Catheter ablation of papillary muscle arrhythmias: Implications of mitral valve prolapse and systolic dysfunction

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.

Arrhythmic Mitral Valve Prolapse and Sports Activity: Pathophysiology, Risk Stratification, and Sports Eligibility Assessment

Although mitral valve prolapse (MVP) is the most prevalent valvular abnormality in Western countries and generally carries a good prognosis, a small subset of patients is exposed to a significant risk of malignant ventricular arrhythmias (VAs) and sudden cardiac death (SCD), the so-called arrhythmic MVP (AMVP) syndrome. Recent work has emphasized phenotypical risk features of severe AMVP and clarified its pathophysiology. However, the appropriate assessment and risk stratification of patients with suspected AMVP remains a clinical conundrum, with the possibility of both overestimating and underestimating the risk of malignant VAs, with the inappropriate use of advanced imaging and invasive electrophysiology study on one hand, and the catastrophic occurrence of SCD on the other. Furthermore, the sports eligibility assessment of athletes with AMVP remains ill defined, especially in the grey zone of intermediate arrhythmic risk. The definition, epidemiology, pathophysiology, risk stratification, and treatment of AMVP are covered in the present review. Considering recent guidelines and expert consensus statements, we propose a comprehensive pathway to facilitate appropriate counseling concerning the practice of competitive/leisure-time sports, envisioning shared decision making and the multidisciplinary "sports heart team" evaluation of borderline cases. Our final aim is to encourage an active lifestyle without compromising patients' safety.

Arrhythmic Mitral Valve Prolapse: Risk Assessment and Management

Arrhythmic mitral valve prolapse (MVP) has gained great interest recently because of the increasing recognition of its potential role in unexplained cardiac arrest. Although evidence has accumulated to show the association of arrhythmic MVP (AMVP) with sudden cardiac death (SCD), risk stratification and management remain unclear. Physicians are faced with the challenges of screening for AMVP among MVP patients and the dilemma of when and how to intervene to prevent SCD in these patients. In addition, there is little guidance to help approach MVP patients who present with an otherwise unexplained cardiac arrest to know whether MVP was the primary cause of cardiac arrest or just an innocent bystander. Herein we review the epidemiology and definition of AMVP, the risk and mechanisms of SCD, and summarize the clinical evidence behind risk markers of SCD and therapeutic interventions that could potentially prevent it. We also propose an algorithm that provides guidance as to how to screen for AMVP and what therapeutic interventions to use. Last, we propose a diagnostic algorithm for approaching patients with otherwise unexplained cardiac arrest who are shown to have MVP.

Arrhythmogenic Mitral Valve Prolapse and Sudden Cardiac Death: An Update and Current Perspectives

Mitral valve prolapse (MVP) affects about 2% to 3% of the general population, mostly women, and is the most common cause of primary chronic mitral regurgitation (MR) in western countries. The natural history is heterogeneous and widely determined by the severity of MR. Although most patients remain asymptomatic with a near-normal life expectancy, approximately 5% to 10 % progress to severe MR. As largely recognized, left ventricular (LV) dysfunction due to chronic volume overload per se identifies a subgroup at risk of cardiac death. However, there is rising evidence of a link between MVP and life threating ventricular arrhythmias (VAs)/sudden cardiac death (SCD) in a small subset of middle-aged patients without significant MR, heart failure and remodeled hearts. The present review focuses on the underlying mechanism of electric instability and unexpected cardiac death in this subset of young patients, from the myocardial scarring of the LV infero-lateral wall due to mechanical stretch exerted by the prolapsing leaflets and mitral annular disjunction, to the inflammation's impact on fibrosis pathways along with a constitutional hyperadrenergic state. The heterogeneity of clinical course reveals a necessity of risk stratification, preferably through noninvasive multimodality imaging, that will help to identify and prevent adverse scenarios in young MVP patients.

