Arrhythmic Mitral Valve Prolapse and Sudden Cardiac Death

The Role of Cardiovascular Magnetic Resonance Imaging in Athletic Individuals-A Narrative Review

Cardiovascular magnetic resonance imaging (MRI) is an advanced cardiac imaging modality that is often required when evaluating athletic individuals. Unrestricted imaging planes, excellent spatial resolution, and a lack of ionising radiation are some of the benefits of this modality. Cardiac MRI has been established as the gold standard imaging modality for morphological assessment, volumetric analysis, and tissue characterisation. Cardiac MRI without any doubt is an excellent diagnostic tool when evaluating athletes with symptoms or those individuals exhibiting equivocal findings at screening. It is also useful for athletes who fall within the grey zone and is especially important among athletes with a suspected or confirmed diagnosis. Cardiac MRI plays a strategic role when adopting a shared decision-making model in athletes with heart disease, tailoring and personalising medical care to the condition and the athlete's wishes. The aim of this review is to provide a comprehensive yet practical overview of the role of cardiac MRI when evaluating athletes in clinic.

Outcomes in Patients With Mitral Annular Disjunction and an Implantable-Cardioverter Defibrillator

BACKGROUND

Mitral annular disjunction (MAD) carries an increased risk of complex ventricular arrhythmias, which can lead to sudden cardiac death. Many of these patients undergo implantable cardioverter defibrillator (ICD) implantation, but their ICD outcomes are not known.

OBJECTIVE

The aim of this study was to assess the outcomes of ICD implantation and the predictors of appropriate ICD therapies in patients with MAD.

METHODS

The study included patients with MAD who underwent ICD implantation. Clinical, electrocardiographic, cardiac imaging, and device therapy data were collected.

RESULTS

Forty-nine patients with MAD and ICD were included. Median age was 49 (21) years, and 29 (59%) were female. 13 (27%) patients underwent ICD implantation for primary prevention and 36 (73%) patients for secondary prevention. Over a median follow-up of 27.3 (35.3) months, 23 (47%) patients received ICD therapies. 18 (37%) patients had appropriate ICD therapies, and 5 (10%) patients had inappropriate ICD shocks. Median time to first appropriate therapy was 22.3 (63.3) months. In patients with a secondary prevention ICD indication, the rate of appropriate ICD therapies was 44%, while in patients with a primary prevention ICD indication, it was 15%. Among patients with appropriate ICD therapies, the first therapies were delivered for monomorphic ventricular tachycardia (VT) in 7 (39%) patients and polymorphic VT or ventricular fibrillation (VF) in 11 (61%) patients. Patients with appropriate ICD therapies were more likely to have a history of SCA (p = 0.003) and/or low left ventricular ejection fraction (LVEF) (p = 0.022) before ICD implantation as compared to patients without appropriate ICD therapies.

CONCLUSIONS

In our cohort of patients with MAD and ICD, appropriate ICD therapies were common. Most appropriate ICD therapies were delivered for polymorphic VT or VF. Larger studies are needed to elucidate the mechanisms of VAs and refine risk stratification in MAD.

Left ventricular rigor mortis interferes with postmortem aortic root geometry

Aortic regurgitation is a common valve disease and can be caused by delineated findings such as fenestrations or hardly discernible alterations of the aortic root geometry. Therefore, aortic regurgitation can be a challenging diagnosis during an autopsy. Cardiac surgeons, however, are confronted with comparable problems during surgery and have developed a refined knowledge of the anatomy of the aortic root including its geometry. Transferring this knowledge from the operating room to the dissection would further complement the panel of postmortem diagnostic tools. To foster translation of the clinical anatomy, the present study assessed the impact of postmortem peculiarities (i.e. myocardial rigor mortis, putrefaction) that might influence aortic root geometry. The aortic root geometry was described by aortic perimeters (basal, sinus, sino-tubular junction, and ascending aorta), effective height (distance from the cusp's free margin to its nadir), geometric height (cusp height), commissural height (distance from the base of an interleaflet triangle to the end of a commissure), and length of the ascending aorta. Data from 140 cases were analyzed (linear regression, comparative testing). Myocardial rigor mortis was associated with smaller basal rings. Weak positive correlations between the duration of the postmortem interval and aortic root dimensions were observed. In summary, postmortem peculiarities, especially the myocardial cadaveric rigidity, influence postmortem aortic root geometry. Despite these circumstances, the current study demonstrates that aortic root geometric assessment, including effective height, is feasible in a postmortem setting. Further studies are needed to elaborate on aortic root geometry as a diagnostic tool in a necropsy setting.

Female athletes: a state-of-the-art review of multiorgan influence of exercise training

Endurance sports have witnessed an increase in female participation, demanding a constant and evolving reassessment of the specific physiological and health implications of female athletes. In the present review, we analyze cardiovascular, hematological adaptations and anthropometry and hormonal fluctuations highlighting sex-specific differences in response to exercise, with estrogen playing a fundamental role in modulating body composition and metabolic processes. Nutritional aspects, in particular energy availability, macronutrient distribution and hydration, are fundamental in supporting training demands and menstrual function. Nevertheless, the repercussions of nutritional deficiencies, interacting in the female athlete triad - which also includes amenorrhea, osteoporosis and eating disorders - underline the importance of comprehensive management strategies. In addition, we comprehensively discuss the multiorgan effects of physical training, highlighting the intersections between sex-specific differences, nutritional needs, and cardiovascular adaptations. Cardiovascular remodeling in female endurance athletes reveals both morphological and functional adaptations, requiring a deep understanding of effective cardiovascular risk assessment and screening. The synthesis of current knowledge highlights the complexity of the physiological landscape of the female athlete practicing endurance sports, requiring ongoing exploration and tailored interventions. In conclusion, this review aims to support a gender-based approach to athletic training and health management and research, intending to optimize performance while safeguarding the well-being of female athletes.

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.

Mitral annular disjunction and mitral valve prolapse: long-term risk of ventricular arrhythmias after surgery

BACKGROUND AND AIMS

Mitral valve prolapse (MVP) is associated with progressive mitral regurgitation (MR) requiring surgical correction. A subset of patients with MVP experience ventricular arrhythmias (VA), and mitral annular disjunction (MAD) has been reported as a risk factor. This study aimed to assess the long-term risk of VA in patients with MAD and MVP undergoing mitral valve surgery for MR.

