Stretch of the papillary insertion triggers reentrant arrhythmia: an in silico patient study.

Background: The electrophysiological mechanism connecting mitral valve prolapse (MVP), premature ventricular complexes and life-threatening ventricular arrhythmia is unknown. A common hypothesis is that stretch activated channels (SACs) play a significant role. SACs can trigger depolarizations or shorten repolarization times in response to myocardial stretch. Through these mechanisms, pathological traction of the papillary muscle (PM), as has been observed in patients with MVP, may induce irregular electrical activity and result in reentrant arrhythmia. Methods: Based on a patient with MVP and mitral annulus disjunction, we modeled the effect of excessive PM traction in a detailed medical image-derived ventricular model by activating SACs in the PM insertion region. By systematically varying the onset of SAC activation following sinus pacing, we identified vulnerability windows for reentry with 1 ms resolution. We explored how reentry was affected by the SAC reversal potential ( E SAC ) and the size of the region with simulated stretch (SAC region). Finally, the effect of global or focal fibrosis, modeled as reduction in tissue conductivity or mesh splitting (fibrotic microstructure), was investigated. Results: In models with healthy tissue or fibrosis modeled solely as CV slowing, we observed two vulnerable periods of reentry: For E SAC of -10 and -30 mV, SAC activated during the T-wave could cause depolarization of the SAC region which lead to reentry. For E SAC of -40 and -70 mV, SAC activated during the QRS complex could result in early repolarization of the SAC region and subsequent reentry. In models with fibrotic microstructure in the SAC region, we observed micro-reentries and a larger variability in which times of SAC activation triggered reentry. In these models, 86% of reentries were triggered during the QRS complex or T-wave. We only observed reentry for sufficiently large SAC regions ( > = 8 mm radius in models with healthy tissue). Conclusion: Stretch of the PM insertion region following sinus activation may initiate ventricular reentry in patients with MVP, with or without fibrosis. Depending on the SAC reversal potential and timing of stretch, reentry may be triggered by ectopy due to SAC-induced depolarizations or by early repolarization within the SAC region.

Characteristic of myocardial work in mitral valve prolapse with versus without mitral annular disjunction: A propensity-matched study.

BACKGROUND: Mitral annular disjunction (MAD) tends to coexist with mitral valve prolapse (MVP) and mitral regurgitation (MR), and is also highly associated with arrhythmias. Myocardial work (MW) analysis is dedicated to estimate myocardial performance by integrating strain analysis and afterload. We aimed to use MW analysis to investigate the cardiac remodeling and dysfunction in MAD, particularly the damage of some segments, and to enhance the understanding of the correlations between MW parameters and VAs within MVP patients. METHODS: A total of 22 consecutive MVP patients with MAD (MAD+) and 44 consecutive MVP patients without MAD (MAD-) (50 ± 11yeas; 18% females) were screened by propensity score matching (PSM), and were divided into subgroups based on MR severity (MR+: Grade 2+; MR-: ≤1), GWI median (GWI ≤ 2079.5 mmHg%; GWI>2079.5 mmHg%), as well as the presence of VAs (VAs+; VAs-). MW parameters consist of global work efficiency (GWE), global work index (GWI), global constructive work (GCW) and global wasted work (GWW). RESULTS: The MAD+ patients had larger LVEDD and LAVI, as well as lower GWE, GWI, and GCW (all P<0.05) compared to the MAD- patients, regardless of similar GLS and regurgitant volume(both P>0.05). When categorized by MR severity, GWI (P = 0.049) and GCW (P = 0.040) were diminished in the MR-MAD+ group. The regional analysis showed MAD+ patients had decreased MW index in the basal (posterior and inferior) and mid (posterior and inferior) segments. Multivariate linear regression showed MAD phenotype, but not MR severity, was independently associated with diminished GWE, GWI, and GCW (all P<0.05). When divided by GWI median, MAD phenotype [OR (95%CI): 5.189 (1.193-22.572), P = 0.028] was an independent predictor of decreased GCW. The receiver-operating characteristic curve identified bileaflet prolapse [AUC (95%CI): 0.664 (0.502-0.825), P = 0.045], and GWI for basal inferior [(AUC (95%CI): 0.679 (0.538-0.819), P = 0.020] as the predictors of the VAs. CONCLUSION: MAD phenotype has the ability to compromise cardiac structure and function, irrespective of volume overload, as evidenced by dilated LV and impaired MW index in basal and mid segments. Excessively decreased regional MW index can identify patients with the high risk of VAs. MW analysis can be a valuable imaging marker for detecting myocardial impairment induced by MAD.

