Comparison of Early Surgery Versus Conventional Treatment in Asymptomatic Severe Mitral Regurgitation

2023 Korean Society of Echocardiography position paper for the diagnosis and management of valvular heart disease, part II: mitral and tricuspid valve disease

This manuscript represents the official position of the Korean Society of Echocardiography on valvular heart diseases. This position paper focuses on the diagnosis and management of valvular heart diseases with referring to the guidelines recently published by the American College of Cardiology/American Heart Association and the European Society of Cardiology. The committee sought to reflect national data on the topic of valvular heart diseases published to date through a systematic literature search based on validity and relevance. In the part II of this article, we intend to present recommendations for diagnosis and treatment of mitral valve disease and tricuspid valve disease.

Navigating Asymptomatic Mitral Regurgitation: Diagnostic Dilemmas and Treatment Strategies

This case report explores the complexities involved in the diagnosis and management of asymptomatic mitral regurgitation (MR) in a 64-year-old male presenting with an incidental systolic murmur. Torrential MR with flail mitral valve (MV) segments was identified through comprehensive imaging and clinical evaluation, including echocardiography and catheterization. The discussion highlights the nuances of surgical timing, emphasizing the importance of tailored approaches based on left ventricular (LV) function and dilation. This report sheds light on the evolving landscape of managing asymptomatic MR, underscoring the need for balancing surveillance with proactive intervention to optimize patient outcomes.

Outcomes and quality of life in patients receiving mitral surgery for asymptomatic disease

Objectives

We sought to characterize the demographics, outcomes, and quality of life of asymptomatic patients undergoing mitral valve surgery at our center over a 10-year period.

Methods

Adults undergoing mitral surgery were retrospectively reviewed between 2010 and 2019. Patients were included if deemed asymptomatic by review of referring cardiologist and surgeon consultation. Patients were administered a telephone survey consisting of the Kansas City Cardiomyopathy Questionnaire as well as free-response regarding satisfaction surrounding their operation. Outcomes included survival, Kansas City Cardiomyopathy Questionnaire metrics, and thematic analysis of free response questions.

Results

A total of 145 patients were identified who were deemed asymptomatic. Their average age was 60.3 ± 12.1 years, and 71% were male. No patients had endocarditis, and 34% had decreased ejection fraction (<60%). Repair was achieved in 95% of patients. Median length of stay was 6 (5-8) days. Ten-year survival was 91%, with no differences noted by ejection fraction. Composite Kansas City Cardiomyopathy Questionnaire score was 100 (96-100). The lowest component score was "Quality of Life," with 22% of patients reporting being "mostly satisfied" with present cardiac status. Most common themes expressed were gratitude with surgery results (58%), satisfaction with being able to stay active (23%), and happiness with early disease treatment (21%). Only 1 patient (0.7%) expressed regret with surgery choice.

Conclusions

Mitral surgery for asymptomatic disease can be performed with good long-term outcomes in select patients, and the majority experience excellent quality of life and satisfaction with current health. Continued assessments of quality of life are important in evaluating outcomes of mitral surgery as indications grow.

Left ventricular ejection fraction: clinical, pathophysiological, and technical limitations

Risk stratification of cardiovascular death and treatment strategies in patients with heart failure (HF), the optimal timing for valve replacement, and the selection of patients for implantable cardioverter defibrillators are based on an echocardiographic calculation of left ventricular ejection fraction (LVEF) in most guidelines. As a marker of systolic function, LVEF has important limitations being affected by loading conditions and cavity geometry, as well as image quality, thus impacting inter- and intra-observer measurement variability. LVEF is a product of shortening of the three components of myocardial fibres: longitudinal, circumferential, and oblique. It is therefore a marker of global ejection performance based on cavity volume changes, rather than directly reflecting myocardial contractile function, hence may be normal even when myofibril's systolic function is impaired. Sub-endocardial longitudinal fibers are the most sensitive layers to ischemia, so when dysfunctional, the circumferential fibers may compensate for it and maintain the overall LVEF. Likewise, in patients with HF, LVEF is used to stratify subgroups, an approach that has prognostic implications but without a direct relationship. HF is a dynamic disease that may worsen or improve over time according to the underlying pathology. Such dynamicity impacts LVEF and its use to guide treatment. The same applies to changes in LVEF following interventional procedures. In this review, we analyze the clinical, pathophysiological, and technical limitations of LVEF across a wide range of cardiovascular pathologies.