METHODS

Patients with MVP with moderate or severe degenerative MR undergoing mitral valve surgery (repair or replacement) in 2010-22 at Karolinska University Hospital were included. Mitral annular disjunction length, referring to true MAD, was measured at end systole on pre- and post-operative transthoracic echocardiography. The primary outcome consisted of VA including hospitalizations, outpatient visits or ablation for confirmed sustained or non-sustained ventricular tachycardia, or high burden of premature ventricular complexes and assessed from medical records.

RESULTS

Of 599 patients undergoing mitral valve surgery, 96 (16%) had pre-operative MAD. The median MAD length was 8.0 [inter-quartile range (IQR) 5.0-10.0] mm. Compared with patients without MAD, patients with MAD were younger (55 ± 15 vs 63 ± 11 years), were more often women (31% vs 17%), and had more Barlow's disease (70% vs 27%). Mitral annular disjunction was surgically corrected in all patients. During a median follow-up time of 5.4 (IQR 2.8-7.5) years, patients with pre-operative MAD had a higher risk of VA (hazard ratio adjusted for age and sex 3.33, 95% confidence interval 1.37-8.08) regardless of repair/replacement (Pinteraction = .18).

CONCLUSIONS

Mitral annular disjunction in patients with MVP and MR was associated with a three-fold increased long-term risk of VA post-mitral valve surgery, despite anatomical correction of MAD.

Arrhythmic Mitral Valve Prolapse: Pathophysiology, Diagnostics, and Management Strategies

Mitral valve prolapse (MVP) is a common disease in which ventricular arrhythmias/sudden cardiac death can be the first symptom of presentation. This review article explores the current understanding of underlying pathological mechanisms leading to an increased risk for ventricular arrhythmias in the setting of MVP and elaborates on the current evidence regarding the diagnosis and management of the disease.

Does Preliminary Chest Shape Assessment Improve the Prognostic Risk Stratification of Individuals with Mitral Annular Disjunction? A Case Report and Narrative Review

Background: Mitral annular disjunction (MAD), a mitral annular abnormality involving the whole mitral valve annulus circumference, commonly detected in individuals with mitral valve prolapse (MVP), has been recently recognized as a potential risk factor for malignant ventricular arrhythmias (VAs) and sudden cardiac death. Recent evidence indicates that a multimodality imaging assessment comprehensive of echocardiography, cardiac magnetic resonance (CMR), and cardiac computed tomography angiography (CCTA) may improve MAD detection. To date, no previous author has considered the potential influence of chest wall conformation on MAD presence. Considering the strong association between MVP and anterior chest wall deformities and the increased prevalence of MAD among MVP individuals, we have hypothesized that MAD presence might be more frequently detected among MVP individuals with a narrow anteroposterior (A-P) thoracic diameter and/or concave-shaped chest wall conformation, as noninvasively assessed by the modified Haller index (MHI). Methods: Herein, we present a case of MVP female with relevant MAD distance and moderate mitral regurgitation (MR) who underwent a diagnostic study comprehensive of transthoracic echocardiography, transesophageal echocardiography, CMR, CCTA, and exercise stress echocardiography. Results: The patient was found with a concave-shaped chest wall conformation (MHI > 2.5) and narrow A-P thoracic diameter (<13.5 cm), with a moderate and non-hemodynamically significant MR, without areas of LGE on CMR and with low arrhythmic profile. Conclusions: A preliminary chest shape assessment by the MHI might improve the prognostic risk stratification of MVP patients with MAD, potentially identifying a benign phenotype of MVP individuals, i.e., those with a narrow A-P thoracic diameter.

Clinical Considerations for Competitive Sports Participation for Athletes With Cardiovascular Abnormalities: A Scientific Statement From the American Heart Association and American College of Cardiology

COLLABORATORS

Larry A. Allen, MD, MHS, FAHA, FACC; Mats Börjesson, MD, PhD, FACC; Alan C. Braverman, MD, FACC; Julie A. Brothers, MD; Silvia Castelletti, MD, MSc, FESC; Eugene H. Chung, MD, MPH, FHRS, FAHA, FACC; Timothy W. Churchill, MD, FACC; Guido Claessen, MD, PhD; Flavio D'Ascenzi, MD, PhD; Douglas Darden, MD; Peter N. Dean, MD, FACC; Neal W. Dickert, MD, PhD, FACC; Jonathan A. Drezner, MD; Katherine E. Economy, MD, MPH; Thijs M.H. Eijsvogels, PhD; Michael S. Emery, MD, MS, FACC; Susan P. Etheridge, MD, FHRS, FAHA, FACC; Sabiha Gati, BSc (Hons), MBBS, PhD, MRCP, FESC; Belinda Gray, BSc (Med), MBBS, PhD; Martin Halle, MD; Kimberly G. Harmon, MD; Jeffrey J. Hsu, MD, PhD, FAHA, FACC; Richard J. Kovacs, MD, FAHA, MACC; Sheela Krishnan, MD, FACC; Mark S. Link, MD, FHRS, FAHA, FACC; Martin Maron, MD; Silvana Molossi, MD, PhD, FACC; Antonio Pelliccia, MD; Jack C. Salerno, MD, FACC, FHRS; Ankit B. Shah, MD, MPH, FACC; Sanjay Sharma, BSc (Hons), MBChB, MRCP (UK), MD; Tamanna K. Singh, MD, FACC; Katie M. Stewart, NP, MS; Paul D. Thompson, MD, FAHA, FACC; Meagan M. Wasfy, MD, MPH, FACC; Matthias Wilhelm, MD.

This American Heart Association/American College of Cardiology scientific statement on clinical considerations for competitive sports participation for athletes with cardiovascular abnormalities or diseases is organized into 11 distinct sections focused on sports-specific topics or disease processes that are relevant when considering the potential risks of adverse cardiovascular events, including sudden cardiac arrest, during competitive sports participation. Task forces comprising international experts in sports cardiology and the respective topics covered were assigned to each section and prepared specific clinical considerations tables for practitioners to reference. Comprehensive literature review and an emphasis on shared decision-making were integral in the writing of all clinical considerations presented.