Arrhythmic mitral valve prolapse in 2023: Evidence-based update

Patients with mitral valve prolapse (MVP) may develop ventricular arrhythmias, ranging from premature ventricular contractions through more complex non-sustained ventricular tachycardia to sustained life-threatening ventricular arrhythmias. The prevalence of MVP in autopsy series of young adults who died suddenly has been estimated to be between 4% and 7%. Thus, "arrhythmic MVP" has been reported as an underappreciated cause of sudden cardiac death, leading to a renewed interest in the study of this association. The term "arrhythmic MVP" refers to a small subset of patients who have, in the absence of any other arrhythmic substrate, MVP, with or without mitral annular disjunction, and frequent or complex ventricular arrhythmias. Our understanding of their coexistence in terms of contemporary management and prognosis is still incomplete. While literature regarding the arrhythmic MVP may be contrasting despite recent consensus document, the present review summarizes the relevant evidence concerning the diagnostic approach, prognostic implications, and targeted therapies for MVP-related ventricular arrhythmias. We also summarize recent data supporting left ventricular remodeling, which complicates the coexistence of MVP with ventricular arrhythmias. As the evidence for a putative link between MVP-associated ventricular arrhythmias and sudden cardiac death is scarce and based on scant and retrospective data, risk prediction remains a challenge. Thus, we aimed at listing potential risk factors from available seminal reports for further use in a more reliable prediction model that requires additional prospective data. Finally, we summarize evidence and guidelines on targeted therapies of ventricular arrhythmias in the setting of MVP, including implantable cardioverter defibrillators and catheter ablation. Our review highlights current knowledge gaps and provides an action plan for structured research on the pathophysiological genesis, diagnosis, prognostic impact, and optimal management of patients with arrhythmic MVP.

Characterization of ventricular arrhythmias and sudden cardiac death in subjects with mitral valve prolapse and mitral annular disjunction

Sudden cardiac death is reported as the leading cause of mortality in developed nations. Arrhythmic mitral valve disease, encompassing mitral valve prolapse and/or mitral annular disjunction, is thought to be responsible in a sizable portion of these deaths. Despite this evidence, there are no reliable methods or clinically useful risk stratification schemes to determine which group of patients are at higher risk or may benefit from interventions such as catheter ablation or prophylactic implantation of a defibrillator. The reasons for this lack of guidance include our incomplete understanding of the mechanisms of ventricular arrhythmias and the fact that mitral valve prolapse and disjunction are frequently diagnosed, yet carry an overall low risk of sudden cardiac death. This heterogeneity makes the development of a reliable prediction model based on the presence of common risk factors very difficult. In this review, we summarize the relevant literature regarding the epidemiology, diagnosis, pathophysiology, and management of mitral valve prolapse and mitral annular disjunction and elucidate their role in sudden cardiac death.

Needle-Tipped Catheter Ablation of Papillary Muscle Results in Deeper and Larger Ablation Lesions

Ventricular tachycardia associated with papillary muscle (PM) is often refractory to standard radiofrequency ablation (RFA). The needle-tipped ablation catheter (NT-AC) has been used to treat deep intramyocardial substrates, but its use for PM has not been characterized. Using an ex vivo experimental platform, both 3 mm and 6 mm NT-AC created larger ablation lesion volumes and depths than open-irrigated ablation catheter did (OI-AC; e.g., 57.12 ± 9.70mm³ and 2.42 ± 0.22 mm, respectively; p < 0.01 for all comparisons). Longer NT-AC extension (6 mm) resulted in greater ablation lesion volumes and maximum depths (e.g., 333.14 ± 29.13mm³ and 6.46 ± 0.29 mm, respectively, compared to the shorter 3 mm NT-AC extension, 143.33 ± 12.77mm³, and 4.46 ± 0.14 mm; both p < 0.001). There were no steam pops. In conclusion, for PM ablation, the NT-AC was able to achieve ablation lesions that were larger and deeper than with conventional OI-AC. Ablation of PM may be another application for needle-tip ablation. Further studies are warranted to establish long-term safety and efficacy in human studies.

Substrate Characterization and Outcomes of Catheter Ablation of Ventricular Arrhythmias in Patients With Mitral Annular Disjunction

BACKGROUND

Mitral annular disjunction (MAD) has recently been recognized as an arrhythmogenic entity. Data on the electrophysiological substrate as well as the outcomes of catheter ablation of ventricular arrhythmias in patients with MAD is limited.

METHODS

Forty patients with MAD (mean age 47±15 years; 70% female) underwent catheter ablation for ventricular arrhythmias. Detailed clinical, electrocardiographic, cardiac imaging, and procedural data were collected. Clinical outcomes were compared between patients who had substrate modification in the MAD area and those who did not.