Unique Aspects of Women's Valvular Heart Diseases: Impact for Diagnosis and Treatment

Valvular heart diseases (VHDs) are a major cause of cardiovascular morbidity and mortality worldwide. As degenerative and functional mechanisms represent the main etiologies in high-income countries are degenerative and functional, while in low income countries etiologie is mostly rheumatic. Although therapeutic options have evolved considerably in recent years, women are consistently diagnosed at later stages of their disease, are delayed in receiving surgical referrals, and exhibit worse postoperative outcomes, compared to men. This difference is a result of the historical underrepresentation of women in studies from which current guidelines were developed. However, in recent years, important research, including more female patients, has been conducted and has highlighted substantial sex-specific differences in the etiology, diagnosis, and treatment of VHDs. Systematic consideration of these sex-specific differences in VHD patients is crucial for providing equitable healthcare and optimizing clinical outcomes in both female and male patients. Hence, this review aims to explore implications of sex-specific particularities for diagnosis, treatment options, and outcomes in women with VHDs.

Tricuspid annular area and leaflets stretch are associated with functional tricuspid regurgitation - insights from three-dimensional transesophageal echocardiography

BACKGROUND

The presence of functional tricuspid regurgitation (TR) is associated with mortality and morbidity. Although uniform management with a tricuspid annuloplasty ring is currently considered as a standard surgical procedure, high rates of residual TR despite annuloplasty are reported. Therefore, the identification of the TR mechanisms would be necessary to provide personalized treatment for each TR patient.

METHODS

This study population consisted of 106 patients with mitral regurgitation (MR) who were scheduled for procedure. Transthoracic and transesophageal echocardiography were performed prior to mitral valve intervention. We performed three-dimensional quantitative assessment including tricuspid annular (TA) area and the distance between the three commissures of tricuspid valve.

RESULTS

Significant TR, which is defined as moderate or greater TR, was detected in 23 (22%). TA area (P < 0.01), the distance of septal-leaflet length (SL) (P = 0.03) and posterior-leaflet length (PL) (p = 0.02) were significantly associated with significant TR, while TA diameter assessed by transthoracic echocardiography was not. When patients were divided into four groups according to SL and PL, the group with longer SL and PL had a significantly higher incidence of significant TR (P < 0.01).

CONCLUSIONS

Greater stretch of the septal and posterior leaflet between commissures and larger TA area are associated with significant TR in patients with severe MR. In order to prevent TR recurrence, the intervention of the septal leaflet in tricuspid annuloplasty may be beneficial. The precise implement of three-dimensional transesophageal echocardiography of tricuspid valve is valuable for a personalized strategy of tricuspid annuloplasty.

Data-driven mortality risk prediction of severe degenerative mitral regurgitation patients undergoing mitral valve surgery

AIMS

The outcomes of mitral valve replacement/repair (MVR) in severe degenerative mitral regurgitation (MR) patients depend on various risk factors. We aimed to develop a risk prediction model for post-MVR mortality in severe degenerative MR patients using machine learning.