Clinical Considerations for Competitive Sports Participation for Athletes With Cardiovascular Abnormalities: A Scientific Statement From the American Heart Association and American College of Cardiology

This American Heart Association/American College of Cardiology scientific statement on clinical considerations for competitive sports participation for athletes with cardiovascular abnormalities or diseases is organized into 11 distinct sections focused on sports-specific topics or disease processes that are relevant when considering the potential risks of adverse cardiovascular events, including sudden cardiac arrest, during competitive sports participation. Task forces comprising international experts in sports cardiology and the respective topics covered were assigned to each section and prepared specific clinical considerations tables for practitioners to reference. Comprehensive literature review and an emphasis on shared decision-making were integral in the writing of all clinical considerations presented.

Echocardiography screening of German military pilot applicants as an example for high-hazard occupations

Introduction

Pre-employment screening is of utmost importance in high-risk occupations for the early diagnosis and prevention of cardiac and non-cardiac disease, and for risk mitigation. Recommendations for echocardiography screening, however, are contradictory. It was the aim of this study to retrospectively analyze echocardiography data from German military pilot applicant screening to find out in how many cases cardiac disease was diagnosed, and how often the diagnosis influenced aeromedical decision making.

Methods

6,110 screening echocardiographies from German military pilot applicants, 5,923 were male, examined between January 2007 and June 2020 were retrospectively analyzed for findings and their impact on aeromedical decisions.

Results

During a 14.5-year period, 4,477 out of 6,110 screening echocardiograms were normal. The remaining 1,633 applicants revealed a total of 1,962 abnormalities, mainly consisting of minor tricuspid and mitral valve regurgitations (81.9%). Due to echocardiography findings, 80 applicants (1.3%) were unfit for flying duties, 9 (0.1%) were fit with limitations, and 1,544 (25.3%) were fit with findings that had to be monitored over time, but which were not aeromedically relevant. The most common diagnoses leading to disqualification or limitations were bicuspid aortic valve with or without aortic regurgitation (84.9%) and mitral valve prolapse with or without regurgitation (9.3%).

Conclusion

Percentages of abnormal findings were similar to other studies. Aeromedical assessments based on those findings, however, were slightly different, as they depend on national employment policies. As a consequence, the usefulness of echocardiography may vary between different countries and different professions, depending on the acceptance of certain findings for employment.

Characteristics of Patients With the Arrhythmogenic Mitral Valve Prolapse Syndrome and Sudden Cardiac Arrest and Sustained Ventricular Arrhythmias

BACKGROUND

Patients with arrhythmogenic mitral valve prolapse syndrome are at increased risk for life-threatening ventricular arrhythmias, but studies have been limited by small sample sizes. We sought to assemble an international arrhythmogenic mitral valve prolapse syndrome registry to delineate the clinical, imaging, and treatment characteristics of patients with arrhythmogenic mitral valve prolapse syndrome who survived sudden cardiac arrest (SCA) or had sustained ventricular tachycardia (VT) or ventricular fibrillation.

METHODS

In this descriptive registry, we characterized patients with arrhythmogenic mitral valve prolapse syndrome who survived SCA, sustained VT, or ventricular fibrillation. Deidentified data were abstracted locally and combined centrally.

RESULTS

We included 148 patients who had SCA or VT/ventricular fibrillation. Patients had a mean age of 43.7±15.4 years; 68% were women, 73% had bileaflet prolapse, 65% had mitral annular disjunction, 67% had nonsustained VT, and 59% had inferolateral T-wave inversions. Syncope (n=54, 48%) and anterolateral T-wave inversion (n=26, 22%) were relatively common. Catheter ablation was performed in 50 (35%) patients for premature ventricular complexes and in 18 (17.7%) patients for VT. Sites of origin for arrhythmias were commonly in the papillary muscles, fascicles, mitral annulus, and inferior/inferolateral left ventricle.

CONCLUSIONS

In this international descriptive registry of patients with arrhythmogenic mitral valve prolapse syndrome and SCA, patients were young, women, and had bileaflet mitral valve prolapse, mitral annular disjunction, inferolateral T-wave inversions, and nonsustained VT. A history of syncope and anterolateral T-wave inversions was relatively common in patients who survived SCA or sustained VT/ventricular fibrillation.

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.

Are the Cardiovascular Benefits and Potential Risks of Physical Activity and Exercise Dependent on Race, Ethnicity, or Sex?

Physical activity (PA) is established as a cornerstone of cardiovascular health, however, disparities in participation exist across sociocultural groups, which in turn affect cardiovascular outcomes. Evidence suggests that although the positive cardiovascular effects of exercise are consistent across populations, notable differences in the magnitude of these benefits exist for racial and ethnic minorities and the female sex. Women derive greater protection from PA compared with men, with reduced rates of sudden cardiac death. In this review we examine the complex interplay of race and/or ethnicity and sex on the cardiovascular benefits associated with PA and exercise, cardiovascular adaptations to exercise, risks of sudden cardiac death, and "excessive" volume of exercise. Understanding these factors is crucial for developing targeted interventions to promote cardiovascular health and offset disparities.

Interpretation and management of T wave inversion in athletes: An expert opinion statement of the Italian Society of Sports Cardiology (SICSPORT)

T wave inversion (TWI) on the electrocardiogram (ECG) is a relatively common finding in athletes. It poses a diagnostic challenge, as it can indicate either a benign physiological pattern or an early sign of serious cardiac pathology. This expert opinion statement provides a comprehensive review of the current understanding of TWI in athletes, emphasizing the importance of its localization, associated clinical features, and demographic factors in guiding its interpretation and management. We explore the potential causes of TWI, including physiological adaptations such as the juvenile pattern and training-induced repolarization variants, as well as pathological conditions like cardiomyopathies, ion channel diseases, and other cardiac abnormalities. Additionally, we discuss the implications of TWI in different ECG leads-anterior, inferior, and lateral-and the diagnostic work-up needed to exclude underlying disease. The importance of follow-up in athletes with TWI is highlighted, particularly for young athletes, to monitor the potential development of cardiomyopathy. Finally, we address considerations for sports eligibility in athletes with TWI, stressing the need for a balanced approach that ensures athlete safety without imposing unnecessary restrictions and investigations.

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.

Left ventricular hypertrophy and ventricular ectopy in mitral valve prolapse

BACKGROUND

Sudden deaths ascribed to mitral valve prolapse (MVP) have increased ventricular mass on autopsy. It is unknown if left ventricular hypertrophy (LVH) is a risk factor for ventricular arrhythmia in MVP.