Case report: arrhythmic mitral valve prolapse syndrome-are risk factors underdiagnosed?

Background: Arrhythmic mitral valve prolapse syndrome (ARMV) is a recognized but underdiagnosed disease pattern. Risk factors for ARMV are established but not very well known, and the association of the structural abnormality with ventricular arrhythmias is incompletely understood. Case summary: Here, we present the case of a young man who presented at our hospital for radiofrequency catheter ablation and mitral valve surgery after two episodes of survived sudden cardiac arrest. We discuss the diagnostic and therapeutic strategies that were used. We shine light on the risk factors for ARMV and why early identification is crucial. We address the topic of primary prevention and its limitations. Finally, we discuss different treatment modalities for patients with ARMV. Discussion: More awareness for ARMV is crucial. A consensus statement on clinical management exists, but scientific gaps in prospective data for primary prevention need to be filled and there is a need for a better understanding of the pathogenesis of ARMV.

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.

Mitral Valve Prolapse With Mitral Annular Disjunction Causing Ventricular Tachycardia During a Stress Test: A Case Report.

Mitral valve prolapse (MVP) is a relatively common valvular disorder characterized by displacement of one or both mitral valve leaflets into the left atrium (LA) during systole. Mitral annular disjunction (MAD) is an associated abnormality where a portion of the mitral valve annulus attaches superiorly in the left atrial wall. Although MVP is often considered benign, it can rarely lead to serious complications such as ventricular arrhythmias, especially when MAD is present. Herein, we present a case of a 63-year-old male with MVP and MAD who experienced sustained ventricular tachycardia (VT) during cardiac stress testing. This case underscores the importance of recognizing MVP with MAD as a potential substrate for ventricular arrhythmias, notably under heightened physiological or induced periods of stress.

Age-related changes in mitral annular disjunction: A retrospective analysis using enhanced cardiac CT.

AIMS: The current recognition of mitral annular disjunction (MAD) as an anatomical abnormality potentially associated with ventricular arrhythmias has sparked controversy regarding its prevalence and clinical implications. This study aimed to investigate the prevalence and extent of MAD in individuals with no significant structural abnormalities involving the left heart using enhanced cardiac CT, while also exploring potential factors, such as age, that may be associated with MAD. METHODS: Systolic datasets of cardiac CT from 742 subjects were retrospectively included. MAD was determined by rotating orthogonal multiplanar reconstruction images around the central axis of the mitral annulus. The maximal distance of disjunction (DMAD) and segments involved (SI, 0 to 5 basal segments at left ventricular wall) was quantified to evaluate the extent of separation. RESULTS: In total, 449 (60.5%) had MAD. Subjects with MAD were significantly older (51.3 ± 19.9 years vs. 29.6 ± 20.3 years, P < 0.001). Age was found to be an independent relevant factor for MAD (OR = 1.059; 95%CI: 1.033, 1.085; P < 0.001). Subjects with MAD were then divided into 4 subgroups (G1: ≤20 years, G2: 21-40 years, G3: 41-60 years, G4: ≥61 years). DMAD and SI of each age subgroup were 1.9 ± 0.2 mm, 2.0 ± 1.2 (G1, n = 36), 2.7 ± 0.8 mm, 2.9 ± 1.3 (G2, n = 51), 3.0 ± 0.8 mm, 3.0 ± 1.3 (G3, n = 183), and 3.0 ± 1.0 mm, 3.7 ± 1.1 (G4, n = 179). Age was an independent relevant factor associated with DMAD (R2 = 0.132; ß = 0.014; 95%CI: 0.004, 0.024; P = 0.007) and SI (OR = 1.030; 95%CI: 1.005, 1.055; P = 0.016). CONCLUSIONS: MAD is a common finding on cardiac CT. Its prevalence and extent increase with age.

