Epidemiology and pathophysiology of mitral valve prolapse: new insights into disease progression, genetics, and molecular basis

Comprehensive genetic analysis based on multi - omics reveals novel therapeutic targets for mitral valve prolapse and drug molecular dynamics simulation

OBJECTIVE

Mitral valve prolapse (MVP), the most prevalent primary valvular disease, serves as a direct risk factor for multiple cardiovascular disorders and exhibits a high prevalence in the general population. As no specific pharmacological therapies currently exist for MVP, the identification of precise therapeutic targets is imperative.

METHOD

We conducted comprehensive causal genetic inference by integrating genetic data from expression quantitative trait loci (eQTL) and genome-wide association studies (GWAS). Analytical approaches included Mendelian Randomization (MR), colocalization analysis, Summary-data-based Mendelian Randomization (SMR), Linkage Disequilibrium Score Regression (LDSC), and High-Definition Likelihood (HDL) analysis. Protein quantitative trait loci (pQTL) were utilized to validate gene expression. Replication analyses were performed using additional exposure datasets. Methylation quantitative trait loci (mQTL) were employed to elucidate regulatory roles of methylation sites on genes and disease pathogenesis. Phenome-Wide Association Study (PheWAS) was conducted to predict potential adverse effects of gene-targeted therapies. Drug candidates targeting identified genes were predicted via the Drug Signature Database (DSigDB) and validated through molecular docking. Core targets were identified using the STRING database, followed by molecular dynamics simulations.

RESULT

Two-sample MR analysis showed that genetically predicted 302 genes had positive or negative causal relationships with MVP. Colocalization analysis indicated that 9 genes had a posterior probability greater than 0.75. Subsequent SMR analysis excluded the gene GAPVD1. HDL analysis showed that except for the gene PTPN1, the remaining 7 genes were all significantly genetically associated with MVP, and LDSC analysis further showed that only NMB was associated with MVP. Validation using pQTL data confirmed that increased NMB protein expression reduced the risk of MVP. Replication analysis further verified this conclusion. In addition, SMR analysis of methylation sites for 8 genes indicated that multiple methylation sites played a key role in gene regulation of mitral valve prolapse. PheWAS results showed that targeted therapy for 8 genes did not detect other causal associations at the genome-wide significance level. Molecular docking showed that quercetin had good binding ability with 8 target genes. The STRING database identified 3 core target proteins, and molecular dynamics simulations further verified the binding ability of quercetin with core target proteins.

CONCLUSION

This study successfully predicted the potential of multiple druggable genes as effective therapeutic targets for MVP through genetic methods, validated the potential of quercetin as a drug, and provided new ideas for drug treatment strategies for MVP.

Deep learning-based post hoc denoising for 3D volume-rendered cardiac CT in mitral valve prolapse

We hypothesized that deep learning-based post hoc denoising could improve the quality of cardiac CT for the 3D volume-rendered (VR) imaging of mitral valve (MV) prolapse. We aimed to evaluate the quality of denoised 3D VR images for visualizing MV prolapse and assess their diagnostic performance and efficiency. We retrospectively reviewed the cardiac CTs of consecutive patients who underwent MV repair in 2023. The original images were iteratively reconstructed and denoised with a residual dense network. 3DVR images of the "surgeon's view" were created with blood chamber transparency to display the MV leaflets. We compared the 3DVR image quality between the original and denoised images with a 100-point scoring system. Diagnostic confidence for prolapse was evaluated across eight MV segments: A1-3, P1-3, and the anterior and posterior commissures. Surgical findings were used as the reference to assess diagnostic ability with the area under curve (AUC). The interpretation time for the denoised 3DVR images was compared with that for multiplanar reformat images. For fifty patients (median age 64 years, 30 males), denoising the 3DVR images significantly improved their image quality scores from 50 to 76 (P <.001). The AUC in identifying MV prolapse improved from 0.91 (95% CI 0.87-0.95) to 0.94 (95% CI 0.91-0.98) (P =.009). The denoised 3DVR images were interpreted five-times faster than the multiplanar reformat images (P <.001). Deep learning-based denoising enhanced the quality of 3DVR imaging of the MV, improving the performance and efficiency in detecting MV prolapse on cardiac CT.

Global Prevalence of Mitral Regurgitation: A Systematic Review and Meta-Analysis of Population-Based Studies

Background/Objectives: Mitral regurgitation (MR) is the most common left heart valve disease, but its exact prevalence remains uncertain. To estimate the prevalence of MR we conducted a systematic review and meta-analysis of population-based studies. Methods: We searched the Medline/PubMed, Embase, and Scopus databases, in January 2023, for studies reporting or allowing for the calculation of the prevalence of moderate-to-severe MR in the general population. Eligible studies included those using echocardiography or primary care databases from countries with universal healthcare. Studies where echocardiography was performed for medical indications were excluded. Random-effects meta-analysis was used to calculate the pooled estimates. Subgroup and meta-regression analyses were employed to investigate the reasons for heterogeneity. Mixed-model multivariable meta-regression was used to estimate age- and sex-specific prevalence. Results: After screening 13,847 records, we identified 20 eligible studies (22 study populations) including 6,036,691 individuals. The global prevalence of moderate-to-severe MR was 0.67% (95% CI, 0.33-1.11). Prevalence increased greatly with age, and it was estimated to be approximately 0.63% (0.25-1.16) at age 50, 2.85% (1.96-3.90) at 70, and 6.45% (4.17-9.16) by 90 years. North America showed the largest crude prevalence (1.11%; 0.52-1.88), followed by Europe (0.60%; 0.34-0.92), Asia (0.24%; 0.00-0.92), and Africa (0.16%; 0.03-0.37). Differences in prevalence by geographic region and ethnic group were primarily attributable to population age. Prevalence did not differ by sex, study year, or diagnostic criteria. Conclusions: Moderate-to-severe MR is a prevalent condition, particularly among elderly people. With rising life expectancy worldwide, ensuring universal access to interventions will be vital to reduce morbidity and mortality.

Transcatheter Repair in Posterior, Anterior, and Bileaflet Mitral Valve Disease: 1-Year Results From EXPANDed

BACKGROUND

Treating anterior and bileaflet mitral valve disease in patients with primary or degenerative mitral regurgitation (DMR) is considered more challenging than posterior leaflet repair.

OBJECTIVES

The aim of this analysis was to evaluate the impact of anterior, posterior, or bileaflet disease on outcomes following mitral transcatheter edge-to-edge repair (M-TEER) in the EXPANDed studies.

METHODS

EXPANDed is a pooled, patient-level analysis of subjects undergoing M-TEER with the MitraClip G3 or G4 system as part of the contemporary EXPAND and EXPAND G4 studies. Subjects with DMR were categorized according to echocardiography core laboratory-assessed prolapse or flail location into posterior (prolapse or flail at P1, P2, and/or P3), anterior (prolapse or flail at A1, A2, and/or A3) or bileaflet disease (prolapse or flail at any combination of A1, A2, and A3 and P1, P2, and P3). Key outcomes assessed included procedural outcomes, 30-day major adverse events, and 1-year mitral regurgitation (MR) severity.

RESULTS

Of 2,205 subjects in EXPANDed, 556 had echocardiography core laboratory-assessed DMR and prolapse or flail location. A total of 389 had posterior, 106 had anterior, and 61 had bileaflet disease. All groups experienced low device and procedure times with high procedural success rates (defined as discharge MR ≤2+). Thirty-day major adverse events rates were low across all groups (posterior, 4.4% [17 of 388]; anterior, 3.8% [4 of 105]; bileaflet, 6.6% [4 of 61]; P = 0.65). Through 1 year, all groups showed a significant reduction in MR severity from baseline (MR ≤1+ posterior, 82% [179 of 219]; anterior, 93% [53 of 57]; bileaflet, 97% [28 of 29]).

CONCLUSIONS

Results from the EXPANDed studies demonstrate that subjects with DMR treated with M-TEER experienced significant improvements in outcomes, regardless of the location of prolapse or flail.

Multimodality Imaging of Arrhythmic Risk in Mitral Valve Prolapse

Mitral valve prolapse (MVP) affects 2% to 3% of the general population and is typically benign. However, a subset of patients may develop arrhythmic complications, including sudden cardiac arrest and sudden cardiac death. This review explores the critical role of multimodality imaging in risk stratification for arrhythmic MVP, emphasizing high-risk features such as bileaflet involvement, mitral annular disjunction, the double-peak strain pattern, mechanical dispersion, and myocardial fibrosis. Echocardiography remains the first-line imaging tool for MVP diagnosis, enabling detailed assessment of leaflet morphology, mitral annular disjunction, and mitral regurgitation quantification. Speckle tracking provides insights into abnormal valvular-myocardial mechanics as a potential arrhythmogenic mechanism in MVP. Cardiac magnetic resonance (CMR) offers detailed myocardial tissue characterization through assessment of replacement and interstitial fibrosis using late gadolinium enhancement and T1 mapping/extracellular volume fraction, respectively. Hybrid Positron Emission Tomography/CMR highlights the role of inflammation, which may coexist with fibrosis, in explaining the presence of malignant arrhythmias even with relatively limited fibrosis. The assessment of diffuse fibrosis and inflammation by CMR and Positron Emission Tomography/CMR is particularly valuable in patients without classic imaging risk factors such as mitral annular disjunction, severe mitral regurgitation, or replacement fibrosis. We propose an algorithm integrating clinical, rhythmic, echocardiographic, CMR, and Positron Emission Tomography/CMR parameters for arrhythmic risk stratification and management. Although multimodality imaging is essential for comprehensive risk assessment, most available parameters have not yet been validated in prospective studies nor linked directly to mortality. Consequently, these imaging findings should be interpreted alongside the presence of complex ventricular ectopy, which remains the most robust predictor of mortality in arrhythmic MVP.