RESULTS

Twenty-three (57.5%) patients had ablation for premature ventricular contractions, 10 (25%) patients for sustained ventricular tachycardia, and 7 (17.5%) patients for premature ventricular contraction-triggered ventricular fibrillation ablation. Mean end-systolic MAD length was 10.58±3.49 mm on transthoracic echocardiography. Seventeen (42.5%) patients had preprocedural cardiac magnetic resonance imaging, and 5 (29%) patients had late gadolinium enhancement. Among the 18 (45%) patients who had abnormal local electrograms (low voltage, long-duration, fractionated, isolated mid-diastolic potentials) during electroanatomical mapping, 10 (25%) patients had abnormal electrograms in the anterolateral mitral annulus or MAD area. Substrate modification was performed in 10 (25%) patients. Catheter ablation was acutely successful in 36 (90%) patients (elimination of premature ventricular contraction or noninducibility of ventricular tachycardia). After a median follow-up duration of 54.08 (interquartile range, 10.67-89.79) months, premature ventricular contraction burden decreased from a median of 9.75% (interquartile range, 3.25-14) before the ablation to a median of 4% (interquartile range, 1-7.75) after the ablation (P=0.03 [95% CI, 0.055-6.5]). Eight (20.5%) patients had repeat ablation for ventricular arrhythmias. Substrate modification of the MAD was associated with a trend toward lower rates of repeat ablation (0% versus 26.7%; P=0.16).

CONCLUSIONS

Patients with MAD have a complex arrhythmogenic substrate, and catheter ablation is effective in reducing recurrence of ventricular arrhythmias. Substrate mapping and ablation may be considered in these patients.

Cryoablation of Papillary Muscles at Surgery for Malignant Ventricular Arrhythmias Due to Mitral Valve Prolapse

BACKGROUND

Mitral Valve Prolapse (MVP) is relatively common condition and while generally benign a small subset of patient suffers from malignant ventricular arrhythmias (MVA) and sudden cardiac death (SCD).

METHOD AND MATERIAL

We report three cases of mitral valve prolapse, mitral regurgitation and malignant ventricular arrhythmias refractory to medical therapy, who had surgical cryoablation at the time of surgery on the mitral valve.

RESULTS

During a follow up period ranging from three to eleven years all three patients have remained free of ventricular arrhythmias and cryoablation lesions targeting the base of the papillary muscles have not caused any detrimental effect on the valve function.

CONCLUSION

Surgical cryoablation of papillary muscles as described in this article should be considered in MVP who suffer from MVA, aborted SCD or frequent ventricular ectopics likely to cause LV dysfunction.

Left Ventricular Remodeling in Non-syndromic Mitral Valve Prolapse: Volume Overload or Concomitant Cardiomyopathy?

Mitral valve prolapse (MVP) is a common valvular disorder that can be associated with mitral regurgitation (MR), heart failure, ventricular arrhythmias and sudden cardiac death. Given the prognostic impact of these conditions, it is important to evaluate not only mitral valve morphology and regurgitation, but also the presence of left ventricular (LV) function and remodeling. To date, several possible hypotheses have been proposed regarding the underlying mechanisms of LV remodeling in the context of non-syndromic MVP, but the exact pathophysiological explanation remains elusive. Overall, volume overload related to severe MR is considered the main cause of LV dilatation in MVP. However, significant LV remodeling has been observed in patients with MVP and no/mild MR, particularly in patients with bileaflet MVP or Barlow's disease, generating several new hypotheses. Recently, the concept of "prolapse volume" was introduced, adding a significant volume load to the LV on top of the transvalvular MR volume. Another possible hypothesis is the existence of a concomitant cardiomyopathy, supported by the link between MVP and myocardial fibrosis. The origin of this cardiomyopathy could be either genetic, a second hit (e.g., on top of genetic predisposition) and/or frequent ventricular ectopic beats. This review provides an overview of the different mechanisms and remaining questions regarding LV remodeling in non-syndromic MVP. Since technical specifications of imaging modalities impact the evaluation of MR severity and LV remodeling, and therefore might influence clinical decision making in these patients, this review will also discuss assessment of MVP using different imaging modalities.

Malignant Mitral Valve Prolapse: Risk and Prevention of Sudden Cardiac Death

Purpose of review

The purpose of this review is to explore the prevalence and risk factors for a malignant phenotype in mitral valve prolapse (MVP) characterized by life-threatening ventricular arrhythmias and sudden cardiac arrest and death (SCD), including mechanistic and pathophysiologic findings and mechanism-based potential therapies.

