analysis of the imaging data in the REFORM-MR registry. Student's t-test or Mann-Whitney U test for continuous variables and the Chi-Square or Fisher exact test for categorical variables are used for group comparisons. Kaplan-Meier analyses is performed for survival and safety outcomes. RESULTS: As of May 2021, a total of 97 patients were enrolled across five sites in Germany. CONCLUSIONS: The results of this study will help define the outcomes of combined papillary muscle relocation and ring annuloplasty in the FMR treatment in a multicentre setting and to improve the understanding of the limitations of subannular repair procedures while treating patients with type III FMR. Trial registration clinicaltrials.gov Identifier: NCT03470155.