Advanced Silicon Modeling of Native Mitral Valve Physiology: A New Standard for Device and Procedure Testing

Mitral valve regurgitation is among the most prevalent valvular heart diseases and increases with age. Percutaneous therapy has emerged for the management of mitral regurgitation in high surgical risk patients. However, the long-term consequences of these interventions are still not fully understood due to their novelty and the difficulty of developing a strategy specific to the patient's anatomy and/or pathology. To optimize these outcomes, an in vitro patient-specific approach could provide important insights for the most suitable strategy to use according to the patient profile. To ensure the reliability of this in vitro approach, the aim of this study was to reproduce the physiological behavior of the healthy native mitral valve for future applications. To do so, different silicon combinations reproducing the physiological anatomy of a healthy mitral valve were developed and tested under physiological hemodynamic conditions in a cardiac simulator. The hemodynamic and biomechanical behaviors of each mitral valve model were analyzed and compared to the physiological values provided in the literature. This study identified EcoFlex 00-50 and DragonSkin 10 (Smooth-On Inc., Easton, PA, USA) as the optimal silicon combination resulting in physiological strain values and hemodynamic parameters. These findings could be useful for future patient-specific applications, helping in the optimization of percutaneous mitral valve therapy.

Accuracy of noninvasive screening exercise tests for detecting coronary artery disease in symptomatic patients with mitral valve prolapse: a systematic review

BACKGROUND

Since the 1970s, only a few studies have evaluated the accuracy of noninvasive screening exercise tests for detecting coronary artery disease (CAD) in symptomatic individuals with mitral valve prolapse (MVP). The present systematic review has been designed to summarize the main findings of these studies and to assess the overall pooled estimates of sensivity and specificity of exercise ECG, exercise myocardial perfusion scintigraphy (MPS) and exercise stress echocardiography (ESE) in diagnosing CAD among MVP individuals.

METHODS

All studies examining the specificity and sensitivity of exercise ECG and/or exercise MPS and/or ESE in detecting obstructive CAD in symptomatic MVP patients, selected from PubMed and EMBASE databases, were included. There was no limitation of time period. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies.

RESULTS

The full texts of 11 studies with 840 MVP individuals were analyzed. True obstructive CAD was documented in 11.1% of MVP individuals (range 0-31.2%). When used in MVP patients with suspected CAD, exercise ECG, exercise MPS and ESE showed a pooled specificity of 61.9% (range 25-91.7%), 82.3% (range 25-100%) and 89% (range 80.5-97.6%), respectively, and a pooled sensitivity of 80% (range 50-100%), 96.7% (range 90-100%) and 91% (range 82-100%), respectively. The pooled positive predictive value was 33.2% (range 23.1-44.8%) for exercise ECG, 100% for exercise MPS and 80.2% (range 75.8-84.6%) for ESE, whereas the pooled negative predictive value was 80% (range 50-100%) for exercise ECG, 97% for exercise MPS and 99% (range 97.6-100%) for ESE.

CONCLUSION

ESE appears to be the first-choice screening method for CAD detection in symptomatic MVP individuals. It allows true CAD in symptomatic MVP individuals with false-positive exercise ECG results to be ruled out, without ionizing radiation exposure.

The Prevalence, Pathophysiological Role and Determinants of Mitral Annular Disjunction Among Patients with Mitral Valve Prolapse: A Systematic Review

Background: Over the last two decades, a number of imaging studies have evaluated the characteristics and clinical implications of mitral annular disjunction (MAD) among patients with mitral valve prolapse (MVP). The present systematic review has been primarily designed to summarize the main findings of these studies and to examine the overall impact of MAD in MVP patients. Methods: All imaging studies assessing the prevalence, pathophysiological role and determinants of MAD in MVP individuals, selected from the PubMed and EMBASE databases, were included. There was no limitation in terms of time period. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results: The full texts of 23 studies on 7718 MVP individuals were analyzed. The overall pooled prevalence of MAD in MVP individuals was 40% (range 5.4-90%). When considering the different imaging modalities for assessing MAD, the average MAD prevalence was 20% for cardiac computed tomography studies, 31.3% for transthoracic echocardiography (TTE) studies, 44.7% for transesophageal echocardiography studies and 47% for cardiac magnetic resonance studies. MAD presence was more commonly associated with female sex, young age, narrow antero-posterior thoracic diameter, symptoms of palpitations and syncope, T-wave inversion in inferolateral leads and frequent and/or complex ventricular arrhythmias (VAs) on electrocardiogram, myxomatous leaflets, bileaflet prolapse, larger mitral valve annulus and non-severe mitral regurgitation on TTE. A total of 12 studies (52.2%) provided follow-up data. Over a median follow-up time of 3.9 yrs (range 1-10.3 yrs), MVP individuals with MAD showed increased risk of clinical arrhythmic events, no difference in survival rate and good surgical outcomes. Conclusions: MAD was present in more than one-third of MVP patients, with a wide range of variability depending on the specific imaging method used for assessing MAD presence and on a nonunivocal MAD definition, with a possible overestimation due to Pseudo-MAD rather than True-MAD measurement. A multimodality imaging approach comprehensive of noninvasive chest shape assessment might improve MAD detection among MVP individuals. It appears that careful serial monitoring for VAs should be mandatory for MAD patients.

Gender specific echocardiographic prevalence of valvular stenosis and regurgitations in a large inpatient database of 24,265 patients

INTRODUCTION

Prevalence of different valvular pathologies has not been reported in female and male patients in large population-based studies. The goal of this study was to report the gender-specific prevalence of various valvular pathologies.

METHODS

We retrospectively analyzed 24,265 echocardiograms performed between 1984 and 1998. The prevalence of mitral regurgitation (MR) aortic valve regurgitation (AR) and stenosis (AS), and tricuspid regurgitation (TR) were calculated in female and male patients.

RESULTS

Echocardiograms were performed on 12,926 (53%) female and 11,339 (47%) male patients. Gender-specific echocardiographic prevalence of different valvular abnormalities was as follows: Prevalence of mitral regurgitations was similar in women and men (25% vs 24.7%). Aortic regurgitation was higher in males (5.5 vs 14.9%, P < 0.001). Aortic stenosis prevalence was similar between both genders (2.1 vs 2.3%). Tricuspid valve regurgitations were slightly higher in females (18.5 vs 16.7%, P < 0.001).

CONCLUSION

In this study, we found a significantly higher prevalence of tricuspid valve regurgitation in women. Aortic regurgitation was more prevalent in men. Aortic stenosis and mitral regurgitation had similar prevalence in both genders.

Mitral valve prolapse in sudden cardiac arrest survivors: Coincidence or causal relationship?

BACKGROUND

Sudden cardiac arrest (SCA) risk stratification in patients with mitral valve prolapse (MVP) may be complicated by other potential causes of arrhythmia.

OBJECTIVE

We aimed to characterize SCA survivors with isolated MVP (iMVP) and non-isolated MVP (non-iMVP) and to assess their long-term follow-up.

METHODS

This ambispective study included 75 patients with MVP who experienced SCA and were treated in our center between 2009 and 2024. They were divided into 3 groups according to probability of relation between SCA and comorbidities. The control group comprised 112 participants with MVP but without a history of SCA. We analyzed all available electrocardiograms, Holter electrocardiography monitoring, and echocardiograms, including longitudinal strain. A novel parameter, the systolic atrial-directed notch (SADN), was tested.

RESULTS

SCA survivors with iMVP (n = 28) had higher prevalence of mitral annular disjunction (80% vs 35.7%; P = .006), Pickelhaube sign (60% vs 8.3%; P = .008), and SADN >2 mm (69.6% vs 14.3%; P = .001) as well as higher absolute longitudinal strain values in basal and mid segments of the inferior and inferolateral wall than patients with SCA and non-iMVP without other defined structural heart diseases (n = 14). The differences were also observed in comparison to the control group. The cumulative incidence of appropriate implantable cardioverter-defibrillator shocks within 6 years was 62% in patients with iMVP and 23% in the group with non-iMVP without other defined structural heart diseases.

CONCLUSION

Echocardiographic findings such as mitral annular disjunction, SADN, Pickelhaube sign, and increased segmental strain may be useful in the assessment of the relation between SCA and MVP. Malignant arrhythmias often recur in SCA survivors with iMVP.

Evaluation of the clinical features of an outpatient cohort with Marfan syndrome

Marfan syndrome is a connective tissue disease with autosomal dominant inheritance and variable clinical presentation. The main clinical manifestations recognition could contribute to early diagnosis and cardiovascular complication prevention. We aimed to evaluate the clinical profile of a Marfan syndrome outpatient cohort.

METHODS

Retrospective cross-sectional study was carried out with outpatients over 12 years of age whose electronic medical records contained the clinical information and complementary exams necessary for study inclusion. Data were analyzed using descriptive statistics and comparisons were performed using student's t-test and chi-square or Fisher's exact test. P-values<0.05 were considered statistically significant.

RESULTS

75 patients (29.5 ± 13.4 years) were included and 43(57 %) were female. Positive family history for the syndrome was observed in 55(73 %) patients and ectopia lentis in 37(49 %). Positive systemic score (≥7) was identified in 60(80 %) individuals and the most frequent score components were: skin striae in 64(85 %), scoliosis in 59(79 %), wrist and thumb sign in 45(60 %), moderate or severe myopia in 43(57 %) and plain flat foot in 40(53 %). Cardiovascular symptoms occurred in 17(23 %) patients: dyspnea in 10(13 %) and palpitations in 6(8 %). Mitral valve prolapse was observed in 32(43 %) participants and aortic root dilation (z-score ≥ 2) in 53(71 %), without significant difference between the groups with or without these alterations concerning sex, age, or symptom presence.

CONCLUSION

Clinical profile of a Marfan syndrome outpatient cohort includes adolescents and young adults, most without cardiovascular symptoms and with a high incidence of skeletal, ophthalmological, and cardiovascular involvement. Recognizing these clinical signs could contribute to early disease diagnosis in the general population.

