Causes and mechanisms of isolated mitral regurgitation in the community: clinical context and outcome

Mitral Regurgitation Evaluation in Modern Echocardiography: Bridging Standard Techniques and Advanced Tools for Enhanced Assessment

Mitral regurgitation (MR) is one of the most common valvular heart diseases worldwide. Echocardiography remains the first line and most effective imaging modality for the diagnosis of mitral valve (MV) pathology and quantitative assessment of MR. The advent of three-dimensional echocardiography has significantly enhanced the evaluation of MV anatomy and function. Furthermore, recent advancements in cardiovascular imaging software have emerged as step-forward tools, providing a powerful support for acquisition, analysis, and interpretation of cardiac ultrasound images in the context of MR. This review aims to provide an overview of the contemporary workflow for echocardiographic assessment of MR, encompassing standard echocardiographic techniques and the integration of semiautomated and automated ultrasound solutions. These novel approaches include advancements in segmentation, phenotyping, morphological quantification, functional grading, and chamber quantification.

Transcatheter Approaches to Atrial Functional Mitral Regurgitation: How Far Have We Come?

Functional mitral regurgitation (MR) is associated with increased cardiovascular morbidity and mortality and over the past decade, the diagnosis of atrial functional mitral regurgitation (aFMR) has been increasingly observed in the elderly, especially in those with atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF). Annular enlargement, perturbations of annular contraction, and atriogenic leaflet tethering distinguish the pathophysiology of aFMR from the one of ventricular origin. However, no consensus provides recommendations regarding the differential diagnosis and the subsequent management of aFMR. The advent of transcatheter mitral valve repair has paved the way for various treatments including edge-to-edge repair (TEER), mitral annuloplasty, and replacement, with optimistic results on short-medium-term outcome provided by preliminary studies. In parallel, rhythm control of AF for paroxysmal and persistent types, should be pursued to induce reverse remodeling and restoring the normal leaflet coaptation. In this setting, catheter ablation aiming for electrical isolation of the pulmonary veins is the most widely recognized and effective strategy for maintaining sinus rhythm. Nevertheless, arrhythmia-free survival is lower in patients with persistent and long-term persistent AF, leading to the adoption of hybrid strategies combining transcatheter endocardial ablation and thoracoscopic epicardial surgical ablation. This review provides an update on the diagnosis and treatment of aFMR, focusing on available transcatheter approaches that can be performed in the catheterization lab and electrophysiology lab.

Global, Regional, and National Burden of Valvular Heart Disease, 1990 to 2021

BACKGROUND

Valvular heart disease poses an escalating global health challenge with an increasing impact on mortality and disability. This study aims to comprehensively analyze the global burden of valvular heart disease.

METHODS AND RESULTS

Using the Global Burden of Disease 2021 data, we analyzed the prevalence and disability-adjusted life years, examining implications across demographics and geographic regions. In 2021, an estimated 54.8 million (95% uncertainty interval [UI], 43.3-67.6) cases of rheumatic heart disease, 13.3 million (95% UI, 11.4-15.2) cases of nonrheumatic calcific aortic valve disease (CAVD), and 15.5 million (95% UI, 14.5-16.7) cases of nonrheumatic degenerative mitral valve disease (DMVD) were reported globally. Despite the rising prevalence, disability-adjusted life years declined between 1991 and 2021. Among individuals aged 70 years or older, the age-standardized prevalences were 1803.6 per 100 000 (95% UI, 1535.5-2055.7) for CAVD and 2148.9 per 100 000 (95% UI, 2001.4-2310.1) for DMVD. Sub-Saharan Africa had the highest age-standardized prevalence for rheumatic heart disease; Conversely, high-income regions led in CAVD and DMVD prevalence. Rheumatic heart disease had the highest age-standardized prevalence of 1184.2 per 100 000 (95% UI, 932.4-1478.2) in low Socio-Demographic Index (SDI) regions, whereas CAVD peaked at 349.8 per 100 000 (95% UI, 303.6-395.8) in high SDI regions. The most substantial increases in age-standardized prevalences of CAVD from 1990 to 2021 occurred in the middle SDI and low-middle SDI regions. A parallel trend was noted for DMVD.

CONCLUSIONS

Rheumatic heart disease remains a significant burden in low SDI regions, whereas CAVD and DMVD pose challenges in high SDI regions with aging populations.

Clinical and echocardiographic parameters associated with outcomes in patients with moderate secondary mitral regurgitation

BACKGROUND

Significant secondary mitral regurgitation (SMR) is known to be associated with worse prognosis. However, data focusing specifically on moderate SMR and associated risk factors are lacking. In the present study, clinical and echocardiographic parameters associated with outcomes were evaluated in a large cohort of patients with moderate SMR.

METHODS

Patients with moderate SMR were retrospectively included and stratified by New York Heart Association (NYHA) class and specific aetiology (atrial SMR (aSMR) or ventricular SMR (vSMR)) with a further classification of vSMR based on left ventricular ejection fraction (LVEF) ≥40% or <40%. The primary endpoint was all-cause mortality and the secondary endpoint was the composite of all-cause mortality and heart failure (HF) events.

RESULTS

Of the total 1061 patients with moderate SMR (age 69±11 years, 59% male) included, 854 (80%) were in NYHA class I-II and 207 (20%) were in NYHA class III-IV. Regarding the aetiology, 352 (33%) had aSMR and 709 (67%) had vSMR, of which 329 (46%) had LVEF ≥40% and 380 (54%) had LVEF <40%. During a median follow-up of 82 (IQR 55-115) months, 397 (37%) died and 539 (51%) patients had HF events or died. On multivariable analysis, NYHA class III-IV (HR 1.578; 95% CI 1.244 to 2.002, p<0.001) and SMR aetiology were independently associated with both endpoints. Specifically, compared to aSMR, vSMR with LVEF ≥40% had a HR of 1.528 (95% CI 1.108 to 2.106, p=0.010) and vSMR with LVEF <40% had a HR of 1.960 (95% CI 1.434 to 2.679, p<0.001). To further support these findings, patients were matched for (1) NYHA class and (2) SMR aetiology by propensity scores including age, sex, diabetes, chronic obstructive pulmonary disease, renal function, left atrial volume index, NYHA class (only for SMR aetiology matching), LVEF, SMR aetiology (only for NYHA class matching), tricuspid regurgitation severity and right ventricular pulmonary artery coupling index. After matching, NYHA class and SMR aetiology remained associated with both outcomes (for both: log rank p<0.050).

CONCLUSION

In patients with moderate SMR, distinction in SMR aetiology and assessment of symptoms are important independent determinants of outcome.

Atrial and ventricular functional mitral regurgitation: prevalence, characteristics, outcomes, and disease progression

AIMS

Limited data exist on the natural history of functional mitral regurgitation (FMR), including atrial (AFMR), ventricular (VFMR), and dual FMR. This study examined the prevalence, characteristics, outcomes, and progression of these FMR subtypes.

METHODS AND RESULTS

Consecutive patients with ≥mild to moderate FMR were included and classified as AFMR, VFMR, or dual FMR. AFMR is characterized by left atrial enlargement, while VFMR involves left ventricular enlargement or reduced left ventricular ejection fraction. Dual FMR combines features of both. Clinical outcome was all-cause mortality and heart failure (HF) hospitalization. Echocardiographic outcome was the progression from mild-moderate/moderate to severe FMR and from AFMR/VFMR to dual FMR. Of 22 814 patients, AFMR, VFMR, and dual FMR were identified in 39%, 14%, and 47%, respectively. Most (84%) had mild-moderate to moderate FMR. Over a median clinical follow-up of 4.7 years, dual FMR has the highest risk of all-cause mortality and HF hospitalization. Compared with AFMR, patients with VFMR have a higher incidence of all-cause mortality (adjusted HR = 1.73, 95%CI 1.54-1.94, P < 0.001) and HF hospitalization (adjusted HR = 1.23, 95%CI 1.15-1.32, P < 0.001). In the serial cohort with 2.4 (1.0-4.9) years echocardiogram follow-up, VFMR was associated with a 1.51-fold and 3.08-fold increase in the risk of progressing to severe FMR and dual FMR than AFMR (both P < 0.001). Sensitivity analyses did not change these findings.

CONCLUSION

AFMR and VFMR have significant differences in survival and disease progression. Dual FMR is a common and distinct disease process that occurs in the progression of AFMR or VFMR and is associated with a poor prognosis.

[Atrial fibrillation in combination with severe mitral regurgitation : Which should be treated first, the atrial fibrillation or the mitral valve?]

BACKGROUND

The primary therapeutic approach for severe secondary mitral regurgitation (MR) in combination with atrial fibrillation is often not clear.

OBJECTIVES/METHODS

To create a therapeutic guideline for daily clinical practice based on a case report as well as basic literature.

RESULTS

If a functional component is suspected, restoration of sinus rhythm may lead to a significant improvement in MR. The extent of the improvement and the time required to achieve this improvement are often difficult to predict.

