Barlow's Disease Research Articles

Feasibility validation of automatic diagnosis of mitral valve prolapse from multi-view echocardiographic sequences based on deep neural network.

To address the limitations of traditional diagnostic methods for mitral valve prolapse (MVP), specifically fibroelastic deficiency (FED) and Barlow's disease (BD), by introducing an automated diagnostic approach utilizing multi-view echocardiographic sequences and deep learning. An echocardiographic data set, collected from Zhongshan Hospital, Fudan University, containing apical 2 chambers (A2C), apical 3 chambers (A3C), and apical 4 chambers (A4C) views, was employed to train the deep learning models. We separately trained view-specific and view-agnostic deep neural network models, which were denoted as MVP-VS and MVP view-agonistic (VA), for MVP diagnosis. Diagnostic accuracy, precision, sensitivity, F1-score, and specificity were evaluated for both BD and FED phenotypes. MVP-VS demonstrated an overall diagnostic accuracy of 0.94 for MVP. In the context of BD diagnosis, precision, sensitivity, F1-score, and specificity were 0.83, 1.00, 0.90, and 0.92, respectively. For FED diagnosis, the metrics were 1.00, 0.83, 0.91, and 1.00. MVP-VA exhibited an overall accuracy of 0.95, with BD-specific metrics of 0.85, 1.00, 0.92, and 0.94 and FED-specific metrics of 1.00, 0.83, 0.91, and 1.00. In particular, the MVP-VA model using mixed views for training demonstrated efficient diagnostic performance, eliminating the need for repeated development of MVP-VS models and improving the efficiency of the clinical pipeline by using arbitrary views in the deep learning model. This study pioneers the integration of artificial intelligence into MVP diagnosis and demonstrates the effectiveness of deep neural networks in overcoming the challenges of traditional diagnostic methods. The efficiency and accuracy of the proposed automated approach suggest its potential for clinical applications in the diagnosis of valvular heart disease.

Recurrent mitral regurgitation after repair of Barlow's disease in a single-center retrospective cohort study.

Barlow's disease (BD) is a common etiology of degenerative mitral valve (MV) disease, often causing significant mitral regurgitation (MR). The pathology of BD is challenging for surgeons performing MV repair (MVR). However, most MVR effectiveness studies have been based on survival and risk of reoperation. The aim of this study was to analyze the safety, efficacy, and durability of MVR in patients with BD and to identify factors that influence recurrent MR. We retrospectively analyzed the clinical outcomes of 274 patients undergoing MVR for BD at a tertiary hospital (Guangdong People's Hospital, Guangzhou, China) between January 2010 and June 2022. To analyze the results of MVR and identify the risk factors for MR recurrence, we defined two groups: a total of 240 patients with MR grade <2+ (group A) and a total of 34 patients who had recurrent MR after MVR (group B; the patients with MR ≥2+). All patients were operated on using standard repair techniques. Recurrent MR was the primary outcome. Secondary outcomes were death and reoperation after MVR. Patients were followed up until March 2023. Patients were followed up by clinic visits, telephone calls, and postal or electronic questionnaires. The median [range] patient age was 46.00 [16-75] years and 186 (67.9%) patients were male. Concomitant procedures were performed in 123 patients: tricuspid valve repair 71 (25.9%), maze or pulmonary vein isolation (PVI) 12 (4.4%), atrial septal defect (ASD) repair 3 (1.1%), and left atrial appendage (LAA) closure 28 (10.2%). Hospital mortality was 0.4%. Long-term complications included radiofrequency ablation in 7 patients (2.6%), pacemaker implantation in 1 patient (0.4%), and stroke in 3 patients (1.1%). The median follow-up was 3.28 (range, 0-12.39) years. Considering the competing risk of mortality, the cumulative incidence of MR progression 2+ or more grades was 2.6%, 5.9%, 14.5%, and 27.7% at 1 month, 1, 5, and 10 years, respectively. Overall survival at 1, 5, and 10 years was 99.3%, 98.6%, and 98.6%, respectively. The immediate postoperative MR area [hazard ratio (HR) =1.723; 95% confidence interval (CI): 1.051-2.824; P=0.031], postoperative left ventricular end-diastolic dimension (LVEDD) (HR =1.149; 95% CI: 1.016-1.300; P=0.027), and postoperative MR grade {HR = Exp[4.500 - 0.544 × ln(t + 20)]; P=0.008} were associated with an increased risk of MR recurrence, whereas a higher left ventricular ejection fraction (LVEF) (HR =0.931; 95% CI: 0.868-0.999; P=0.049) was associated with a decreased risk. MVR in patients with BD can be performed with low mortality and complications and is associated with superior long-term outcomes. However, MVR was associated with a certain risk of MR recurrence, especially in those with high postoperative LVEDD, residual MR >1+, and decreased postoperative LVEF. We recommend MVR for patients with BD, especially for those with early-stage disease. However, future randomized controlled trials are needed to confirm this.