Inheritance of Imaging Parameters of Arrhythmic Risk in Mitral Valve Prolapse: A Pedigree Study

BACKGROUND

A subset of patients with mitral valve prolapse (MVP), a highly heritable condition, experience sudden cardiac arrest (SCA) or sudden cardiac death (SCD). However, the inheritance of phenotypic imaging features of arrhythmic MVP remains unknown.

METHODS

We recruited 23 MVP probands, including 9 with SCA/SCD and 14 with frequent/complex ventricular ectopy. Participants underwent interviews, 2-dimensional and speckle-tracking echocardiography, and 48-hour Holter/event monitoring. Each individual was categorized as having a normal mitral valve, MVP, or borderline MVP. We assessed mitral annular disjunction, curling, global longitudinal strain, segmental peak longitudinal strain, electrical/mechanical dispersion, and the postsystolic shortening index in family members and unrelated healthy controls.

RESULTS

We enrolled 23 pedigrees (14 extended pedigrees, 4 trios, and 5 duos) with a total of 121 participants (mean age 45 years, 50% women). Multigenerational SCA/SCD occurred in 2 of 14 extended pedigrees (14%) with an SCA/SCD proband. Mitral annular disjunction was present in 2 generations among 3 families (13%) and absent in 3 of 9 (33%) SCA/SCD cases. Compared with nonarrhythmic cases, arrhythmic MVP cases had more bileaflet involvement, mitral annular disjunction, curling, and abnormal valvular-myocardial mechanics, as expressed by a higher mid-inferior/inferolateral postsystolic shortening index (P<0.05). Among arrhythmic MVP cases, those with SCA had the highest mechanical dispersion (P=0.04). Family members with normal valves had lower global longitudinal strain and greater mechanical dispersion compared with nonpedigree controls (both P<0.05).

CONCLUSIONS

In the context of familial MVP, SCA/SCD is rarely observed in multiple generations and is not consistently linked to mitral annular disjunction. Instead, SCA may result from combination of abnormal valvular-myocardial mechanics and a substrate of increased mechanical/electrical dispersion. Family members with normal mitral valves also exhibit mildly abnormal global strain parameters, suggesting an underlying myopathy independent of MVP expression. Future studies are needed to determine whether SCA/SCD in MVP requires the concomitant presence of abnormal mechanics and a primary genetic myopathy.

Revolutionizing cardiovascular care: the power of histotripsy

Histotripsy, an innovative ultrasonic technique, is poised to transform the landscape of cardiovascular disease management. This review explores the multifaceted applications of histotripsy across various domains of cardiovascular medicine. In thrombolysis, histotripsy presents a non-invasive, drug-free, and precise method for recanalizing blood vessels obstructed by clots, minimizing the risk of vessel damage and embolism. Additionally, histotripsy showcases its potential in congenital heart defect management, offering a promising alternative to invasive procedures by creating intracardiac communications noninvasively. For patients with calcified aortic stenosis, histotripsy demonstrates its effectiveness in softening calcified bioprosthetic valves, potentially revolutionizing valve interventions. In the realm of arrhythmias, histotripsy could play an important role in scar-based ventricular tachycardia ablation, eliminating channel-like isthmuses of slowly conducting myocardium. Histotripsy`s potential applications also extend to structural heart interventions, enabling the safe sectioning of basal chordae and potentially addressing mitral regurgitation. Furthermore, it showcases its versatility by safely generating ventricular septal defects, providing a non-invasive means of creating intracardiac communications in neonates with congenital heart disease. Yet, most supporting studies are in-vitro or animal studies and there are possible challenges in translating experimental data on cardiac histotripsy to the clinical level. As histotripsy continues to evolve and mature, its remarkable potential in cardiovascular disease management holds promise for improving patient outcomes and reducing the burden of invasive procedures in the field of cardiology.

Prevalence of Mitral Valve Prolapse Among Individuals with Pectus Excavatum: A Systematic Review and Meta-Analysis

Background: During the last decades, a small number of studies reported a wide range of variability in the estimated prevalence of mitral valve prolapse (MVP) among individuals with pectus excavatum (PE). The present systematic review and meta-analysis has been primarily designed to summarize the main findings of these studies and to estimate the overall prevalence of MVP among PE individuals. Methods: All imaging studies assessing the prevalence of MVP in PE individuals vs. healthy controls, selected from PubMed and EMBASE databases, were included. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment of Case-Control Studies. Events (presence of MVP) and nonevents (absence of MVP) in PE individuals and control groups were recorded. The main outcome was the measure of odds ratio (OR) for MVP presence pooled with 95% confidence intervals, using a fixed-effects model. Results: The full texts of eight studies with 303 PE patients (mean age 25.7 yrs) and 498 healthy controls (mean age 31 yrs) were analyzed. Three studies assessed MVP prevalence in children and early adolescents, whereas the remaining five studies examined PE adults. The prevalence of MVP in PE individuals and healthy controls was 40.6% and 12.8%, respectively. In the pooled sample, the OR for MVP presence was significantly higher in PE individuals compared to controls (OR = 5.80, 95%CI = 3.83-8.78, Z = 8.30, p < 0.001). Subgroup analysis revealed that MVP prevalence was approximately three-fold higher among PE children and early adolescents compared with PE adults. Overall, high consistency was observed in the pooled effect sizes, due to the low statistical heterogeneity among the included studies (I2 = 22.7%, p = 0.25). Egger's test for a regression intercept gave a p-value of 0.07, indicating no publication bias. The sensitivity analysis supported the robustness of the results. Conclusions: PE individuals are nearly six times more likely to have MVP than controls. MVP prevalence is three-fold higher in PE individuals during childhood and early adolescence, compared to PE adults. Given the strong association between MVP and PE, MVP should be suspected in all individuals with anterior chest wall deformity.

Risk of Recurrent and Frequent Preterm Birth Among Women With Mitral Valve Prolapse: A Systematic Review and Meta-Analysis

Preterm delivery remains a prominent problem in obstetrics with significant adverse implications for both mothers and the offspring. The incidence of mitral valve prolapse (MVP) in women of childbearing age has raised concerns about pregnancy and pregnancy connotations. The objective of this systematic review and meta-analysis is to help in understanding the plausibility of the association between MVP and preterm birth in women with a history of frequent deliveries. Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we searched the databases, including PubMed, Embase, Cochrane Library, Web of Science, and Scopus, for studies published in the period 1999 through 2024. Inclusion criteria consisted of studies such as cohort, cross-sectional, and case-control studies related to women diagnosed with MVP out of a total number of 1,029 articles found. Overall, a total of 19 studies were included in this review, with 3 of which were considered for further meta-analysis. It was revealed in the analysis that there was an association between MVP and preterm delivery when the severity of MVP was at Types II and III. The evidence also underscores the importance of both follow-up and preemptive measures among women suffering from MV prolapse for improved maternal and neonatal outcomes. The average Z-value (4.47) and p-value (0.00) for the test for overall effect size indicate the presence of a high correlation between MVP and premature delivery, suggesting satisfactory statistics on the association. The findings do indicate that MVP is a risk factor for preterm delivery (pooled ES = 0.24, 95% CI = 0.14 to 0.35, P <0.001).

Echocardiographic Assessment of Mitral Valve Prolapse Prevalence before and after the Year 1999: A Systematic Review

Background: Over the last five decades, a fair number of echocardiographic studies have evaluated the prevalence of mitral valve prolapse (MVP) in various cohorts of individuals, including heterogeneous study populations. The present systematic review has been primarily designed to summarize the main findings of these studies and to estimate the overall MVP prevalence in the general community. Methods: All echocardiographic studies assessing the MVP prevalence in various cohorts of individuals, selected from PubMed and EMBASE databases, were included. There was no limitation of time period. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results: The full texts of 21 studies with 1354 MVP individuals out of 63,723 participants were analyzed. The overall pooled prevalence of MVP was 4.9% (range of 0.6-21%). When dividing the studies in two groups according to the echocardiographic criteria used for MVP diagnosis (less specific old criteria or more specific new criteria, respectively), the estimated pooled prevalence of MVP was 7.8% (range of 2-21%) for the older studies (performed between 1976 and 1998) and 2.2% (range of 0.6-4.2%) for the more recent ones (conducted between 1999 and 2021). Potential selection bias, hospital- or referral-based series, and the use of less specific echocardiographic criteria for MVP diagnosis have been indicated as the main reasons for the higher MVP prevalence detected by the older studies. MVP was commonly associated with a narrow antero-posterior thoracic diameter, isolated ventricular premature beats and nonspecific ST-T-wave abnormalities on a resting electrocardiogram, mild-to-moderate mitral regurgitation (MR), the reduced probability of obstructive coronary artery disease, and a low frequency of serious complications, such as severe MR, infective endocarditis, heart failure, stroke, and atrial fibrillation. Conclusions: MVP has a low prevalence in the general population, regardless of age, gender, and ethnicity, and is associated with a good outcome.

Cardiovascular, autonomic symptoms and quality of life in children with hypermobile Ehlers-Danlos syndrome

Objectives

Hypermobile Ehlers-Danlos syndrome is a connective tissue disorder characterized by joint hypermobility and other systemic manifestations. Cardiovascular, autonomic symptoms and dysautonomia are frequently reported in adults with hypermobile Ehlers-Danlos syndrome and have been shown to have a negative impact on quality of life. However, there is scant literature on autonomic symptoms in pediatric patients with hypermobile Ehlers-Danlos syndrome. This study aims to characterize cardiovascular symptoms and diagnoses in pediatric patients with hypermobile Ehlers-Danlos syndrome and evaluate the impact of autonomic symptoms on quality of life.

Methods

As part of a longitudinal study, a consecutive sample of 70 patients with Ehlers-Danlos syndromes were recruited at routine clinical care visits. Medical history was reviewed, demographics were obtained, and patient-reported outcomes were completed by the patients.