Recent findings

A malignant phenotype in MVP characterized by life-threatening arrhythmias has long been recognized, although MVP is often benign. Efforts to identify this malignant phenotype have revealed potential risk factors for SCD that include elongated, myxomatous leaflets, ECG changes and complex ventricular ectopy. More recently, malignant MVP has been associated with myocardial fibrosis in the papillary muscles and inferobasal left ventricular wall. This localization suggests a central role of prolapse-induced mechanical forces on the myocardium in creating an arrhythmogenic substrate and triggering life-threatening arrhythmias. This mechanism for fibrosis is also consistent with imaging evidence of prolapse-induced mechanical changes in the papillary muscles and inferobasal left ventricular wall. Currently, no therapy to prevent SCD in malignant MVP has been established and limited clinical data are available. Mechanistic information and prospective study have the potential to identify patients at risk of SCD and preventive strategies.

Summary

Malignant MVP relates to unique properties and mechanical abnormalities in the mitral valve apparatus and adjacent myocardium. Increased understanding of disease mechanisms and determinants of arrhythmias is needed to establish effective therapies.

Developing a Mechanistic Approach to Sudden Death Prevention in Mitral Valve Prolapse

Sudden cardiac death (SCD) from ventricular fibrillation (VF) can occur in mitral valve prolapse (MVP) in the absence of other comorbidities including mitral regurgitation, heart failure or coronary disease. Although only a small proportion with MVP are at risk, it can affect young, otherwise healthy adults, most commonly premenopausal women, often as the first presentation of MVP. In this review, we discuss arrhythmic mechanisms in MVP and mechanistic approaches for sudden death risk assessment and prevention. We define arrhythmogenic or arrhythmic MVP (AMVP) as MVP associated with complex and frequent ventricular ectopy, and malignant MVP (MMVP) as MVP with high risk of SCD. Factors predisposing to AMVP are myxomatous, bileaflet MVP and mitral annular disjunction (MAD). Data from autopsy, cardiac imaging and electrophysiological studies suggest that ectopy in AMVP is due to inflammation, fibrosis and scarring within the left ventricular (LV) base, LV papillary muscles and Purkinje tissue. Postulated mechanisms include repetitive injury to these regions from systolic papillary muscle stretch and abrupt mitral annular dysmotility (excursion and curling) and diastolic endocardial interaction of redundant mitral leaflets and chordae. Whereas AMVP is seen relatively commonly (up to 30%) in those with MVP, MVP-related SCD is rare (2-4%). However, the proportion at risk (i.e., with MMVP) is unknown. The clustering of cardiac morphological and electrophysiological characteristics similar to AMVP in otherwise idiopathic SCD suggests that MMVP arises when specific arrhythmia modulators allow for VF initiation and perpetuation through action potential prolongation, repolarization heterogeneity and Purkinje triggering. Adequately powered prospective studies are needed to assess strategies for identifying MMVP and the primary prevention of SCD, including ICD implantation, sympathetic modulation and early surgical mitral valve repair. Given the low event rate, a collaborative multicenter approach is essential.

Arrhythmic Mitral Valve Prolapse and Mitral Annular Disjunction: Clinical Features, Pathophysiology, Risk Stratification, and Management

Mitral valve prolapse (MVP) is a common cause of valvular heart disease. Although many patients with MVP have a benign course, there is increasing recognition of an arrhythmic phenotype associated with ventricular arrhythmias and sudden cardiac death (SCD). Pathophysiologic mechanisms associated with arrhythmias include cardiac fibrosis, mechanical stress induced changes in ventricular refractory periods, as well as electrophysiologic changes in Purkinje fibers. Clinically, a variety of risk factors including demographic, electrocardiographic, and imaging characteristics help to identify patients with MVP at the highest at risk of SCD and arrhythmias. Once identified, recent advances in treatment including device therapy, catheter ablation, and surgical interventions show promising outcomes. In this review, we will summarize the incidence of ventricular arrhythmias and SCD in patients with MVP, the association with mitral annular disjunction, mechanisms of arrhythmogenesis, methods for arrhythmic and SCD risk stratification including findings with multimodality imaging, and treatments for the primary and secondary prevention of SCD.