Impact of Complex Anatomy and Patient Risk Profile in Minimally Invasive Mitral Valve Surgery

BackgroundWe aimed to assess the impact of complex mitral valve disease and patient risk profile on operative outcomes in the large cohort of the Mini-Mitral International Registry. MethodsPatients were assigned to categories of complex degenerative mitral valve regurgitation (DMR; bileaflet or anterior mitral leaflet prolapse/flail) and simple DMR (posterior mitral leaflet prolapse/flail). Subgroup analyses was performed in low-risk (EuroSCORE II <8%) and high-risk (EuroSCORE II >8%) cohorts. A logistic regression model was applied to investigate the impact of valve anatomy and patient risk factors on valve repair rate and operative risk. ResultsThe study cohort consisted of 4524 patients with DMR (complex DMR, 1296; simple DMR, 3228). Valve repair rate was 87.3% and 91% in complex DMR and simple DMR, respectively. Predictors of valve replacement were anterior leaflet prolapse/flail, bileaflet flail, female sex, age, and reoperation, whereas Barlow disease was protective. Clinical results were comparable between complex DMR and simple DMR. On subgroup analyses, high-risk patients showed less satisfactory outcomes with respect to both the valve repair and operative mortality rates. ConclusionsOur findings suggest that complex DMR can be satisfactorily addressed by minimally invasive techniques. However, whereas complex disease was associated with low operative risk, anterior leaflet lesions and bileaflet flail remain negative predictors of successful valve repair. Conversely, valve repair rate was less satisfactory in high-risk patients, regardless of DMR complexity.

Mitral valve repair with resection and non-resection techniques in Barlow's disease: A multi-center study

BackgroundVarious mitral valve (MV) repair techniques are nowadays in use. Non-resection techniques, that rely exclusively on Gore-Tex® neochords and annuloplasty, have been popularized; however, their efficacy in Barlow's disease, characterized by large myxomatous leaflets, is yet unclear. MethodsConsecutive patients undergoing MV repair for Barlow's disease between 2011 and 2019 were selected on the basis of being eligible for resection and non-resection techniques. Study endpoints included overall survival, freedom from MV reintervention and recurrent regurgitation. ResultsOf 209 patients meeting the inclusion criteria, 135 (65%) underwent MV repair with and 74 (35%) without resection. There was one early reoperation due to residual regurgitation (resection group). Mean clinical follow-up duration was 6.1 (IQR 3.9–8.5) years. At 6 years after surgery, there was no difference in overall survival or freedom from MV reintervention. Mean echocardiographic follow-up (95% complete) duration was 3.5 (IQR 2.3–5.8) years. At 6 years, there was no difference in freedom from recurrent regurgitation rate (86.1%, 95% CI 78.5–93.7% vs. 83.0%, 95% CI 71.6–94.4%, P = 0.20) between the groups. Inverse probability-of-treatment weighting adjusted analysis demonstrated no significant difference between groups (HR 0.535, 95% CI 0.212–1.349, P = 0.20). Uni- and multivariable Cox proportional regression analysis did not demonstrate an effect of valve repair technique on the occurrence of recurrent regurgitation. ConclusionsAt mid-term, the clinical and echocardiographic results of valve repair for Barlow's disease were very good and MV reintervention was rarely needed. At this time point, the results of non-resection techniques were comparable to the “gold standard” resection techniques.