CONCLUSIONS

The involvement of an electrophysiologist is recommended in order to assess the likelihood of successful long-term rhythm control aimed at improving MR. In unclear cases, cardioversion combined with short-term administration of antiarrhythmic medication may be useful to demonstrate potential improvement of MR in sinus rhythm.

Risks factors of adverse clinical outcomes in asymptomatic mitral regurgitation patients with preserved ejection fraction: a systematic review and meta-analysis

INTRODUCTION AND OBJECTIVE

Indication for mitral valve (MV) surgery in asymptomatic mitral regurgitation (MR) patients with preserved ejection fraction (EF) remains unclear. This study aims to identify risk factors of adverse clinical outcomes in asymptomatic MR patients with preserved EF for early indication of MV surgery.

METHODS

3 databases were systematically searched to include studies with asymptomatic MR patients with preserved EF. Risk factors of adverse clinical outcomes (composite outcome of MACE and MV surgery indication), mortality, and left ventricular dysfunction (LVD) are pooled with a meta-analysis of random effect model.

RESULTS

A total of 39 observational studies with 9135 asymptomatic moderate to severe MR patients are included. We identified 21 statistically significant risk factors for adverse outcomes. Increased natriuretic peptide, presence of atrial fibrillation, LV GLS > 20%, LVEDD > 35 mm, LVESD > 22 mm, and LAVI > 55 ml/mm2, ERO > 55mm2, and regurgitation volume > 60 ml (HR 2.21, 2.07, 4.23, 2.98, 4.05, 1.84, 4.02, 3.30, respectively; p-value < 0.05; I2 0-87%) are associated with greater risk of adverse clinical outcome. Risk factors associated with postoperative LVD are the increase of LVEDD, LVESD, and RVSP. Risk factors associated with mortality are increasing STS score and LV GLS.

CONCLUSION

Several clinical parameters and risk factors can be used to stratify asymptomatic MR patients with preserved ejection fraction who could benefit from early indication for MV surgery.

Impact of transcatheter edge to edge repair in functional mitral regurgitation and cardiac resynchronization-therapy nonresponders

BACKGROUND

Despite optimal medical therapy and cardiac resynchronization therapy (CRT), significant functional mitral regurgitation (MR) persisted in 30% of the patients and labeled as CRT nonresponders.

AIMS

We sought to study the impact of transcatheter edge-to-edge repair (TEER) in patients with symptomatic grade III and IV functional MR despite CRT.

METHODS

A retrospective analysis was conducted of all patients who had prior CRT for at least 6 months and underwent TEER for significant residual functional MR (grade ≥3) and symptomatic heart failure (HF) at our institution. The primary outcomes were the change in New York Heart Association classification (NYHA), MR grade, echo parameters, and NT-ProBNP from baseline to 1-year post-procedure.

RESULTS

A total of 28 patients were identified, mean age of 73 ± 6.7 years and 89% males. Procedure success was achieved in all patients. At 1-year follow-up, patients had lower MR grade (median 2, IQR 1 [1,2] vs. 4, IQR 1 [3,4]; p < 0.001), NYHA class (median 2, IQR 1 [2,3] vs. 3, IQR 1 [3,4]; p < 0.001), and NT-ProBNP (7658 ± 11322 vs. 3760 ± 4431; p = 0.035) compared to before the TEER procedure. The left ventricular end-diastolic volume (255 ± 59 vs. 244 ± 66 mm; p = 0.016) and the right ventricular systolic pressure (52 ± 14 mmHg vs. 37 ± 13 mmHg, <0.001) decreased.

CONCLUSION

Patients who remain symptomatic after CRT with severe functional MR had improved functional status and MR grade at 1-year following TEER. There was a signal toward reverse remodeling.

Reappraisal of the Concept and Implications of Pulmonary Hypertension in Degenerative Mitral Regurgitation

BACKGROUND

European and U.S. clinical guidelines diverge regarding pulmonary hypertension (PHTN) in degenerative mitral regurgitation (DMR). Gaps in knowledge underpinning these divergences affect risk assessment and management recommendations attached to systolic pulmonary pressure (SPAP) in DMR.

OBJECTIVES

This study sought to define PHTN links to DMR severity, prognostic thresholds, and independent outcome impact in a large quantitative DMR registry.

METHODS

This study gathered a large multicentric registry of consecutive patients with isolated moderate-to-severe DMR, with DMR and SPAP quantified prospectively at diagnosis.

RESULTS

In 3,712 patients (age 67 ± 15 years, 36% women) with ≥ moderate-to-severe DMR, effective regurgitant orifice (ERO) was 0.42 ± 0.19 cm2, regurgitant volume 66 ± 327 mL/beat and SPAP 41 ± 16 mm Hg. Spline-curve analysis showed excess mortality under medical management emerging around SPAP 35 mm Hg and doubling around SPAP 50 mm Hg. Accordingly, severe pulmonary hypertension (sPHTN) (SPAP ≥50 mm Hg) was detected in 916 patients, moderate pulmonary hypertension (mPHTN) (SPAP 35-49 mm Hg) in 1,128, and no-PHTN (SPAP <35 mm Hg) in 1,668. Whereas SPAP was strongly associated with DMR-ERO, nevertheless excess mortality with sPHTN (adjusted HR: 1.65; 95% CI: 1.24-2.20) and mPHTN (adjusted HR: 1.44; 95% CI: 1.11-1.85; both P ≤ 0.005) was observed independently of ERO and all baseline characteristics and in all patient subsets. Nested models demonstrated incremental prognostic value of mPHTN and sPHTN (all P < 0.0001). Despite higher operative risk with mPHTN and sPHTN, DMR surgical correction was followed by higher survival in all PHTN ranges with strong survival benefit of early surgery (<3 months). Postoperatively, excess mortality was abolished (P ≥ 0.30) in mPHTN, but only abated in sPHTN.

CONCLUSIONS

This large international registry, with prospectively quantified DMR and SPAP, demonstrates a Doppler-defined PHTN impact on mortality, independent of DMR severity. Crucially, it defines objectively the new and frequent mPHTN range, independently linked to excess mortality under medical management, which is abolished by DMR correction. Thus, at DMR diagnosis, Doppler-SPAP measurement defining these new PHTN ranges, is crucial to guiding DMR management.

Characterisation of global and regional mitral annular strains in an acute porcine model

OBJECTIVES

This study aimed to explore regional mitral annular strain using a novel computational method.

METHODS

Eight pigs underwent implantation with piezoelectric transducers around the mitral annulus. Interventions of pre- and afterload were performed by inferior vena cava constriction and endovascular balloon occlusion of the descending aorta. The mitral annulus was reconstructed in a mathematical model and divided into 6 segments. Global and segmental annular strain were calculated from a discrete mathematical representation.

RESULTS

Global annular strain gradually decreased after isovolumetric contraction until late systole. Mitral annular end-systolic strain demonstrated shortening in all segments except the anterior segment, which showed the least deformation. The P2 annular segment demonstrated the most end-systolic shortening (-7.6 ± 1.1% at baseline, P < 0.001 compared to anterior segment). Systolic global annular strain showed no significant change in response to load interventions but correlated positively with left ventricular contractility at baseline and after preload reduction.

CONCLUSIONS

Mitral annular systolic strain demonstrates cyclical variations with considerable regional heterogeneity, with the most pronounced deformation in posterior annular segments. Measurements appear independent of changes to pre- and afterload.

Atrial cardiomyopathy revisited-evolution of a concept: a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS)

AIMS

The concept of "atrial cardiomyopathy" (AtCM) had been percolating through the literature since its first mention in 1972. Since then, publications using the term were sporadic until the decision was made to convene an expert working group with representation from four multinational arrhythmia organizations to prepare a consensus document on atrial cardiomyopathy in 2016 (EHRA/HRS/APHRS/SOLAECE expert consensus on atrial cardiomyopathies: definition, characterization, and clinical implication). Subsequently, publications on AtCM have increased progressively.

METHODS AND RESULTS

The present consensus document elaborates the 2016 AtCM document further to implement a simple AtCM staging system (AtCM stages 1-3) by integrating biomarkers, atrial geometry, and electrophysiological changes. However, the proposed AtCM staging needs clinical validation. Importantly, it is clearly stated that the presence of AtCM might serve as a substrate for the development of atrial fibrillation (AF) and AF may accelerates AtCM substantially, but AtCM per se needs to be viewed as a separate entity.

CONCLUSION

Thus, the present document serves as a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS) to contribute to the evolution of the AtCM concept.