Arrhythmias in Patients With Valvular Heart Disease: Gaps in Knowledge and the Way Forward

The prevalence of both organic valvular heart disease (VHD) and cardiac arrhythmias is high in the general population, and their coexistence is common. Both VHD and arrhythmias in the elderly lead to an elevated risk of hospitalization and use of health services. However, the relationships of the two conditions is not fully understood and our understanding of their coexistence in terms of contemporary management and prognosis is still limited. VHD-induced left ventricular dysfunction/hypertrophy and left atrial dilation lead to both atrial and ventricular arrhythmias. On the other hand, arrhythmias can be considered as an independent condition resulting from a coexisting ischemic or non-ischemic substrate or idiopathic ectopy. Both atrial and ventricular VHD-induced arrhythmias may contribute to clinical worsening and be a turning point in the natural history of VHD. Symptoms developed in patients with VHD are not specific and may be attributable to hemodynamical consequences of valve disease but also to other cardiac conditions including arrhythmias which are notably prevalent in this population. The issue how to distinguish symptoms related to VHD from those related to atrial fibrillation (AF) during decision making process remains challenging. Moreover, AF is a traditional limit of echocardiography and an important source of errors in assessment of the severity of VHD. Despite recent progress in understanding the pathophysiology and prognosis of postoperative AF, many questions remain regarding its prevention and management. Furthermore, life-threatening ventricular arrhythmias can predispose patients with VHD to sudden cardiac death. Evidence for a putative link between arrhythmias and outcome in VHD is growing but available data on targeted therapies for VHD-related arrhythmias, including monitoring and catheter ablation, is scarce. Despite growing evidences, more research focused on the prognosis and optimal management of VHD-related arrhythmias is still required. We aimed to review the current evidence and identify gaps in knowledge about the prevalence, prognostic considerations, and treatment of atrial and ventricular arrhythmias in common subtypes of organic VHD.

ORIGINAL ARTICLESCatheter Ablation For Papillary Muscle Arrhythmias A Systematic Review

Background

Catheter ablation of papillary muscle ventricular arrhythmias (PM‐VAs) has been associated with unsatisfactory results. Features that may affect acute and long‐term procedural outcomes are not well established.

Objective

To systematically review the available data in the literature assessing efficacy and safety of PM‐VAs catheter ablation.

Methods

An online search of PubMed, Cochrane Registry, Web of Science, Scopus and EMBASE libraries (from inception to March 1, 2021) was performed, in addition to manual screening. Twenty‐one observational noncontrolled case‐series were considered eligible for the systematic review, including 536 patients.

Results

Postero‐medial PM harbored 60.8% of PM‐VAs, while antero‐lateral PM and right ventricular PMs 34.9% and 4.3% of cases, respectively. The mean acute success rate of the index ablation procedure was 88.1% (95% CI 82.8% to 91.9%, p < .001, I² 0%). After a mean follow‐up period of 15.5 ± 17.4 months, pooled long‐term arrhythmia‐free rate was 69.2%, while the pooled long‐term success rate after multiple ablation procedure was 84.9%. Overall, procedure complications occurred in nine patients (1.7%) and no procedure‐related deaths were reported. The use of intracardiac echocardiography (ICE) as well as contact force sensing (CFS) and irrigated catheters during ablation was associated with higher rates of arrhythmia‐freedom at long‐term follow‐up.

Conclusions

Catheter ablation is an effective and safe strategy for PM‐VAs, with an acute success rate of 88.1%, a long‐term success rate of 69.2%, with a relatively low procedural complication rate. The use of ICE, irrigated catheters and catheters with CFS capability was associated with higher rates of arrhythmia‐freedom at long‐term follow‐up.

The Outcome of Ventricular Arrhythmias Associated With Mitral Valve Prolapse After Catheter Ablation: A Systematic Review and Meta-Analysis

The presence of mitral valve prolapse (MVP) varies from asymptomatic to life-threatening arrhythmias. Catheter ablation (CA) is widely used to treat ventricular arrhythmias (VAs) associated with MVP. Despite having high procedural success, outcome data after CA is limited, especially in a long-term setting. Therefore, this systematic review and meta-analysis were performed. Literature searching was conducted in Pubmed, EuropePMC, Proquest, and Ebsco from inception to December 2020 using keywords: ventricular arrhythmia, premature ventricular complex, ventricular tachycardia, ventricular fibrillation, mitral valve prolapse, and catheter ablation. A total of 407 potential articles were retrieved for further review. The final review resulted in six articles for systematic review and meta-analysis. The study was registered in PROSPERO (CRD42020219144). The most common origin of VAs was papillary muscle. The acute success rate of CA in the MVP group varies between 66% and 94%. Follow-up studies reported a higher percentage of VAs recurrence after CA in the MVP group (22.22%) compared with the non-MVP group (11.38%). However, the difference is not significant (P-value = 0.16). Other studies reported a 12.5%-36% rate and 40% of repeat ablation in the medium term and the long term, respectively. Episodes of sudden cardiac death during exertion could still occur following CA in patients with MVP. Distinct origin of VAs was observed during repeated ablation procedures, which may explain arrhythmic substrate progression. Diffuse left ventricular fibrosis around papillary muscle rather than local fibrosis was observed among older patients. Furthermore, the presence of mitral annular disjunction (MAD) and Filamin C mutation might increase the risk of recurrent VAs. CAn has been done as the treatment of VAs associated with MVP. The acute success rate of CA varies between studies and the number of patients requiring repeat CA varied from 12.5% to 40%. Sudden cardiac death could still occur after CA. Older age during CA, genetic predisposition, deep arrhythmic foci, multifocal VAs origin, diffuse fibrosis, and the presence of MAD may contribute to the recurrence of VAs. Further studies, stratification, and evaluation are needed to prevent fatal outcomes in VA associated with MVP, even after CA.

