Comparison of Mitral Valve Repair Versus Percutaneous Mitral Balloon Commissurotomy for Patients With Rheumatic Heart Disease: A Single-Centre Study.

BACKGROUND: Percutaneous mitral balloon commissurotomy (PMBC) is the standard treatment option for patients with rheumatic mitral stenosis (MS), according to current guidelines. This study aimed to compare the outcomes of rheumatic mitral valve repair (rMVR) and PMBC in this patient population. METHODS: Baseline, clinical, and follow-up data from 703 patients with rheumatic heart disease who underwent PMBC or rMVR at the current centre were collected and analysed. A 1:1 propensity score (PS) matching method was used to balance the differences in baseline characteristics between the two groups. The primary outcome was mitral valve reoperation, and the secondary outcome was all-cause mortality. RESULTS: Propensity score matching generated 101 patient pairs for comparison. In the matched population, there were no significant differences in the early clinical outcomes between the groups. The median follow-up time was 40.9 months. Overall, patients in the rMVR group had a statistically significantly lower risk of mitral valve reoperation than those in the PMBC group (HR 0.186; 95% CI 0.041-0.835; p=0.028). Regarding all-cause mortality, no statistically significant differences were observed between the rMVR and PMBC groups (HR 4.065; 95% CI 0.454-36.374; p=0.210). CONCLUSIONS: Compared with PMBC, rMVR has more advantages for the correction of valve lesions; therefore, it may offer a better prognosis than PMBC in select patients with rheumatic MS. However, this finding needs to be verified in future studies with larger sample sizes and longer follow-up periods.

The Association Between Late Gadolinium Enhancement by Cardiac Magnetic Resonance and Ventricular Arrhythmia in Patients With Mitral Valve Prolapse: A Systematic Review and Meta-Analysis.

INTRODUCTION: Malignant ventricular arrhythmia (VA) and sudden cardiac death (SCD) have been reported in patients with mitral valve prolapse (MVP); however, effective risk stratification methods are still lacking. Myocardial fibrosis is thought to play an important role in the development of VA; however, observational studies have produced contradictory findings regarding the relationship between VA and late gadolinium enhancement (LGE) in MVP patients. The aim of this meta-analysis and systematic review of observational studies was to investigate the association between left ventricular LGE and VA in patients with MVP. METHODS: We searched the PubMed, Embase, and Web of Science databases from 1993 to 2023 to identify case-control, cross-sectional, and cohort studies that compared the incidence of VA in patients with MVP who had left ventricular LGE and those without left ventricular LGE. RESULTS: A total of 1464 subjects with MVP from 12 observational studies met the eligibility criteria. Among them, VA episodes were reported in 221 individuals (15.1%). Meta-analysis demonstrated that the presence of left ventricular LGE was significantly associated with an increased risk of VA (pooled risk ratio 2.96, 95% CI: 2.26-3.88, p for heterogeneity = 0.07, I2 = 40%). However, a meta-regression analysis of the prevalence of mitral regurgitation (MR) showed that the severity of MR did not significantly affect the association between the occurrence of LGE and VA (p = 0.079). CONCLUSION: The detection of LGE could be helpful for stratifying the risk of VA in patients with MVP.

Mitral Valve Repair with Leaflet Resection versus Preservation for Degenerative Posterior Leaflet Prolapse.