Mitral annulus disjunction in consecutive patients undergoing cardiovascular 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 cardiovascular 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. MAD was defined as a ≥1 mm displacement between the left atrial wall-mitral valve leaflet junction and the left ventricular wall during end-systole. MAD extent was defined as the maximum longitudinal displacement. Associates of MAD were evaluated at univariable and multivariable regression analysis. The study endpoint, a composite of (aborted) sudden cardiac death, unexplained syncope, and sustained ventricular tachycardia, was evaluated at a 12-month follow-up. RESULTS: Four hundred and forty-one patients 55 ± 18 years, 267/441 (61%) males) were included, and 29/441 (7%) had MVP. The prevalence of MAD ≥1 mm, 4 mm, and 6 mm was 214/441 (49%), 63/441 (14%), and 15/441 (3%), respectively. Patients with MVP showed a higher prevalence of MAD greater than 1 mm (26/29 (90%) vs 118/412 (46%)); p < 0.001), 4 mm (14/29 (48%) vs 49/412 (12%)); p < 0.001), and 6 mm (3/29 (10%) vs 12/412 (3%)); p = 0.03), and a greater MAD extent (4.2 mm, 3.0-5.7 mm vs 2.8 mm, 1.9-4.0 mm; p < 0.001) compared to patients without MVP. 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-electrocardiogram was associated with MAD ≥4 mm and MAD extent (p < 0.05). The presence of MAD ≥1 mm (0.9% vs 1.8%; p = 0.46), MAD ≥4 mm (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 ≥6 mm showed a trend toward a higher likelihood of the study endpoint (6.7% vs 1.2%; p = 0.07). CONCLUSION: MAD of limited severity 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.

Mitral Annulus Disjunction: A Comprehensive Cardiovascular Magnetic Resonance Phenotype and Clinical Outcomes Study.

BACKGROUND: Clinical importance of mitral annulus disjunction (MAD) is not well established. PURPOSE: Characterize a population of MAD all-comers diagnosed by cardiac magnetic resonance imaging (MRI). STUDY TYPE: Retrospective. POPULATION: MAD confirmed in 222 patients, age of 49.2 ± 19.3 years, 126 (56.8%) males. FIELD STRENGTH/SEQUENCE: 1.5 T and 3 T/steady-state free precession and inversion recovery. ASSESSMENT: Clinical history, outcomes, imaging, and arrhythmia data. MAD defined as a separation ≥2 mm between left ventricular myocardium and mitral annulus. Presence and pattern of late gadolinium enhancement (LGE) were analyzed. LGE in the papillary muscles and adjacent to MAD were identified as MAD related. Ventricular arrhythmias (VA) were grouped into non-sustained ventricular arrhythmias (NSVA) or sustained. Cardiovascular death assessed. STATISTICAL TESTS: Differences between baseline characteristics were compared. Univariate regression was used to investigate possible associations between ventricular arrhythmia and cardiovascular death with characteristics associated with the severity of MAD. A multivariable logistic regression included significant variables from the univariate analysis and was performed for MAD-related and global LGE. RESULTS: MAD extent 5.0 ± 2.6 mm. MV annulus expanded during systole for MAD ≥6 mm. Systolic expansion associated with prolapse, billowing, and curling. LGE present in 82 patients (36.9%). Twenty-three patients (10.4%) showed MAD-related LGE by three different observers. No association of LGE with MAD extent (P = 0.545) noted. Follow-up 4.1 ± 2.4 years. No sustained VA observed. In univariable analysis, NSVA was more prevalent in patients with MAD ≥6 mm (33.3% vs. 9.9%), but this was attenuated on multivariate analysis (P = 0.054). The presence of NSVA was associated with global LGE but not MAD-related LGE in isolation (P = 0.750). Three patients died of cardiovascular causes (1.4%) and none had MAD-related LGE. None died of sudden cardiac arrest. CONCLUSION: In patients referred for cardiac MRI, mitral valve dysfunction was associated with MAD severity. Scar was not related to the extent of MAD, but associated with NSVA. The risk of sustained arrhythmias and cardiovascular death was low in this population. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