Arrhythmic mitral valve prolapse: Diagnostic parameters for high-risk patients: A systematic review and meta-analysis

BACKGROUND

Although frequently considered a benign condition, new evidence has shown that mitral valve prolapse (MVP) is associated with complex ventricular arrhythmias (VAs) and sudden cardiac death (SCD). Therefore, we conducted a systematic review and meta-analysis of the relevant studies to investigate the parameters that could identify MVP patients at higher risk of experiencing complex VAs.

METHOD

We performed a systematic literature search of PubMed for potential studies between January 2010 and January 2021. Our meta-analysis included studies comparing MVP patients with complex VAs (A-MVP) and those without (NA-MVP). We used the fixed-effects model to obtain the odds ratio (OR), risk ratio (RR), or mean difference (MD) and 95% confidence interval (CI) for each analyzed parameter.

RESULTS

Six studies with 848 individuals were included in the meta-analysis. As compared to the NA-MVP patients, A-MVP patients had a higher prevalence of inverted T-wave (OR: 2.73; 95% CI: 1.85-4.02; p < .00001) and longer QTc interval on the resting ECG (MD: 14.73; 95% CI: 9.39-20.08; p < .00001), longer anterior mitral leaflet length (MD: 2.67; 95% CI: 2.02-3.31; p < .00001), bi-leaflet prolapse (OR: 1.65; 95% CI: 1.22-2.24; p = .001), and mitral annulus disjunction (MAD) on echocardiogram (RR: 1.90; 95% CI: 1.50-2.40; p < .00001), and late gadolinium enhancement (LGE) on cardiac magnetic resonance (RR: 4.38; 95% CI: 1.77-10.86; p = .001).

CONCLUSION

Our comprehensive meta-analysis suggests that risk factors related to A-MVP are T-wave inversion, longer QTc interval, bi-leaflet prolapse, longer anterior mitral valve leaflet, MAD, and LGE.

Left ventricular remodelling in mitral valve prolapse patients: implications of apical papillary muscle insertion

AIMS

Mitral valve prolapse (MVP) causes left ventricular (LV) remodelling even in the absence of significant mitral regurgitation. To evaluate whether apical insertion of the papillary muscle (PM) influences the pattern and severity of MVP-related LV remodelling.

METHODS AND RESULTS

All MVP patients who underwent CMR at our institution between December 2008 and December 2019 were included, thoroughly reviewed and grouped according to apical/non-apical PM insertion. Apical PM insertion was found in 53/92 patients (58%) and associated with mitral leaflet thickening (P < 0.01) and a trend towards higher prevalence of mitral annular disjunction (P = 0.05). Whereas no differences in ventricular volumes or ejection fraction were found, patients with apical PM insertion showed more lateral wall remodelling with mid lateral wall thinning [2.1 (1.8-2.5) vs. 4.0 (3.5-5.0) mm, P < 0.01], increased LV eccentricity and a lower GCS at this level (15 ± 3% vs. 20 ± 3%, P < 0.01). In long-axis direction, increased end-diastolic mid lateral wall angulation was found (i.e. angle <155° measured in the thinnest point of the mid lateral wall in four-chamber view) with a higher angle variation during systole (25 ± 11° vs. 17 ± 8°, P < 0.01). Remarkably, PM fibrosis was significantly more frequent in patients with apical PM insertion (i.e. 66% vs. 28%, P < 0.01). Finally, a higher burden of premature ventricular complexes (>5%) and non-sustained ventricular tachyarrhythmias was found in patients with apical PM insertion: 53% vs. 25% (P = 0.04) and 38% vs. 18% (P = 0.04), respectively.