A balanced mitral leaflet and large ring strategy avoids systolic anterior motion in Barlow's disease.

Mitral valve repair for Barlow's disease offers good outcomes but excessive and myxomatous valvular tissue is associated with systolic anterior motion. Although valvular disease might progress after repair and cause long-term systolic anterior motion, few reports focus on this aspect. Herein, we will review our 16-year experience with mitral valve repair for Barlow's disease and systolic anterior motion incidence. We retrospectively reviewed surgical outcomes of 92 cases of mitral valve repair using a balanced leaflet/large ring strategy plus median sternotomy for Barlow's disease (median age 45.1 ± 12.7years old [19-72], 37 females) from 2004 to 2019. Concomitant surgeries, except for tricuspid valve or anti-arrhythmic surgeries, were excluded. The follow-up period was 5.8 ± 4.4years with no deaths. Patients had mitral regurgitation of grade 3/4 (15 cases) or 4/4 (77 cases) due to anterior leaflet (3 cases), posterior leaflet (75 cases), or bileaflet (14 cases) prolapse, with chord elongation (39 cases), chord rupture (22 cases), or a combination of both (14 cases). All cases required ring annuloplasty (median size of 33.0 ± 5.4mm) combined with leaflet resection (91 cases), chord intervention (12 cases), or indentation closure (2 cases). No case had short- or long-term SAM. The freedom-from-mitral-regurgitation (of greater than grade 2/4) rate was 94.1% over 5years and 76.0% over 10years without reoperation. Our two-pronged strategy for mitral valve repair in Barlow's disease avoids systolic anterior motion over the long-term, with good outcomes.

Five-year outcomes of different techniques for minimally invasive mitral valve repair in Barlow's disease.

Barlow's disease is a specific sub-form of mitral valve (MV) disease, characterized by diffuse excessive tissue and multi segment prolapse. The anterolateral mini-thoracotomy represents the standard access for MV regurgitation in many centres. It still remains unclear which surgical technique provides the best results. Therefore, the aim of this study was to compare operative safety and mid-term outcomes after (i) isolated annuloplasty, (ii) use of additional artificial chordae or (iii) leaflet resection in patients suffering from Barlow's disease undergoing minimally invasive MV repair. A consecutive series of patients suffering from Barlow's disease undergoing minimally invasive MV surgery between 2001 and 2020 were analysed (n = 246). Patients were grouped and analysed according to the used surgical technique. The primary outcome was a modified Mitral Valve Academic Research Consortium combined end-point of mortality, reoperation due to repair failure or reoccurrence of severe mitral regurgitation within 5 years. The secondary outcome included operative success and safety up to 30 days. No significant difference was found between the 3 surgical techniques with regard to operative safety (P = 0.774). The primary outcome did not differ between groups (P = 0.244). Operative success was achieved in 93.5% and was lowest in the isolated annuloplasty group (77.1%). Conversion to MV replacement was increased in patients undergoing isolated annuloplasty (P < 0.001). Isolated annuloplasty, use of additional artificial chordae and leaflet resection represent feasible techniques in Barlow patients undergoing minimally invasive MV surgery with comparable 5-year results. In view of the increased conversion rate in the annuloplasty group, the pathology should not be oversimplified.

Structural and functional abnormalities of left-sided cardiac chambers in Barlow's disease without significant mitral regurgitation.

