Mitral valve prolapse: arrhythmic risk during pregnancy and postpartum.

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

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

BACKGROUND: Mitral valve prolapse (MVP) is responsible for a considerable disease burden but is widely heterogeneous. The lack of a comprehensive prognostic instrument covering the entire MVP spectrum, encompassing the quantified consequent degenerative mitral regurgitation (DMR), hinders clinical management and therapeutic trials. METHODS: The new Mitral Regurgitation International Database Quantitative (MIDA-Q) registry enrolled 8187 consecutive patients (ages 63±16 years, 47% women, follow-up 5.5±3.3 years) first diagnosed with isolated MVP, without or with DMR quantified prospectively (measuring effective regurgitant orifice [ERO] and regurgitant volume) in routine practice of 5 tertiary care centers from North America, Europe, and the Middle East. The MIDA-Q score ranges from 0 to 15 by accumulating guideline-based risk factors and DMR severity. Long-term survival under medical management was the primary outcome end point. RESULTS: MVP was associated with DMR absent/mild (ERO <20 mm2) in 50%, moderate (ERO 20-40 mm2) in 25%, and severe or higher (ERO ≥40 mm2) in 25%, with mean ERO 24±24 mm2, regurgitant volume 37±35 mL. Median MIDA-Q score was 4 with a wide distribution (10%-90% range, 0-9). MIDA-Q score was higher in patients with EuroScore II ≥1% versus <1% (median, 7 versus 3; P < 0.0001) but with wide overlap (10%-90% range, 4-11 versus 0-7) and mediocre correlation (R2 0.18). Five-year survival under medical management was strongly associated with MIDA-Q score, 97±1% with score 0, 95±1% with score 1 to 2, 82±1% with score 3 to 4, 67±1% with score 5 to 6, 60±1% with score 7 to 8, 44±1% with score 9 to 10, 35±1% with score 11 to 12, and 5±4% with MIDA-Q score ≥13, with hazard ratio 1.31 [1.29-1.33] per 1-point increment. Excess mortality with higher MIDA-Q scores persisted after adjustment for age, sex, and EuroScore II (adjusted hazard ratio, 1.13 [1.11-1.15] per 1-point increment). Subgroup analysis showed persistent association of MIDA-Q score with mortality in all possible subsets, in particular, with EuroScore II<1% (hazard ratio, 1.08 [1.02-1.14]) or ≥1% (hazard ratio, 1.11 [1.08-1.13]) and with no/mild DMR (hazard ratio, 1.14 [1.10-1.19]) or moderate/severe DMR (hazard ratio, 1.13 [1.10-1.16], all per 1-point increment with P<0.0001). Nested-model and bootstrapping analyses demonstrated incremental prognostic power of MIDA-Q score (all P<0.0001). CONCLUSIONS: This large, international cohort of isolated MVP, with prospective DMR quantification in routine practice, demonstrates the wide range of risk factor accumulation and considerable heterogeneity of outcomes after MVP diagnosis. The MIDA-Q score is strongly, independently, and incrementally associated with long-term survival after MVP diagnosis, irrespective of presentation, and is therefore a crucial prognostic instrument for risk stratification, clinical trials, and management of patients diagnosed with all forms of MVP.