METHODS

We studied all 629 patients aged 18-90 years with MVP on echocardiography between 2016 and 19 at our institution. Echocardiograms were reviewed for LVH, ventricular size and function, and valvular pathology. Complex or frequent ventricular ectopy (cfVE) was defined as ≥ 2 premature ventricular complexes (PVC) on a 10-s ECG or > 1 % PVC burden or non-sustained ventricular tachycardia on ambulatory ECG. Multivariable logistic regression and cox proportional hazards regression were used to assess the relationships between LVH, mitral valve structural features, and cfVE in MVP.

RESULTS

LVH was present in 141 (22.4 %) patients. Of those with LVH, 44 (31.2 %) had cfVE compared to 87 (17.8 %) without LVH (p = 0.001). Independent predictors of cfVE were mitral annular disjunction (OR [95 % CI] 2.34 [1.54-3.56]), bileaflet prolapse (1.78 [1.19-2.66]), heart failure (1.79 [1.15-2.79]), lower ejection fraction (0.18 [0.04-0.83]), coronary artery disease (1.58 [1.04-2.39]), and T-wave inversion (1.51 [1.03-2.22]). However, LVH was not independently associated with cfVE (1.22 [0.82-1.83], p = 0.32).

CONCLUSION

Left ventricular hypertrophy is not an independent risk factor for ventricular arrhythmia in MVP. Ventricular arrhythmogenesis in MVP is predominantly determined by mitral morphological factors and heart failure. Further work is required to better understand the predisposition to sudden death of patients with MVP and increased ventricular mass.

Cardiovascular magnetic resonance imaging in mitral valve disease

This paper describes the role of cardiovascular magnetic resonance (CMR) imaging in assessing patients with mitral valve disease. Mitral regurgitation (MR) is one of the most prevalent valvular heart diseases. It often progresses without significant symptoms, leading to left ventricular overload, dysfunction, frequent decompensated heart failure episodes, and excess mortality. Cardiovascular magnetic resonance assessment is recommended for MR when routine ultrasound imaging information is insufficient or discordant. A well-planned CMR can provide an in-depth assessment of the mitral valve apparatus, leaflet morphology, and papillary muscles. In addition, it can precisely inform the impact of MR on left atrial and ventricular remodelling. The review aims to highlight established and emerging techniques for morphological assessment, flow assessment (including regurgitation and stenosis), myocardial assessment, and haemodynamic assessment of mitral valve disease by CMR. It also proposes a simplified clinical flow chart for CMR assessment of the mitral valve.

Outcomes of patients with mitral annular disjunction undergoing mitral valve repair†

OBJECTIVES

Mitral annular disjunction (MAD) is an abnormal displacement of the posterior mitral leaflet into the left atrial wall, potentially leading to left ventricular dysfunction, malignant ventricular arrhythmias (VA) and sudden cardiac death. This study investigates the outcomes of patients with and without MAD undergoing mitral valve repair for valve prolapse (MVP).

METHODS

The study retrospectively collected a single-center experience from 2021 to 2023 on 326 consecutive patients undergoing mitral valve repair for MVP. Patients were divided into two groups according to the presence of MAD. After propensity score matching 1:1, two comparable groups of 50 patients were obtained. Primary endpoints included hospital survival and early failure of the repair. Composite secondary endpoint included major adverse cardiac events (MACEs) such as reoperation, residual regurgitation ≥2, severe postoperative left ventricle (LV) dysfunction requiring prolonged (>3 days) inotropic support, cardiac arrhythmias and overall survival.

RESULTS

After matching, there were no significant differences between the groups in terms of preoperative characteristics. Hospital mortality was 0% in both groups, and there were no significant differences in terms of early reoperation (0%) or residual mitral regurgitation ≥2 or major atrial/VA. Nevertheless, patients with MAD presented a greater need for prolonged inotropic and mechanical circulatory support (IABP/ECMO): No-MAD 0% vs MAD 10% (P = 0.050). However, the composite outcome at midterm follow-up was similar between the groups.

CONCLUSIONS

Mitral valve repair in patients with MAD was associated with a significantly higher incidence of early LV dysfunction requiring mechanical support. However, no difference was found in terms of survival at follow-up.

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.

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.

Arrhythmogenic Mitral Valve Prolapse Revisited: A Not Uncommon Cause of Youthful Sudden Death in Athletes and Women

BACKGROUND

Sudden deaths (SDs) in young people, including competitive athletes, albeit uncommon, are usually attributable to genetic, congenital or acquired cardiovascular conditions. However, it is under-appreciated that mitral valve prolapse (MVP), a relatively common valvular heart disease, is associated with SD in this youthful population.

METHODS

Forty-three MVP-related SDs were identified from 2 large cardiovascular registries with pathologic, clinical, and demographic findings reported.

RESULTS

Events occurred in both sexes, but females were unexpectedly common (49%); median age was 22 ± 8 years, and 29 (67%) were engaged in competitive sports, including 17 with preparticipation examination. Of the 43 MVP cases, 21 died suddenly during or just after vigorous exercise, including 6 during organized sports. Sixteen (37%) had been evaluated by a cardiologist, resulting in confirmed MVP diagnosis in 11. Pathologic findings characteristic of MVP included bileaflet myxomatous involvement (in all cases) and areas of interstitial or replacement myocardial fibrosis (in 79%), most evident in posterolateral left ventricular wall.

CONCLUSIONS

Arrhythmogenic myxomatous degeneration (MVP) is an under-recognized cause of SD in young people, including competitive athletes, disproportionally affecting females and requires a high index of clinical suspicion. Frequency of left ventricular fibrosis in these young people with MVP suggests a mechanism for ventricular tachyarrhythmias and SD, relevant to future risk stratification.

Arrhythmic mitral valve complex: diagnostic and therapeutic approach

El prolapso valvular mitral arrítmico es una condición implicada en casos de muerte súbita cardiaca inexplicable que recientemente ha tomado importancia debido a los métodos diagnósticos actuales. Sin embargo, ya que la presencia de prolapso valvular mitral se ha considerado un hallazgo benigno, sus implicaciones arrítmicas han sido subestimadas. La importancia de la presente revisión es destacar parámetros clínicos y de gabinete que permitan identificar individuos con riesgo arrítmico mediante una estratificación apropiada, para así poder aplicar medidas terapéuticas oportunas y evitar desenlaces fatales.