OBJECTIVES: The optimal technique for repairing posterior mitral valve (MV) leaflet (PMVL) prolapse remains undetermined. We aimed to compare leaflet resection and neo-chordae implantation in patients undergoing MV repair for posterior leaflet prolapse, focusing on trans-mitral pressure gradient (PG) and recurrence of mitral regurgitation (MR). METHODS: We enrolled patients undergoing MV repair using either leaflet resection or neo-chordae implantation for single-segment prolapse of PMVL between 2000 and 2021 at our institution. Longitudinal outcomes were evaluated after adjustments with inverse-probability-of-treatment weighting (IPTW). Repeat echocardiographic measurements (n=3,473, 5.4/patient) of trans-mitral PG and significant (moderate or severe) MR recurrence were estimated using nonlinear mixed-effect models. Subgroup analyses were conducted based on the size and type of prosthesis. RESULTS: Among 639 patients, leaflet resection was used in 479 (75.0%) and neo-chordae implantation in 160 (25.0%). In the IPTW-adjusted cohort, the risk of death (P=0.623) and MV reoperation (P=0.340) did not significantly differ between the two groups during a median follow-up of 97.3 months. Echocardiographic data showed comparable mean (at 5 years, 3.8 vs. 4.0 mmHg; P=0.442) and peak (9.6 vs. 10.4mmHg; P=0.131) PGs between groups, which persisted in most subgroup analyses. However, neo-chordae implantation was associated with a higher probability of significant MR recurrence compared to leaflet resection (at 5 years, 16.1% vs. 7.0%; P<0.001). CONCLUSIONS: Leaflet resection yielded similar clinical outcomes and trans-mitral PGs compared to neo-chordae implantation after MV repair, with a lower MR recurrence rate. These findings underscore the need to reassess the efficacy of neo-chordae implantation relative to leaflet resection.

Concomitant Surgical Ablation in Paroxysmal vs Persistent Atrial Fibrillation During Mitral Surgery.

BACKGROUND: Despite prospective randomized evidence supporting concomitant treatment of Atrial Fibrillation (AF) during mitral valve (MV) surgery, variation in surgical management of AF remains. We sought to assess longitudinal outcomes following surgical treatment of persistent or paroxysmal AF during MV surgery in Medicare Beneficiaries. METHODS: All Medicare beneficiaries with a diagnosis of AF undergoing MV surgery (2018-2020) were evaluated. Patients were stratified by no AF treatment versus Left Atrial Appendage Obliteration (LAAO) alone versus LAAO and Surgical Ablation (SA+LAAO). Doubly robust risk-adjustment and subgroup analysis by persistent or paroxysmal AF were performed. RESULTS: A total of 7,517 patients with preoperative AF underwent MV surgery (32.1% no AF treatment, 23.1% LAAO alone, 44.7% SA+LAAO). After doubly robust risk-adjustment, AF treatment with SA+LAAO or LAAO alone was associated with lower 3-year readmission for stroke or bleeding. However, SA+LAAO was associated with reduced 3-year mortality, and readmission for AF or heart failure, compared to no AF treatment or LAAO alone. Compared to no AF treatment or LAAO alone, SA+LAAO was associated with lower composite endpoint of stroke or death at 3 years (HR 0.75 and HR 0.83, respectively). Subgroup analysis identified similar longitudinal benefits of SA+LAAO in patients with persistent or paroxysmal AF. CONCLUSIONS: In Medicare beneficiaries with AF undergoing MV surgery, SA+LAAO was associated with improved longitudinal outcomes compared to LAAO alone or no AF treatment in patients with paroxysmal or persistent AF. These contemporary real-world data further clarify the benefit of SA+LAAO during mitral valve surgery across all types of AF.

Structural Heart Imaging Using 3-Dimensional Intracardiac Echocardiography: JACC Cardiovascular Imaging Position Statement.

3-dimensional (3D) intracardiac echocardiography (ICE) is emerging as a promising complement and potential alternative to transesophageal echocardiography for imaging guidance in structural heart interventions. To establish standardized practices, our multidisciplinary expert position statement serves as a comprehensive guide for the appropriate indications and utilization of 3D-ICE in various structural heart procedures. The paper covers essential aspects such as the fundamentals of 3D-ICE imaging, basic views, and workflow recommendations specifically tailored for ICE-guided structural heart procedures, such as transeptal puncture, device closure of intracardiac structures, and transcatheter mitral and tricuspid valve interventions. Current challenges, future directions, and training requirements to ensure operator proficiency are also discussed, thereby promoting the safety and efficacy of this innovative imaging modality to support expanding its future clinical applications.

Mitral complex geometric changes aggravate mitral stenosis after transcatheter aortic valve replacement.