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

INTRODUCTION: Mitral valve prolapse (MVP) is a common clinical condition in the general population. A subgroup of patients with MVP may experience ventricular arrhythmias and sudden cardiac death ("arrhythmic mitral valve prolapse" [AMVP]) but how to stratify arrhythmic risk is still unclear. Our meta-analysis aims to identify predictive factors for arrhythmic risk in patients with MVP. METHODS: We systematically searched Medline, Cochrane, Journals@Ovid, Scopus electronic databases for studies published up to December 28, 2022 and comparing AMVP and nonarrhythmic mitral valve prolapse (NAMVP) for what concerns history, electrocardiographic, echocardiographic and cardiac magnetic resonance features. The effect size was estimated using a random-effect model as odds ratio (OR) and mean difference (MD). RESULTS: A total of 10 studies enrolling 1715 patients were included. Late gadolinium enhancement (LGE) (OR: 16.67; p = .005), T-wave inversion (TWI) (OR: 2.63; p < .0001), bileaflet MVP (OR: 1.92; p < .0001) and mitral anulus disjunction (MAD) (OR: 2.60; p < .0001) were more represented among patients with AMVP than in NAMVP. Patients with AMVP were shown to have longer anterior mitral leaflet (AML) (MD: 2.63 mm; p < .0001), posterior mitral leaflet (MD: 2.96 mm; p < .0001), thicker AML (MD: 0.49 mm; p < .0001), longer MAD length (MD: 1.24 mm; p < .0001) and higher amount of LGE (MD: 1.41%; p < .0001) than NAMVP. AMVP showed increased mechanical dispersion (MD: 8.04 ms; 95% confidence interval: 5.13-10.96; p < .0001) compared with NAMVP. CONCLUSIONS: Our meta-analysis proved that LGE, TWI, bileaflet MVP, and MAD are predictive factors for arrhythmic risk in MVP patients.

Insights into malignant mitral valve degenerative disease from a sudden cardiac death cohort highlighting significant measurement differences from normal.

AIMS: Mitral valve prolapse (MVP) is an accepted cause of sudden cardiac death (SCD) in most autopsy series. Diagnosis at autopsy relies upon subjective assessment with no established objective pathological criteria. This study set out to establish objective measurements to help pathologists dealing with SCD. METHODS: We diagnosed 120 (1.5%) cases of MVP in 8108 cases of SCD. We measured the mitral annulus, anterior and posterior leaflets, rough zone and mitral annular disjunction (MAD) in 27 MVP cases and compared them to 54 age- and sex-matched normal mitral valves. RESULTS: Age of death was 39 ± 16 years, with 59 females and 61 males. History of mild MV disease was present in 19 (16%). Eleven (9%) died associated with exertion. Left ventricular hypertrophy was present in nine (15%) females and 10 (16%) males. Both MV leaflets showed thickening and ballooning in all individuals. MVP showed highly significantly increased annular circumference, elongation and thickening of both leaflets as well as increased MAD (all P < 0.001). Left ventricular fibrosis was present in 108 (90%), with interstitial fibrosis in the posterolateral wall and papillary muscle in 88 (81%) and coexisting replacement fibrosis in 40 (37%). CONCLUSION: This is the largest MVP associated with SCD series highlighting a young cohort with equal representation of males and females. There is involvement of both leaflets with significant annular dilatation, elongation and thickening of both leaflets with MAD. Left ventricular fibrosis explains arrhythmia. Our quantitative measurements should serve as a reference for pathologists assessing post-mortem hearts for MVP.

Mitral annular disjunction and mitral valve prolapse extrapolating adult data to an adolescent cohort?

PURPOSE OF REVIEW: The aim of this study is to provide an update on mitral valve prolapse (MVP) and mitral annular disjunction (MAD) and who may be at risk for ventricular arrhythmias and sudden cardiac death. RECENT FINDINGS: MVP is generally considered a benign condition. However, a small subset of patients may be at risk for life-threatening ventricular arrhythmias. Among the risk factors identified in adults include patients with bileaflet mitral valves, myxomatous changes, myocardial fibrosis, and the presence of MAD. Advances in multimodal imaging have allowed for improved identification of fibrosis, anatomical valve derangements, and the amount of MAD. Recent guidelines have suggested that patients with MVP with or without MAD may be at risk for life-threatening arrhythmias if they have had prior ventricular arrhythmias, ventricular dysfunction, or unexplained syncope. Yet, extrapolation of adult data to a pediatric cohort with similar MVP and MAD at this juncture is challenging. There is, however, early evidence that some pediatric patients with significant myocardial fibrosis or abnormal tissue Doppler may be at risk for ventricular tachycardia. SUMMARY: Mitral valve prolapse and mitral annular disjunction at times coexist and at other times can be seen as isolated entities. While the incidence of arrhythmic MVP is quite rare, there is increasing evidence that certain select adults with MVP may be at risk for ventricular tachycardia and sudden cardiac death. Future multicenter studies are needed to better understand the natural history of arrhythmic mitral valve disease and how early disease manifestation in children may impact findings now being reported in young adults.