Prevalence of Diastolic and Systolic Mitral Annular Disjunction in Patients With Mitral Valve Prolapse

BACKGROUNDS

Mitral annular disjunction (MAD) is commonly evaluated at end systole. However, a systolic-only disjunction is merely apparent, and 2 distinct phenotypes have been identified: True-MAD (atrial displacement of the posterior leaflet in diastole and systole) and Pseudo-MAD (apparent displacement in systole only). The prevalence of True-MAD and Pseudo-MAD in mitral valve prolapse (MVP) is not known. The aim of this study was to assess the prevalence of True-MAD and Pseudo-MAD in myxomatous MVP patients by transthoracic echocardiography (TTE) and to validate TTE compared to cardiac magnetic resonance (CMR; reference standards).

METHODS

Consecutive patients who underwent TTE for MVP were included. Mitral annular phenotype was evaluated in the TTE parasternal long-axis view. Accuracy (against CMR) and intra-/interrater reliability of TTE were also assessed.

RESULTS

Six hundred three consecutive patients were included. The prevalence of True-MAD and Pseudo-MAD was 7% (42) and 37% (221) (P < .05), respectively. Accordingly, 221 of 263 (84%) patients classically classified as "MAD" would have been reclassified as Pseudo-MAD. Pseudo-MAD prevalence and systolic length increased with higher mitral regurgitation (MR) severity (23% for mild MR, 36% for moderate MR, 44% for severe MR [P < .05]; 6 ± 2 mm for mild MR; 8 ± 2 mm for moderate MR; 10 ± 2 mm for severe MR [P < .05]), while True-MAD prevalence was consistent across MR grades. Pseudo-MAD was linked to systolic curling and Pickelhaube. Transthoracic echocardiography showed an overall accuracy of 0.89 (Cohen k 0.80), a substantial interrater agreement of 0.87 (k = 0.76), and an almost perfect intrarater agreement of 0.93 (k = 0.85).

CONCLUSIONS

True-MAD, unlike Pseudo-MAD, is rare in patients with MVP. Pseudo-MAD is associated with the grade of MR and other echocardiographic features of advanced myxomatous degeneration. Transthoracic echocardiography is an accurate and reliable first-line method to assess mitral annulus morphology in MVP.

Papillary Muscles of the Left Ventricle: Integrating Electrical and Mechanical Dynamics

BACKGROUND

Papillary muscles are structures integrated into the mitral valve apparatus, having both electrical and mechanical roles. The importance of the papillary muscles (PM) is mainly related to cardiac arrhythmias and mitral regurgitation. The aim of this review is to offer an overview of the anatomy and physiology of the papillary muscles, along with their involvement in cardiovascular pathologies, including arrhythmia development in various conditions and their contribution to secondary mitral regurgitation.

METHODS

A literature search was performed on PubMed using the following relevant keywords: papillary muscles, mitral valve, arrhythmia, anatomy, and physiology.

RESULTS

During the cardiac cycle, papillary muscles have continuous dimensional and pressure changes. On one hand, their synchrony or dyssynchrony impacts the process of mitral valve opening and closure, and on the other hand, the pressure changes can trigger electrical instability. There is increased awareness of papillary muscles as an arrhythmic source. Arrhythmias arising from PM were found in patients with or without structural heart disease, via Purkinje fibres, due to increased automaticity or triggered activity.

CONCLUSIONS

Despite the interest in mitral valve physiology, there are still many unknowns in relation to the papillary muscles, especially with regard to their role in arrhythmogenesis and the pathogenesis of mitral regurgitation.

Cardiovascular magnetic resonance in patients with mitral valve prolapse

With a prevalence of 2-3% in the general population, mitral valve prolapse (MVP) is the most common valvular heart disease. The clinical course is benign in the majority of patients, although severe mitral regurgitation, heart failure, and sudden cardiac death affect a non-negligible subset of patients. Imaging of MVP was confined to echocardiography until a few years ago when it became apparent that cardiovascular magnetic resonance (CMR) could offer comparative advantages for detecting and quantifying mitral valve abnormalities alongside tissue myocardial characterization. The present review highlights the growing body of evidence supporting the role of CMR in patients with MVP. Based on the recent literature, CMR appears not as a simple alternative to echocardiography in patients with poor acoustic windows, but as a complementary imaging modality instrumental for better quantifying mitral valve abnormalities, mitral regurgitation severity, ventricular remodeling, and myocardial tissue changes. In this respect, pivotal CMR studies highlight that mitral annular disjunction and myocardial fibrosis by late gadolinium enhancement are associated with a heightened risk of life-threatening ventricular arrhythmias (arrhythmic MVP). We also delineate how these and other markers (e.g., the severity of mitral regurgitation) could enable a personalized risk assessment in patients with MVP and implement clinical decision-making. Here, we provide a comprehensive review of the current literature, with an emphasis on the arrhythmic MVP phenotype. The review also provides some practical suggestions on how to carry out a dedicated CMR protocol in MVP and composes a thorough report to inform clinicians on key aspects of this valvular heart disease.

Prevalence of Mitral Annular Disjunction at Cardiac MRI: Results from a Multicenter Registry

Purpose To determine the prevalence of mitral annular disjunction (MAD) in patients undergoing cardiac MRI for various clinical indications and to assess the association of MAD with arrhythmia, mitral valve prolapse (MVP), and myocardial alteration. Materials and Methods This study analyzed data from a retrospective observational registry of consecutive patients undergoing cardiac MRI for different clinical indications. Cardiac MRI examinations were performed from January 2019 to June 2019 at 13 Italian hospitals. Images underwent double reading by expert cardiac radiologists from the enrolling center and the core laboratory to assess the presence of MAD. Presence and maximum length of MAD and its association to MVP pattern, functional and structural myocardial alteration, and arrhythmia were evaluated using nonparametric and parametric tests. Logistic regression models were used to identify predictors of arrhythmia. Results Cardiac MRI studies from 2611 consecutive patients (1730, 66% male; median age, 53 years; IQR, 39-65 years) were evaluated. Prevalence of MAD was 5.44% (142 of 2611). MAD was an incidental finding in 74.6% (106 of 142) of patients. Patients with MAD had a higher prevalence of arrhythmias compared with patients without MAD (40% [57 of 142] vs 18% [444 of 2469]; P < .001). Patients with MAD and bileaflet MVP showed a longer MAD compared with patients with single-leaflet or absent MVP (median, 7 mm [IQR, 3-9.5 mm] vs 4 mm [IQR, 3-5 mm]; P < .001), a higher prevalence of systolic curling (75% [21 of 28] vs 30.7% [35 of 114]; P < .001), higher extracellular volume values (30% [IQR, 28%-32%] vs 27% [IQR, 25%-30%]; P = .04), and a higher prevalence of arrhythmia (64.2% [18 of 28] vs 34.2% [39 of 114]; P = .006). MAD length of at least 5 mm was an independent predictor of arrhythmia (odds ratio 3.96; 95% CI: 1.93, 8.15; P < .001). Conclusion MAD was a frequent incidental finding on cardiac MRI scans from a multicenter registry. MAD length of at least 5 mm and coexisting bileaflet MVP showed a higher risk of arrhythmia. Keywords: MR Imaging, Cardiac, Mitral Annular Disjunction Supplemental material is available for this article. ©RSNA, 2024.