This study aims to explore the presence of left ventricular (LV) and left atrial (LA) morphological and functional abnormalities in patients with Barlow's disease (BD) without significant mitral regurgitation (MR) and to investigate whether these abnormalities may predict MR progression. Consecutive patients with BD were retrospectively identified from two tertiary centres; those with MR graded from trivial to mild-to-moderate were selected and matched with healthy controls in a 1:1 ratio. Conventional and speckle-tracking echocardiographic data were collected. The development of moderate-to-severe or greater MR was evaluated on follow-up echocardiograms. Patients with BD (n = 231) showed increased LV dimensions and indexed LV mass (LVMi) in comparison with controls (P < 0.001); LV remodelling worsened with higher MR severity and was accompanied by an increased prevalence of eccentric LV hypertrophy (eLVH). Moreover, BD patients had larger LA volumes and more impaired LA reservoir strain vs. controls (P < 0.001), while LV strain was similar between the two groups. Multivariable linear regression analyses in the overall population identified BD and MR grade as independent predictors of remodelling markers (LV dimensions, LVMi, and LA volume) and BD as independent correlate of LA strain. MR progression was observed in 51 BD subjects (out of 170 patients with available follow-up). On Cox regression analysis, age, eLVH, mild-to-moderate MR, and mitral annular disjunction (MAD) emerged as independent predictors of MR progression. BD patients without significant MR show early LV and LA remodelling, together with reduced LA strain. MR progression was associated with eccentric LV remodelling, MAD, and MR severity.

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

This study aimed to confirm the safety and feasibility of totally endoscopic repair for mitral regurgitation (MR) in Barlow's disease. 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. 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. 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.

Non-resectional cordal repair for Barlow mitral valve disease.

The redundant leaflet tissue and annular pathology of Barlow disease can make surgical repair challenging. We examined perioperative and late outcomes of a large cohort of patients with Barlow disease undergoing surgical repair. Patients included in this analysis underwent mitral valve repair from 01/2004-11/2021 by a single surgeon. Of 2798 patients undergoing mitral valve operations, 46% (N.=1292) had degenerative pathology and 7% (N.=184) had Barlow disease. Of the 179 Barlow patients, median age at surgery was 62 (51-70) years; 64% were male (115/179). Rates of non-resectional cordal repair and resectional repair were 86% (154/179) and 14% (25/179). Among patients undergoing non-resectional repair, the median number of cordal pairs inserted on the anterior and posterior leaflets was 2 (2-3) and 4 (3-4). Incidence of return to bypass for systolic anterior motion of the mitral valve, perioperative death, stroke, and renal failure was 2% (4/179), 1% (2/179), 0% (0/179), and 0% (0/179). Rates of clinical and echocardiographic follow-up were 93% (165/177) and 89% (157/177). Median time to latest postoperative clinical and echocardiographic follow-up was 2.4 (0.8-6.1) and 2.1 (0.6-4.7) years. Mitral regurgitation grade at latest follow-up or time of repair failure was none/trace, mild, mild to moderate, and severe in 63% (98/157), 26% (41/157), 8% (12/157), and 4% (6/157); five of six patients with severe MR underwent reoperation. Since 2011 97% (139/144) of patients underwent cordal repair without resection. Non-resectional artificial cordal repair is safe and feasible in almost all patients with Barlow valves and is associated with excellent mid-term results.

Mitral Valve Surgery for Mitral Regurgitation Results in Reduced Left Ventricular Ejection Fraction in Barlow's Disease as Compared with Fibro-Elastic Deficiency.

Surgical correction of severe mitral regurgitation (MR) can reverse left ventricular (LV) remodeling in patients with mitral valve prolapse (MVP). However, whether this process is similar to the case in Barlow's Disease (BD) and Fibro-elastic Deficiency (FED) is currently unknown. The aim of this study is to evaluate post-operative LV reverse remodeling and function in patients with BD versus FED. In this study, 100 MVP patients (BD = 37 and FED = 63) with severe MR who underwent mitral valve surgery at three Belgian centers were retrospectively included. Transthoracic echocardiography was used to assess MR severity, LV volumes and function before surgery and 6 months thereafter. Baseline MR severity, LV ejection fraction (LVEF), indexed LV end-diastolic (LVEDVi) and end-systolic volumes (LVESVi) were not different between the groups. After a median follow-up of 278 days, there was a similar decrease in LVEDVi, but a trend towards a smaller decrease in LVESVi in BD compared to FED (-3.0 ± 11.2 mL/m2 vs. -5.3 ± 9.0 mL/m2; p = 0.154). This resulted in a significantly larger decrease in LVEF in BD (-8.3 ± 9.6%) versus FED (-3.9 ± 6.9%) after adjusting for baseline LVEF (p < 0.001) and type of surgical intervention (p = 0.01). These findings suggest that LV (reverse) remodeling in BD could be affected by other mechanisms beyond volume overload, potentially involving concomitant cardiomyopathy.