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

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

Feasibility of concomitant exclusion of left atrial appendage during novel transapical off-pump beating heart mitral valve repair.

The AtriClip device enables the safe and reproducible epicardial clipping of the left atrial appendage. Transapical off-pump beating heart mitral valve repair using NeoChord DS100 Artificial Chordae Delivery System has matured and become more standardized. We aim to evaluate the feasibility of combining NeoChord repair and left atrial appendage exclusion in a single procedure through the same minithoracotomy in patients with mitral valve prolapse and atrial fibrillation. From 2018 to 2019, seven patients with severe mitral regurgitation and atrial fibrillation underwent transesophageal echocardiography-guided transapical off-pump mitral valve repair with the novel NeoChord DS 1000 system and concomitant left atrial appendage exclusion using the AtriClip Pro II device. Both procedures were performed via left mini-thoracotomy. The AtriClip device was applied after the NeoChord repair was done. All seven patients had less than moderate mitral regurgitation after the NeoChord repair and successful left atrial appendage occlusion. There were no device or procedure-related complications. Clinical follow-up revealed significant symptomatic improvement, and no cardiovascular complications were reported. Transesophageal echocardiography at 6-12 months post-procedure showed stable left atrial appendage occlusion with no residual flow between the left atrium and the left atrial appendage and a stump of less than 5 mm. Beating heart epicardial clipping of the left atrial appendage using AtriClip concomitant with transapical mitral valve repair using Neochord DS 1000 system is a feasible and safe treatment option in mitral valve prolapse and atrial fibrillation in patients with limited indications. However, its safety needs to be confirmed in a larger series of patients.

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

PURPOSE OF THE REVIEW: To summarize currently available data on the topic of mitral valve prolapse (MVP) and its correlation to the occurrence of atrial and ventricular arrhythmias. To assess the prognostic value of several diagnostic methods such as transthoracic echocardiography, transesophageal echocardiography, cardiac magnetic resonance, cardiac computed tomography, electrocardiography, and electrophysiology concerning arrhythmic episodes. To explore intra and extracellular biochemistry of the cardiovascular system and its biomarkers as diagnostic tools to predict rhythm disturbances in the MVP population. RECENT FINDINGS: MVP is a common and mainly benign valvular disorder. It affects 2-3% of the general population. MVP is a heterogeneous and highly variable phenomenon with three structural phenotypes: myxomatous degeneration, fibroelastic deficiency, and forme fruste. Exercise intolerance, supraventricular tachycardia, and chest discomfort are the symptoms that are often paired with psychosomatic components. Though MVP is thought to be benign, the association between isolated MVP without mitral regurgitation (MR) or left ventricle dysfunction, with ventricular arrhythmia (VA) and sudden cardiac death (SCD) has been observed. The incidence of SCD in the MVP population is around 0.6% per year, which is 6 times higher than the occurrence of SCD in the general population. Often asymptomatic MVP population poses a challenge to screen for VA and prevent SCD. Therefore, it is crucial to carefully assess the risk of VA and SCD in patients with MVP with the use of various tools such as diagnostic imaging and biochemical and genetic screening.

Arrhythmic mitral valve prolapse and mitral annular disjunction: pathophysiology, risk stratification, and management.