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.

Role of cardiac magnetic resonance in stratifying arrhythmogenic risk in mitral valve prolapse patients: a systematic review and meta-analysis

OBJECTIVES

To perform a systematic review and meta-analysis of studies investigating the diagnostic value of cardiac magnetic resonance (CMR) features for arrhythmic risk stratification in mitral valve prolapse (MVP) patients.

MATERIALS AND METHODS

EMBASE, PubMed/MEDLINE, and CENTRAL were searched for studies reporting MVP patients who underwent CMR with assessment of: left ventricular (LV) size and function, mitral regurgitation (MR), prolapse distance, mitral annular disjunction (MAD), curling, late gadolinium enhancement (LGE), and T1 mapping, and reported the association with arrhythmia. The primary endpoint was complex ventricular arrhythmias (co-VAs) as defined by any non-sustained ventricular tachycardia, sustained ventricular tachycardia, ventricular fibrillation, or aborted sudden cardiac death. Meta-analysis was performed when at least three studies investigated a CMR feature. PROSPERO registration number: CRD42023374185.

RESULTS

The meta-analysis included 11 studies with 1278 patients. MR severity, leaflet length/thickness, curling, MAD distance, and mapping techniques were not meta-analyzed as reported in < 3 studies. LV end-diastolic volume index, LV ejection fraction, and prolapse distance showed small non-significant effect sizes. LGE showed a strong and significant association with co-VA with a LogORs of 2.12 (95% confidence interval (CI): [1.00, 3.23]), for MAD the log odds-ratio was 0.95 (95% CI: [0.30, 1.60]). The predictive accuracy of LGE was substantial, with a hierarchical summary ROC AUC of 0.83 (95% CI: [0.69, 0.91]) and sensitivity and specificity rates of 0.70 (95% CI: [0.41, 0.89]) and 0.80 (95% CI: [0.67, 0.89]), respectively.

CONCLUSIONS

Our study highlights the role of LGE as the key CMR feature for arrhythmia risk stratification in MVP patients. MAD might complement arrhythmic risk stratification.

CLINICAL RELEVANCE STATEMENT

LGE is a key factor for arrhythmogenic risk in MVP patients, with additional contribution from MAD. Combining MRI findings with clinical characteristics is critical for evaluating and accurately stratifying arrhythmogenic risk in MVP patients.

KEY POINTS

MVP affects 2-3% of the population, with some facing increased risk for arrhythmia. LGE can assess arrhythmia risk, and MAD may further stratify patients. CMR is critical for MVP arrhythmia risk stratification, making it essential in a comprehensive evaluation.

Interstitial fibrosis and arrhythmic mitral valve prolapse: Unraveling sex-based differences

BACKGROUND

Interstitial fibrosis as quantified by cardiovascular magnetic resonance (CMR) has been demonstrated in arrhythmic mitral valve prolapse (AMVP), a condition with known female predominance. Prior studies of interstitial fibrosis in AMVP have only included cases with significant mitral regurgitation (MR) or mitral annular disjunction (MAD), limiting our understanding of alternative arrhythmic mechanisms in mitral valve prolapse (MVP). We sought to evaluate the association between interstitial fibrosis and AMVP, regardless of MAD and without severe MR, while also investigating the contribution of sex to this association.

METHODS

We performed research-based contrast CMR in consecutive individuals with MVP between 2019 and 2022. Extracellular volume fraction (ECV%), a surrogate marker for interstitial fibrosis, was quantified using T1 mapping in the basal and mid-left ventricular slices. Replacement fibrosis was assessed using late gadolinium enhancement (LGE). AMVP was defined as MVP with frequent premature ventricular contractions and/or non-sustained/sustained ventricular tachycardia (VT) or fibrillation (VF).

RESULTS

We identified 65 MVP cases without severe MR (30 [46%] women, 22 [34%] no/trace, 30 [44%] mild, and 13 [21%] moderate MR) and with adequate ECV% measurement. Among these, 38% were classified as AMVP, including two cases of aborted VF arrest, both in premenopausal females. Global ECV% was significantly higher in AMVP vs non-AMVP (31% [27-33] vs 27% [23-30], p = 0.002). In the AMVP group, higher segmental ECV% was not limited to the inferolateral/inferior walls, typically subject to myocardial traction by the prolapsing leaflets/MAD but was more diffuse and involved atypical segments such as the anterior/anterolateral walls (p < 0.05). The association between AMVP and global ECV% was driven by female sex (32% [30-34] vs 27% [25-30], p = 0.002 in females; 28% [23-32] vs 26% [23-30], p = 0.41 in males). ECV% remained independently associated with an increased risk of arrhythmic events, including VT/VF (p < 0.01), even after adjustment for cardiovascular risk factors, MAD, and LGE (p < 0.01).

CONCLUSION

In MVP without significant MR, interstitial fibrosis by CMR is associated with an increased risk of arrhythmic events, suggesting a primary myopathic process. The selective association between interstitial fibrosis and AMVP in females may explain why severe arrhythmic complications are more prevalent among women.