Atrial Functional Mitral Regurgitation: From Diagnosis to Current Interventional Therapies

Mitral regurgitation (MR) is one of the most common valvular pathologies worldwide, contributing to the morbidity and mortality of several cardiovascular pathologies, including heart failure (HF). Novel transcatheter treatment for MR has given the opportunity for a safe and feasible alternative, to surgery, in order to repair the valve and improve patient outcomes. However, after the results of early transcatheter edge-to-edge repair (TEER) trials, it has become evident that subcategorizing the mitral regurgitation etiology and the left ventricular function, in patients due to undergo TEER, is of the essence, in order to predict responsiveness to treatment and select the most appropriate patient phenotype. Thus, a novel MR phenotype, atrial functional MR (AFMR), has been recently recognized as a distinct pathophysiological entity, where the etiology of the regurgitation is secondary to annular dilatation, in a diseased left atrium, with preserved left ventricular function. Recent studies have evaluated and compared the outcomes of TEER in AFMR with ventricular functional MR (VFMR), with the results favoring the AFMR. In specific, TEER in this patient substrate has better echocardiographic and long-term outcomes. Thus, our review will provide a comprehensive pathogenesis and mechanistic overview of AFMR, insights into the echocardiographic approach of such patients and pre-procedural planning, discuss the most recent clinical trials and their implications for future treatment directions, as well as highlight future frontiers of research in the setting of TEER and transcatheter mitral valve replacement (TMVR) in AFMR patients.

Atrial Functional Mitral Regurgitation Subtypes Undergoing Transcatheter Edge-to-Edge Repair: Suboptimal Outcomes in Atriogenic Hamstringing

BACKGROUND

Two subtypes of atrial functional mitral regurgitation (AFMR) have been described, one is characterized by Carpentier type I and the other by Carpentier type IIIb leaflet motion.

OBJECTIVES

The authors sought to analyze echocardiographic characteristics and outcomes of AFMR subtypes undergoing mitral valve transcatheter edge-to-edge repair (M-TEER).

METHODS

Of 1,047 consecutive patients who underwent M-TEER, the authors identified those with isolated mitral annulus dilation (Carpentier I), termed AFMR-IAD, and those with atriogenic hamstringing characterized by restricted posterior mitral leaflet motion (Carpentier IIIb), termed AFMR-AH. Echocardiographic baseline characteristics and outcomes up to 1-year were analyzed.

RESULTS

A total of 128 patients (12.2%) met AFMR criteria; 75 (58.6%) were identified as AFMR-IAD and 53 (41.4%) as AFMR-AH. AFMR-AH displayed greater left atrial and left ventricular volumes, greater mitral annulus, shorter and steeper posterior mitral leaflet, and more pronounced MR (all P < 0.05). Technical success was achieved in 98.7% (AFMR-IAD) and 86.8% (AFMR-AH) of patients (P = 0.009). At discharge, device detachments were exclusively observed in AFMR-AH (10.0%). MR ≤II was achieved in 95.6% and 78.6% at 30 days (P = 0.009) and in 93.0% and 74.1% at 1 year (P = 0.038) in patients with AFMR-IAD and AFMR-AH, respectively. AFMR-AH was associated with procedural failure (OR: 1.17 [95% CI: 1.00-1.38]; P = 0.045) at 30 days (43.4% vs 24.0%; P = 0.023) and all-cause mortality (HR: 2.54 [95% CI: 1.09-5.91]; P = 0.031) at 1 year (77% vs 92%, Kaplan-Meier estimated 1-year survival; P = 0.017).

CONCLUSIONS

AFMR-AH shows worse procedural and clinical outcomes following M-TEER than AFMR-IAD. Thus, vigilance regarding this pathology is warranted and alternative mitral valve therapies might need to be considered.

Management of secondary mitral regurgitation: from drugs to devices

Severe secondary mitral regurgitation carries a poor prognosis with one in five patients dying within 12 months of diagnosis. Fortunately, there are now a number of safe and effective therapies available to improve outcomes. Here, we summarise the most up-to-date treatments. Optimal guideline-directed medical therapy is the mainstay therapy and has been shown to reduce the severity of mitral regurgitation in 40-45% of patients. Rapid medication titration protocols reduce heart failure hospitalisation and facilitate earlier referral for device therapy. The pursuit of sinus rhythm in patients with atrial fibrillation has been shown to significantly reduce mitral regurgitation severity, as has the use of cardiac resynchronisation devices in patients who meet guideline-directed criteria. Finally, we highlight the key role of mitral valve intervention, particularly transcatheter edge-to-edge repair (TEER) for management of moderate-severe mitral regurgitation in carefully selected patients with poor left ventricular systolic function, with a number needed to treat of 3.1 to reduce heart failure hospitalisation and 5.9 to reduce all-cause death. To slow the rapid accumulation of morbidity and mortality, we advocate a proactive approach with accelerated medical optimisation, followed by management of atrial fibrillation and cardiac resynchronisation therapy if indicated, then, rapid referral to the Heart Team for consideration of mitral valve intervention in patients with ongoing symptoms and at least moderate-severe mitral regurgitation. Mitral TEER has been shown to be 'reasonably cost-effective' (but not cost-saving) in the UK in selected patients, although TEER remains underused with only 6.5 procedures per million population (pmp) compared with Germany (77 pmp), Switzerland (44 pmp) and the USA (32 pmp).

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.

Lifelong cardiovascular care in Turner syndrome: two cases with review of literature

Cardiovascular disease is one of the most important complications in girls and women with Turner syndrome (TS). Although the latest international guideline provides useful suggestions for the management of cardiovascular diseases in TS, some unknown cardiac conditions warrant physicians' attention and awareness. Here, we have reported two adult cases wherein significant cardiovascular diseases were detected during the transition period. The first case patient was diagnosed with aortic crank deformity and left subclavian artery aneurysm at 14 years based on the report of cardiac catheterization, computed tomography angiography, and cardiac magnetic resonance imaging, which had remained undetected by annual evaluations using transthoracic echocardiography (TTE). This case emphasizes the importance of cardiac reevaluation during the transition period. The second case patient was diagnosed with moderate mitral valve regurgitation (MR) due to mitral valve prolapse at 18 years through TTE, although the first evaluation at 7 years by TTE detected slight MR without any clinical concerns. The condition however progressed to severe MR at 28 years, requiring mitral valvuloplasty. MR is the most common valve disease worldwide, which makes it challenging to comprehend whether the condition is a complication. However, the condition requiring surgery at this age is extremely rare, which implies the possibility of early progression. Because almost all literature on cardiovascular complications in TS is cross-sectional, further information about longitudinal cardiovascular conditions is vital for optimal care for girls and women with TS. The two cases reported in this article provide significant information for improving lifelong cardiovascular health issues in TS.

Outcomes of maze procedure and mitral valve surgery in atrial functional mitral regurgitation: a retrospective study

BACKGROUND

Atrial functional mitral regurgitation (AFMR) is a newly discovered condition associated with longstanding atrial fibrillation. This retrospective study aimed to analyze the outcomes of the maze procedure and mitral regurgitation (MR) surgery in AFMR and atrial fibrillation in comparison with those in degenerative MR (DMR).

METHODS

Patients who underwent mitral valve repair/replacement with a maze procedure at a hospital (July 2012-August 2021) were included. We excluded patients aged below 18 years undergoing concomitant coronary artery bypass grafting or atrial septal defect repair and those with MR etiology other than ARMR or DMR.

RESULTS

We included 35 patients with AFMR and 50 patients with DMR. Patient characteristics and postoperative outcomes were not significantly different between the two groups. Long-term outcomes revealed no significant differences in the ratio of cardiac mortality, stroke, or hospital readmission. However, after the maze procedure, the sinus rhythm restoration rate was significantly lower (62% vs. 28.5%, p < 0.001), a junctional rhythm state (p < 0.001) and permanent pacemaker insertion for sick sinus syndrome (SSS) (p = 0.03) were significantly more common in AFMR than DMR. On postoperative transthoracic echocardiography (TTE), the pulmonary artery systolic pressure was significantly less decreased in the AFMR group than in the DMR group compared with that on preoperative TTE (p = 0.04).

CONCLUSIONS

AFMR showed excellent mitral valve surgery outcomes, similar to DMR, but had a significantly higher risk of pacemaker insertion for SSS after the maze procedure.

Degenerative mitral regurgitation due to flail leaflet: sex-related differences in presentation, management, and outcomes

BACKGROUND AND AIMS

Presentation, outcome, and management of females with degenerative mitral regurgitation (DMR) are undefined. We analysed sex-specific baseline clinical and echocardiographic characteristics at referral for DMR due to flail leaflets and subsequent management and outcomes.

METHODS

In the Mitral Regurgitation International Database (MIDA) international registry, females were compared with males regarding presentation at referral, management, and outcome (survival/heart failure), under medical treatment, post-operatively, and encompassing all follow-up.

RESULTS

At referral, females (n = 650) vs. males (n = 1660) were older with more severe symptoms and higher MIDA score. Smaller cavity diameters belied higher cardiac dimension indexed to body surface area. Under conservative management, excess mortality vs. expected was observed in males [standardized mortality ratio (SMR) 1.45 (1.27-1.65), P < .001] but was higher in females [SMR 2.00 (1.67-2.38), P < .001]. Female sex was independently associated with mortality [adjusted hazard ratio (HR) 1.29 (1.04-1.61), P = .02], cardiovascular mortality [adjusted HR 1.58 (1.14-2.18), P = .007], and heart failure [adjusted HR 1.36 (1.02-1.81), P = .04] under medical management. Females vs. males were less offered surgical correction (72% vs. 80%, P < .001); however, surgical outcome, adjusted for more severe presentation in females, was similar (P ≥ .09). Ultimately, overall outcome throughout follow-up was worse in females who displayed persistent excess mortality vs. expected [SMR 1.31 (1.16-1.47), P < .001], whereas males enjoyed normal life expectancy restoration [SMR 0.92 (0.85-0.99), P = .036].