Mitral valve early systolic billowing induces following annular expansion and leaflet augmentation in Barlow's disease: sequential analysis using 3D echocardiography.

Although systolic expansion of the annulus has been recognized in Barlow's disease, the mechanisms of the unique pathological movement of the annulus and its relation to the leaflet augmentation have not yet been clarified. We aimed to investigate the detailed mechanisms of the characteristic mitral apparatus dynamics in Barlow's disease by frame-by-frame sequential geometric analysis using real-time 3D transoesophageal echocardiography. Fifty-three patients with Barlow's disease and severe mitral regurgitation without torn chordae, as well as 10 controls, were included. We evaluated geometric changes in the mitral complex using 3D transoesophageal echocardiography at five points during systole. To identify early systolic billowing of leaflets, the annulo-leaflet angle was measured. We also performed a more detailed analysis in four consecutive frames just before and after leaflet free-edge prolapse above the annulus plane. The median annulo-leaflet angle of both leaflets in early systole was >0° (above annulus plane) in patients with Barlow's disease, and billowing of the leaflet body was observed from early systole. The prolapse volume of both leaflets increased markedly from early to mid-systole [1.60 (0.85-2.80) to 4.00 (2.10-6.45) mL; analysis of variance (ANOVA), P < 0.001; post hoc, P < 0.05]. With frame-by-frame analysis, dynamic augmentation of the annulus and leaflets developed between frames just before and just after leaflet free-edge prolapse (ANOVA, P < 0.01; post hoc, P < 0.05). In Barlow's disease, early systolic billowing of the mitral leaflet induces systolic annulus expansion followed by leaflet augmentation and leaflet free-edge prolapse.

A Comparative Study of 1-Year Postprocedural Outcomes in Transcatheter Mitral Valve Repair in Advanced Primary Mitral Regurgitation: PASCAL vs. MitraClip.

Both the MitraClip and PASCAL systems offer transcatheter edge-to-edge repair (TEER) solutions for mitral regurgitation. Evidence indicates a lower technical success rate for TEER in complex degenerative mitral regurgitation (DMR) cases. We conducted a retrospective analysis of patients who underwent transcatheter edge-to-edge therapy for primary mitral regurgitation with advanced anatomy, defined as mitral regurgitation effective regurgitant orifice area (MR-EROA) ≥0.40 cm2 or large flail gap (≥5 mm) or width (≥7 mm) or Barlow's disease, that completed follow-up after 1 year. Our criteria were met by 27 patients treated with PASCAL and 18 with MitraClip. All patients exhibited a significant, equivalent short-term reduction in MR-EROA, mitral regurgitation vena contracta diameter (MR-VCD), regurgitant volume, and clinical status. At 1 year follow-up, reductions in MR-VCD, regurgitant volume, and MR-EROA remained significant for both groups without significant differences between groups. MR-Grade ≤ 1+ was achieved in 18 (66.7%) and 10 (55.6%) patients, respectively. At follow-up, no difference in hospitalization for cardiac decompensation was observed. Overall death was similar in both groups. Our study suggests that both the PASCAL and MitraClip systems significantly reduce mitral regurgitation even in advanced degenerative diseases. Within our limited data, we found no evidence of inferior performance of the PASCAL system.