METHODS AND RESULTS

Consecutive severe degenerative MR patients undergoing MVR were analysed (n = 1521; 70% training/30% test sets). A random survival forest (RSF) model was constructed, with 3-year post-MVR all-cause mortality as the outcome. Partial dependency plots were used to define the thresholds of each risk factor. A simple scoring system (MVR-score) was developed to stratify post-MVR mortality risk. At 3 years following MVR, 90 patients (5.9%) died in the entire cohort (59 and 31 deaths in the training and test sets). The most important predictors of mortality in order of importance were age, haemoglobin, valve replacement, glomerular filtration rate, left atrial dimension, and left ventricular (LV) end-systolic diameter. The final RSF model with these six variables demonstrated high predictive performance in the test set (3-year C-index 0.880, 95% confidence interval 0.834-0.925), with mortality risk increased strongly with left atrial dimension >55 mm, and LV end-systolic diameter >45 mm. MVR-score demonstrated effective risk stratification and had significantly higher predictability compared to the modified Mitral Regurgitation International Database score (3-year C-index 0.803 vs. 0.750, P = 0.034).

CONCLUSION

A data-driven machine learning model provided accurate post-MVR mortality prediction in severe degenerative MR patients. The outcome following MVR in severe degenerative MR patients is governed by both clinical and echocardiographic factors.

Predictability and durability of mitral valve repair in patients with severe degenerative mitral regurgitation in medium sized centres

INTRODUCTION

Mitral valve repair (MVr) is now the treatment of choice to correct severe degenerative mitral regurgitation (MR). Repair rates vary greatly from centre to centre, and the concept of heart valve centres of excellence has been established.

OBJECTIVE

The purpose of this study was to see whether large international centre repair rates, and outcomes, are transferrable to medium-sized centres with an interest in mitral repair.

METHODS

Between 2011 and 2018, a total of 346 patients underwent mitral valve surgery by a single surgeon. Of these, 238 consecutive patients had repairs, or attempted repairs for degenerative MR, and are included in this study.

RESULTS

The study sample consisted of 71% male patients and had a mean age of 64.4 ± 12.3 years; 66% of the study population had concomitant procedures. The overall repair rate in this cohort is 99%. Mean follow up was 3.7 ± 1.9 years. At 5 years, the freedom from MR ≥ 3+ was 95.9 ± 1.9% and at 7 years 91.1 ± 3.8%. Freedom from reoperation at 5 years was 92.9 ± 3.7%, while the 5 years actuarial survival was 89.1 ± 3.7%. On a multivariate analysis, predischarge echo grade was associated with higher risk of future reoperation (odds ratio (OR) = 21.82, p = 0.05). Only age (OR = 1.3, p = 0.03) was predictive of long-term survival.

CONCLUSIONS

In specialised medium-sized heart centres, where the surgical team have undergone specialist mitral training, favourable short- and long-term outcomes are achievable with mitral repair rates similar to those from large international centres of excellence. In these heart centres, early surgery should be considered for all patients with severe degenerative MR.

Socioeconomic disparities in midterm outcomes after repair for degenerative mitral regurgitation

OBJECTIVE

The influence of socioeconomic disparities on survival after mitral repair is poorly defined. We examined the association between socioeconomic disadvantage and midterm outcomes of repair in Medicare beneficiaries with degenerative mitral regurgitation.

METHODS

US Centers for Medicare and Medicaid Services data were used to identify 10,322 patients undergoing isolated first-time repair for degenerative mitral regurgitation between 2012 and 2019. Zip code-level socioeconomic disadvantage was dichotomized with the Distressed Communities Index, which incorporates education level, poverty, unemployment, housing security, median income, and business growth; those with Distressed Communities Index score ≥80 were classified as distressed. The primary outcome was survival, censored at 3 years. Secondary outcomes included cumulative incidences of heart failure readmission, mitral reintervention, and stroke.

RESULTS

Of the 10,322 patients undergoing degenerative mitral repair, 9.7% (n = 1003) came from distressed communities. Patients from distressed communities underwent surgery at lower volume centers (11 vs 16 cases/year) and traveled further for surgical care (40 vs 17 miles) (both P values < .001). At 3 years, unadjusted survival (85.4%; 95% CI, 82.9%-87.5% vs 89.7%; 95% CI, 89.0%-90.4%) and cumulative incidence of heart failure readmission (11.5%; 95% CI, 9.6%-13.7% vs 7.4%; 95% CI, 6.9%-8.0%) were worse in patients from distressed communities (all P values < .001), whereas mitral reintervention rates were similar (2.7%; 95% CI, 1.8%-4.0% vs 2.8%; 95% CI, 2.5%-3.2%; P = .75). After adjustment, community distress was independently associated with 3-year mortality (hazard ratio, 1.21; 95% CI, 1.01-1.46) and heart failure readmissions (hazard ratio, 1.28; 95% CI, 1.04-1.58).