Mitral Annular Disjunction Associated with Ventricular Dilation in Pediatric Marfan Syndrome: A Cardiovascular Magnetic Resonance Study

BACKGROUND

Mitral annular disjunction (MAD) has increasingly been recognized as a marker for adverse cardiovascular events in Marfan syndrome (MFS). As recent adult data links MFS with left ventricular (LV) dilation and reduced ejection fraction (LVEF), we hypothesized that MAD may be associated with LV dilation in pediatric MFS patients.

METHODS

A retrospective analysis was performed among MFS patients < 19 years old at initial cardiac MRI (CMR). MAD and mitral valve prolapse (MVP) were assessed by CMR or most proximate echo. CMR-derived left ventricular end-diastolic (LVEDV) and end-systolic (LVESV) volumes were measured. Indexed volumes, absolute and indexed z-scores, and LVEF were calculated. The combined volume load from mitral and aortic regurgitation was indexed to LV stroke volume, allowing exclusion of patients with greater than mild volume load or prior MV intervention. MAD association with LV volumes and z-scores was then assessed.

RESULTS

Forty-two patients were analyzed (median age 13.5 years old, IQR [10.9, 15.3]). MAD was present in 28 patients (66.7%), and MVP was present in 13 patients (31.0%). Absolute LVEDV z-score was > 2 in 35.7% of patients, LVESV z-score was > 2 in 42.9%, and LVEF was < 55% in 45.2%. In multivariable analysis including MVP, MAD remained independently associated with elevated absolute LVESV z-score > 2 (RR 3.88, 95% CI 1.02-14.69, p = 0.046).

CONCLUSION

MAD was associated with CMR-derived volume-load-independent LV dilation among pediatric MFS patients. Prospective studies are needed to further understand this association and its relationship with LV dilation over time.

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.

Circadian (diurnal/nocturnal) pattern of cardiac arrhythmias

Circadian rhythms follow 24-hour biological cycle patterns controlled by internal biological or circadian clocks that optimize organismal homeostasis according to predictable environmental changes. These clocks are found in virtually all cells in the body, including cardiomyocytes. Triggers for and/or the occurrence of sudden cardiac death (SCD) and cardiac arrhythmias seem to follow such daily patterns. This review highlights data from studies exploring the role of day/night rhythms in the timing of arrhythmic events, studies describing the environmental, behavioral, and circadian mechanisms regulating cardiac electrophysiology focusing on the circadian pattern of arrhythmias and SCD. Mechanisms involved relate to circadian control of electrophysiological properties, vagal tone, and sleep disorders, as well as the potential interaction and synergism among these factors. By studying the diurnal variations of arrhythmias, therapy can be improved by optimally timing it to their circadian pattern and a person's internal body clock time. Potential treatment targets for arrhythmias with nocturnal onset may include upstream therapy for underlying comorbidities, type and timing of drug intake, pulmonary vein isolation, ablation of the ganglionated plexus, and autonomic nervous system control. Thus, specific history-taking, screening, and diagnostic workup are recommended to identify and characterize comorbidities and potential contributors to nocturnal arrhythmias, such as obesity, advanced age, diabetes, hypertension, and heart failure. In this direction, symptoms of sleep apnea may comprise snoring and excessive daytime sleepiness. Risk factors include obesity, decreased upper airway dimensions, and heart failure. Thus, one should have a low threshold for sleep testing to assess for sleep apnea. Sleep apnea treatment decreases ventricular arrhythmias and ameliorates some severe bradycardic episodes, often obviating the need for pacemaker implantation. Importantly, comorbidity treatment and lifestyle optimization remain crucial.

Prevalence and predictors of mitral annular disjunction and ventricular ectopy in mitral valve prolapse

BACKGROUND

Mitral annular disjunction (MAD) is associated with ventricular arrhythmia in mitral valve prolapse (MVP). The proportional risk from MAD and other predictors of ventricular arrhythmia in MVP has not been well characterized.

OBJECTIVE

This study aimed to identify predictors of complex or frequent ventricular ectopy (cfVE) in MVP and to quantify risk of cfVE and mortality in MVP with MAD.

METHODS

We studied 632 adult patients with MVP on transthoracic echocardiography at the University of North Carolina Medical Center from 2016 to 2019 (median age, 64 [interquartile range, 52-74] years; 52.7% female; 16.3% African American). Resting and ambulatory electrocardiograms were used to identify cfVE.

RESULTS

MAD was present in 94 (14.9%) patients. Independent associations of MAD were bileaflet prolapse (odds ratio [95% CI], 4.25 [2.47-7.33]; P < .0001), myxomatous valve (2.17 [1.27-3.71]; P = .005), absence of hypertension (2.00 [1.21-3.32]; P = .007), electrocardiogram inferior or lateral lead T-wave inversion (2.07 [1.23-3.48]; P = .006), and female sex (1.99 [1.21-3.25]; P = .006). cfVE was frequent with MAD (39 [41.5%] vs 93 [17.3%] without; P < .0001). Independent cfVE predictors were MAD (hazard ratio [95% CI], 2.23 [1.47-3.36]; P = .0001), bileaflet prolapse (1.86 [1.25-2.76]; P = .002), heart failure (1.79 [1.16-2.77]; P = .009), lower left ventricular ejection fraction (0.14 [0.03-0.61]; P = .009), coronary artery disease (1.60 [1.05-2.43]; P = .03), and inferior or lateral lead T-wave inversion (1.51 [1.03-2.22]; P = .03). After a median of 40 (33-48) months, there was increased mortality with MAD (P = .04).

CONCLUSION

MAD in MVP is associated with bileaflet or myxomatous MVP, absence of hypertension, T-wave inversion, and female sex. There is increased cfVE and mortality with MAD, highlighting the need for closer follow-up of these patients.

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.

Predictive value of cardiac magnetic resonance imaging for fatal arrhythmias in structural and nonstructural heart diseases

Background

The risk stratification for fatal arrhythmias remains inadequate. Cardiac magnetic resonance (CMR) imaging provides a detailed evaluation of arrhythmogenic substrates. This study investigated the predictive capacity of multiparametric CMR for fatal ventricular arrhythmias (VAs) in a heterogeneous disease cohort.

Methods

The study included 396 consecutive patients with structural heart disease (SHD, n = 248) and non-apparent SHD (n = 148) who underwent CMR scans between 2018 and 2022. The primary endpoint was fatal composite arrhythmias.