Severe aortic valve stenosis (AS) often coexists with mitral valve stenosis (MS). MS aggravation after transcatheter aortic valve replacement (TAVR) is common, and its etiology is multifactorial. We hypothesized that geometric changes in the mitral complex (mitral valvular and annular deformities) are adjunctive factors aggravating MS after TAVR, particularly in older adults with a smaller left ventricle (LV). This study aimed to evaluate the mitral complex geometric changes before and after TAVR and to assess the important predictors of MS aggravation after TAVR. This retrospective study enrolled consecutive adult patients who underwent TAVR and surgical AVR (SAVR) for severe AS. The mitral valve area (MVA), the angle between the anterior mitral valve leaflet (AMVL) and left ventricular outflow tract (LVOT), AMVL length, mitral annular diameter, presence of mitral annular calcification, and LV size were evaluated using transthoracic echocardiography. This study included 258 patients who underwent TAVR and SAVR. MVA index decreased from 2.3 ± 0.6 cm² to 1.9 ± 0.5 cm² in the TAVR group. The angle between the AMVL and LVOT was 56.3 ± 9.7° preoperatively and increased to 67.3 ± 11.5° after TAVR. In multivariate analysis, the most important predictive factors of MS aggravation after TAVR were a smaller mitral annular diameter, restricted AMVL mobility, and implantation depth (odds ratio: 4.5, 5.3,3.0; 95% confidence interval: 1.6-14, 1.9-17, 1.0-8.9; and p = 0.005, p = 0.001, p = 0.042, respectively). The reduction in MVA after TAVR was related to the restriction of AMVL opening, depth of implantation and narrowing of the mitral annulus.

Takotsubo syndrome after concomitant surgical ablation for the treatment of atrial fibrillation in patients undergoing minimally invasive mitral valve surgery: A clinical case and review.

INTRODUCTION AND IMPORTANCE: Takotsubo syndrome (TTS) is a reversible form of acute heart failure often triggered by physical or emotional stressors. Minimally invasive mitral valve surgery (MIMVS) has become a prevalent approach for treating mitral valve pathologies, yet its association with TTS remains underexplored. CASE PRESENTATION: We present the case of a female patient undergoing MIMVS with concomitant Maze ablation, who developed TTS postoperatively. Despite a normal coronary angiogram, transient coronary spasm due to an imbalance in autonomic nervous activity was considered. The patient exhibited preoperative risk factors including sequelae of cerebral infarction. CLINICAL DISCUSSION: Female patients undergoing MIMVS with preoperative risk factors such as cerebral infarction sequelae may be at increased risk of developing TTS postoperatively. CONCLUSION: The InterTAK Diagnostic score, in conjunction with the International Expert Consensus Document on Takotsubo Syndrome, aids in promptly diagnosing TTS and differentiating it from acute coronary syndrome. Further research is warranted to elucidate the relationship between MIMVS and TTS.

Mitral Annulus Disjunction in consecutive patients undergoing Cardiac Magnetic Resonance: where is the boundary between normality and disease?