CONCLUSIONS

Females with severe DMR were referred to tertiary centers at a more advanced stage, incurred higher mortality and morbidity under conservative management, and were offered surgery less and later after referral. Ultimately, these sex-related differences yielded persistent excess mortality despite surgery in females with DMR, while males enjoyed restoration of life expectancy, warranting imperative re-evaluation of sex-specific DMR management.

Wearable device-measured moderate to vigorous physical activity and risk of degenerative aortic valve stenosis

BACKGROUND AND AIMS

Physical activity has proven effective in preventing atherosclerotic cardiovascular disease, but its role in preventing degenerative valvular heart disease (VHD) remains uncertain. This study aimed to explore the dose-response association between moderate to vigorous physical activity (MVPA) volume and the risk of degenerative VHD among middle-aged adults.

METHODS

A full week of accelerometer-derived MVPA data from 87 248 UK Biobank participants (median age 63.3, female: 56.9%) between 2013 and 2015 were used for primary analysis. Questionnaire-derived MVPA data from 361 681 UK Biobank participants (median age 57.7, female: 52.7%) between 2006 and 2010 were used for secondary analysis. The primary outcome was the diagnosis of incident degenerative VHD, including aortic valve stenosis (AS), aortic valve regurgitation (AR), and mitral valve regurgitation (MR). The secondary outcome was VHD-related intervention or mortality.

RESULTS

In the accelerometer-derived MVPA cohort, 555 incident AS, 201 incident AR, and 655 incident MR occurred during a median follow-up of 8.11 years. Increased MVPA volume showed a steady decline in AS risk and subsequent AS-related intervention or mortality risk, levelling off beyond approximately 300 min/week. In contrast, its association with AR or MR incidence was less apparent. The adjusted rates of AS incidence (95% confidence interval) across MVPA quartiles (Q1-Q4) were 11.60 (10.20, 13.20), 7.82 (6.63, 9.23), 5.74 (4.67, 7.08), and 5.91 (4.73, 7.39) per 10 000 person-years. The corresponding adjusted rates of AS-related intervention or mortality were 4.37 (3.52, 5.43), 2.81 (2.13, 3.71), 1.93 (1.36, 2.75), and 2.14 (1.50, 3.06) per 10 000 person-years, respectively. Aortic valve stenosis risk reduction was also observed with questionnaire-based MVPA data [adjusted absolute difference Q4 vs. Q1: AS incidence, -1.41 (-.67, -2.14) per 10 000 person-years; AS-related intervention or mortality, -.38 (-.04, -.88) per 10 000 person-years]. The beneficial association remained consistent in high-risk populations for AS, including patients with hypertension, obesity, dyslipidaemia, and chronic kidney disease.

CONCLUSIONS

Higher MVPA volume was associated with a lower risk of developing AS and subsequent AS-related intervention or mortality. Future research needs to validate these findings in diverse populations with longer durations and repeated periods of activity monitoring.

Mitral Annular Disease at Cardiac MRI: What to Know and Look For

Accurate evaluation of the mitral valve (MV) apparatus is essential for understanding the mechanisms of MV disease across various clinical scenarios. The mitral annulus (MA) is a complex and crucial structure that supports MV function; however, conventional imaging techniques have limitations in fully capturing the entirety of the MA. Moreover, recognizing annular changes might aid in identifying patients who may benefit from advanced cardiac imaging and interventions. Multimodality cardiovascular imaging plays a major role in the diagnosis, prognosis, and management of MV disease. Transthoracic echocardiography is the first-line modality for evaluation of the MA, but it has limitations. Cardiac MRI (CMR) has emerged as a robust imaging modality for assessing annular changes, with distinct advantages over other imaging techniques, including accurate flow and volumetric quantification and assessment of variations in the measurements and shape of the MA during the cardiac cycle. Mitral annular disjunction (MAD) is defined as atrial displacement of the hinge point of the MV annulus away from the ventricular myocardium, a condition that is now more frequently diagnosed and studied owing to recent technical advances in cardiac imaging. However, several unresolved issues regarding MAD, such as the functional significance of pathologic disjunction and how this disjunction advances in the clinical course, require further investigation. The authors review the role of CMR in the assessment of MA disease, with a focus on MAD and its functional implications in MV prolapse and mitral regurgitation. ©RSNA, 2024 Supplemental material is available for this article. See the invited commentary by Stojanovska and Fujikura in this issue.

Surgical outcome of mitral valve surgery in atrial functional mitral regurgitation compared with degenerative etiology

OBJECTIVE

To analyze and compare the outcomes of mitral valve surgery for atrial functional mitral regurgitation (AFMR) and for degenerative mitral regurgitation (DMR).

METHODS

Patients with AFMR or DMR who underwent mitral valve repair/replacement at 2 institutions between January 2012 and December 2022 were included. Patients <18 years of age and patients undergoing concomitant cardiac surgery (except for the maze procedure or tricuspid annuloplasty) were excluded. Propensity score analysis was used to adjust for baseline differences.

RESULTS

A total of 642 patients were enrolled. After propensity score analysis, 164 patients were classified into the DMR group, and 82 patients were classified into the AFMR group. All matched patients in both groups had atrial fibrillation. In DMR and AFMR, the 5-year freedom from readmission for heart failure and cardiac death was 96.3% in the DMR group versus 88.6% in the AFMR group (P = .045) and freedom from readmission for cardiac death in the 2 groups was 100% and 90.0%, respectively (P = .002). The recurrence rate of significant mitral regurgitation (MR) after mitral valve repair was not significantly different between the 2 groups (P = .699, log-rank test), and the 5-year freedom from MR recurrence (moderate or greater) was 89.8% and 93.0%, respectively. After the maze procedure, significantly more patients in the AFMR group than the DMR group were in junctional rhythm (49.1% vs 3.3%; P < .001) and required permanent pacemaker insertion during the follow-up period (11.4% vs 1.5% after 5 years; P = .041, log-rank test).

CONCLUSIONS

AFMR was associated with acceptable outcomes of mitral valve surgery, and mitral valve repair is a good treatment option. However, significantly more patients were in junctional rhythm after the maze procedure, needing more permanent pacemaker insertion.

Updated pathophysiological overview of functional MR (ventricular and atrial)

Basic mechanism of ventricular functional mitral regurgitation (FMR) is subvalvular tethering. Left ventricular (LV) dilatation, in association with mitral valve (MV) annular dilatation, causes outward displacement of papillary muscles (PMs), which abnormally pulls or tethers MV leaflets, resulting in MV tenting, reduction in leaflets coaptation and MR. Because surgical annuloplasty does shorten distance between anterior and posterior MV annuli to improve coaptation but does not address this subvalvular tethering, ventricular FMR frequently persists or recurs in the chronic stage after surgical annuloplasty. This high incidence of persistent/recurrent MR requires additional procedures to reduce subvalvular tethering. Although patients occasionally show marked improvements after annuloplasty with surgical tethering reduction procedures such as PM approximation, evidence to support benefits of such surgery is limited, requiring further trials. Recently, MV adaptation or MV leaflets tissue growth associated with LV dilatation attracts attention. Patients with larger MV leaflets with significant LV dilatation/dysfunction show less MV tethering and MR compared to those with smaller MV leaflets but with similar LV remodeling, suggesting the protective or beneficial role of MV leaflets tissue growth against LV remodeling. The MV leaflets tissue growth has the potential to lead to novel strategies of treatment for ventricular FMR. It is well known that atrial FMR is frequent in patients with left atrial dilatation, typically in those with isolated atrial fibrillation. The degree of atrial FMR is usually mild, even when it is present, and occasionally moderate, and severe atrial FMR is really rare. It is known that only severe regurgitation causes heart failure in primary MR, resulting in description on indications of surgery or intervention for only severe MR in current guidelines. Therefore, this atrial FMR up to moderate degree did not attract attention for a long time. However, recent studies have shown that patients with only moderate atrial FMR develop severe heart failure, suggesting more aggressive indication of MV surgery or intervention for "moderate" regurgitation in patients with atrial FMR. Therefore, atrial FMR is now recognized highly important. The unveiled malignant nature of atrial FMR arises many questions, including (1) why patients with only moderate atrial FMR develop heart failure? (2) do patients with mild atrial FMR develop heart failure or not?, and many others. Atrial FMR seems even more mysterious after the unveiling of its significance.

Five-year outcomes of different techniques for minimally invasive mitral valve repair in Barlow's disease

OBJECTIVES

Barlow's disease is a specific sub-form of mitral valve (MV) disease, characterized by diffuse excessive tissue and multi segment prolapse. The anterolateral mini-thoracotomy represents the standard access for MV regurgitation in many centres. It still remains unclear which surgical technique provides the best results. Therefore, the aim of this study was to compare operative safety and mid-term outcomes after (i) isolated annuloplasty, (ii) use of additional artificial chordae or (iii) leaflet resection in patients suffering from Barlow's disease undergoing minimally invasive MV repair.