Phylogenetics and biogeography of the olive family (Oleaceae).

BACKGROUND AND AIMS: Progress in the systematic studies of the olive family (Oleaceae) during the last two decades provides the opportunity to update its backbone phylogeny and to investigate its historical biogeography. We additionally aimed to understand the factors underlying the disjunct distribution pattern between East Asia and both West Asia and Europe that is found more commonly in this family than in any other woody plant families. METHODS: Using a sampling of 298 species out of ca. 750, the largest in a phylogenetic study of Oleaceae thus far, and a set of 36 plastid and nuclear markers, we reconstructed and dated a new phylogenetic tree based on maximum likelihood and Bayesian methods and checked for any reticulation events. We also assessed the relative support of four competing hypotheses [Qinghai-Tibet Plateau uplift (QTP-only hypothesis), climatic fluctuations (Climate-only hypothesis), combined effects of QTP uplift and climate (QTP-Climate hypothesis), and no effects (Null hypothesis)] in explaining these disjunct distributions. KEY RESULTS: We recovered all tribes and subtribes within Oleaceae as monophyletic, but uncertainty in the position of tribe Forsythieae remains. Based on this dataset, no reticulation event was detected. Our biogeographic analyses support the QTP-Climate hypothesis as the likely main explanation for the East-West Eurasian disjunctions in Oleaceae. Our results also show an earlier origin of Oleaceae at ca. 86 Mya and the role of Tropical Asia as a main source of species dispersals. CONCLUSION: Our new family-wide and extensive phylogenetic tree highlights both the stable relationships within Oleaceae, including the polyphyly of the genus Chionanthus, and the need for further systematic studies within the family's largest and most under-sampled genera (Chionanthus and Jasminum). Increased sampling will also help to fine-tune biogeographic analyses across spatial scales and geological times.

Severe tricuspid regurgitation with biannular disjunction requiring surgical treatment: a case report.

Background: Tricuspid annular disjunction (TAD) is an annular disjunction of the right-sided heart. Although TAD is often concomitant with mitral annular disjunction (MAD), it often presents as mitral regurgitation (MR), rather than tricuspid regurgitation (TR). While the clinical significance of MAD has been well-established, there is still little data on TAD. This is a rare case of severe TR due to TAD that appears to be isolated from MAD. Case summary: A 63-year-old female complaining of pre-syncope and dyspnoea on exertion was referred to our department. Initial transthoracic echocardiography showed MR and TR due to tricuspid valve prolapse (TVP). On transoesophageal echocardiography, the TVP consisted of an excessively redundant anterior leaflet, where the annular disjunction and severe regurgitation were formed. She recently underwent mitral and tricuspid valve plasties for symptomatic primary severe TR. Discussion: This case report emphasizes the clinical significance of TAD as a potential cause of severe TR, even without significant MR. Tricuspid annular disjunction progresses more gradually compared with MAD. This case suggests that remodelling of the right atrium, particularly in chronic atrial fibrillation, may contribute to the development of TR. Despite diagnostic challenges due to the flexible and dynamic nature of the tricuspid annulus, this is the first report of TAD-induced severe TR necessitating surgical intervention. Accurately diagnosing TAD remains challenging with current imaging modalities, emphasizing the need for improved diagnostic tools to optimize treatment strategies.