Results

The average age of 70 patients was 15.8 years, and the majority were females (89%) and Caucasian (89%). The most common cardiovascular diagnoses were orthostatic intolerance (59%), dysautonomia (47%), and postural orthostatic tachycardia syndrome (21%). Most patients had an echocardiogram (77%), that was normal (82%). No patients had mitral valve prolapse, and only one patient had mild aortic root dilation (2%). Patient-reported outcomes revealed decreased quality of life associated with autonomic symptoms.

Conclusions

This study shows that most children with hypermobile Ehlers-Danlos syndrome have cardiovascular and autonomic symptoms, which have a negative impact on quality of life. Few patients with hypermobile Ehlers-Danlos syndrome have structural abnormalities on echocardiogram, which suggests that the cardiovascular symptoms experienced by patients are not due to structural cardiovascular disease and possibly reflective of autonomic pathology, though further studies will need to confirm this. This study confirms that cardiovascular and symptoms are prevalent and have a dramatic impact on quality of life in pediatric and young adult patients diagnosed with hypermobile Ehlers-Danlos syndrome.

Brazilian Guideline for Exercise Testing in Children and Adolescents - 2024

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Significance of Fibrillin-1, Filamin A, MMP2 and SOX9 in Mitral Valve Pathology

Genetic factors play a significant role in the pathogenesis of mitral valve diseases, including mitral valve prolapse (MVP) and mitral valve regurgitation. Genes like Fibrillin-1 (FBN1), Filamin A (FLNA), matrix metalloproteinase 2 (MMP2), and SRY-box transcription factor 9 (SOX9) are known to influence mitral valve pathology but knowledge of the exact mechanism is far from clear. Data regarding serum parameters, transesophageal echocardiography, and genetic and histopathologic parameters were investigated in 54 patients who underwent cardiovascular surgery for mitral valve regurgitation. The possible association between Fibrillin-1, Filamin A, MMP2, and SOX9 gene expressions was checked in relationship with the parameters of systemic inflammatory response. The mRNA expression levels (RQ-relative quantification) were categorized into three distinct groups: low (RQ < 1), medium/normal (RQ = 1-2), and high (RQ > 2). Severe fibrosis of the mitral valve was reflected by high expression of FBN1 and low expression of MMP2 (p < 0.05). The myxoid degeneration level was associated with the mRNA expression level for FBN1 and a low lymphocyte-monocyte ratio was associated with an increased mRNA expression of FBN1 (p < 0.05). A high number of monocytes was associated with high values of FBN1 whereas the increase in the number of lymphocytes was associated with high levels of MMP2. In addition, we observed that the risk of severe hyalinization was enhanced by a low mRNA expression of FLNA and/or SOX9. In conclusion, a lower FLNA mRNA expression can reflect the aging process that is highlighted in mitral valve pathology as a higher risk for hyalinization, especially in males, that might be prevented by upregulation of the SOX9 gene. FBN1 and MMP2 influence the inflammation-related fibrotic degeneration of the mitral valve. Understanding the genetic base of mitral valve pathology can provide insights into disease mechanisms, risk stratification, and potential therapeutic targets.

Unraveling the Mechanisms of Valvular Heart Disease to Identify Medical Therapy Targets: A Scientific Statement From the American Heart Association

Valvular heart disease is a common cause of morbidity and mortality worldwide and has no effective medical therapy. Severe disease is managed with valve replacement procedures, which entail high health care-related costs and postprocedural morbidity and mortality. Robust ongoing research programs have elucidated many important molecular pathways contributing to primary valvular heart disease. However, there remain several key challenges inherent in translating research on valvular heart disease to viable molecular targets that can progress through the clinical trials pathway and effectively prevent or modify the course of these common conditions. In this scientific statement, we review the basic cellular structures of the human heart valves and discuss how these structures change in primary valvular heart disease. We focus on the most common primary valvular heart diseases, including calcific aortic stenosis, bicuspid aortic valves, mitral valve prolapse, and rheumatic heart disease, and outline the fundamental molecular discoveries contributing to each. We further outline potential therapeutic molecular targets for primary valvular heart disease and discuss key knowledge gaps that might serve as future research priorities.

Echocardiographic assessment of left ventricular mechanics in individuals with mitral valve prolapse: a systematic review and meta-analysis

PURPOSE

During the last decade, a number of echocardiographic studies have employed speckle tracking echocardiography (STE) for assessing myocardial deformation properties in individuals with mitral valve prolapse (MVP), reporting not univocal results. Accordingly, we performed a systematic review and meta-analysis to summarize the main findings of these studies and to examine the overall influence of MVP on left ventricular (LV) global longitudinal strain (GLS).

METHODS

All echocardiographic studies assessing conventional echoDoppler parameters and myocardial strain indices in MVP individuals vs. controls without MVP, selected from PubMed and EMBASE databases, were included. The risk of bias was assessed by using the National Institutes of Health (NIH) Quality Assessment of Case-Control Studies. Continuous data (LV-GLS) were pooled as a standardized mean difference (SMD) comparing MVP group with healthy controls. The overall SMD of LV-GLS was calculated using the random-effect model.

RESULTS

The full-texts of 15 studies with 1088 individuals with MVP and 591 healthy controls were analyzed. Average LV-GLS magnitude was significantly, even though modestly, reduced in MVP individuals in comparison to controls (19.4 ± 3.4% vs. 21.1 ± 2.8%, P < 0.001). The overall effect of MVP on LV-GLS was small-to-medium (SMD - 0.54, 95%CI -0.76,-0.32, P < 0.001). Substantial heterogeneity was detected for the included studies, with an overall I2 statistic value of 75.9% (P < 0.001). Egger's test for a regression intercept gave a P-value of 0.58, indicating no publication bias. On meta-regression analysis, none of the moderators (the age, the percentage of females among MVP individuals, body mass index, heart rate and systolic blood pressure of MVP individuals, the degree of mitral regurgitation, the type of ultrasound machine employed for strain echocardiographic imaging and finally the beta blocker treatment) was significantly associated with effect modification (all P < 0.05). Regional strain analysis, performed by two-third of the studies, highlighted a more enhanced reduction in myocardial strain parameters at level of the LV basal infero-lateral segments in all directions (longitudinal, circumferential and radial), with apical sparing.

CONCLUSIONS

The longitudinal strain impairment detected in MVP individuals is more regional than global, with peculiar involvement of the LV basal infero-lateral segments and relative apical sparing pattern.

Cardiac magnetic resonance imaging in the evaluation and management of mitral valve prolapse - a comprehensive review

Mitral valve prolapse is a common valve disorder that usually has a benign prognosis unless there is significant regurgitation or LV impairment. However, a subset of patients are at an increased risk of ventricular arrhythmias and sudden cardiac death, which has led to the recognition of "arrhythmic mitral valve prolapse" as a clinical entity. Emerging risk factors include mitral annular disjunction and myocardial fibrosis. While echocardiography remains the primary method of evaluation, cardiac magnetic resonance has become crucial in managing this condition. Cine magnetic resonance sequences provide accurate characterization of prolapse and annular disjunction, assessment of ventricular volumes and function, identification of early dysfunction and remodeling, and quantitative assessment of mitral regurgitation when integrated with flow imaging. However, the unique strength of magnetic resonance lies in its ability to identify tissue changes. T1 mapping sequences identify diffuse fibrosis, in turn related to early ventricular dysfunction and remodeling. Late gadolinium enhancement sequences detect replacement fibrosis, an independent risk factor for ventricular arrhythmias and sudden cardiac death. There are consensus documents and reviews on the use of cardiac magnetic resonance specifically in arrhythmic mitral valve prolapse. However, in this article, we propose an algorithm for the broader use of cardiac magnetic resonance in managing this condition in various scenarios. Future advancements may involve implementing techniques for tissue characterization and flow analysis, such as 4D flow imaging, to identify patients with ventricular dysfunction and remodeling, increased arrhythmic risk, and more accurate grading of mitral regurgitation, ultimately benefiting patient selection for surgical therapy.

Arrhythmogenic Mitral Valve Prolapse: Can We Risk Stratify and Prevent Sudden Cardiac Death?

Ventricular arrhythmias associated with mitral valve prolapse (MVP) and the capacity to cause sudden cardiac death (SCD), referred to as 'malignant MVP', are an increasingly recognised, albeit rare, phenomenon. SCD can occur without significant mitral regurgitation, implying an interaction between mechanical derangements affecting the mitral valve apparatus and left ventricle. Risk stratification of these arrhythmias is an important clinical and public health issue to provide precise and targeted management. Evaluation requires patient and family history, physical examination and electrophysiological and imaging-based modalities. We provide a review of arrhythmogenic MVP, exploring its epidemiology, demographics, clinical presentation, mechanisms linking MVP to SCD, markers of disease severity, testing modalities and management, and discuss the importance of risk stratification. Even with recently improved understanding, it remains challenging how best to weight the prognostic importance of clinical, imaging and electrophysiological data to determine a clear high-risk arrhythmogenic profile in which an ICD should be used for the primary prevention of SCD.

Predictive nomogram for 28-day mortality risk in mitral valve disorder patients in the intensive care unit: A comprehensive assessment from the MIMIC-III database

BACKGROUND

Mitral valve disorder (MVD) stands as the most prevalent valvular heart disease. Presently, a comprehensive clinical index to predict mortality in MVD remains elusive. The aim of our study is to construct and assess a nomogram for predicting the 28-day mortality risk of MVD patients.

METHODS

Patients diagnosed with MVD were identified via ICD-9 code from the MIMIC-III database. Independent risk factors were identified utilizing the LASSO method and multivariate logistic regression to construct a nomogram model aimed at predicting the 28-day mortality risk. The nomogram's performance was assessed through various metrics including the area under the curve (AUC), calibration curves, Hosmer-Lemeshow test, integrated discriminant improvement (IDI), net reclassification improvement (NRI), and decision curve analysis (DCA).