METHODS

A consecutive series of patients suffering from Barlow's disease undergoing minimally invasive MV surgery between 2001 and 2020 were analysed (n = 246). Patients were grouped and analysed according to the used surgical technique. The primary outcome was a modified Mitral Valve Academic Research Consortium combined end-point of mortality, reoperation due to repair failure or reoccurrence of severe mitral regurgitation within 5 years. The secondary outcome included operative success and safety up to 30 days.

RESULTS

No significant difference was found between the 3 surgical techniques with regard to operative safety (P = 0.774). The primary outcome did not differ between groups (P = 0.244). Operative success was achieved in 93.5% and was lowest in the isolated annuloplasty group (77.1%). Conversion to MV replacement was increased in patients undergoing isolated annuloplasty (P < 0.001).

CONCLUSIONS

Isolated annuloplasty, use of additional artificial chordae and leaflet resection represent feasible techniques in Barlow patients undergoing minimally invasive MV surgery with comparable 5-year results. In view of the increased conversion rate in the annuloplasty group, the pathology should not be oversimplified.

Degenerative Mitral Regurgitation Outcomes in Asian Compared With European-American Institutions

Background

Clinical outcome and interventional thresholds for degenerative mitral regurgitation (DMR) were developed in studies of patients at European and American institutions (EAIs), but little is known about patients at Asian institutions (AsIs).

Objectives

This study sought to contrast DMR presentation/management/outcomes of AsI patients vs EAI patients.

Methods

Patients with DMR due to flail leaflet from Hong Kong and Singapore (AsI cohort, n = 737) were compared with EAI patients (n = 682) enrolled in the MIDA (Mitral regurgitation International Database) registry with similar eligibility criteria.

Results

AsI patients presented similar DMR lesion/consequences vs EAI patients, but they were younger, with fewer symptoms (74% vs 44% Class I), more sinus rhythm (83% vs 69%), and lower EuroSCORE II (European System for Cardiac Operative Risk Evaluation II) (0.9 ± 0.5 vs 1.4 ± 1.5; all P < 0.0001). Imaging showed smaller absolute left atrial/ventricular dimensions in AsI patients, belying cardiac dilatation with larger body surface area-indexed diameters (all P < 0.01). Surgical/interventional mitral repair was similarly predominant (90% vs 91%; P = 0.47), and early repair was similarly beneficial (for AsI patients, adjusted HR: 0.28; 95% CI: 0.16-0.49; for EAI patients, HR: 0.32; 95% CI: 0.20-0.49; both P < 0.0001). However, AsI patients underwent fewer interventions (55% ± 2% vs 77% ± 2% at 1 year; P < 0.0001) and incurred excess mortality (adjusted HR: 1.60 [95% CI: 1.13-2.27] vs EAI patients; P = 0.008) at long-term postdiagnosis. Propensity score matching (434 patient pairs), which balanced all clinical characteristics, confirmed that there was undertreatment and excess mortality in the long term in AsI patients with DMR (P < 0.0001).

Conclusions

Imaging may underestimate volume overload in AsI patients due to smaller cardiac cavities related to smaller body size compared with EAI patients with similar mitral lesions and DMR severity. AsI patients enjoy similar mitral repair predominance and early intervention benefits but undergo fewer mitral interventions than EAI patients and incur subsequent excess mortality, suggesting the need to account for imaging and cultural specificity to improve DMR outcomes worldwide.

Quantification of Mitral Regurgitation in Mitral Valve Prolapse by Three-Dimensional Vena Contracta Area: Derived Cutoff Values and Comparison With Two-Dimensional Multiparametric Approach

BACKGROUND

Echocardiographic grading of mitral regurgitation (MR) in mitral valve prolapse (MVP) is challenging. Three-dimensional (3D) vena contracta area (VCA) has been proposed as a valuable method. However, data defining the cutoff values of severity and validation in the subset of patients with MVP are scarce. The aim of this study was to validate the 3D VCA by 3D color-Doppler transesophageal echocardiography (TEE) in patients with MVP and to define the cutoff values of severity grading. The secondary aim was to compare 3D VCA to the effective regurgitant orifice area estimation by proximal isovelocity surface area (EROA-PISA) method.

METHODS

A total of 1,138 patients with at least moderate MR who underwent TEE were included. Three-dimensional VCA was measured, and the cutoff value and area under the curve (AUC) for the prediction of severe MR were estimated by receiver operating characteristic curve using a guideline-suggested multiparametric approach as the reference standard. In a subgroup of patients, 3D regurgitant volume (RV) and 3D fraction were calculated from mitral and left ventricular outflow tract stroke volumes to further validate 3D VCA against a 3D volumetric reference standard.

RESULTS

The optimal 3D VCA cutoff value for predicting severe MR was 0.45 cm2 (specificity, 0.87; sensitivity, 0.90) with an AUC of 0.95 using a multiparametric approach as reference. Three-dimensional VCA had a good linear correlation with EROA-PISA (r = 0.62, P < .05) with larger values compared to EROA-PISA (0.63 cm2 vs 0.44 cm2, P < .05). A cutoff of 0.50 cm2 (AUC of 0.84; sensitivity, 0.78; specificity, 0.78) predicts an EROA-PISA of 0.40 cm2. Three-dimensional VCA had a good linear correlation with 3D RV (r = 0.56, P < .01), with an AUC of 0.86 to predict a 3D fraction >50%.

CONCLUSIONS

The present study suggests 0.45 cm2 as the best cutoff value of 3D VCA to define severe MR in patients with MVP, showing an optimal agreement with the reference standard multiparametric approach and 3D RV.

Left Atrium: A New Prognostic Marker and Therapeutic Target in Secondary Mitral Regurgitation?

Mitral regurgitation (MR) is one of the most common valvular abnormalities worldwide and can be subdivided into primary and secondary causes. Atrial MR consists of a novel type of secondary MR (SMR), most often observed in patients with AF and heart failure with preserved ejection fraction. The main pathophysiological mechanism of atrial MR is mitral valve annular dilatation. Recently published studies have highlighted the clinical significance of left atrium (LA) evaluation in the early diagnosis and prognosis of patients with primary MR. However, there are little data regarding the role of the LA in SMR. The present literature review aims to elucidate the use of the echocardiographic parameters regarding LA evaluation in the prognosis prediction and therapeutic strategy of patients with SMR.

Prevalence and prognostic impact of dynamic atrial functional mitral regurgitation assessed by isometric handgrip exercise

AIMS

In atrial functional mitral regurgitation (aFMR), a considerable proportion of patients displays a discrepancy between symptoms and echocardiographic findings at rest. Exercise testing plays a substantial role in assessing the haemodynamic relevance of mitral regurgitation (MR) and is recommended by current guidelines. Here, we aimed to assess the prevalence, extent, and prognostic impact of exercise-induced changes in patients with aFMR.

METHODS AND RESULTS

Patients with at least mild MR who underwent handgrip exercise echocardiography at the University Hospital Duesseldorf between January 2019 and September 2021 were enrolled. Patients were followed up for 1 year to assess clinical outcomes. Eighty patients with aFMR were included [median age: 80 (77-83) years; 53.8% female]. The median N-terminal pro-brain natriuretic peptide level was 1756 (1034-3340) ng/L. At rest, half of the patients (53.8%) had mild MR, 20 patients (25.0%) had moderate MR, and 17 patients (21.2%) had severe MR. In approximately every fifth patient (17.5%) with non-severe MR at rest, the MR became severe during exercise. Handgrip exercise led to a reclassification of MR severity in 28 patients (35.0%). At 1-year follow-up, adverse events occurred more often in patients with severe MR at rest (76.5%) and exercise-induced dynamic severe MR (66.7%) than in those with non-severe MR (28.6%; P < 0.001).

CONCLUSION

Handgrip exercise during echocardiography revealed exercise-induced changes in aFMR in every third patient. These data may have implications for therapeutic decision-making in symptomatic patients with non-severe aFMR at rest.

The Natural History of Atrial Functional Mitral Regurgitation

BACKGROUND

The natural history of moderate/severe atrial functional mitral regurgitation (AFMR) is unknown.

OBJECTIVES

The authors sought to study the incidence of left ventricular (LV) systolic dysfunction (LVSD), progression or regression of ≥mild-moderate AFMR, and impact on mortality.

METHODS

Adults with left atrial (LA) volume index ≥40 mL/m2, ≥mild-moderate AFMR, and follow-up echocardiogram were followed for incident LVSD (ejection fraction <50% and ≥10% lower than baseline), progression of mild-moderate/moderate AFMR to severe, and persistent regression of AFMR to no/trivial. Relation of AFMR progression or regression as time-dependent covariates with all-cause mortality was studied. Incidence of LVSD was compared with patients with no/mild AFMR matched on age, sex, comorbidities and ejection fraction. Patients were followed until mitral intervention, myocardial infarction, or last follow-up.