BACKGROUND: The presence of mitral annulus disjunction (MAD) has been considered a high-risk feature for sudden cardiac death based on selected study populations. We aimed to assess the prevalence of MAD in consecutive patients undergoing clinically-indicated Cardiac Magnetic Resonance (CMR), its association with ventricular arrhythmias, Mitral Valve Prolapse (MVP), and other CMR features. METHODS: This single-center retrospective study included consecutive patients referred to CMR at our Institution between June 2021 and November 2021. The MAD was defined as a ≥1mm displacement between the left atrial wall-mitral valve leaflet junction and the left ventricular wall during end-systole. The MAD extent was defined as the maximum longitudinal displacement. Associates of MAD were evaluated at uni- and multi-variariable regression analysis. A study endpoint including (aborted) sudden cardiac death, unexplained syncope, and sustained ventricular tachycardia was evaluated at 12-month follow-up. RESULTS: Four-hundred-forty-one patients (55±18 years, 61% males) were included, and 29 (7%) had MVP. The prevalence of MAD ≥1mm, 4mm, and 6mm were 214 (49%), 63 (14%), and 15 (3%), respectively. Patients with MVP showed a higher prevalence of MAD greater than 1mm (90% vs. 46%; p<0.001), 4mm (48% vs. 12%; p<0.001), and 6mm (10% vs. 3%; p=0.03), and a greater MAD extent (4.2mm, 3.0-5.7mm vs. 2.8mm, 1.9-4.0mm; p<0.001) than patients without MVP. The MVP was the only morpho-functional abnormality associated with MAD at multivariable analysis (p<0.001). A high burden of ventricular ectopic beats at baseline Holter-ECG was associated with MAD ≥4mm and MAD extent (p<0.05). The presence of MAD ≥1mm (0.9% vs. 1.8%; p=0.46), MAD ≥4mm (1.6% vs. 1.3%; p=0.87), or MVP (3.5% vs. 1.2%; p=0.32) were not associated with the study endpoint, whereas patients with MAD ≥6mm showed a trend towards a higher likelihood of the study endpoint (6.7% vs. 1.2%; p=0.07). CONCLUSIONS: A MAD of limited entity was common in consecutive patients undergoing CMR. Patients with MVP showed higher prevalence and greater extent of MAD. Extended MAD was rarer and showed association with ventricular arrhythmias at baseline. The mid-term prognosis of MAD seems benign, however prospective studies are warranted to search for potential "malignant MAD extents" to improve patients' risk stratification.

Long-term outcomes following mitral valve replacement in children at heart center Leipzig: a 20-year analysis.

BACKGROUND: Although mitral valve repair is the preferred surgical strategy in children with mitral valve disease, there are cases of irreparable severe dysplastic valves that require mitral valve replacement. The aim of this study is to analyze long-term outcomes following mitral valve replacement in children in a tertiary referral center. METHODS: A total of 41 consecutive patients underwent mitral valve replacement between February 2001 and February 2021. The study data was prospectively collected and retrospectively analyzed. Primary outcomes were in-hospital mortality, long-term survival, and long-term freedom from reoperation. RESULTS: Median age at operation was 23 months (IQR 5-93), median weight was 11.3 kg (IQR 4.8-19.4 kg). One (2.4%) patient died within the first 30 postoperative days. In-hospital mortality was 4.9%. Four (9.8%) patients required re-exploration for bleeding, and 2 (4.9%) patients needed extracorporeal life support. Median follow-up was 11 years (IQR 11 months - 16 years). Long-term freedom from re-operation after 1, 5, 10 and 15 years was 97.1%, 93.7%, 61.8% and 42.5%, respectively. Long-term survival after 1, 5, 10 and 15 years was 89.9%, 87%, 87% and 80.8%, respectively. CONCLUSION: If MV repair is not feasible, MV replacement offers a good surgical alternative for pediatric patients with MV disease. It provides good early- and long-term outcomes.

Impact of Intraprocedural Mitral Regurgitation and Gradient Following Transcatheter Edge-to-Edge Repair for Primary Mitral Regurgitation.

BACKGROUND: The impact of intraprocedural results following transcatheter edge-to-edge repair (TEER) in primary mitral regurgitation (MR) is controversial. OBJECTIVES: This study sought to investigate the prognostic impact of intraprocedural residual mitral regurgitation (rMR) and mean mitral valve gradient (MPG) in patients with primary MR undergoing TEER. METHODS: The PRIME-MR (Outcomes of Patients Treated With Mitral Transcatheter Edge-to-Edge Repair for Primary Mitral Regurgitation) registry included consecutive patients with primary MR undergoing TEER from 2008 to 2022 at 27 international sites. Clinical outcomes were assessed according to intraprocedural rMR and mean MPG. Patients were categorized according to rMR (optimal result: ≤1+, suboptimal result: ≥2+) and MPG (low gradient: ≤5 mm Hg, high gradient: > 5 mm Hg). The prognostic impact of rMR and MPG was evaluated in a Cox regression analysis. The primary endpoint was 2-year all-cause mortality or heart failure hospitalization. RESULTS: Intraprocedural rMR and mean MPG were available in 1,509 patients (median age = 82 years [Q1-Q3: 76.0-86.0 years], 55.1% male). Kaplan-Meier analysis according to rMR severity showed significant differences for the primary endpoint between rMR ≤1+ (29.1%), 2+ (41.7%), and ≥3+ (58.0%; P < 0.001), whereas there was no difference between patients with a low (32.4%) and high gradient (42.1%; P = 0.12). An optimal result/low gradient was achieved in most patients (n = 1,039). The worst outcomes were observed in patients with a suboptimal result/high gradient. After adjustment, rMR ≥2+ was independently linked to the primary endpoint (HR: 1.87; 95% CI: 1.32-2.65; P < 0.001), whereas MPG >5 mm Hg was not (HR: 0.78; 95% CI: 0.47-1.31; P = 0.35). CONCLUSIONS: Intraprocedural rMR but not MPG independently predicted clinical outcomes following TEER for primary MR. When performing TEER in primary MR, optimal MR reduction seems to outweigh the impact of high transvalvular gradients.