RESULTS

The study encompassed a total of 2771 patients diagnosed with MVD. Logistic regression analysis identified several independent risk factors: age, anion gap, creatinine, glucose, blood urea nitrogen level (BUN), urine output, systolic blood pressure (SBP), respiratory rate, saturation of peripheral oxygen (SpO2), Glasgow Coma Scale score (GCS), and metastatic cancer. These factors were found to independently influence the 28-day mortality risk among patients with MVD. The calibration curve demonstrated adequate calibration of the nomogram. Furthermore, the nomogram exhibited favorable discrimination in both the training and validation cohorts. The calculations of IDI, NRI, and DCA analyses demonstrate that the nomogram model provides a greater net benefit compared to the Simplified Acute Physiology Score II (SAPSII), Acute Physiology Score III (APSIII), and Sequential Organ Failure Assessment (SOFA) scoring systems.

CONCLUSION

This study successfully identified independent risk factors for 28-day mortality in patients with MVD. Additionally, a nomogram model was developed to predict mortality, offering potential assistance in enhancing the prognosis for MVD patients. It's helpful in persuading patients to receive early interventional catheterization treatment, for example, transcatheter mitral valve replacement (TMVR), transcatheter mitral valve implantation (TMVI).

Imaging for the assessment of the arrhythmogenic potential of mitral valve prolapse

Mitral valve prolapse (MVP) is the most common valve disease in the western world and recently emerged as a possible substrate for sudden cardiac death (SCD). It is estimated an annual risk of sudden cardiac death of 0.2 to 1.9% mostly caused by complex ventricular arrhythmias (VA). Several mechanisms have been recognized as potentially responsible for arrhythmia onset in MVP, resulting from the combination of morpho-functional abnormality of the mitral valve, structural substrates (regional myocardial hypertrophy, fibrosis, Purkinje fibers activity, inflammation), and mechanical stretch. Echocardiography plays a central role in MVP diagnosis and assessment of severity of regurgitation. Several abnormalities detectable by echocardiography can be prognostic for the occurrence of VA, from morphological alteration including leaflet redundancy and thickness, mitral annular dilatation, and mitral annulus disjunction (MAD), to motion abnormalities detectable with "Pickelhaube" sign. Additionally, speckle-tracking echocardiography may identify MVP patients at higher risk for VA by detection of increased mechanical dispersion. On the other hand, cardiac magnetic resonance (CMR) has the capability to provide a comprehensive risk stratification combining the identification of morphological and motion alteration with the detection of myocardial replacement and interstitial fibrosis, making CMR an ideal method for arrhythmia risk stratification in patients with MVP. Finally, recent studies have suggested a potential role in risk stratification of new techniques such as hybrid PET-MR and late contrast enhancement CT. The purpose of this review is to provide an overview of the mitral valve prolapse syndrome with a focus on the role of imaging in arrhythmic risk stratification. CLINICAL RELEVANCE STATEMENT: Mitral valve prolapse is the most frequent valve condition potentially associated with arrhythmias. Imaging has a central role in the identification of anatomical, functional, mechanical, and structural alterations potentially associated with a higher risk of developing complex ventricular arrhythmia and sudden cardiac death. KEY POINTS: • Mitral valve prolapse is a common valve disease potentially associated with complex ventricular arrhythmia and sudden cardiac death. • The mechanism of arrhythmogenesis in mitral valve prolapse is complex and multifactorial, due to the interplay among multiple conditions including valve morphological alteration, mechanical stretch, myocardial structure remodeling with fibrosis, and inflammation. • Cardiac imaging, especially echocardiography and cardiac magnetic resonance, is crucial in the identification of several features associated with the potential risk of serious cardiac events. In particular, cardiac magnetic resonance has the advantage of being able to detect myocardial fibrosis which is currently the strongest prognosticator.

When annuloplasty is not enough: a case report of ventricular arrhythmias stepwise abolition after mitral valve re-repair

Background

Some patients affected by mitral valve (MV) prolapse (MVP) are at higher risk of ventricular arrhythmias (VAs), but the underlying pathogenesis, as well as the effects of surgery on VA, remain not fully understood. Mitral valve repair, however, represents a privileged point of view to deepen the understanding of arrhythmogenesis in this context. Hence, we report an interesting case of MV re-repair.

Case summary

A 52-year-old man was referred to our institution for severe mitral regurgitation (MR) due to P2 prolapse in the context of myxomatous MV degeneration. Pre-operative imaging showed systolic mitral annular disjunction, left ventricular (LV) wall curling, Pickelhaube's sign, and a prolapsing tricuspid valve (TV) with only mild regurgitation. Twenty-four-hour electrocardiogram (ECG) Holter revealed a significant burden of premature ventricular contractions (PVCs), most of them originating from anterior papillary muscle (APM), posterior papillary muscle (PPM), and mitral annulus (MA). Quadrangular resection of P2 and mitral annuloplasty were performed. One year later, relapse of severe MR due to a residual P2M1 prolapse occurred. Twenty-four-hour ECG Holter showed no PVCs from PPM and MA, while those from APM persisted. A central edge-to-edge repair was effectively used to fix the residual prolapse. After 1 year from REDO surgery, a third ECG Holter confirmed the absence of any remaining LV PVCs, but still few ectopic beats originating from TV were recorded.

Discussion

Here, we report a case of VA resolution after specific, anatomical triggers addressing surgical gestures. Our experience confirms that MV surgery may have a role in MVP patients' arrhythmias correction.

2023 Korean Society of Echocardiography position paper for the diagnosis and management of valvular heart disease, part II: mitral and tricuspid valve disease

This manuscript represents the official position of the Korean Society of Echocardiography on valvular heart diseases. This position paper focuses on the diagnosis and management of valvular heart diseases with referring to the guidelines recently published by the American College of Cardiology/American Heart Association and the European Society of Cardiology. The committee sought to reflect national data on the topic of valvular heart diseases published to date through a systematic literature search based on validity and relevance. In the part II of this article, we intend to present recommendations for diagnosis and treatment of mitral valve disease and tricuspid valve disease.

Phenotypic Clusters and Multimorbidity in Hypermobile Ehlers-Danlos Syndrome

Objective

To perform a retrospective clinical study in order to investigate phenotypic penetrance within a large registry of patients with hypermobile Ehlers-Danlos syndrome (hEDS) to enhance diagnostic and treatment guidelines by understanding associated comorbidities and improving accuracy in diagnosis.

Patients and Methods

From May 1, 2021 to July 31, 2023, 2149 clinically diagnosed patients with hEDS completed a self-reported survey focusing on diagnostic and comorbid conditions prevalence. K-means clustering was applied to analyze survey responses, which were then compared across gender groups to identify variations and gain clinical insights.

Results

Analysis of clinical manifestations in this cross-sectional cohort revealed insights into multimorbidity patterns across organ systems, identifying 3 distinct patient groups. Differences among these phenotypic clusters provided insights into diversity within the population with hEDS and indicated that Beighton scores are unreliable for multimorbidity phenotyping.

Conclusion

Clinical data on the phenotypic presentation and prevalence of comorbidities in patients with hEDS have historically been limited. This study provides comprehensive data sets on phenotypic presentation and comorbidity prevalence in patients with hEDS, highlighting factors often overlooked in diagnosis. The identification of distinct patient groups emphasizes variations in hEDS manifestations beyond current guidelines and emphasizes the necessity of comprehensive multidisciplinary care for those with hEDS.

Primary Atriopathy in Mitral Valve Prolapse: Echocardiographic Evidence and Clinical Implications

BACKGROUND

Prominent multi-scallop systolic leaflet displacement toward the left atrium (atrialization) is typically observed in bileaflet mitral valve prolapse (MVP) with mitral annular disjunction. We hypothesized that mitral leaflet atrialization is associated with an underlying left atrial (LA) myopathy characterized by progressive structural and functional abnormalities, irrespective of mitral regurgitation (MR) severity.

METHODS

We identified 334 consecutive patients with MVP, no prior atrial fibrillation, and comprehensive clinical and echocardiographic data. LA function was assessed by LA reservoir strain, LA function index, and LA emptying fraction. We also classified the stage of LA remodeling based on LA enlargement and LA reservoir strain (stage 1: no remodeling; stage 2: mild remodeling; stage 3: moderate remodeling; and stage 4: severe remodeling). The primary end point was the composite risk of sudden arrhythmic death, heart failure hospitalization, or the new onset of atrial fibrillation.

RESULTS

Bileaflet MVP with no or mild MR had a lower LA reservoir strain (P=0.04) and LA function index (P<0.001) compared with other MVP subtypes. In multivariable linear regression adjusted for cardiovascular risk factors and MR ≥moderate, bileaflet MVP remained significantly associated with lower LA function parameters (all P<0.05). There was a significant increase in the risk of events as the LA reservoir strain and LA remodeling stage increased (P<0.001). In multivariable analysis, stage 4 of LA remodeling remained significantly associated with a higher risk of events compared with stage 1 (hazard ratio, 6.09 [95% CI, 1.69-21.9]; P=0.006).

CONCLUSIONS

In a large MVP registry, bileaflet involvement is associated with reduced LA function regardless of MR severity, suggesting a primary atriopathy in this MVP subtype. Abnormal LA function, particularly when assessed through a multiparametric approach, is linked to a higher risk of cardiovascular events and may improve risk stratification in MVP, even in those without significant MR.

Biobehavioral approach to distinguishing panic symptoms from medical illness

Panic disorder is a common psychiatric diagnosis characterized by acute, distressing somatic symptoms that mimic medically-relevant symptoms. As a result, individuals with panic disorder overutilize personal and healthcare resources in an attempt to diagnose and treat physical symptoms that are often medically benign. A biobehavioral perspective on these symptoms is needed that integrates psychological and medical knowledge to avoid costly treatments and prolonged suffering. This narrative review examines six common somatic symptoms of panic attacks (non-cardiac chest pain, palpitations, dyspnea, dizziness, abdominal distress, and paresthesia), identified in the literature as the most severe, prevalent, or critical for differential diagnosis in somatic illness, including long COVID. We review somatic illnesses that are commonly comorbid or produce panic-like symptoms, their relevant risk factors, characteristics that assist in distinguishing them from panic, and treatment approaches that are typical for these conditions. Additionally, this review discusses key factors, including cultural considerations, to assist healthcare professionals in differentiating benign from medically relevant symptoms in panic sufferers.