Mitral annular disjunction and its progression during childhood in Marfan syndrome.

AIMS: Data on mitral annular disjunction (MAD) in children with Marfan syndrome (MFS) are sparse. To investigate the diagnostic yield of MAD by echocardiography and cardiac magnetic resonance imaging (CMR), its prevalence and progression during childhood. METHODS AND RESULTS: We included patients <21 years old with MFS, defined by 2010 Ghent criteria and a pathogenic FBN1 variant or ectopia lentis. Two readers measured systolic separation between the mitral valve (MV) posterior hinge point and left ventricular (LV) myocardium on initial and subsequent imaging. MAD was defined as MV-LV separation ≥2 mm, MV prolapse (MVP) as atrial displacement ≥2 mm. Kappa coefficients evaluated echocardiogram-CMR agreement. Bland-Altman and intraclass correlation coefficients (ICCs) assessed inter-rater and inter-modality reliability. Univariable mixed-effects linear regression was used to evaluate longitudinal changes of MAD. MAD was detected in 60% (110/185) eligible patients. MVP was present in 48% (53/110) of MAD and MAD in 90% (53/59) of MVP. MAD detection by CMR and echocardiography had 96% overall agreement (Kappa = 0.89, P < 0.001) and a 0.32 mm estimate bias (95% CI 0.00, 0.65). ICC by echocardiography, CMR, and between modalities were 0.97 (95% CI 0.93, 0.98), 0.92 (95% CI 0.79, 0.97), and 0.91 (95% CI 0.85, 0.94), respectively. MAD was associated with aortic root dilation (P < 0.001). MAD was found in children of all ages, increased +0.18 mm/year (95% CI +0.14, +0.22) during a median duration of 5.5 years (IQR 3.1, 7.5 years). MAD indexed by height yielded a constant value +0.0002 mm/m/year (95% CI -0.0002, +0.0005 mm/m/year). CONCLUSION: MAD was common in pediatric MFS and was associated with aortic root dilation. MAD detection by echocardiography and CMR was highly reliable, suggesting that routine assessment in MFS is feasible. MAD was present in neonates and progressed over time but remained constant when indexing by height. Further studies are needed to evaluate MAD as a biomarker for clinical outcomes in pediatric MFS.

Mitral valve prolapse: arrhythmic risk during pregnancy and postpartum.

BACKGROUND AND AIMS: Arrhythmic mitral valve prolapse (AMVP) is linked to life-threatening ventricular arrhythmias (VAs), and young women are considered at high risk. Cases of AMVP in women with malignant VA during pregnancy have emerged, but the arrhythmic risk during pregnancy is unknown. The authors aimed to describe features of women with high-risk AMVP who developed malignant VA during the perinatal period and to assess if pregnancy and the postpartum period were associated with a higher risk of malignant VA. METHODS: This retrospective international multi-centre case series included high-risk women with AMVP who experienced malignant VA and at least one pregnancy. Malignant VA included ventricular fibrillation, sustained ventricular tachycardia, or appropriate shock from an implantable cardioverter defibrillator. The authors compared the incidence of malignant VA in non-pregnant periods and perinatal period; the latter defined as occurring during pregnancy and within 6 months after delivery. RESULTS: The authors included 18 women with AMVP from 11 centres. During 7.5 (interquartile range 5.8-16.6) years of follow-up, 37 malignant VAs occurred, of which 18 were pregnancy related occurring in 13 (72%) unique patients. Pregnancy and 6 months after delivery showed increased incidence rate of malignant VA compared to the non-pregnancy period (univariate incidence rate ratio 2.66, 95% confidence interval 1.23-5.76). CONCLUSIONS: The perinatal period could impose increased risk of malignant VA in women with high-risk AMVP. The data may provide general guidance for pre-conception counselling and for nuanced shared decision-making between patients and clinicians.