Mitral valve prolapse (MVP) is the most frequent valve condition but remains a conundrum in many aspects, particularly in regard to the existence and frequency of an arrhythmic form (AMVP) and its link to sudden cardiac death. Furthermore, the presence, frequency, and significance of the anatomic functional feature called mitral annular disjunction (MAD) have remained widely disputed. Recent case series and cohorts have shattered the concept that MVP is most generally benign and have emphasized the various phenotypes associated with clinically significant ventricular arrhythmias, including AMVP. The definition, evaluation, follow-up, and management of AMVP represent the focus of the present review, strengthened by recent coherent studies defining an arrhythmic MVP phenotypic that would affect a small subset of patients with MVP at concentrated high risk. The role of MAD in this context is of particular importance, and this review highlights the characteristics of AMVP phenotypes and MAD, their clinical, multimodality imaging, and rhythmic evaluation. These seminal facts lead to proposing a risk stratification clinical pathway with consideration of medical, rhythmologic, and surgical management and have been objects of recent expert consensus statements and of proposals for new research directions.

Myocardial Fibrosis at Cardiac MRI Helps Predict Adverse Clinical Outcome in Patients with Mitral Valve Prolapse.

Background Patients with mitral valve prolapse (MVP) may develop adverse outcomes even in the absence of mitral regurgitation or left ventricular (LV) dysfunction. Purpose To investigate the prognostic value of mitral annulus disjunction (MAD) and myocardial fibrosis at late gadolinium enhancement (LGE) cardiac MRI in patients with MVP without moderate-to-severe mitral regurgitation or LV dysfunction. Materials and Methods In this longitudinal retrospective study, 118 144 cardiac MRI studies were evaluated between October 2007 and June 2020 at 15 European tertiary medical centers. Follow-up was from the date of cardiac MRI examination to June 2020; the minimum and maximum follow-up intervals were 6 months and 156 months, respectively. Patients were excluded if at least one of the following conditions was present: cardiomyopathy, LV ejection fraction less than 40%, ischemic heart disease, congenital heart disease, inflammatory heart disease, moderate or worse mitral regurgitation, participation in competitive sport, or electrocardiogram suggestive of channelopathies. In the remainder, cardiac MRI studies were reanalyzed, and patients were included if they were aged 18 years or older, MVP was diagnosed at cardiac MRI, and clinical information and electrocardiogram monitoring were available within 3 months from cardiac MRI examination. The end point was a composite of adverse outcomes: sustained ventricular tachycardia (VT), sudden cardiac death (SCD), or unexplained syncope. Multivariable Cox regression analysis was performed. Results A total of 474 patients (mean age, 47 years ± 16 [SD]; 244 women) were included. Over a median follow-up of 3.3 years, 18 patients (4%) reached the study end point. LGE presence (hazard ratio, 4.2 [95% CI: 1.5, 11.9]; P = .006) and extent (hazard ratio, 1.2 per 1% increase [95% CI: 1.1, 1.4]; P = .006), but not MAD presence (P = .89), were associated with clinical outcome. LGE presence had incremental prognostic value over MVP severity and sustained VT and aborted SCD at baseline (area under the receiver operating characteristic curve, 0.70 vs 0.62; P = .03). Conclusion In contrast to mitral annulus disjunction, myocardial fibrosis determined according to late gadolinium enhancement at cardiac MRI was associated with adverse outcome in patients with mitral valve prolapse without moderate-to-severe mitral regurgitation or left ventricular dysfunction. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Gerber in this issue.

Effectiveness of the risk stratification proposed by the 2022 European Heart Rhythm Association Expert Consensus statement on arrhythmic mitral valve prolapse.