What Do We Know So Far About Ventricular Arrhythmias and Sudden Cardiac Death Prediction in the Mitral Valve Prolapse Population? Could Biomarkers Help Us Predict Their Occurrence?

PURPOSE OF THE REVIEW

To summarize currently available data on the topic of mitral valve prolapse (MVP) and its correlation to the occurrence of atrial and ventricular arrhythmias. To assess the prognostic value of several diagnostic methods such as transthoracic echocardiography, transesophageal echocardiography, cardiac magnetic resonance, cardiac computed tomography, electrocardiography, and electrophysiology concerning arrhythmic episodes. To explore intra and extracellular biochemistry of the cardiovascular system and its biomarkers as diagnostic tools to predict rhythm disturbances in the MVP population.

RECENT FINDINGS

MVP is a common and mainly benign valvular disorder. It affects 2-3% of the general population. MVP is a heterogeneous and highly variable phenomenon with three structural phenotypes: myxomatous degeneration, fibroelastic deficiency, and forme fruste. Exercise intolerance, supraventricular tachycardia, and chest discomfort are the symptoms that are often paired with psychosomatic components. Though MVP is thought to be benign, the association between isolated MVP without mitral regurgitation (MR) or left ventricle dysfunction, with ventricular arrhythmia (VA) and sudden cardiac death (SCD) has been observed. The incidence of SCD in the MVP population is around 0.6% per year, which is 6 times higher than the occurrence of SCD in the general population. Often asymptomatic MVP population poses a challenge to screen for VA and prevent SCD. Therefore, it is crucial to carefully assess the risk of VA and SCD in patients with MVP with the use of various tools such as diagnostic imaging and biochemical and genetic screening.

Determinants of Ventricular Arrhythmias in Mitral Valve Prolapse

BACKGROUND

Mitral valve prolapse (MVP) may be associated with ventricular arrhythmias (VA) even in the absence of significant valvular regurgitation. Curling, mitral annulus disjunction (MAD) and myocardial fibrosis (late gadolinium enhancement [LGE]) may account for arrhythmogenesis.

OBJECTIVES

This study investigated the determinants of VA in patients with MVP without significant regurgitation.

METHODS

This study included 108 patients with MVP (66 female; median age: 48 years) without valve regurgitation. All patients underwent 12-lead electrocardiography, 12-lead 24-hour electrocardiographic Holter monitoring, exercise stress test, and cardiac magnetic resonance. Patients were divided into 2 groups (arrhythmic and no-arrhythmic MVP), according to the presence of VA with a right bundle branch block pattern.

RESULTS

The 62 patients (57%) with arrhythmic MVP showed: 1) higher MAD (median length: 6.0 vs 3.2 mm; P = 0.017); 2) higher prevalence of curling (79% vs 52%; P = 0.012); and 3) higher prevalence of left ventricular LGE (79% vs 52%; P = 0.012). Mediation analysis showed that curling had both a direct (P = 0.03) and indirect effect mediated by LGE (P = 0.04) on VA, whereas the association between MAD and VA was completely mediated by LGE. Patients with severe VA showed more pronounced morphofunctional alterations, in terms of MAD (7.0 vs 4.6 mm; P = 0.004) and presence and severity of curling (respectively, 91% vs 64%; P = 0.010; and 4 vs 3 mm; P = 0.004), compared to those without severe VA.

CONCLUSIONS

In patients with MVP the occurrence of VA with right bundle branch block morphology is the expression of more severe morphologic, mechanical, and tissue alterations. Curling has both a direct and an indirect effect on VA.

Minimally Invasive Mitral Valve Repair Using Transcatheter Chordal Attachments

The advent of transcatheter mitral chordal replacement techniques has offered an alternative approach that is less invasive and may be more suitable for select patients compared with surgical repair. These systems involve introducing artificial chordae, via catheter, to replace or supplement damaged or elongated natural chordae. These artificial chordae are anchored at one end to the mitral leaflet and the other end to the papillary muscle or directly to the left ventricular apex, restoring the leaflet's coaptation and reducing regurgitation. Early trials and studies suggest promising results in terms of safety and efficacy in reducing MR severity and improving symptoms.

The Value of the Electrocardiogram in Adult Congenital Heart Disease

The electrocardiogram is the first test that is undertaken when evaluating a patient's heart. Diagnosing congenital heart disease in an adult (ACHD) can be facilitated by knowing the classical electrocardiographic (EKG) findings. These EKG findings often result from the congenital defect that prevents a part of the cardiac conduction system from occupying its normal anatomic position. When these classical EKG findings are not present, the clinician should consider alternate diagnoses. As the patient with congenital heart disease ages, with native anatomy or after surgical or device repair, the EKG can be used to assess the patient's status and to decide if and when treatment requires adjustment. This is because the electrocardiogram (EKG) can diagnose the hypertrophy or enlargement in a cardiac chamber that results from the congenital defect or anomaly and can diagnose an arrhythmia that might compromise an otherwise stable anatomy. While ACHD often involves intracardiac shunting, in many cases the abnormality only involves cardiac electrical conduction block or ventricular repolarization. These life-threatening diseases can be diagnosed with an EKG. This review will demonstrate and explain how the EKG can be used to diagnose and follow adults with congenital heart disease. When coupled with history and physical examination, the value of the EKG in ACHD will be apparent. A diagnosis can then be made or a differential diagnosis proposed, before an imaging study is ordered.

Left ventricular fibrosis in arrhythmic mitral valve prolapse: quantification and comparison of semi-automated techniques assessed by cardiac magnetic resonance

PURPOSE

Left ventricular (LV) fibrosis has a key role in arrhythmogenesis in patients with mitral valve prolapse (MVP). Cardiac magnetic resonance identifies LV fibrosis by using late gadolinium enhancement (LGE) technique. LGE assessment and quantification in patients with MVP lacks of standardization protocols.

METHODS

66 MVP patients with normal systolic function and without significant regurgitation were enrolled. Semi-automated gray-scale thresholding techniques using full width at half maximum (FWHM) and 2, 3 and 5 standard deviation (SD) above the remote myocardium were used and compared with the visual assessment, considered as the gold standard.

RESULTS

LGE was identified in 41 MVP patients (62%) and quantified. The mean quantity of LGE visually assessed was 2.40 ± 1.07% or 1.40 ± 0.82 g. With FWHM, LGE resulted 3.56 ± 1.23% or 1.99 ± 1.13 g. Using thresholding, the mean LGE quantity was 9.2 ± 3.1% or 4.82 ± 2.28 g for 2-SD, 5.72 ± 1.75% or 3.06 ± 1.47 g for 3-SD and 2.36 ± 0.99% or 1.29 ± 0.79 g for 5-SD. The 5-SD measurement in percentage demonstrated a good correlation with LGE quantification visually assessed (2.40 ± 1.07 vs. 2.363 ± 0.9909, p = 0.543). When compared with the gold standard, the 5-SD threshold quantification, both in percentage and in grams, revealed the least intra-observer (respectively, ICC: 0.976 and 0.966) and inter-observer variability (respectively ICC: 0.948 and 0.935).

CONCLUSION

The 5-SD gray-scale threshold technique in percentage revealed the best correlation with the visual assessment and an optimal reproducibility in MVP patient.

Arrhythmic risk profile in mitral valve prolapse: A systematic review and metanalysis of 1715 patients

INTRODUCTION

Mitral valve prolapse (MVP) is a common clinical condition in the general population. A subgroup of patients with MVP may experience ventricular arrhythmias and sudden cardiac death ("arrhythmic mitral valve prolapse" [AMVP]) but how to stratify arrhythmic risk is still unclear. Our meta-analysis aims to identify predictive factors for arrhythmic risk in patients with MVP.

METHODS

We systematically searched Medline, Cochrane, Journals@Ovid, Scopus electronic databases for studies published up to December 28, 2022 and comparing AMVP and nonarrhythmic mitral valve prolapse (NAMVP) for what concerns history, electrocardiographic, echocardiographic and cardiac magnetic resonance features. The effect size was estimated using a random-effect model as odds ratio (OR) and mean difference (MD).

RESULTS

A total of 10 studies enrolling 1715 patients were included. Late gadolinium enhancement (LGE) (OR: 16.67; p = .005), T-wave inversion (TWI) (OR: 2.63; p < .0001), bileaflet MVP (OR: 1.92; p < .0001) and mitral anulus disjunction (MAD) (OR: 2.60; p < .0001) were more represented among patients with AMVP than in NAMVP. Patients with AMVP were shown to have longer anterior mitral leaflet (AML) (MD: 2.63 mm; p < .0001), posterior mitral leaflet (MD: 2.96 mm; p < .0001), thicker AML (MD: 0.49 mm; p < .0001), longer MAD length (MD: 1.24 mm; p < .0001) and higher amount of LGE (MD: 1.41%; p < .0001) than NAMVP. AMVP showed increased mechanical dispersion (MD: 8.04 ms; 95% confidence interval: 5.13-10.96; p < .0001) compared with NAMVP.

CONCLUSIONS

Our meta-analysis proved that LGE, TWI, bileaflet MVP, and MAD are predictive factors for arrhythmic risk in MVP patients.