Serial Cardiac Magnetic Resonance Imaging in Patients with Mitral Valve Prolapse-A Single-Center Retrospective Registry.

Background: Mitral valve prolapse (MVP) and mitral annular disjunction (MAD) are common valvular abnormalities that have been associated with ventricular arrhythmias (VA). Cardiac magnetic resonance imaging (CMR) has a key role in risk stratification of VA, including assessment of late gadolinium enhancement (LGE). Methods: Single-center retrospective analysis of patients with MVP or MAD who had >1 CMR and >1 24 h Holter registration available. Data are presented in detail, including evolution of VA and presence of LGE over time. Results: A total of twelve patients had repeated CMR and Holter registrations available, of which in four (33%) patients, it was conducted before and after minimal invasive mitral valve repair (MVR). After a median of 4.7 years, four out of eight (50%) patients without surgical intervention had new areas of LGE. New LGE was observed in the papillary muscles and the mid to basal inferolateral wall. In four patients, presenting with syncope or high-risk non-sustained ventricular tachycardia (VT), programmed ventricular stimulation was performed and in two (50%), sustained monomorphic VT was easily inducible. In two patients who underwent MVR, new LGE was observed in the basal inferolateral wall of which one presented with an increased burden of VA. Conclusions: In patients with MVP and MAD, repeat CMR may show new LGE in a small subset of patients, even shortly after MVR. A subgroup of patients who presented with an increase in VA burden showed new LGE upon repeat CMR. VA in patients with MVP and MAD are part of a heterogeneous spectrum that requires further investigation to establish risk stratification strategies.

Mitral Annular Disjunction in the Context of Mitral Valve Prolapse: Identifying the At-Risk Patient.

Mitral annular disjunction (MAD), a separation between the left atrium/mitral valve annulus and the left ventricular myocardium, is frequently seen in patients with arrhythmic mitral valve prolapse. Although an association exists between MAD and ventricular arrhythmias, little is known regarding the identification of individuals at high risk. Multimodality imaging including echocardiography, computed tomography, cardiac magnetic resonance, and positron emission tomography can play an important role in both the diagnosis and risk stratification of MAD. Due to a paucity of data, clinical decision making in a patient with MAD is challenging and remains largely empirical. Although MAD itself can be corrected surgically, the prevention and treatment of associated arrhythmias may require medical therapy, catheter ablation, and an implantable cardioverter-defibrillator. Prospective data are required to define the role of implantable cardioverter-defibrillators, targeted catheter ablation, and surgical correction in selected, at-risk patients.

Mitral valve surgery in patients with Marfan syndrome.

OBJECTIVE: To review the pathology of the mitral valve (MV) and long-term outcomes of surgery in patients with Marfan syndrome (MFS). PATIENTS AND METHODS: From 1988 through 2020, 60 patients with MFS had surgery to correct mitral regurgitation (MR): 19 had isolated MV surgery, 32 had combined MV and aortic root surgery, and 9 had MV surgery after aortic root surgery. Follow-up was complete for a median of 16.1 years. RESULTS: MV pathology was myxomatous degeneration in all patients and of advanced degree in 78.6% with bileaflet prolapse in 65.5%, mitral annulus disjunction in 57.5%, and mitral annulus calcification in 8.2% of patients. The MV was repaired in 47 patients and replaced in 13. Kaplan-Meier estimates of cumulative mortality at 20 years 21.3% for all patients, 6.7% after MV repair, and 57.8% after replacement (P < .001). MV reoperations were performed in 5 patients: 2 after repair and 3 after replacement. The cumulative incidence rate of reoperations on the MV was 3.8% at 10 years and 11.0% at 20 years in the entire cohort. Among 47 patients who had MV repair, moderate MR developed in 11 patients and severe in 2. Both patients with severe MR underwent MV reoperation. The cumulative incidence rate of recurrent moderate or severe MR after MV repair was 20.4% at 10 years, and 36.5% at 20 years. CONCLUSIONS: MV repair was associated with better survival than MV replacement, but recurrent MR after repair occurred in approximately one-third of the patients at 20 years after surgery.