Structural and functional abnormalities of cardiac chambers in Barlow disease without significant mitral regurgitation

Abstract Background Limited and conflicting data have been reported on the existence of an early chamber remodelling in patients with Barlow disease (BD) without significant mitral regurgitation (MR). Purpose To explore the presence of left ventricular (LV) and left atrial (LA) morphological and functional abnormalities, evaluated by conventional and speckle-tracking echocardiography, in patients with BD and without significant MR; in addition, potential determinants of MR progression in these patients have been investigated. Methods We retrospectively identified consecutive patients with BD evaluated in two tertiary centers between 2010 and 2021. Only patients with MR graded from trivial to mild-to-moderate, as defined by an integrated multiparametric echocardiographic assessment, were selected. BD patients were matched with healthy controls with similar demographic characteristics and prevalence of cardiovascular risk factors, in a 1:1 ratio. A comprehensive echocardiographic evaluation, including LV and LA strain assessment by speckle-tracking analysis, was performed in all patients. Follow-up echocardiograms, when available, were reviewed in BD patients to evaluate the MR progression. Results A total of 231 patients with BD were included, of which 109 (56%) had trivial or mild MR and the remaining 122 (44%) had mild-to-moderate MR. As showed in Figure 1, patients with BD showed increased LV dimensions and indexed LV mass (LVMi), as compared with controls (all p&amp;lt;0.001); LV remodelling worsened with higher degree of MR (trivial-mild vs mild-to-moderate) and was accompanied by an increased prevalence of eccentric LV hypertrophy (eLVH). Conversely, parameters of LV systolic performance, including LV strain, were similar to controls and between the two groups. In addition, BD patients had larger LA volumes and more impaired LA reservoir strain than controls (p&amp;lt;0.001), without differences in the latter according to MR severity. Multivariable linear regression analyses in the overall population identified BD and MR grade as independent predictors of remodelling markers (LV dimensions, LVMi and LA volumes), and BD as independent correlate of LA reservoir strain. Progression to moderate-to-severe or greater MR was observed in 51 subjects (on 172 with available follow-up) after a median time of 38 (range: 24-68) months. On multivariable Cox regression analysis, LVMi (or alternatively eLVH), together with age, MR grade and the presence of mitral annular disjunction emerged as independent predictors of MR progression (Figure 2). Conclusions Patients with BD and no significant MR show an early LV and LA remodeling, together with a mild impairment of LA reservoir strain, but not of LV function. LV remodelling, and the presence of eLVH in particular, portends a higher risk of MR progression.Comparative echocardiographic analysisMultivariable Cox regression analyses

Mechanical behavior and collagen structure of degenerative mitral valve leaflets and a finite element model of primary mitral regurgitation.

Degenerative mitral valve disease is the main cause of primary mitral regurgitation with two phenotypes: fibroelastic deficiency (FED) often with localized myxomatous degeneration and diffuse myxomatous degeneration or Barlow's disease. Myxomatous degeneration disrupts the microstructure of the mitral valve leaflets, particularly the collagen fibers, which affects the mechanical behavior of the leaflets. The present study uses biaxial mechanical tests and second harmonic generation microscopy to examine the mechanical behavior of Barlow and FED tissue. Three tissue samples were harvested from a FED patient and one sample is from a Barlow patient. Then we use an appropriate constitutive model by excluding the collagen fibers under compression. Finally, we built an FE model based on the echocardiography of patients diagnosed with FED and Barlow and the characterized material model and collagen fiber orientation. The Barlow sample and the FED sample from the most affected segment showed different mechanical behavior and collagen structure compared to the other two FED samples. The FE model showed very good agreement with echocardiography with 2.02±1.8mm and 1.05±0.79mm point-to-mesh distance errors for Barlow and FED patients, respectively. It has also been shown that the exclusion of collagen fibers under compression provides versatility for the material model; it behaves stiff in the belly region, preventing excessive bulging, while it behaves very softly in the commissures to facilitate folding. STATEMENT OF SIGNIFICANCE: This study quantifies for the first time the collagen microstructure and mechanical behavior of degenerative mitral valve (DMV) leaflets. These data will then be used for the first disease-specific finite element (FE) model of DMV. While current surgical repair of DMV is based on surgical experience, FE modeling has the potential to support decision-making and make outcomes predictable. We adopt a constitutive model to exclude collagen fiber under compressions, an important consideration when modeling the mitral valve, where the leaflets are folded to ensure complete closure. The results of this study provide essential data for understanding the relationship between collagen microstructure and degenerative mitral valve mechanics.