Feasibility Study of a Novel Transapical Chordal Implantation System in a Porcine Model

Transapical beating-heart mitral repair with chordal implantation system has been considered as an alternative treatment for degenerative mitral regurgitation. This study aimed to assess the feasibility and safety of the E-Chord system (Med-Zenith Medical, Beijing, China) for transapical beating-heart mitral valve repair in a porcine model. Artificial chordae were transapically implanted on the mitral valves of 12 anesthetized pigs under epicardial echocardiographic guidance and secured outside the left ventricular apex. The study endpoints included procedural success, device durability, and tissue response to the device. The procedural success rate was 100% (12/12). All animals were implanted with E-Chord in the anterior and posterior leaflets, respectively, and survived uneventfully until euthanized as planned. During the 180-day follow-up, no animal had significant mitral valve dysfunction. The gross observation showed no evidence of anchor detachment and chordal rupture, and there was no obvious damage or changes to mitral leaflets. Microscopic evaluation revealed that the endothelialization of anchor and chordae was completed 90 days after implantation and there was no evidence of chordal rupture, thrombosis, or infection during the 180-day follow-up. The E-Chord system was found to be feasible and safe for heart-beating mitral chordal implantation in a porcine model. The findings of this study suggest that the E-Chord system may be a potential alternative for the treatment of degenerative mitral regurgitation in humans.

The Potential of Intertwining Gene Diagnostics and Surgery for Mitral Valve Prolapse

Mitral valve prolapse (MVP) is common among heart valve disease patients, causing severe mitral regurgitation (MR). Although complications such as cardiac arrhythmias and sudden cardiac death are rare, the high prevalence of the condition leads to a significant number of such events. Through next-generation gene sequencing approaches, predisposing genetic components have been shown to play a crucial role in the development of MVP. After the discovery of the X-linked inheritance of filamin A, autosomal inherited genes were identified. In addition, the study of sporadic MVP identified several genes, including DZIP1, TNS1, LMCD1, GLIS1, PTPRJ, FLYWCH, and MMP2. The early screening of these genetic predispositions may help to determine the patient population at risk for severe complications of MVP and impact the timing of reconstructive surgery. Surgical mitral valve repair is an effective treatment option for MVP, resulting in excellent short- and long-term outcomes. Repair rates in excess of 95% and low complication rates have been consistently reported for minimally invasive mitral valve repair performed in high-volume centers. We therefore conceptualize a potential preventive surgical strategy for the treatment of MVP in patients with genetic predisposition, which is currently not considered in guideline recommendations. Further genetic studies on MVP pathology and large prospective clinical trials will be required to support such an approach.

High-risk phenotypes of arrhythmic mitral valve prolapse: a systematic review and meta-analysis

BACKGROUND

Mitral valve prolapse (MVP) is associated with aggravated risk of ventricular tachycardia (VT), ventricular fibrillation (VF) and sudden cardiac death (SCD). There is a lack of specific guideline recommendation regarding risk stratification and management, despite multiple proposed high-risk phenotypes. We performed systematic review and meta-analysis to evaluate high-risk phenotypes for malignant arrhythmias in patients with MVP.

METHODS

We comprehensively searched the databases of MEDLINE, SCOPUS, and EMBASE from inception to April 2023. Included studies were cohort and case-control comparing between MVP patients with and without VT, VF, cardiac arrest, ICD placement, or SCD. Data from each study were combined using the random-effects. Pooled odds ratios (OR) and 95% confidence intervals (CI) were calculated.

RESULTS

Nine studies from 1985 to 2023 were included involving 2,279 patients with MVP. We found that T-wave inversion (OR 2.52; 95% CI: 1.90-3.33; p < 0.001), bileaflet involvement (OR 2.28; 95% CI: 1.69-3.09; p < 0.001), late gadolinium enhancement (OR 17.05; 95% CI: 3.41-85.22; p < 0.001), mitral annular disjunction (OR 3.71; 95% CI: 1.63-8.41; p < 0.002), and history of syncope (OR 6.96; 95% CI: 1.05-46.01; p = 0.044), but not female (OR 0.96; 95% CI: 0.46-2.01; p = 0.911), redundant leaflets (OR 4.30; 95% CI: 0.81-22.84; p = 0.087), or moderate-to-severe mitral regurgitation (OR 1.24; 95% CI: 0.65-2.37; p = 0.505), were associated with those events.

CONCLUSION

Bileaflet prolapse, T-wave inversion, mitral annular disjunction, late gadolinium enhancement, and history of syncope are high-risk phenotypes among population with MVP. Further research is needed to validate the risk stratification model and justify the role of primary prophylaxis against malignant arrhythmias.

Ecosystem health and malfunctions: an organisational perspective

A recent idea of "ecosystem health" was introduced in the 1970s and 1980s to draws attention to the fact that ecosystems can become ill because of a reduction of properties such as primary productivity, functions and diversity of interactions among system components. Starting from the 1990s, this idea has been deeply criticized by authors who argued that, insofar as ecosystems show many differences with respect to organismic features, these two kinds of systems cannot share a typical organismic property such as health. In recent years, an organisational approach in philosophy of biology and ecology argued that both organisms and ecosystems may share a fundamental characteristic despite their differences, namely, organisational closure. Based on this kind of closure, scholars have also discussed health and malfunctional states in organisms. In this paper, we examine the possibility of expanding such an organisational approach to health and malfunctions to the ecological domain. Firstly, we will see that a malfunction is related to a lower effectiveness in the functional behaviour of some biotic components with respect to other systemic components. We will then show how some introduced species do not satisfactorily interact in an organisational closure with other ecosystem components, thus posing a threat to the self-maintenance of the ecosystem in which they are found. Accordingly, we will argue that an ecosystem can be said to be healthy when it is a vital environment organisationally grounded on its intrinsic capacity to ensure, under favourable conditions, appropriate functional behaviours for ecosystem components and ecosystem self-maintenance.

Arrhythmic Mitral Valve Prolapse: A Comprehensive Review

Mitral valve prolapse (MVP) is a prevalent cardiac disorder that impacts approximately 2% to 3% of the overall population. While most patients experience a benign clinical course, there is evidence suggesting that a subgroup of MVP patients face an increased risk of sudden cardiac death (SCD). Although a conclusive causal link between MVP and SCD remains to be firmly established, various factors have been associated with arrhythmic mitral valve prolapse (AMVP). This study aims to provide a comprehensive review encompassing the historical background, epidemiology, pathology, clinical manifestations, electrocardiogram (ECG) findings, and treatment of AMVP patients. A key focus is on utilizing multimodal imaging techniques to accurately diagnose AMVP and to highlight the role of mitral annular disjunction (MAD) in AMVP.

PROX1 Inhibits PDGF-B Expression to Prevent Myxomatous Degeneration of Heart Valves

BACKGROUND

Cardiac valve disease is observed in 2.5% of the general population and 10% of the elderly people. Effective pharmacological treatments are currently not available, and patients with severe cardiac valve disease require surgery. PROX1 (prospero-related homeobox transcription factor 1) and FOXC2 (Forkhead box C2 transcription factor) are transcription factors that are required for the development of lymphatic and venous valves. We found that PROX1 and FOXC2 are expressed in a subset of valvular endothelial cells (VECs) that are located on the downstream (fibrosa) side of cardiac valves. Whether PROX1 and FOXC2 regulate cardiac valve development and disease is not known.

METHODS

We used histology, electron microscopy, and echocardiography to investigate the structure and functioning of heart valves from Prox1ΔVEC mice in which Prox1 was conditionally deleted from VECs. Isolated valve endothelial cells and valve interstitial cells were used to identify the molecular mechanisms in vitro, which were tested in vivo by RNAScope, additional mouse models, and pharmacological approaches. The significance of our findings was tested by evaluation of human samples of mitral valve prolapse and aortic valve insufficiency.

RESULTS

Histological analysis revealed that the aortic and mitral valves of Prox1ΔVEC mice become progressively thick and myxomatous. Echocardiography revealed that the aortic valves of Prox1ΔVEC mice are stenotic. FOXC2 was downregulated and PDGF-B (platelet-derived growth factor-B) was upregulated in the VECs of Prox1ΔVEC mice. Conditional knockdown of FOXC2 and conditional overexpression of PDGF-B in VECs recapitulated the phenotype of Prox1ΔVEC mice. PDGF-B was also increased in mice lacking FOXC2 and in human mitral valve prolapse and insufficient aortic valve samples. Pharmacological inhibition of PDGF-B signaling with imatinib partially ameliorated the valve defects of Prox1ΔVEC mice.

CONCLUSIONS

PROX1 antagonizes PDGF-B signaling partially via FOXC2 to maintain the extracellular matrix composition and prevent myxomatous degeneration of cardiac valves.

Identifying Mitral Valve Prolapse at Risk for Arrhythmias and Fibrosis From Electrocardiograms Using Deep Learning

BACKGROUND

Mitral valve prolapse (MVP) is a common valvulopathy, with a subset developing sudden cardiac death or cardiac arrest. Complex ventricular ectopy (ComVE) is a marker of arrhythmic risk associated with myocardial fibrosis and increased mortality in MVP.

OBJECTIVES

The authors sought to evaluate whether electrocardiogram (ECG)-based machine learning can identify MVP at risk for ComVE, death and/or myocardial fibrosis on cardiac magnetic resonance (CMR) imaging.

METHODS

A deep convolutional neural network (CNN) was trained to detect ComVE using 6,916 12-lead ECGs from 569 MVP patients from the University of California-San Francisco between 2012 and 2020. A separate CNN was trained to detect late gadolinium enhancement (LGE) using 1,369 ECGs from 87 MVP patients with contrast CMR.

RESULTS

The prevalence of ComVE was 28% (160/569). The area under the receiver operating characteristic curve (AUC) of the CNN to detect ComVE was 0.80 (95% CI: 0.77-0.83) and remained high after excluding patients with moderate-severe mitral regurgitation [0.80 (95% CI: 0.77-0.83)] or bileaflet MVP [0.81 (95% CI: 0.76-0.85)]. AUC to detect all-cause mortality was 0.82 (95% CI: 0.77-0.87). ECG segments relevant to ComVE prediction were related to ventricular depolarization/repolarization (early-mid ST-segment and QRS from V1, V3, and III). LGE in the papillary muscles or basal inferolateral wall was present in 24% patients with available CMR; AUC for detection of LGE was 0.75 (95% CI: 0.68-0.82).