BACKGROUND: Recently, an expert consensus statement proposed indications where implantation of a primary prevention implantable cardioverter-defibrillator (ICD) may be reasonable in patients with mitral valve prolapse (MVP). The objective was to evaluate the proposed risk stratification by the expert consensus statement. METHODS: Consecutive patients with MVP without alternative arrhythmic substrates with cardiac magnetic resonance imaging (CMR) were included in a single-center retrospective registry. Arrhythmic MVP (AMVP) was defined as a total premature ventricular complex burden ≥5%, non-sustained ventricular tachycardia (VT), VT, or ventricular fibrillation. The end point was a composite of SCD, VT, inducible VT, and appropriate ICD shocks. RESULTS: In total, 169 patients (52.1% male, median age 51.4 years) were included and 99 (58.6%) were classified as AMVP. Multivariate logistic regression identified the presence of late gadolinium enhancement (OR 2.82, 95%CI 1.45-5.50) and mitral annular disjunction (OR 1.98, 95%CI 1.02-3.86) as only predictors of AMVP. According to the EHRA risk stratification, 5 patients with AMVP (5.1%) had a secondary prevention ICD indication, while in 69 patients (69.7%) the implantation of an ICD may be reasonable. During a median follow-up of 8.0 years (IQR 5.0-15.6), the incidence rate for the composite arrhythmic end point was 0.3%/year (95%CI 0.1-0.8). CONCLUSION: More than half of MVP patients referred for CMR met the AMVP diagnostic criteria. Despite low long-term event rates, in 70% of patients with AMVP the implantation of an ICD may be reasonable. Risk stratification of SCD in MVP remains an important knowledge gap and requires urgent investigation.

Long-term outcomes of patients with ventricular arrhythmias and negative programmed ventricular stimulation followed with implantable loop recorders: Impact of delayed-enhancement cardiac magnetic resonance imaging.

BACKGROUND: Programed ventricular stimulation (PVS) is a risk stratification tool in patients at risk for adverse arrhythmia outcomes. Patients with negative PVS may yet be at risk for adverse arrhythmia-related events, particularly in the presence of symptomatic ventricular arrhythmias (VA). OBJECTIVE: To investigate the long-term outcomes of real-world patients with symptomatic VA without indication for device therapy and negative PVS, and to examine the role of cardiac scaring on arrhythmia recurrence. METHODS: Patients with symptomatic VA, and late gadolinium enhancement cardiac magnetic resonance imaging (LGE-CMR), and negative PVS testing were included. All patients underwent placement of implantable cardiac monitors (ICM). Survival analysis was performed to investigate the impact of LGE-CMR findings on survival free from adverse arrhythmic events. RESULTS: Seventy-eight patients were included (age 60 ± 14 years, women n = 36 (46%), ejection fraction 57 ± 9%, cardiomyopathy n = 26 (33%), mitral valve prolapse [MVP] n = 9 (12%), positive LGE-CMR scar n = 49 (62%), history of syncope n = 23 (29%)) including patients with primarily premature ventricular contractions (n = 21) or nonsustained VA (n = 57). Patients were followed for 1.6 ± 1.5 years during which 14 patients (18%) experienced VA requiring treatment (n = 14) or syncope due to bradycardia (n = 2). Four/9 patients (44%) with MVP experienced VA (n = 3) or syncope (n = 1). Baseline characteristics between those with and without adverse events were similar (p > 0.05); however, the presence of cardiac scar on LGE-CMR was independently associated with an increased risk of adverse events (hazard ratio: 5.6 95% confidence interval: [1.2-27], p = 0.03, log-rank p = 0.03). CONCLUSIONS: In a real-world cohort with long-term follow-up, adverse arrhythmic outcomes occurred in 18% of patients with symptomatic VA despite negative PVS, and this risk was significantly greater in patients with positive DE-CMR scar. Long term-monitoring, including the use of ICM, may be appropriate in these patients.

Acute mitral regurgitation with and without acute heart failure.