CONCLUSION

Apical PM insertion is part of the phenotypic spectrum of MVP, impacts significantly LV remodelling, and potentially may be related to increased ventricular arrhythmogenicity.

Mitral Valve Prolapse and Its Motley Crew-Syndromic Prevalence, Pathophysiology, and Progression of a Common Heart Condition

Mitral valve prolapse (MVP) is a commonly occurring heart condition defined by enlargement and superior displacement of the mitral valve leaflet(s) during systole. Although commonly seen as a standalone disorder, MVP has also been described in case reports and small studies of patients with various genetic syndromes. In this review, we analyzed the prevalence of MVP within syndromes where an association to MVP has previously been reported. We further discussed the shared biological pathways that cause MVP in these syndromes, as well as how MVP in turn causes a diverse array of cardiac and noncardiac complications. We found 105 studies that identified patients with mitral valve anomalies within 18 different genetic, developmental, and connective tissue diseases. We show that some disorders previously believed to have an increased prevalence of MVP, including osteogenesis imperfecta, fragile X syndrome, Down syndrome, and Pseudoxanthoma elasticum, have few to no studies that use up-to-date diagnostic criteria for the disease and therefore may be overestimating the prevalence of MVP within the syndrome. Additionally, we highlight that in contrast to early studies describing MVP as a benign entity, the clinical course experienced by patients can be heterogeneous and may cause significant cardiovascular morbidity and mortality. Currently only surgical correction of MVP is curative, but it is reserved for severe cases in which irreversible complications of MVP may already be established; therefore, a review of clinical guidelines to allow for earlier surgical intervention may be warranted to lower cardiovascular risk in patients with MVP.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: executive summary

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

The effect of catheter ablation for ventricular arrhythmias originating from the left ventricular papillary muscles on mitral valve function

BACKGROUND

Ablation of ventricular arrhythmias (VA) originating from the left ventricular (LV) papillary muscles (PM) has the potential to damage the mitral valve apparatus resulting in mitral regurgitation (MR). This study sought to evaluate the effect of radiofrequency (RF) ablation of a PM on MR severity.

METHODS

Patients with pre- and postablation transthoracic echocardiograms who underwent PM ablation for treatment of VA were retrospectively identified and compared to similar patients who underwent VA ablation at non-PM sites. MR severity was evaluated pre- and postablation in both groups and graded as none/trace (Grade 0); mild/mild-to-moderate (Grade 1); moderate (Grade 2); moderate-to-severe/severe (Grade 3).

RESULTS

A total of 45 and 49 patients were included in the PM and non-PM groups, respectively. There were no significant baseline demographic differences. The PM group had longer RF ablation times (22.3 vs. 13.3 min, p < .01) compared to the non-PM group. Most patients had low-grade MR in both groups at baseline. Change in pre- versus postablation MR within the PM group was not statistically significant by Wilcoxon rank-sum test (Figure 2, p = .46). MR severity following ablation was also evaluated using logistic regression models. The odds ratio for worsening MR in the PM group compared to non-PM was 0.19 (95% confidence interval: 0.008-4.18, p = .29) after adjusting for comorbidities, LV ejection fraction, and LV internal end-diastolic diameter.

CONCLUSION

RF ablation of VA originating from PM under intracardiac echocardiography guidance did not result in clinically or statistically significant worsening of MR.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: Executive summary

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Parameters associated with ventricular arrhythmias in mitral valve prolapse with significant regurgitation

OBJECTIVE

Mitral valve prolapse (MVP) has been associated with ventricular arrhythmias (VA), but little is known about VA in patients with significant primary mitral regurgitation (MR). Our aim was to describe the prevalence of symptomatic VA in patients with MVP (fibro-elastic deficiency or Barlow's disease) referred for mitral valve (MV) surgery because of moderate-to-severe MR, and to identify clinical, electrocardiographic, standard and advanced echocardiographic parameters associated with VA.

METHODS

610 consecutive patients (64±12 years, 36% female) were included. Symptomatic VA was defined as symptomatic and frequent premature ventricular contractions (PVC, Lown grade ≥2), non-sustained or sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) without ischaemic aetiology.

RESULTS

A total of 67 (11%) patients showed symptomatic VA, of which 3 (4%) had VF, 3 (4%) sustained VT, 27 (40%) non-sustained VT and 34 (51%) frequent PVCs. Patients with VA were significantly younger, more often female and showed T-wave inversions; furthermore, they showed significant MV morphofunctional abnormalities, such as mitral annular disjunction (39% vs 20%, p<0.001), and dilatation (annular diameter 37±5 mm vs 33±6 mm, p<0.001), lower global longitudinal strain (GLS 20.9±3.1% vs 22.0±3.6%, p=0.032) and prolonged mechanical dispersion (45±12 ms vs 38±14 ms, p=0.003) as compared with patients without VA. Female sex, increased MV annular diameter, lower GLS and prolonged mechanical dispersion were identified as independent associates of symptomatic VA.