CONCLUSIONS

Community-level socioeconomic distress is associated with worse outcomes in degenerative mitral repair among Medicare beneficiaries.

Clinical and Prognostic Implications of Cardiopulmonary Exercise Stress Echocardiography in Asymptomatic Degenerative Mitral Regurgitation

The current guidelines recommend intervention in severe degenerative mitral regurgitation (MR) in symptomatic patients or asymptomatic patients with left ventricular dilatation or dysfunction. The insidious onset of symptoms may mean that patients do not report their symptoms. The role of systematic exercise testing for symptoms in MR is not clearly defined. A total of 97 patients with moderate to severe asymptomatic MR underwent exercise echocardiography combined with cardiopulmonary exercise testing. The predictors of exercise-induced dyspnea, symptom-free survival, and mitral valve intervention were identified. A total of 18 patients (19%) developed limiting dyspnea on exercise. Spontaneous symptom-free survival at 24 months was significantly higher in those without exercise-induced symptoms than those with exercise-induced symptoms, p <0.0001. The only independent predictors of spontaneous symptoms at 2 years were effective regurgitant orifice area (odds ratio 27.45, 95% confidence interval [CI] 1.43 to 528.40, p = 0.03) and exercise-induced symptoms (odds ratio 11.56, 95% CI 1.71 to 78.09, p = 0.01). The only independent predictor of surgery was indexed left ventricular systolic volumes (odds ratio 1.17, 95% CI 1.04 to 1.30, p = 0.006). Where only the patients who underwent surgery due to symptoms were included, the only independent predictor was exercise-induced symptoms (odds ratio 13.94, 95% CI 1.39 to 140.27, p = 0.025). In conclusion, in patients with primary asymptomatic degenerative MR, 1/5 develop revealed symptoms during exercise. This predicts a subsequent development of spontaneous symptoms and mitral valve intervention due to symptoms.

Long-term outcomes in distinct phenogroups of patients with primary mitral regurgitation undergoing valve surgery

OBJECTIVES

Patients with mitral regurgitation (MR) may be heterogeneous with different risk profiles. We aimed to identify distinct phenogroups of patients with severe primary MR and investigate their long-term prognosis after mitral valve (MV) surgery.

METHODS

The retrospective cohort of patients with severe primary MR undergoing MV surgery (derivation, n=1629; validation, n=692) was analysed. Latent class analysis was used to classify patients into subgroups using 15 variables. The primary outcome was all-cause mortality after MV surgery.

RESULTS

During follow-up (median 6.0 years), 149 patients (9.1%) died in the derivation cohort. In the univariable Cox analysis, age, female, atrial fibrillation, left ventricular (LV) end-systolic dimension/volumes, LV ejection fraction, left atrial dimension and tricuspid regurgitation peak velocity were significant predictors of mortality following MV surgery. Five distinct phenogroups were identified, three younger groups (group 1-3) and two older groups (group 4-5): group 1, least comorbidities; group 2, men with LV enlargement; group 3, predominantly women with rheumatic MR; group 4, low-risk older patients; and group 5, high-risk older patients. Cumulative survival was the lowest in group 5, followed by groups 3 and 4 (5-year survival for groups 1-5: 98.5%, 96.0%, 91.7%, 95.6% and 83.4%; p<0.001). Phenogroups had similar predictive performance compared with the Mitral Regurgitation International Database score in patients with degenerative MR (3-year C-index, 0.763 vs 0.750, p=0.602). These findings were reproduced in the validation cohort.