Description and prevalence of ventricular mitral annular disjunction: variation of normality or pathological variant?

INTRODUCTION AND OBJECTIVES: The aim of this study was to investigate a new variation of the atrial wall-mitral annulus-ventricular wall junction along the mural mitral leaflet and commissures: the ventricular mitral annular disjunction (v-MAD). This new variant is characterized by spatial displacement of the mitral leaflet hinge line by more than 2mm toward the left ventricle. METHODS: We examined a cohort of autopsied human hearts (n=224, 21.9% females, 47.9±17.6 years) from patients without known cardiovascular disease to identify the presence of v-MAD. RESULTS: More than half (57.1%) of the hearts showed no signs of MAD in the mural mitral leaflet or mitral commissures. However, v-MAD was found in 23.6% of cases, located within 20.1% of mural leaflets, 2.2% in superolateral commissures, and 1.3% in inferoseptal commissures. V-MAD was not uniformly distributed along the mitral annulus circumference, with the most frequent site being the P2 scallop (19.6% of hearts). The v-MAD height was significantly greater in mural leaflets than in commissures (4.4 mm±1.2 mm vs 2.1 mm±0.1 mm; P<.001). No specific variations in mitral valve morphology or anthropometrical features of donors were associated with the presence or distribution of v-MADs. Microscopic examinations revealed the overlap of the thin layer of atrial myocardium over ventricular myocardium in areas of v-MAD. CONCLUSIONS: Our study is the first to present a detailed definition and morphometric description of v-MAD. Further studies should focus on the clinical significance of v-MAD to elucidate whether it represents a benign anatomical variant or a significant clinical anomaly.

Evaluation of left ventricular function in patients with mitral annular disjunction using speckle tracking echocardiography.

BACKGROUND: Mitral annular disjunction (MAD) is a structural abnormality characterized by the systolic detachment of the posterior mitral annulus and the ventricular myocardium. It is usually observed coexistent with mitral valve prolapse (MVP) and associated with a mechanical dysfunction despite preserved electrical isolation function of the mitral annulus. This study aimed to evaluate left ventricular (LV) function using speckle tracking echocardiography in MVP patients with MAD. METHODS: This study was designed as a prospective, single-center study including 103 patients with MVP and 40 age- and sex-matched control subjects. Transthoracic echocardiography and cardiac magnetic resonance imaging were performed to assess LV function and MAD presence. RESULTS: MAD (+) MVP (n = 34), MAD (-) MVP (n = 69), and control (n = 40) groups were enrolled in the study. Among the MVP patients, 34 (33%) had MAD. T-negativity in the inferior leads on electrocardiography was more frequent in the MAD (+) group than in the MAD (-) patients (4.3% vs. 20.6%, p = .014). Mitral regurgitation degree, Pickelhaube sign (17.6% vs. 1.4%, p = .005), and late gadolinium enhancement frequency (35.3% vs. 10.6%, p = .002) were significantly higher in MAD (+) patients. MAD (+) patients had significantly impaired global longitudinal strain (-23.1 ±  2.1 vs. -23.5 ± 2.3, p < .001), basal longitudinal strain (BLS) (-19.6 ±  1.5 vs. -20.5 ± 1.9, p < .001), Mid-Ventricular Longitudinal Strain (-22.2 ± 1.7 vs. -23.2 ± 2.2, p < .001) and LA strain (-24.5 ± 3.9 vs. -27.2 ± 3.6, p < .001) when compared to MAD (-) MVP patients, despite similar LV ejection fraction. All these values of MVP patients were also significantly lower than the control group. The mean MAD distance was 7.8 ± 3.2 mm in MAD (+) patients. Patients with two or more symptoms were higher in the MAD (+) group than in the MAD (-) group (4.3% vs. 44.1%, p < .001). CONCLUSION: This study demonstrated a significant decrease in longitudinal strain in MVP patients with MAD, indicating myocardial dysfunction. These findings suggest that MAD may contribute to LV dysfunction and highlight the importance of early detection in younger patients. Further research is needed to explore the functional implications and long-term outcomes of MAD.