The impact of mitral valve surgery on ventricular arrhythmias in patients with Barlow's disease: preliminary results of a prospective study.

Aim of this study was to evaluate arrhythmic burden of patients with Barlow's disease and significant mitral regurgitation (MR) and assess the impact of mitral repair on ventricular arrhythmias (VA) in this group of subjects. We prospectively included 88 consecutive patients with Barlow's disease referred to our Institution from February 2021 to May 2022. All enrolled patients underwent 24-h Holter monitoring before surgery. Sixty-three of them completed 3 months echocardiographic and Holter follow-up. Significant arrhythmic burden was defined as ≥1% premature ventricular beats/24 h or at least one episode of non-sustained ventricular tachycardia (VT), VT or ventricular fibrillation. At baseline, 29 patients (33%) were arrhythmogenic (AR), while 59 (67%) were not [non-arrhythmogenic (NAR)]. AR subjects tended to be more often females with history of palpitations. Sixty-three patients completed 3-months follow-up. Twenty of them (31.7%) were AR at baseline and 43 (68.3%) were not. Among AR patients, 9 (45%) remained AR after mitral surgery, while 11 (55%) became NAR. Considering NAR subjects at baseline, after mitral valve repair 8 (18.6%) evolved into AR, while 35 (81.4%) remained NAR. A higher prevalence of pre-operative MAD was found among patients experiencing VA reduction if compared with patients who remained arrhythmogenic (63.6% vs 11.1%, P = 0.028). In our experience, one-third of Barlow's patients referred for mitral surgery showed a significant arrhythmic burden. Almost half of the subjects arrhythmogenic at baseline were free from significant VA after mitral repair. However, a minority (18.6%) of subjects without arrhythmic burden at baseline experienced significant VA at follow-up.

Barlow's disease with arrhythmic phenotype: a case report

Barlow disease represents the extreme form of the degenerative mitral valve spectrum described by Carpentier. The myxoid degeneration of the mitral valve may result in a billowing leaflet or in a prolapse and myxomatous degeneration of the mitral leaflets. There are increasing evidences of the association between Barlow disease and sudden cardiac death. It is common in young women. Symptoms include anxiety, chest pain and palpitation. In this case report, the markers of risk for sudden death such as typical ECG changes, complex ventricular ectopy, a spiked configuration of the lateral annular velocities, mitral annular disjunction and evidence of myocardial fibrosis were assessed.

The evolving role of cardiovascular magnetic resonance in the assessment of mitral valve prolapse.

Mitral valve prolapse (MVP), characterized by a displacement > 2 mm above the mitral annulus of one or both bileaflets, with or without leaflet thickening, is a common valvular heart disease, with a prevalence of approximately 2% in western countries. Although this population has a generally good overall prognosis, MVP can be associated with mitral regurgitation (MR), left ventricular (LV) remodeling leading to heart failure, ventricular arrhythmia, and, the most devastating complication, sudden cardiac death, especially in myxomatous bileaflet prolapse (Barlow's disease). Among several prognostic factors reported in the literature, LV fibrosis and mitral annular disjunction may act as an arrhythmogenic substrate in this population. Cardiac magnetic resonance (CMR) has emerged as a reliable tool for assessing MVP, MR severity, LV remodeling, and fibrosis. Indeed, CMR is the gold standard imaging modality to assess ventricular volume, function, and wall motion abnormalities; it allows accurate calculation of the regurgitant volume and regurgitant fraction in MR using a combination of LV volumetric measurement and aortic flow quantification, independent of regurgitant jet morphology and valid in cases of multiple valvulopathies. Moreover, CMR is a unique imaging modality that can assess non-invasively focal and diffuse fibrosis using late gadolinium enhancement sequences and, more recently, T1 mapping. This review describes the use of CMR in patients with MVP and its role in identifying patients at high risk of ventricular arrhythmia.