CONCLUSION

Five phenogroups of patients with severe primary MR with different risk profiles and outcomes were identified. This phenogrouping strategy may improve risk stratification when optimising the timing and type of interventions for severe MR.

Feasibility study of automated cardiac motion quantification to assess left ventricular function in type 2 diabetes

The global incidence of diabetes and related complications is gradually increasing, with cardiovascular complications being the leading cause of death in the diabetic population. The purpose of this study was to examine left ventricular function in individuals with type 2 diabetes mellitus (T2D) and conduct a feasibility analysis using automated cardiac motion quantification (aCMQ) approach. A total of 150 T2D patients with a history of diabetes mellitus dating back more than 10 years were chosen, and we treated 87 patients with T2D that had been present for less than 15 years as group I, 63 patients with T2D that had been present for more than 15 years as group II, and 50 healthy volunteers as the control group. From the three groups, clinical information, conventional ultrasonography parameters, and mitral annular plane systolic excursion (MAPSE) parameters were gathered. aCMQ technique was used to collect longitudinal strain and circumferential strain in the left ventricle. Tissue motion mitral annular displacement technique (TMAD) in aCMQ was used to collect parameters related to TMAD, and cardiac motion quantification (CMQ) was used to collect two-dimensional global longitudinal strain (2D-GLS) to compare the degree of difference between the aforementioned three groups. The differences between longitudinal strain groups in aCMQ were all statistically significant and gradually decreased with increasing disease duration. Most TMAD parameters were lower in groups I and II than in the control group, and TMAD parameters gradually decreased with increasing disease duration. The results of the LV global longitudinal strain and 2D-GLS using Bland-Altman analyses showed high agreement between and within groups, Pearson correlation analysis showed a significant positive correlation (r = 0.18, P < 0.05), and the AUC of ROC curves predicting the value of left ventricular function in patients with T2D was 0.723 and 0.628, respectively. With significant positive correlations between MAPSE, s', and the majority of the TAMD parameters (P < 0.05), TAMD, MAPSE, and s' demonstrated high inter- and intra-group agreement using Bland-Altman analyses, and the three had predictive value in assessing left ventricular function in T2D patients by ROC curve. Reduced longitudinal strain and reduced mitral annular displacement were seen in patients with different disease stages of T2D, so the application of aCMQ and TAMD was effective in detecting altered left ventricular function in patients with T2D. aCMQ had higher value in predicting left ventricular function in patients with T2D compared to CMQ for overall longitudinal strain, and the software performed the depiction automatically, reducing manual errors. MAPSE parameters and s ' can replace the TMAD technique for assessing mitral annular motion and was simpler to perform, saving operational time.

Watchful surgery in asymptomatic mitral valve prolapse

The most common organic etiology of mitral regurgitation is degenerative and consists of mitral valve prolapse (MVP). Volume overload because of mitral regurgitation is the most common complication of MVP. Advocating surgery before the consequences of volume overload become irreparable restores life expectancy, but carries a risk of mortality in patients who are often asymptomatic. On the other hand, the post-surgical outcome of symptomatic patients is dismal and life expectancy is impaired. In the present article, we aim to bridge the gap between these two therapeutic approaches, unifying the concepts of watchful waiting and early surgery in a "watchful surgery approach".

Prevalence and clinical associations of mitral and aortic regurgitation in patients with aortic stenosis

BACKGROUND

Most guidelines directing clinicians to manage valve disease are directed at single valve lesions. Limited data exists to direct our understanding of how concomitant valve disease impacts the left ventricle (LV).

METHODS

We identified 2817 patients with aortic stenosis (AS) from the echocardiography laboratory database between September 2012 and June 2018 who had a LV ejection fraction (EF) ≥50%. LV mass, LV mass index, LV systolic pressure (systolic blood pressure + peak aortic gradient). Covariates were collected from the electronic medical record. Multi-variate analysis of covariance was used to generate adjusted comparisons.