RESULTS

A total of 635 patients (median age 75 years, 51% female, 96% mild-moderate/moderate AFMR, 4% severe AFMR) were included. Over a median 2.2 years (Q1-Q3: 1.0-4.3 years), incidence rates per 100 person-years were 3.2 for LVSD (P = 0.52 vs patients with no/mild AFMR), 1.9 for progression of AFMR, and 3.9 for regression. Female sex and larger LA volume index were independently associated with progression, whereas younger age, male sex, absent atrial fibrillation, and higher LA emptying fraction were independently associated with regression. Neither AFMR progression nor regression was independently associated with mortality. Instead, independent risk factors for mortality included older age, concentric LV geometry, and higher estimated LV filling and pulmonary pressures.

CONCLUSIONS

In patients with predominantly mild-moderate/moderate AFMR, regression of MR was more common than progression, but neither was associated with mortality. Instead, diastolic function abnormalities were more important. Over a median 2-year follow-up, LVSD risk was not increased.

Mitral regurgitation in heart failure with preserved ejection fraction: The interplay of valve, ventricle, and atrium

Mitral regurgitation (MR) is highly prevalent among patients with heart failure and preserved ejection fraction (HFpEF). Despite this combination being closely associated with unfavourable outcomes, it remains relatively understudied. This is partly due to the inherent heterogeneity of patients with HFpEF. To address this gap, dissecting HFpEF into mechanism-based phenotypes may offer a promising avenue for advancing our comprehension of these complex intertwined conditions. This review employs the validated CircAdapt model to explore the haemodynamic implications of moderate to severe MR across a well-defined spectrum of myocardial disease, characterized by impaired relaxation and reduced myocardial compliance. Both heart failure and mitral valve disease share overlapping symptomatology, primarily attributed to elevated pulmonary pressures. The intricate mechanisms contributing to these elevated pressures are multifaceted, potentially influenced by diastolic dysfunction, left atrial myopathy, and MR. Accurate evaluation of the haemodynamic and clinical impact of MR necessitates a comprehensive approach, taking into account the characteristics of both the left atrium and left ventricle, as well as their intricate interactions, which may currently be underemphasized in diagnostic practice. This holistic assessment is imperative for enhancing our understanding and refining therapeutic strategies within this patient cohort.

Prevalence of valvular heart disease in cardiac amyloidosis and impact on survival

BACKGROUND

Limited data exists on the prognostic impact of valvular heart disease in cardiac amyloidosis (CA). We therefore sought to define the prevalence of valvular disease in patients with CA and assess the effects of significant valve disease on survival.

METHODS

This multi-center retrospective cohort study included consecutive patients with confirmed transthyretin (TTR) or light chain (AL) amyloidosis. Echocardiographic data closest to the date of amyloid diagnosis was reviewed, and severity was graded according to ASE guidelines. Kaplan-Meier survival analysis was performed to compare survival between patients with moderate or greater valve disease against those with mild or less disease.

RESULTS

We included 345 patients (median age 76 years; 73 % men; 110 AL, 235TTR). The median survival for the total patient cohort with cardiac amyloidosis was 2.92 years, with 30 % of patients surviving at five years after their diagnosis. Median survival comparing AL vs ATTR was 2.58 years vs 2.82 years (p = 0.67) The most common valvular abnormalities in the total cohort were mitral (62 %) and tricuspid (66 %).regurgitation There was a statistically significant difference in median survival between patients with no or mild MR compared to those with moderate or severe MR (2.92 years vs 3.35 years, p = 0.0047) (Fig. 5). There was a statistically significant difference in median survival in patients with no or mild TR compared to those with moderate or severe TR (3.35 years vs 2.3 years, p = 0.015).

CONCLUSION

Our study demonstrates a significant prevalence of mitral and tricuspid regurgitation in CA, with patients with moderate to severe MR and TR having a poorer prognosis.

The high-risk features among patients undergoing mitral valve operation for ischemic mitral regurgitation: The 3-strike score

Objective

Ischemic mitral regurgitation is prevalent and associated with high surgical risk. With the less-invasive option of transcatheter edge-to-edge repair, the optimal patient selection for mitral valve operation for ischemic mitral regurgitation remains unclear. We sought to identify high-risk features in this group to guide patient selection.

Methods

Using the Cardiothoracic Surgery Trial Network's severe ischemic mitral regurgitation trial data, we identified patient and echocardiographic characteristics associated with an increased risk of 2-year mortality using the support vector classifier and Cox proportional hazards model. We identified 6 high-risk features associated with 2-year survival. Patients were categorized into 3 groups, each having 1 or less, 2, or 3 or more of the 6 identified high-risk features.

Results

Among the 251 patients, the median age was 69 (Q1 62, Q3 75) years, and 96 (38%) were female. Two-year mortality was 21% (n = 53). We identified 6 high-risk preoperative features: age 75 years or more (n = 69, 28%), prior sternotomy (n = 49, 20%), renal insufficiency (n = 69, 28%), gastrointestinal bleeding (n = 15, 6%), left ventricular ejection fraction less than 40% (n = 131, 52%), and ventricular end-systolic volume index less than 50 mL/m2 (n = 93, 37%). In patients who had 1 or less, 2, and 3 or more high-risk features, 90-day mortality was 4.2% (n = 5), 9.9% (n = 4), and 20.0% (n = 10), respectively (P = .006), and 2-year mortality was 10% (n = 12), 22% (n = 18), and 46% (n = 23) (P < .001), respectively.

Conclusions

We developed the 3-strike score by identifying high-risk preoperative features for mitral valve surgery for ischemic mitral regurgitation. Patients having 3 or more of such high-risk features should undergo careful evaluation for surgical candidacy given the high early and late mortality after mitral valve operations.

Developing an AI-assisted digital auscultation tool for automatic assessment of the severity of mitral regurgitation: protocol for a cross-sectional, non-interventional study

INTRODUCTION

Mitral regurgitation (MR) is the most common valvular heart disorder, with a morbidity rate of 2.5%. While echocardiography is commonly used in assessing MR, it has many limitations, especially for large-scale MR screening. Cardiac auscultation with electronic stethoscope and artificial intelligence (AI) can be a fast and economical modality for assessing MR severity. Our objectives are (1) to establish a deep neural network (DNN)-based cardiac auscultation method for assessing the severity of MR; and (2) to quantitatively measure the performance of the developed AI-based MR assessment method by virtual clinical trial.

METHODS AND ANALYSIS

In a cross-sectional design, phonocardiogram will be recorded at the mitral valve auscultation area of outpatients. The enrolled patients will be checked by echocardiography to confirm the diagnosis of MR or no MR. Echocardiographic parameters will be used as gold standard to assess the severity of MR, classified into four levels: none, mild, moderate and severe. The study consists of two stages. First, an MR-related cardiac sound database will be created on which a DNN-based MR severity classifier will be trained. The automatic MR severity classifier will be integrated with the Smartho-D2 electronic stethoscope. Second, the performance of the developed smart device will be assessed in an independent clinical validation data set. Sensitivity, specificity, precision, accuracy and F1 score of the developed smart MR assessment device will be evaluated. Agreement on the performance of the smart device between cardiologist users and patient users will be inspected. The interpretability of the developed model will also be studied with statistical comparisons of occlusion map-guided variables among the four severity groups.

ETHICS AND DISSEMINATION

The study protocol was approved by the Medical Ethics Committee of Huzhou Central Hospital, China (registration number: 202302009-01). Informed consent is required from all participants. Dissemination will be through conference presentations and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2300069496.

The added value of three-dimensional transthoracic echocardiography in mitral annular disjunction: a case report

Background

Mitral annular disjunction (MAD) refers to the arrhythmic mitral valve prolapse (MVP) syndrome associated with ventricular arrhythmias and sudden cardiac death. Although the pathophysiology of this disease is still under investigation, specific imaging criteria that establish the diagnosis have been recognized. In this article, we demonstrate most of these criteria using three-dimensional transthoracic echocardiography (3D-TTE) and provide added value in the management of MAD syndrome.

Case presentation

A 50-year-old male patient with recent syncope and a history of mitral regurgitation (MR) and MAD was admitted to our clinic for further investigation. According to our protocol, the patient underwent a complete 3D-TTE, laboratory blood exams, and 24 h ambulatory electrocardiogram (ECG). Our investigation confirmed the presence of MAD syndrome with bileaflet prolapse, severe MR, and non-sustained ventricular tachycardia, necessitating an implantable cardioverter defibrillator (ICD) and surgical mitral valve repair. The 3D-TTE analysis of the mitral valve demonstrated mitral annular systolic expansion and systolic flattening of the saddle-shaped annulus and quantified the extent of the disjunction arc. Additionally, four-dimensional (4D) strain analysis of the left ventricle revealed the presence of fibrosis of the posteromedial papillary muscle and basal inferolateral wall, which are variables that are required for the diagnosis and therapeutic management of MAD syndrome.

Conclusions

3D-TTE and 4D strain offer valuable insights for diagnosing and managing patients with MAD syndrome. This method seems to correlate well with the other imaging modalities and could be included in the management protocol of MAD syndrome.