CONCLUSIONS

CNN-analyzed 12-lead ECGs can detect MVP at risk for ventricular arrhythmias, death and/or fibrosis and can identify novel ECG correlates of arrhythmic risk. ECG-based CNNs may help select those MVP patients requiring closer follow-up and/or a CMR.

Biology of mitral valve prolapse: from general mechanisms to advanced molecular patterns-a narrative review

Mitral valve prolapse (MVP) represents the most frequent cause of primary mitral regurgitation. For several years, biological mechanisms underlying this condition attracted the attention of investigators, trying to identify the pathways responsible for such a peculiar condition. In the last ten years, cardiovascular research has moved from general biological mechanisms to altered molecular pathways activation. Overexpression of TGF-β signaling, for instance, was shown to play a key role in MVP, while angiotensin-II receptor blockade was found to limit MVP progression by acting on the same signaling pathway. Concerning extracellular matrix organization, the increased valvular interstitial cells density and dysregulated production of catalytic enzymes (matrix metalloproteinases above all) altering the homeostasis between collagen, elastin and proteoglycan components, have been shown to possibly provide a mechanistic basis contributing to the myxomatous MVP phenotype. Moreover, it has been observed that high levels of osteoprotegerin may contribute to the pathogenesis of MVP by increasing collagen deposition in degenerated mitral leaflets. Although MVP is believed to represent the result of multiple genetic pathways alterations, it is important to distinguish between syndromic and non-syndromic conditions. In the first case, such as in Marfan syndrome, the role of specific genes has been clearly identified, while in the latter a progressively increasing number of genetic loci have been thoroughly investigated. Moreover, genomics is gaining more interest as potential disease-causing genes and loci possibly associated with MVP progression and severity have been identified. Animal models could be of help in better understanding the molecular basis of MVP, possibly providing sufficient information to tackle specific mechanisms aimed at slowing down MVP progression, therefore developing non-surgical therapies impacting on the natural history of this condition. Although continuous progress has been made in this field, further translational studies are advocated to improve our knowledge of biological mechanisms underlying MVP development and progression.

Mitral valve prolapse and physical performance in Asian military males: The CHIEF Heart study

The impact of mitral valve prolapse (MVP) and mitral regurgitation (MR) on physical performance has not been examined. Of 1,808 physically fit Asian military males, we compared the physical fitness between 62 subjects with MVP (MVP(+)) and 1,311 age- and anthropometrics-matched controls from the 1,746 participants without MVP (MVP(-)). MVP and MR grade were defined based on the American Society of Echocardiography criteria. Aerobic endurance capacity was evaluated by a 3000-m run and muscular endurance capacity was separately evaluated by 2-min sit-ups and 2-min push-ups. Analysis of covariance was used to determine the difference between groups. As compared to the MVP(-), the MVP(+) completed the 3000-m run test faster (839.2 ± 65.3 sec vs. 866.6 ± 86.8 sec, p = 0.019), but did fewer push-ups (41.3 ± 3.92 vs. 48.0 ± 10.1, p = 0.02) and similar sit-ups within 2 min. Of the MVP(+), those with any MR (trivial, mild or moderate) completed the 3000-m run test faster than those without MR (830.6 ± 61.7 sec vs. 877.2 ± 61.7 sec, p = 0.02). Our findings suggest that in physically active Asian military males, the MVP(+) may have greater aerobic endurance capacity but lower muscular endurance capacity than the MVP(-). The presence of MR may play a role for the MVP(+) to have greater aerobic endurance capacity.

Sex Differences in Epidemiology, Morphology, Mechanisms, and Treatment of Mitral Valve Regurgitation

Sex-related disparities have been recognized in incidence, pathological findings, pathophysiological mechanisms, and diagnostic pathways of non-rheumatic mitral regurgitation. Furthermore, access to treatments and outcomes for surgical and interventional therapies among women and men appears to be different. Despite this, current European and US guidelines have identified common diagnostic and therapeutic pathways that do not consider patient sex in decision-making. The aim of this review is to summarize the current evidence on sex-related differences in non-rheumatic mitral regurgitation, particularly regarding incidence, imaging modalities, surgical-derived evidence, and outcomes of transcatheter edge-to-edge repair, with the goal of informing clinicians about sex-specific challenges to consider when making treatment decisions for patients with mitral regurgitation.

Mitral and Tricuspid Valve Disease in Athletes

Observing mitral or tricuspid valve disease in an athlete raises many considerations for the clinician. Initially, the etiology must be clarified, with causes differing depending on whether the athlete is young or a master. Notably, vigorous training in competitive athletes leads to a constellation of structural and functional adaptations involving cardiac chambers and atrioventricular valve systems. In addition, a proper evaluation of the athlete with valve disease is necessary to evaluate the eligibility for competitive sports and identify those requiring more follow-up. Indeed, some valve pathologies are associated with an increased risk of severe arrhythmias and potentially sudden cardiac death. Traditional and advanced imaging modalities help clarify clinical doubts, allowing essential information about the athlete's physiology and differentiating between primary valve diseases from those secondary to training-related cardiac adaptations. Remarkably, another application of multimodality imaging is evaluating athletes with valve diseases during exercise to reproduce the sport setting and better characterize the etiology and valve defect mechanism. This review aims to analyze the possible causes of atrioventricular valve diseases in athletes, focusing primarily on imaging applications in diagnosis and risk stratification.

Comparison of Cardiorespiratory Fitness between Patients with Mitral Valve Prolapse and Healthy Peers: Findings from Serial Cardiopulmonary Exercise Testing

Individuals with mitral valve prolapse (MVP) have exercise intolerance even without mitral valve regurgitation. Mitral valve degeneration may progress with aging. We aimed to evaluate the influence of MVP on the cardiopulmonary function (CPF) of individuals with MVP through serial follow-ups from early to late adolescence. Thirty patients with MVP receiving at least two cardiopulmonary exercise tests (CPETs) using a treadmill (MVP group) were retrospectively analyzed. Age-, sex-, and body mass index-matched healthy peers, who also had serial CPETs, were recruited as the control group. The average time from the first CPET to the last CPET was 4.28 and 4.06 years in the MVP and control groups, respectively. At the first CPET, the MVP group had a significantly lower peak rate pressure product (PRPP) than the control group (p = 0.022). At the final CEPT, the MVP group had lower peak metabolic equivalent (MET, p = 0.032) and PRPP (p = 0.031). Moreover, the MVP group had lower peak MET and PRPP as they aged, whereas healthy peers had higher peak MET (p = 0.034) and PRPP (p = 0.047) as they aged. Individuals with MVP had poorer CPF than healthy individuals as they develop from early to late adolescence. It is important for individuals with MVP to receive regular CPET follow-ups.

The MIDA-Q Mortality Risk Score: A Quantitative Prognostic Tool for the Mitral Valve Prolapse Spectrum

BACKGROUND

Mitral valve prolapse (MVP) is responsible for a considerable disease burden but is widely heterogeneous. The lack of a comprehensive prognostic instrument covering the entire MVP spectrum, encompassing the quantified consequent degenerative mitral regurgitation (DMR), hinders clinical management and therapeutic trials.

METHODS

The new Mitral Regurgitation International Database Quantitative (MIDA-Q) registry enrolled 8187 consecutive patients (ages 63±16 years, 47% women, follow-up 5.5±3.3 years) first diagnosed with isolated MVP, without or with DMR quantified prospectively (measuring effective regurgitant orifice [ERO] and regurgitant volume) in routine practice of 5 tertiary care centers from North America, Europe, and the Middle East. The MIDA-Q score ranges from 0 to 15 by accumulating guideline-based risk factors and DMR severity. Long-term survival under medical management was the primary outcome end point.

RESULTS

MVP was associated with DMR absent/mild (ERO <20 mm2) in 50%, moderate (ERO 20-40 mm2) in 25%, and severe or higher (ERO ≥40 mm2) in 25%, with mean ERO 24±24 mm2, regurgitant volume 37±35 mL. Median MIDA-Q score was 4 with a wide distribution (10%-90% range, 0-9). MIDA-Q score was higher in patients with EuroScore II ≥1% versus <1% (median, 7 versus 3; P < 0.0001) but with wide overlap (10%-90% range, 4-11 versus 0-7) and mediocre correlation (R2 0.18). Five-year survival under medical management was strongly associated with MIDA-Q score, 97±1% with score 0, 95±1% with score 1 to 2, 82±1% with score 3 to 4, 67±1% with score 5 to 6, 60±1% with score 7 to 8, 44±1% with score 9 to 10, 35±1% with score 11 to 12, and 5±4% with MIDA-Q score ≥13, with hazard ratio 1.31 [1.29-1.33] per 1-point increment. Excess mortality with higher MIDA-Q scores persisted after adjustment for age, sex, and EuroScore II (adjusted hazard ratio, 1.13 [1.11-1.15] per 1-point increment). Subgroup analysis showed persistent association of MIDA-Q score with mortality in all possible subsets, in particular, with EuroScore II<1% (hazard ratio, 1.08 [1.02-1.14]) or ≥1% (hazard ratio, 1.11 [1.08-1.13]) and with no/mild DMR (hazard ratio, 1.14 [1.10-1.19]) or moderate/severe DMR (hazard ratio, 1.13 [1.10-1.16], all per 1-point increment with P<0.0001). Nested-model and bootstrapping analyses demonstrated incremental prognostic power of MIDA-Q score (all P<0.0001).

CONCLUSIONS

This large, international cohort of isolated MVP, with prospective DMR quantification in routine practice, demonstrates the wide range of risk factor accumulation and considerable heterogeneity of outcomes after MVP diagnosis. The MIDA-Q score is strongly, independently, and incrementally associated with long-term survival after MVP diagnosis, irrespective of presentation, and is therefore a crucial prognostic instrument for risk stratification, clinical trials, and management of patients diagnosed with all forms of MVP.