In silico analysis provides insights for patient-specific annuloplasty in Barlow's disease

ObjectiveTo predict the required mitral annular area reduction in patients with Barlow's disease to obtain a predefined leaflet area index by a novel in silico modeling method. MethodsThree-dimensional echocardiography was used to create patient-specific mitral valve models of 8 patients diagnosed with Barlow's disease and bileaflet prolapse preoperatively. Six patients were also studied postoperatively in a finite element framework, to quantify the optimal coaptation area index. For the patient-specific finite element analyses, realistic papillary muscle and annular motion are incorporated, also for the in silico annuloplasty analyses. The annuloplasty ring size is reduced moderately until the optimal coaptation area index is achieved for each patient. ResultsThe mean mitral annular area at end-diastole was reduced by 58 ± 7% postoperatively (P < .001), resulting in a postoperative coaptation area index of 20 ± 5%. To achieve the same coaptation area index with moderate annular reductions and no leaflet resection the annular reduction was 31 ± 6% (P < .001). ConclusionsIn silico analysis in selected patients diagnosed with Barlow's disease demonstrates that annuloplasty with only moderate annular reduction may be sufficient to achieve optimal coaptation as compared to conventional surgical procedures.

Болезнь Барлоу на примере клинического наблюдения

Barlow's disease (BD) is one of the dominant forms of degenerative mitral valve (MV) disease characterized by morphological changes of the connective tissue triggering the mechanism of mitral valve leaflet coaptation failure. The disease is characterized by MV prolapse driven by chordal rupture or elongation, leaflet area enlargement and annular ectasia. Typical BD symptoms are found in 24% of patients with mitral valve prolapse (MPV). It should be noted that BD is a heritable disorder. Patients with BD are typically young women (less than 40-year-old), who remain asymptomatic for a long time. BD is often diagnosed incidentally, during the screening examination. Radical correction of such MV dysfunction can be achieved only by using surgical techniques. Based on echocardiography findings, two types of Barlow's disease are distinguished: a classical one with MV leaflet thickening and a non-classical — without its thickening (presumably associated with dysplasia of the connective tissue). This article is focused on the foundations of semiotics and the main principles of BD patient management. It provides a review of MVP and mitral incompetence causes and describes a clinical case of surgical BD treatment. KEYWORDS: mitral regurgitation, plastic surgery of the mitral valve, Barlow's disease, mitral valve prolapse, heritable disorders of connective tissue, dysplasia. FOR CITATION: Reznik E.V., Golubev Yu.Yu., Yurtaeva N.V. et al. Barlow's disease illustrated by a clinical case. Russian Medical Inquiry. 2023;7(1):41–48 (in Russ.). DOI: 10.32364/2587-6821-2023-7-1-41-48.

962 CASE REPORT: ARRHYTHMIC MITRAL VALVE PROLAPSE - STATE OF THE ART AND WHAT'S NEW

Abstract Background Mitral valve prolapse (MVP) is a well-known pro-arrhythmic condition that involves 2-3% of the general population with an incidence of nonfatal arrhythmic events up to 30% and sudden cardiac death of 2-4% per year. It is assumed that the pro-arrhythmic substrate consists in myocardial fibrosis, secondary to steer-stretch due to the anomalous mobility of the mitral valve apparatus. We still have gaps in the evidences about the arrhythmic risk stratification of MVP and the most appropriate therapy and follow-up. Clinical case We present the case of a 40-years-old man with a known MVP due to Barlow disease, who underwent an at-home resuscitated cardiopulmonary arrest. In hospital, an echocardiogram found left ventricular dilatation with diffuse hypokinesia and severe mitral insufficiency. A coronary angiogram showed an undamaged coronary tree. The 24h ECG monitoring showed very frequent ventricular ectopies and non-sustained ventricular tachycardia. The patient underwent valvular surgery and he is now waiting for cardiac defibrillator (ICD) implantation. Conclusion We discuss the state of the art in risk stratification of “malignant” MVP; the actual and potential future role of the cardiac magnetic resonance, ICD implantation, sympathetic modulation, and early surgical mitral valve repair, in the primary prevention of sudden cardiac death.