Potential Effects of Mild Atrial Secondary Mitral Regurgitation in Patients With Isolated Atrial Fibrillation

BACKGROUND

Patients with only moderate atrial secondary mitral regurgitation (asMR) frequently develop heart failure (HF). Mechanisms of HF with moderate asMR and the impact of mild asMR remain unclarified. Although mild/moderate primary mitral regurgitation is compensated by left ventricular (LV) dilatation, the LV is not dilated in asMR. We hypothesized that patients with mild asMR without LV dilatation may have impaired hemodynamics and higher risks of subsequent symptomatic HF deterioration.

METHODS

Stroke volume, cardiac output, and systolic pulmonary artery pressure were measured by echocardiography in 142 patients with isolated atrial fibrillation and 30 healthy controls. The prognosis of patients with isolated atrial fibrillation was followed up.

RESULTS

In the 142 patients with isolated atrial fibrillation, asMR was no/trivial in 55, mild in 83, moderate in 4, while none had severe asMR. Compared with controls and patients with no/trivial asMR, LV end-diastolic volume index was not increased and hemodynamic parameters were abnormal in patients with mild asMR (LV end-diastolic volume index, 65±6 versus 58±8 versus 60±8 mL/m²; stroke volume index, 42±4 versus 35±4 versus 29±6 mL/m²; P<0.001 versus other 2 groups; cardiac output index, 2.8±0.4 versus 2.8±0.5 versus 2.3±0.6 L/min per m²; P<0.001; systolic pulmonary artery pressure, 21±3 versus 26±5 versus 37±9 mm Hg; P<0.001). Although the event-free rate of HF symptomatic deterioration or hospitalization in patients with no/trivial asMR during a median 13.9 months follow-up was 86.9% and 100%, the rate in mild asMR was 59.4% and 85.0% (P<0.001 or P=0.032), respectively.

CONCLUSIONS

In the presence of isolated AF and no compensatory LV dilatation, impaired hemodynamics and higher risks of symptomatic HF deterioration were associated with mild asMR, requiring further studies of causalities.

Outcomes of transcatheter edge-to-edge repair for atrial functional mitral regurgitation

BACKGROUND

The prognostic benefits of transcatheter edge-to-edge repair (TEER) remain unclear in patients with atrial functional mitral regurgitation (AFMR).

AIMS

We aimed to investigate the clinical outcomes of TEER for patients with AFMR.

METHODS

We retrospectively classified functional mitral regurgitation (FMR) patients undergoing TEER into those with AFMR or ventricular FMR (VFMR). A residual MR ≤1+ at discharge was considered optimal mitral regurgitation (MR) reduction, and an elevated mean mitral valve pressure gradient (MPG) was defined as an MPG ≥5 mmHg at discharge. The primary outcome was a composite of all-cause mortality and hospitalisation due to heart failure within one year.

RESULTS

Of 441 FMR patients, 125 patients were considered as having AFMR. Residual MR ≤1+ was associated with a lower risk of the composite outcome in both AFMR and VFMR patients, while an MPG ≥5 mmHg was associated with a higher risk of the composite outcome in patients with AFMR but not with VFMR. AFMR patients with residual MR ≤1+ and an MPG ≥5 mmHg, as well as those with residual MR >1+, had a higher incidence of the composite outcome than those with residual MR ≤1+ and an MPG <5 mmHg (50.7%, 41.8%, and 14.3%, respectively; p<0.001). This association was consistent after adjustment for clinical and echocardiographic characteristics.

CONCLUSIONS

An MR reduction to ≤1+ following TEER was associated with a lower risk of clinical outcomes in patients with AFMR, while an MPG ≥5 mmHg was related to a higher risk of clinical outcomes. Optimal MR reduction by TEER may have potential benefits on the prognosis of patients with AFMR, although the prognostic benefit may be attenuated by an elevated MPG.

Mitral Valve Intervention in Elderly or High-Risk Patients: A Review of Current Surgical and Interventional Management

Mitral regurgitation is a prevalent valvular disease, and its management has gained increasing importance because of the aging population. Although traditional surgery remains the gold standard, the field of transcatheter therapies, including transcatheter edge-to-edge repair and, more recently transcatheter mitral valve replacement are advancing and are being explored as viable alternatives, particularly for patients at high surgical risk. It is essential to emphasize the necessity of a multidisciplinary team approach, involving specialized valve teams, imaging experts, cardiac anaesthesiologists, and other relevant specialists, is crucial in achieving optimal outcomes. Furthermore, proper execution of procedures, postprocedural care, and diligent follow-up for these patients are essential components for successful results. It is essential to underscore that traditional mitral valve surgery continues to play a significant role. Simultaneously, it is important to acknowledge the expanding array of transcatheter interventions available for this specific patient population.

Echocardiographic quantification of mitral apparatus morphology and dynamics in patients with dilated cardiomyopathy

Mitral regurgitation is among the most common valvular heart diseases. Mitral regurgitation in patients with dilated cardiomyopathy is a complex pathology involving annular dilatation, papillary muscle displacement, systolic leaflet tethering, and left ventricular remodeling. Quantification of mitral apparatus damage in these patients is essential for successful interventional and surgical therapy. Mitral regurgitation in the presence of dilated cardiomyopathy is classified as Carpentier type IIIB, with restricted leaflet mobility as a standard feature. Echocardiography allows accurate evaluation of the complex anatomy and function of the mitral apparatus. Updated guidelines recommend two-dimensional followed by systematic three-dimensional echocardiographic evaluation in patients with mitral regurgitation. New three-dimensional echocardiographic software packages provide many parameters that help identify the precise morphology and function of the various components of the mitral apparatus, helping to determine the etiology of mitral regurgitation and evaluate disease severity. This review provides the first point-by-point approach to the assessment of all old and new echocardiographic methods, from the simplest to the most complex, used to examine the components of the mitral valve apparatus in patients with dilated cardiomyopathy. Although these parameters are still under research, this information will be helpful for establishing therapeutic procedures in a disease with a poor prognosis.

Impact of Transcatheter Edge-to-Edge Mitral Valve Repair on Atrial Functional Mitral Regurgitation from the GIOTTO Registry

Atrial functional mitral regurgitation (aFMR) has a peculiar pathophysiology that may have distinctive outcomes. We investigated the impact of transcatheter edge-to-edge repair in aFMR compared with other FMR etiologies. The GIOTTO (GIse registry Of Transcatheter treatment of MR) is a multicenter, prospective study enrolling patients with symptomatic MR treated with MitraClip up to 2020. We categorized patients with FMR as aFMR, ischemic FMR (iFMR), and nonischemic ventricular FMR (niFMR). The clinical end points were defined according to the Mitral Valve Academic Research Consortium. Of 1,153 patients, 6% had aFMR, 47% iFMR, and 47% niFMR. Patients with aFMR were older, mostly women, and had a higher atrial fibrillation rate. They had better left ventricular ejection fraction and smaller left ventricular volumes, with no difference in mitral effective regurgitant orifice area. The acute device and procedural success rates were similar among the groups. At the longest available follow-up (median 478 days, interquartile range 91 to 741 days), the rate of MR ≥2+ was similar among the groups. Patients with aFMR had a lower rate of cardiovascular death and heart failure than patients with iFMR (hazard ratio [HR] 0.43, p = 0.02) and niFMR (HR 0.45, p = 0.03). The aFMR etiology remained independently associated with the composite outcome, together with postprocedural MR ≤1+ (HR 0.63, p <0.01) and peripheral arteriopathy (HR 1.82, p = 0.003). The results of this GIOTTO subanalysis suggested that aFMR is less prevalent and associated with better outcomes compared with other causes of FMR treated by transcatheter edge-to-edge repair. Postprocedural MR >1+, peripheral vasculopathy, non-aFMR were independent predictors of worse outcomes.

Assessment of mitral valve geometry in nonvalvular atrial fibrillation patients with or without ventricular dysfunction: insights from high volume rate three-dimensional transesophageal echocardiography

Meticulous understanding of the mechanisms underpinning mitral regurgitation in atrial fibrillation (AF) patients is crucial to optimize therapeutic strategies. The morphologic characteristics of mitral valves in atrial functional mitral regurgitation (FMR) patients with and without left ventricular (LV) dysfunction were evaluated by high volume rate (HVR) three-dimensional transesophageal echocardiography (3D-TEE). In our study, 68 of 265 AF patients who underwent 3D-TEE were selected, including 36 patients with AF, FMR, and preserved LV function (AFMR group) and 32 patients with AF, FMR, and LV dysfunction (VFMR group). In addition, 36 fever patients without heart disease were included in the control group. Group comparisons were performed by one-way analysis of variance for continuous variables. The left atrium (LA) was enlarged in the AFMR and VFMR groups compared with the control group. The mitral annulus (MA) in the AFMR group was enlarged and flattened compared with the control group and was smaller than in the VFMR group. The annulus area fraction was significantly diminished in the AFMR and VFMR groups, indicative of reduced MA contractility. The posterior mitral leaflet (PML) angle was smallest in the AFMR group and largest in the control group, whereas the distal anterior mitral leaflet angle did not significantly differ among the three groups. LA remodeling causes expansion of the MA and reduced MA contractility, disruption of the annular saddle shape, and atriogenic PML tethering. Comparison of atrial FMR patients with and without LV dysfunction indicates that atriogenic PML tethering is an important factor that aggravates FMR. HVR 3D-TEE improves the 3D temporal resolution greatly.