The effects of pterygomaxillary disjunction in surgically assisted rapid maxillary expansion: A systematic review and meta-analysis.

OBJECTIVE: This study aims to assess the expansive effects of pterygomaxillary disjunction (PMD) in surgically assisted rapid maxillary expansion (SARME) surgery using a meta-analysis approach. MATERIALS AND METHODS: The study conducted a comprehensive literature search across five databases: PubMed, Scopus, Medline, Embase, and Cochrane, adhering to the PRISMA 2020 guidelines. Dental alterations were assessed using either cone-beam computed tomography (CBCT) or dental casts, while skeletal changes were exclusively measured from CBCT scans. We analysed the dentoskeletal changes between PMD +/- groups and conducted a within-group comparison. The primary focus of the results was on the mean differences observed in pre- and post-operative measurements. RESULTS: Dental expansion was larger in the PMD+ group but not statistically significant. Skeletal expansion showed a significantly larger expansion in the posterior region in the PMD+ group (P = .033). Without PMD, anterior palatal expansion was significantly larger (P = .03), and the buccal tipping of posterior teeth was also significantly larger (P = .011) to achieve acceptable dental expansion outcomes. CONCLUSIONS: Both PMD +/- groups of SARME surgery can achieve satisfactory dental expansion outcomes. However, bone expansion and tooth inclination are also important factors that influence orthodontic treatment and post-expansion stability. By reducing the bony resistance with PMD, larger posterior palatal expansion and more parallel bony expansion are observed. In contrast, without PMD, there is smaller palatal expansion and greater tooth inclination in the posterior region. This could potentially lead to compromised periodontal conditions following expansion.

Mitral annular disjunction in out-of-hospital cardiac arrest patients-a retrospective cardiac MRI study.

BACKGROUND: Mitral annular disjunction (MAD), defined as defective attachment of the mitral annulus to the ventricular myocardium, has recently been linked to malignant arrhythmias. However, its role and prognostic significance in patients requiring cardiopulmonary resuscitation (CPR) remain unknown. This retrospective analysis aimed to describe the prevalence and significance of MAD by cardiac magnetic resonance (CMR) imaging in out-of-hospital cardiac arrest (OHCA) patients. METHODS: Eighty-six patients with OHCA and a CMR scan 5 days after CPR (interquartile range (IQR): 49 days before - 9 days after) were included. MAD was defined as disjunction-extent ≥ 1 mm in CMR long-axis cine-images. Medical records were screened for laboratory parameters, comorbidities, and a history of arrhythmia. RESULTS: In 34 patients (40%), no underlying cause for OHCA was found during hospitalization despite profound diagnostics. Unknown-cause OHCA patients showed a higher prevalence of MAD compared to definite-cause patients (56% vs. 10%, p < 0.001) and had a MAD-extent of 6.3 mm (IQR: 4.4-10.3); moreover, these patients were significantly younger (43 years vs. 61 years, p < 0.001), more often female (74% vs. 21%, p < 0.001) and had fewer comorbidities (hypertension, hypercholesterolemia, coronary artery disease, all p < 0.005). By logistic regression analysis, the presence of MAD remained significantly associated with OHCA of unknown cause (odds ratio: 8.49, 95% confidence interval: 2.37-30.41, p = 0.001) after adjustment for age, presence of hypertension, and hypercholesterolemia. CONCLUSIONS: MAD is rather common in OHCA patients without definitive aetiology undergoing CMR. The presence of MAD was independently associated to OHCA without an identifiable trigger. Further research is needed to understand the exact role of MAD in OHCA patients.