Results

Thirty-three patients (8.3 %) experienced fatal arrhythmias (25 with SHD, 8 with non-apparent SHD) over a median follow-up of 24 months. The independent risk factors for patients with SHD included syncope (hazard ratio [HR] = 5.347; P < 0.001), VA history (HR = 3.705; P = 0.004), right ventricular ejection fraction (RVEF) ≤ 45 % (HR = 2.587; P = 0.039), and the presence of late gadolinium enhancement (LGE) (HR = 4.767; P = 0.040). In the non-apparent SHD group, fatal arrhythmias were independently correlated with VA history (HR = 10.23; P = 0.005), RVEF ≤ 45 % (HR = 8.307; P = 0.015), and CMR myocardial abnormalities (HR = 5.203; P = 0.033). Patients at high risk of fatal arrhythmia in the SHD and non-apparent SHD groups exhibited 3-year event-free survival rates of 69.4 % and 83.5 %, respectively.

Conclusion

CMR provides effective prognostic information for patients with and without apparent SHD. The presence of LGE, CMR myocardial abnormalities, and right ventricular dysfunction are strong risk markers for fatal arrhythmias.

Atlas of Regional Left Ventricular Scar in Nonischemic Cardiomyopathies: Substrates and Etiologies

Most acquired and inherited cardiomyopathies are characterized by regional left ventricular involvement and nonischemic myocardial scars, often with a disease-specific pattern. Irrespective of the etiology and pathophysiological mechanisms, myocardial disorders are invariably associated with cardiac fibrosis, which contributes to dysfunction and electrical instability. Accordingly, cardiac magnetic resonance plays a central role in the diagnostic work-up and prognostic risk stratification of cardiomyopathies, particularly with the increasing correlation between genetic background and specific disease phenotype. Starting from pattern and distribution of myocardial fibrosis at cardiac magnetic resonance, we provide a practical regional atlas of nonischemic myocardial scar to guide the diagnostic approach to nonischemic cardiomyopathies.

Imaging to Facilitate Ventricular Tachycardia Ablation: Intracardiac Echocardiography, Computed Tomography, Magnetic Resonance, and Positron Emission Tomography

Catheter ablation is a well-established and effective strategy for the management of ventricular tachycardia (VT). However, the identification and characterization of arrhythmogenic substrates for targeted ablation remain challenging. Electrogram abnormalities and responses to pacing during VT provide the classical and most validated methods to identify substrates. However, the 3-dimensional nature of the myocardium, nonconductive tissue, and heterogeneous strands of conductive tissue at the border zones or through the nonconductive zones can prohibit easy electrical sampling and identification of the tissue critical to VT. Intracardiac echocardiography is critical for identification of anatomy, examination of catheter approach and contact, assessment of tissue changes during ablation, and even potential substrates as echogenic regions, but lacks specificity with regard to the latter compared with advanced modalities. In recent decades, cardiac magnetic resonance, computed tomography and positron emission tomography have emerged as valuable tools in the periprocedural evaluation of VT ablation. Cardiac magnetic resonance has unparalleled soft tissue and temporal resolution and excels at identification of expanded interstitial space caused by myocardial infarction, fibrosis, inflammation, or infiltrative myopathies. Computed tomography has excellent spatial resolution and is optimal for identification of anatomic variabilities including wall thickness, thrombus, and lipomatous metaplasia. Positron emission tomography excels at identification of substrates including amyloidosis, sarcoidosis, and other inflammatory substrates. These imaging modalities are vital for assessing arrhythmogenic substrates, guiding optimal access strategy, and assessing ablation efficacy. Although clearly beneficial in specific settings, further clinical trials are needed to enhance generalizability and optimize integration of cardiac imaging for VT ablation.

Brazilian Guideline for Exercise Testing in Children and Adolescents - 2024

CLASSES OF RECOMMENDATION

LEVELS OF EVIDENCE

Floppy Mitral Valve/Mitral Valve Prolapse and Manifestations Not Related to Mitral Regurgitation: Time to Search the Dark Side of the Moon

BACKGROUND

Floppy mitral valve/mitral valve prolapse (FMV/MVP) is a complex entity in which several clinical manifestations are not directly related to the severity of mitral regurgitation (MR).

SUMMARY

Patients with FMV/MVP and trivial to mild MR may have exercise intolerance, orthostatic phenomena, syncope/presyncope, chest pain, and ventricular arrhythmias, among others. Several anatomical and pathophysiologic consequences related to the abnormal mitral valve apparatus and to prolapse of the mitral leaflets into the left atrium provide some explanation for these symptoms. Further, it should be emphasized that MVP is a non-specific finding, while FMV (redundant mitral leaflets, elongated/rupture chordae tendineae, annular dilatation) is the central issue in the MVP story.

KEY MESSAGE

The purpose of this review was to highlight the clinical manifestations of FMV/MVP not directly related to the severity of MR and to discuss the pathophysiologic mechanisms contributing to these manifestations.

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.

Arrhythmic Mitral Valve Prolapse Syndrome and Ventricular Arrhythmias: A Comprehensive Review and the Role of Catheter Ablation

Mitral valve prolapse (MVP) affects 2-3% of the general population, and despite its benign prognosis overall, it is associated with sudden death in a small subset of patients. The term "arrhythmic MVP syndrome" (AMVPS) refers to the presence of frequent or complex ventricular arrhythmias, commonly reported in female patients with a stereotypical phenotype including bileaflet myxomatous disease, ECG repolarisation abnormalities in inferior leads, mitral annular disjunction, and significant fibrosis in the inferolateral LV and papillary muscles. Modern imaging technologies have led to the identification of new risk factors that have been implemented in recent risk stratification guidelines; however, screening for patients with MVP who are at risk of sudden cardiac death (SCD) remains challenging. In addition, there is a limited amount of data on the outcomes of different treatment approaches in AMVP and no specific indication for targeted or disease-modifying therapies within current guidelines. Potential arrhythmic substrates in patients with AMVP syndrome have been the subject of interest in previous studies, with areas consisting of fibrosis at the papillary muscle level and the Purkinje system. Premature ventricular contractions (PVCs) originating from these areas have been shown to play an important role as triggers for ventricular fibrillation and SCD in patients with AMVP. Catheter ablation has emerged as a potential treatment modality in patients with MVP and ventricular arrhythmias (VAs), targeting arrhythmic substrates and triggering PVC foci. The aim of this review is to explore the role of catheter ablation in treating patients with AMVP.

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.

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.