FOXC1 and FOXC2 Ablation Causes Abnormal Valvular Endothelial Cell Junctions and Lymphatic Vessel Formation in Myxomatous Mitral Valve Degeneration.

BACKGROUND: Mitral valve (MV) disease including myxomatous degeneration is the most common form of valvular heart disease with an age-dependent frequency. Genetic evidence indicates that mutations of the transcription factor FOXC1 are associated with MV defects, including MV regurgitation. In this study, we sought to determine whether murine Foxc1 and its closely related factor, Foxc2, are required in valvular endothelial cells (VECs) for the maintenance of MV leaflets, including VEC junctions and the stratified trilaminar ECM (extracellular matrix). METHODS: Adult mice carrying tamoxifen-inducible, vascular endothelial cell (EC), and lymphatic EC-specific, compound Foxc1;Foxc2 mutations (ie, EC-Foxc-DKO and lymphatic EC-Foxc-DKO mice, respectively) were used to study the function of Foxc1 and Foxc2 in the maintenance of MVs. The EC and lymphatic EC mutations of Foxc1/c2 were induced at 7 to 8 weeks of age by tamoxifen treatment, and abnormalities in the MVs of these mutant mice were assessed via whole-mount immunostaining, immunohistochemistry/RNAscope, Movat pentachrome/Masson Trichrome staining, and Evans blue injection. RESULTS: EC deletions of Foxc1 and Foxc2 in mice resulted in abnormally extended and thicker MVs by causing defects in the regulation of ECM organization with increased proteoglycan and decreased collagen. Notably, reticular adherens junctions were found in VECs of control MV leaflets, and these reticular structures were severely disrupted in EC-Foxc-DKO mice. PROX1 (prospero homeobox protein 1), a key regulator in a subset of VECs on the fibrosa side of MVs, was downregulated in EC-Foxc1/c2 mutant VECs. Furthermore, we determined the precise location of lymphatic vessels in murine MVs, and these lymphatic vessels were aberrantly expanded and dysfunctional in EC-Foxc1/c2 mutant MVs. Lymphatic EC deletion of Foxc1/c2 also resulted in similar structural/ECM abnormalities as seen in EC-Foxc1/c2 mutant MVs. CONCLUSIONS: Our results indicate that Foxc1 and Foxc2 are required for maintaining the integrity of the MV, including VEC junctions, ECM organization, and lymphatic vessel formation/function to prevent myxomatous MV degeneration.

Dysplastic Mitral Valve in Costello Syndrome.

Costello syndrome is an autosomal dominant condition caused by variants in the HRAS gene. Cardiac presentation includes valvular disease (usually valvar pulmonary stenosis), arrhythmias, and hypertrophic cardiomyopathy. To our knowledge, this is the first such report of dysplastic mitral valve associated with Costello syndrome.

Quantified planar collagen distribution in healthy and degenerative mitral valve: biomechanical and clinical implications.