Impact of eccentric jet on outcomes in patients with atrial functional mitral regurgitation: An echocardiographic study

BACKGROUND

Previous studies have reported the mechanisms underlying atrial functional mitral regurgitation (A-FMR). Recently, A-FMR subtypes based on mitral regurgitation (MR) mechanisms were proposed: "central jet" due to insufficient leaflet remodeling and "eccentric jet" due to atriogenic tethering. However, their prognostic value remains unclear. Therefore, this study investigated the impact of A-FMR subtypes on clinical outcomes.

METHODS

Outpatients with significant A-FMR between January 2013 and December 2016 were retrospectively reviewed. They were classified into two subtypes according to the MR jet's direction. All-cause mortality, heart failure hospitalization, and any mitral valve interventions were the primary composite endpoint.

RESULTS

Among 101 patients with significant A-FMR, 32% had eccentric jet. The primary endpoint was observed in 56 patients during the follow-up period (median 0.7 years, range 0.1-4.2 years). Kaplan-Meier curves demonstrated that the composite endpoint was higher among patients with eccentric jet than those with central jet (log-rank p < 0.001). Eccentric jet (hazard ratio [HR] 2.46, 95% confidence interval [CI] 1.28-4.73; p = 0.007), age (HR 1.06, 95% CI 1.02-1.11; p = 0.002), symptoms (HR 6.22, 95% CI 2.18-17.8; p < 0.001), severe MR (HR 3.97, 95% CI 1.92-8.18; p < 0.001), and significant tricuspid regurgitation (TR; HR 2.00, 95% CI 1.01-3.97; p = 0.047) were independent predictors of the composite endpoint.

CONCLUSIONS

Patients with eccentric jet had poorer outcomes than those with central jet. Eccentric jet, age, symptoms, severe MR, and significant TR were independently associated with poor outcomes.

Incidence, risk factors, and outcomes of atrial functional mitral regurgitation in patients with atrial fibrillation or sinus rhythm

AIMS

Atrial functional mitral regurgitation (AFMR) has been associated with atrial fibrillation (AF) and heart failure with preserved ejection fraction. However, data on incident AFMR are scarce. We aimed to study the incidence, risk factors, and clinical significance of AFMR in AF or sinus rhythm (SR).

METHODS AND RESULTS

Adults with new diagnosis of AF and adults in SR were identified. Patients with >mild MR at baseline, primary mitral disease, cardiomyopathy, left-sided valve disease, previous cardiac surgery, or with no follow-up echocardiogram were excluded. Diastolic dysfunction (DD) was indicated by ≥2/4 abnormal diastolic function parameters [mitral medial e', mitral medial E/e', tricuspid regurgitation velocity, left atrial volume index (LAVI)]. Overall, 1747 patients with AF and 29 623 in SR were included. Incidence rate of >mild AFMR was 2.6 per 100 person-year in new-onset AF and 0.7 per 100 person-year in SR, P < 0.001. AF remained associated with AFMR in a propensity score-matched analysis based on age, sex, and comorbidities between AF and SR [hazard ratio: 3.80 (95% confidence interval 3.04-4.76)]. Independent risk factors associated with incident AFMR were age ≥65 years, female sex, LAVI, and DD in both AF and SR, in addition to rate (vs. rhythm) control in AF. Incident AFMR was independently associated with all-cause death in both groups (both P < 0.001).

CONCLUSIONS

AF conferred a three-fold increase in the risk of incident AFMR. DD, older age, left atrial size, and female sex were independent risk factors in both SR and AF, while rhythm control was protective. AFMR was universally associated with worse mortality.

Association of Functional Tricuspid Regurgitation and All-Cause Mortality in Ischemic Heart Failure Varies by Left Atrial Size: A Prospective Cohort Study

This study aimed to evaluate whether the mortality risk of tricuspid regurgitation (TR) varies by left atrial (LA) size in patients with heart failure (HF). In total, 2,234 patients with ischemic HF were included. Participants were categorized as normal LA group and LA enlargement group based on the guideline recommendations, and in each group, patients were further classified as non/mild TR group and moderate/severe TR group according to echocardiographic examination. All-cause mortality was used as the only end point, and comparisons were conducted between the TR degree groups stratified by LA size status. Propensity-matched analyses and restricted cubic splines were performed to verify the robustness of the results. Of 2,234 patients with ischemic HF participants, 1,002 (44.9%) had LA enlargement and 294 (13.2%) had moderate/severe TR. After a median follow-up of 3.02 years (7,140 person-years), 453 patients (20.3%) died. After adjusting for the covariates, the higher mortality risk of moderate/severe TR was only observed in the normal LA diameter group (hazard ratio 1.64, 95% confidence interval 1.02 to 2.65) rather than the LA enlargement group (hazard ratio 0.96, 95% confidence interval 0.69 to 1.34). A significant interaction of TR degree was observed between the normal LA size group and the LA enlargement group. The relation was consistent in the propensity-matching cohort and in the restricted cubic splines analysis. In conclusion, mortality rate and prevalence of moderate/severe TR were high in patients with ischemic HF. Moderate/severe TR is significantly associated with all-cause mortality in those with normal LA diameter. The mechanisms underlying these observations merit further investigation.

Transcatheter edge-to-edge repair for chronic functional mitral regurgitation in patients with very severe left ventricular dysfunction

BACKGROUND

There is scarce data on transcatheter edge-to-edge repair (TEER) for chronic functional mitral regurgitation (FMR) in the setting of very severe left ventricular dysfunction (LVD), defined by a left ventricular ejection fraction (LVEF) of <20%.

METHODS

We retrospectively explored periprocedural characteristics and one-year clinical and echocardiographic outcomes of consecutive patients with chronic FMR and very severe LVD who underwent an isolated, first-time TEER. The composite of all-cause mortality or heart failure hospitalizations constituted the primary outcome.

RESULTS

Ninety-six patients (median age 69 [IQR, 55-76] years, 64 (66.7%) males, median LVEF 15 [IQR, 12-17] %) were included. In 47 (49.0%), TEER was performed urgently or in the setting of hemodynamic instability. Almost all procedures (98.0%) were technically successful, leading to ≤moderate MR in 94.7% and 90.7% of cases by 1-month and 1-year, respectively. New York Heart Association class ≤II was maintained in 60.0% of patients. One-year survival and freedom from the primary outcome were 74.0% and 50.0%, respectively. Functional and echocardiographic improvement compared to baseline was independent of procedural urgency, hemodynamic stability, and downstream left ventricular assist device implantation / heart transplantation (n = 12). Mortality was not predicted by COAPT exclusion criteria, nor was the primary outcome discriminated by published risk models.

CONCLUSION

TEER for chronic FMR is feasible, safe, and efficacious in selected patients with very severe LVD. Preprocedural risk stratification in this population may be optimized.

Outcomes of transcatheter edge-to-edge repair for atrial functional mitral regurgitation: A meta-analysis of observational studies

BACKGROUND

Transcatheter edge-to-edge repair (TEER) may have potential benefits in the treatment of atrial functional mitral regurgitation (AFMR), but robust evidence is currently lacking. We conducted a systematic review and meta-analysis to investigate the clinical outcomes of TEER for AFMR, including comparisons to ventricular functional MR (VFMR).

METHODS

MEDLINE and EMBASE were searched through January 2023 to identify studies eligible for analysis. The primary outcome was postprocedural MR severity. Postprocedural New York Heart Association (NYHA) functional class classification and all-cause mortality were also evaluated. Outcomes were stratified into short term (postprocedure to 6 months) and long term (6 months to 2 years).

RESULTS

A total of eight observational studies met the inclusion criteria, enrolling 539 AFMR and 3486 VFMR patients. Postprocedural MR grade ≤2 in the AFMR group was observed in 93.7% (454/491 patients; 95% confidence interval (CI), 91.1%-96.2%, I2  = 24.3%) and 97.1% (89/93 patients; 95% CI, 92.9%-100%, I2  = 26.4%) in short- and long-term follow-up, respectively. There was no difference in the rates of postprocedural MR grade ≤2 between AFMR and VFMR either in short-term (risk ratio [RR], 1.00 [95% CI, 0.95-1.06]; p = 0.90; I2  = 53%) or long-term follow-up (RR, 1.08 [95% CI, 0.89-1.32]; p = 0.44; I2  = 22%). Similarly, no difference was observed between AFMR and VFMR in the rates of postprocedural NYHA class ≤2 or all-cause mortality.

CONCLUSION

TEER provides similar clinical outcomes for AFMR and VFMR. A high rate of MR grade ≤2 was observed in patients at both short- and long-term follow-ups. Further prospective studies with TEER versus medical therapy and/or rhythm control for AFMR are warranted.