Acute severe mitral regurgitation (MR) is rare, but often leads to cardiogenic shock, pulmonary edema, or both. Most common causes of acute severe MR are chordae tendineae (CT) rupture, papillary muscle (PM) rupture, and infective endocarditis (IE). Mild to moderate MR is often seen in patients with acute myocardial infarction (AMI). CT rupture in patients with floppy mitral valve/mitral valve prolapse is the most common etiology of acute severe MR today. In IE, native or prosthetic valve damage can occur (leaflet perforation, ring detachment, other), as well as CT or PM rupture. Since the introduction of percutaneous revascularization in AMI, the incidence of PM rupture has substantially declined. In acute severe MR, the hemodynamic effects of the large regurgitant volume into the left atrium (LA) during left ventricular (LV) systole, and in turn back into the LV during diastole, are profound as the LV and LA have not had time to adapt to this additional volume. A rapid, but comprehensive evaluation of the patient with acute severe MR is essential in order to define the underline cause and apply appropriate management. Echocardiography with Doppler provides vital information related to the underlying pathology. Coronary arteriography should be performed in patients with an AMI to define coronary anatomy and need for revascularization. In acute severe MR, medical therapy should be used to stabilize the patient before intervention (surgery, transcatheter); mechanical support is often required. Diagnostic and therapeutic steps should be individualized, and a multi-disciplinary team approach should be utilized.

Additional value of cardiac magnetic resonance feature tracking parameters for the evaluation of the arrhythmic risk in patients with mitral valve prolapse.

OBJECTIVES: The identification of patients with mitral valve prolapse (MVP) presenting high arrhythmic risk remains challenging. Cardiovascular Magnetic Resonance (CMR) feature tracking (FT) may improve risk stratification. We analyzed the role of CMR-FT parameters in relation to the incidence of complex ventricular arrhythmias (cVA) in patients with MVP and mitral annular disjunction (MAD). METHODS: 42 patients with MVP and MAD who underwent 1.5 T CMR were classified as MAD-cVA (n = 23, 55%) in case of cVA diagnosed on a 24-h Holter monitoring and as MAD-noVA in the absence of cVA (n = 19, 45%). MAD length, late gadolinium enhancement (LGE), basal segments myocardial extracellular volume (ECV) and CMR-FT were assessed. RESULTS: LGE was more frequent in the MAD-cVA group in comparison with the MAD-noVA group (78% vs 42%, p = 0.002) while no difference was observed in terms of basal ECV. Global longitudinal strain (GLS) was reduced in MAD-cVA compared to MAD-noVA (- 18.2% ± 4.6% vs - 25.1% ± 3.1%, p = 0.004) as well as global circumferential strain (GCS) at the mid-ventricular level (- 17.5% ± 4.7% vs - 21.6% ± 3.1%, p = 0.041). Univariate analysis identified as predictors of the incidence of cVA: GCS, circumferential strain (CS) in the basal and mid infero-lateral wall, GLS, regional longitudinal strain (LS) in the basal and mid-ventricular inferolateral wall. Reduced GLS [Odd ratio (OR):1.56 (confidence interval (CI) 95%: 1.45-2.47; p < 0.001)] and regional LS in the basal inferolateral wall [OR: 1.62 (CI 95%: 1.22-2.13; p < 0.001)] remained independent prognostic factors in multivariate analysis. CONCLUSION: In patients with MVP and MAD, CMR-FT parameters are correlated with the incidence of cVA and may be of interest in arrhythmic risk stratification.

Lifetime exercise dose and ventricular arrhythmias in patients with mitral valve prolapse.