CONCLUSION

In patients with MVP with moderate-to-severe MR, symptomatic VA are relatively frequent and associated with significant MV annular abnormalities, subtle left ventricular function impairment and heterogeneous contraction. Assessment of these parameters might help decision-making over further diagnostic analyses and improve risk-stratification.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Long-term outcomes of ablation for ventricular arrhythmias in mitral valve prolapse

PURPOSE

Prior studies reporting efficacy of radiofrequency catheter ablation for complex ventricular ectopy in mitral valve prolapse (MVP) are limited by selective inclusion of bileaflet MVP, papillary muscle only ablation, or short-term follow-up. We sought to evaluate the long-term incidence of hemodynamically significant ventricular tachycardia (VT) or fibrillation (VF) in patients with MVP after initial ablation.

METHODS

We studied consecutive patients with MVP undergoing ablation for complex ventricular ectopy between 2013 and 2017 at our institution. Of 580 patients with MVP, we included 15 (2.6%, 10 women; mean age 50 ± 14 years, 53% bileaflet) with complex ventricular ectopy treated with initial ablation.

RESULTS

Over a median follow-up of 3406 (1875-6551) days or 9 years, 5 of 15 (33%) patients developed hemodynamically significant VT/VF after their initial ablation and underwent placement of an implantable cardioverter defibrillator (ICD). Three of 5 also underwent repeat ablations. Sustained VT was inducible prior to index ablation in all 5 who developed VT/VF, compared to none of the 10 patients who did not develop VT/VF after index ablation (p = 0.002). Complex ventricular ectopy at index ablation was multifocal in all 5 patients who underwent repeat intervention versus 4 of 10 patients (40%) who did not (p = 0.04). All 3 patients with subsequent VT/VF who underwent repeat ablation had a new clinically dominant focus of ventricular arrhythmia and 3 of the patients with ICD had appropriate VT/VF therapies.

CONCLUSIONS

In the long term, a subset of MVP patients treated with ablation for ventricular arrhythmias, all with multifocal ectopy on initial EP study, develop hemodynamically significant VT/VF. Our findings suggest the progressive nature of ventricular arrhythmias in patients with MVP and multifocal ectopy.

Electrophysiological Substrates in Papillary Muscle Arrhythmias – Implications for Catheter Ablation

Collapse

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias: Executive summary

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

Papillary muscle ventricular arrhythmias in patients with arrhythmic mitral valve prolapse: Electrophysiologic substrate and catheter ablation outcomes

BACKGROUND

Mitral valve prolapse (MVP) is a common valve condition and has been associated with sudden cardiac death. Premature ventricular contractions (PVCs) from the papillary muscles (PMs) may play a role as triggers for ventricular fibrillation (VF) in these patients.

OBJECTIVES

To characterize the electrophysiological substrate and outcomes of catheter ablation in patients with MVP and PM PVCs.

METHODS

Of 597 patients undergoing ablation of ventricular arrhythmias during the period 2012-2015, we identified 25 patients with MVP and PVCs mapped to the PMs (64% female). PVC-triggered VF was the presentation in 4 patients and a fifth patient died suddenly during follow-up. The left ventricle ejection fraction (LVEF) was 50.5% ± 11.8% and PVC burden was 24.4% ± 13.1%. A cardiac magnetic resonance imaging was performed in nine cases and areas of late gadolinium enhancement were found in four of them. A detailed LV voltage map was performed in 11 patients, three of which exhibited bipolar voltage abnormalities. Complete PVC elimination was achieved in 19 (76%) patients and a significant reduction in PVC burden was observed in two (8%). In patients in which the ablation was successful, the PVC burden decreased from 20.4% ± 10.8% to 6.3% ± 9.5% (P = 0.001). In 5/6 patients with depressed LVEF and successful ablation, the LV function improved postablation. No significant differences were identified between patients with and without VF.

CONCLUSIONS

PM PVCs are a source of VF in patients with MVP and can induce PVC-mediated cardiomyopathy that reverses after PVC suppression. Catheter ablation is highly successful with more than 80% PVC elimination or burden reduction.