Degenerative mitral valve disease is a common valvular disease with two arguably distinct phenotypes: fibroelastic deficiency and Barlow's disease. These phenotypes significantly alter the microstructures of the leaflets, particularly the collagen fibers, which are the main mechanical load carriers. The predominant method of investigation is histological sections. However, the sections are cut transmurally and provide a lateral view of the microstructure of the leaflet, while the mechanics and function are determined by the planar arrangement of the collagen fibers. This study, for the first time, quantitatively examined planar collagen distribution quantitatively in health and disease using second harmonic generation microscopy throughout the thickness of the mitral valve leaflets. Twenty diseased samples from eighteen patients and six control samples were included in this study. Healthy tissue had highly aligned collagen fibers. In fibroelastic deficiency they are less aligned and in Barlow's disease they are completely dispersed. In both diseases, collagen fibers have two preferred orientations, which, in contrast to the almost constant one orientation in healthy tissues, also vary across the thickness. The results indicate altered in vivo mechanical stresses and strains on the mitral valve leaflets as a result of disease-related collagen remodeling, which in turn triggers further remodeling.

Outcomes of maze procedure and mitral valve surgery in atrial functional mitral regurgitation: a retrospective study.

BACKGROUND: Atrial functional mitral regurgitation (AFMR) is a newly discovered condition associated with longstanding atrial fibrillation. This retrospective study aimed to analyze the outcomes of the maze procedure and mitral regurgitation (MR) surgery in AFMR and atrial fibrillation in comparison with those in degenerative MR (DMR). METHODS: Patients who underwent mitral valve repair/replacement with a maze procedure at a hospital (July 2012-August 2021) were included. We excluded patients aged below 18 years undergoing concomitant coronary artery bypass grafting or atrial septal defect repair and those with MR etiology other than ARMR or DMR. RESULTS: We included 35 patients with AFMR and 50 patients with DMR. Patient characteristics and postoperative outcomes were not significantly different between the two groups. Long-term outcomes revealed no significant differences in the ratio of cardiac mortality, stroke, or hospital readmission. However, after the maze procedure, the sinus rhythm restoration rate was significantly lower (62% vs. 28.5%, p < 0.001), a junctional rhythm state (p < 0.001) and permanent pacemaker insertion for sick sinus syndrome (SSS) (p = 0.03) were significantly more common in AFMR than DMR. On postoperative transthoracic echocardiography (TTE), the pulmonary artery systolic pressure was significantly less decreased in the AFMR group than in the DMR group compared with that on preoperative TTE (p = 0.04). CONCLUSIONS: AFMR showed excellent mitral valve surgery outcomes, similar to DMR, but had a significantly higher risk of pacemaker insertion for SSS after the maze procedure.

Comparison of maternal and fetal outcomes in mothers with non-congenital mitral valve stenosis and healthy control.

Background: Physiological changes during pregnancy cause complications in mothers with mitral stenosis and their infants. This study was designed to assess maternal and fetal pregnancy outcomes in women with rheumatic mitral valve stenosis and compare them with the control group. Materials and methods: This study is a case-control study on 153 pregnant women, including 51 with mitral stenosis (MS) and 102 without MS as the control group, between 2007-2022. For each studied patient, two control participants were selected and matched in residence, age, and year of pregnancy. SPSS version 22 was used for data analysis. Results: The mean age was 31.7 ± 4.6 years in cases and 31.6 ± 4.7 in the healthy controls. Demographic variables were not significantly different between the case and control groups. The rate of stillbirth (5.9% vs. 0.0%), %), NICU admission (13.7% vs. 2.0%), and IUGR (5.9% vs. 0.0%) were higher in the fetal case group compared with the control group. On the other hand, maternal outcomes, including pulmonary edema (13.7% vs. 0.0%), ICU admission (23.5% vs. 0.0%), limb edema (15.7% vs. 0.0%), dyspnea (37.3% vs. 0.0%), pulmonary hypertension (9.8% vs. 0.0%), palpitations (21.1% vs. 0.0%) and hospital admission during pregnancy (37.2% vs. 4.9%) were statistically more common in the case groups. Conclusions: Pregnancy is associated with significant fetomaternal morbidities in women with mitral valve heart disease. So they need a multidisciplinary approach in preconception and antenatal care.