AIMS: Patients with mitral valve prolapse (MVP) have high risk of life-threatening ventricular arrhythmias (VAs). Data on the impact of exercise on arrhythmic risk in these patients are lacking. We explored whether lifetime exercise dose was associated with severe VA and with established risk factors in patients with MVP. Furthermore, we explored the circumstances at the VA event. METHODS AND RESULTS: In this retrospective cohort study, we included patients with MVP and assessed lifetime exercise dose as metabolic equivalents of task (MET) hours/week. Severe VA was defined as sustained ventricular tachycardia or fibrillation, aborted cardiac arrest, and appropriate shock by a primary preventive implantable cardioverter defibrillator. We included 136 MVP patients (48 years [interquartile range (IQR) 35-59], 61% female), and 17 (13%) had previous severe VA. The lifetime exercise dose did not differ in patients with and without severe VA (17 MET h/week [IQR 9-27] vs. 14 MET h/week [IQR 6-31], P = 0.34). Lifetime exercise dose > 9.6 MET h/week was a borderline significant marker for severe VA (OR 3.38, 95% CI 0.92-12.40, P = 0.07), while not when adjusted for age (OR 2.63, 95% CI 0.66-10.56, P = 0.17). Ventricular arrhythmia events occurred most frequently during wakeful rest (53%), followed by exercise (29%) and sleep (12%). CONCLUSION: We found no clear association between moderate lifetime exercise dose and severe VA in patients with MVP. We cannot exclude an upper threshold for safe levels of exercise. Further studies are needed to explore exercise and risk of severe VA.

Secondary leaflet tethering in patients with severe degenerative mitral regurgitation and its association with the severity of mitral regurgitation.

BACKGROUND: The purpose of the study was to determine the association between vena contracta area (VCA) and secondary leaflet tethering among mitral valve prolapse (MVP) patients, and thus to further identify and characterize an MVP with pathological leaflet tethering (MVPt+) phenotype. METHODS: We prospectively evaluated 94 consecutive MVP patients with significant mitral regurgitation (MR) and 21 healthy controls. MVPt+ group was defined as tenting volume index (TVi) > .7 mL/m2 . The three-dimensional (3D) geometry of mitral valve apparatus and VCA was measured with dedicated quantification software. RESULTS: Of the 94 patients with MVP and significant MR, 31 patients showed a TVi > .7 mL/m2 and entered the MVP with leaflet tethering (MVPt+) group. In stepwise multivariate analysis, only prolapse volume index and TVi were independently associated with 3D VCA. 3D VCA, annular area index, and plasma levels of NT-proBNP were independently correlated with the severity of leaflet tethering. ROC curve revealed that a 3D VCA ≥ .55 cm2 is the optimal cutoff point to predict MVPt+ phenotype. CONCLUSIONS: Secondary leaflet tethering is a significant mechanism behind severe degenerative MR, resulting in an MVPt+ phenotype featuring more advanced morphological and hemodynamical characteristics.

Assessment of the mechanism of mitral valve prolapse in children: An echocardiography study.

BACKGROUND: The high complexity of mitral valve anatomy and function in mitral valve prolapse (MVP) is not yet fully understood. OBJECTIVE: The purpose of this study was to analyze each part of the mitral valve apparatus in children to determine its impact on the presence of MVP and to assess the interaction between the coaptation length (CL) and mitral regurgitation severity. METHODS: We prospectively analyzed transthoracic echocardiograms of 60 patients with MVP (mean age 9.8 ± 3.1 years). We compared these patients with 60 control patients without disease. We determined length of leaflets, chordal length, tenting area, coaptation CL, the intrapapillary muscle distance (IPMD) and relation between CL and severity of mitral regurgitation (MR). RESULTS: For patients with MVP, the posterior mitral leaflet (PML) was significantly enlarged 13.9 ± 4.1 mm versus 10.7 ± 3.5 mm (p < .01), the primary chordal length was significantly decreased 15.4 ± 3.61 mm versus 17.6 ± 3.8 mm (p < .02), and IPMD was significantly greater 18.1 ± 2.7 mm versus 16.6 ± 4.3 mm (p < .03). The difference between CL for both the anterior and posterior mitral leaflets correlated positively with MR (r = .249, p < .05). A greater than 4 mm CL correlated with at least MR (sensitivity 100%, specificity 72%) and greater than 5 mm correlated with at least moderate MR (sensitivity 100%, specificity 60%). CONCLUSION: The majority of pediatric patients with mitral valve prolapse have structural abnormalities that are defined well by echocardiography. In addition to the presence of prolapse and regurgitation, routine assessment of leaflet length, thickness, chordal length and papillary muscle distance is fundamental for patients with MVP.

Pitfalls of mitral regurgitation assessment in the presence of mitral valve prolapse.

Adequate grading of mitral regurgitation (MR) in patients with mitral valve prolapse (MVP) in the presence of mid-late systolic jets can represent a major challenge. In this entity, jets are commonly overestimated by echocardiography. Correct quantification is crucial and highly relevant for the further management and prognosis of these oftentimes young patients. This case points out potential pitfalls and underlines the importance to systematically include qualitative, quantitative, and semi-quantitative parameters into the echocardiographic assessment.

Ventricular fibrillation episodes related to managed ventricular pacing algorithm in a patient with mitral valve prolapse - "Arrhythmic MVP due to MVP".

We report a case of an implant cardiac defibrillator (ICD) patient who an ICD implanted for ventricular fibrillation (VF) related to mitral valve prolapse. He has 2 episodes of VF in his device lives. First episode of VF in year 2016 was initiated after a pause related to the MVP™ algorithm with a critically timed PVC. MVP™ was turned off which prevented further VF episodes. However, MVP™ was turned back on at the device replacement in 2018. A second VF episode developed with similar mechanism in 2021 and MVP™ was subsequently turned off with no further VF recorded. This case highlights the importance of recognizing the mechanism of initiation of tachy-arrhythmia episodes and serves as an important reminder regarding optimization of device settings at the time of replacement.

Association of Pectus Excavatum With Ventricular Remodelling and Mitral Valve Abnormalities in Marfan Syndrome.

Background: Marfan syndrome (MFS) is an inherited connective tissue disorder. Pectus excavatum (PEX) is common in MFS. The purpose was to evaluate the association of PEX with cardiovascular manifestations of MFS, biventricular size and function. Methods: MFS adults undergoing cardiac MRI were retrospectively evaluated. Exclusion criteria were incomplete cardiac MRI, significant artifacts, co-existent ischaemic or congenital heart disease. Haller Index (HI) ≥3.25 classified patients as PEX positive (PEX+) and PEX negative (PEX-). Cardiac MRI analysis included assessment of mitral valve prolapse (MVP), mitral annular disjunction (MAD), biventricular volumetry and aortic dimensions. Results: 212 MFS patients were included, 76 PEX+ and 136 PEX- (HI 8.3 ± 15.2 vs 2.3 ± 0.5, P < .001). PEX+ were younger (33.4 ± 12.0 vs 38.1 ± 14.3 years, P = .02) and similar in sex distribution (55% vs 63% male, P = .26) compared to PEX-. MVP and MAD were more frequent in PEX+ vs PEX- (43/76 [57%] vs 37/136 [27%], P < .001; 44/76 [58%] vs 50/136[37%], P = .003, respectively). PEX+ had higher right ventricular end-diastolic and end-systolic volumes (RVEDVi 92 ± 17mL/m2 vs 84 ± 22mL/m2, P = .04; RVESVi 44 ± 10 mL/m2 vs 39 ± 14 mL/m2, P = .02), lower RV ejection fraction (RVEF 52 ± 5% vs 55 ± 6%, P = .01) compared to PEX-. Left ventricular (LV) volumes, LVEF and aortic dimensions were similar. Conclusion: MFS adults with PEX have higher frequency of cardiac manifestations including MV abnormalities, increased RV volumes and lower RVEF compared to those without PEX. Awareness of this association is important for all radiologists who interpret aortic CT or MRI, where HI can be easily measured. PEX in MFS may suggest more severe disease expression necessitating careful screening for MV abnormalities and outcomes surveillance.