RESULTS

Our population was 66% female, 17% African-American with a mean age of 65 years. Of note, 7.3% were noted to have significant (moderate/severe) aortic regurgitation (AR), and 11% had significant (moderate/severe) mitral regurgitation (MR). Adjusting for covariates at different levels, significant MR had a much stronger association with heart failure compared to those with significant AR (p < .001 vs. p = .313, respectively) at all levels of adjustment. Both significant mitral and AR exhibited an association with increasing left ventricular mass, even with adjustment for baseline demographics and clinical features (p < .001 vs. p = .007, respectively).

CONCLUSION

In patients with AS, 16% also experience at least moderate MR or AR. Further, significant MR has a stronger association with heart failure than significant AR, even though both increase left ventricular mass. Those with moderate AS and significant MR or AR experience similar or higher levels of heart failure compared to severe AS without regurgitation. Mixed valve disease merits further studies to direct longitudinal management.

Frühe Herzklappentherapie bei asymptomatischen Patienten – was gilt schon jetzt?

Bei einer asymptomatischen hochgradigen Aortenklappenstenose (AS) mit normaler linksventrikulärer Funktion sollte eine „Watchful-Waiting“-Strategie verfolgt werden. Asymptomatische Patienten mit Risikofaktoren, wie sehr schwere AS, schwere kalzifizierter AS oder 3-fach erhöhtem proBNP-Level, können bei niedrigem operativem Risiko eine Intervention erhalten. Erste randomisierte Studien weisen auf einen Vorteil des frühzeitigen Aortenklappenersatzes bei niedrigem OP-Risiko hin.

Für Patienten mit einer asymptomatischen hochgradigen Aortenklappeninsuffizienz sollte bei niedrigem operativem Risiko bereits frühzeitig eine OP erwogen werden, wenn sich Zeichen der linksventrikulären Schädigung zeigen.

Bei asymptomatischer primärer Mitralklappeninsuffizienz (MI) kann die chirurgische Mitralklappenrekonstruktion bereits vor dem Auftreten einer linksventrikulären Dilatation oder anderweitigen Folgeschäden erwogen werden, falls mit einer hohen Rekonstruktionswahrscheinlichkeit zu rechnen ist.

Late plasma exosome microRNA-21-5p depicts magnitude of reverse ventricular remodeling after early surgical repair of primary mitral valve regurgitation

Introduction

Primary mitral valve regurgitation (MR) results from degeneration of mitral valve apparatus. Mechanisms leading to incomplete postoperative left ventricular (LV) reverse remodeling (Rev-Rem) despite timely and successful surgical mitral valve repair (MVR) remain unknown. Plasma exosomes (pEXOs) are smallest nanovesicles exerting early postoperative cardioprotection. We hypothesized that late plasma exosomal microRNAs (miRs) contribute to Rev-Rem during the late postoperative period.

Methods

Primary MR patients (n = 19; age, 45-71 years) underwent cardiac magnetic resonance imaging and blood sampling before (T0) and 6 months after (T1) MVR. The postoperative LV Rev-Rem was assessed in terms of a decrease in LV end-diastolic volume and patients were stratified into high (HiR-REM) and low (LoR-REM) LV Rev-Rem subgroups. Isolated pEXOs were quantified by nanoparticle tracking analysis. Exosomal microRNA (miR)-1, -21-5p, -133a, and -208a levels were measured by RT-qPCR. Anti-hypertrophic effects of pEXOs were tested in HL-1 cardiomyocytes cultured with angiotensin II (AngII, 1 μM for 48 h).

Results

Surgery zeroed out volume regurgitation in all patients. Although preoperative pEXOs were similar in both groups, pEXO levels increased after MVR in HiR-REM patients (+0.75-fold, p = 0.016), who showed lower cardiac mass index (-11%, p = 0.032). Postoperative exosomal miR-21-5p values of HiR-REM patients were higher than other groups (p < 0.05). In vitro, T1-pEXOs isolated from LoR-REM patients boosted the AngII-induced cardiomyocyte hypertrophy, but not postoperative exosomes of HiR-REM. This adaptive effect was counteracted by miR-21-5p inhibition.

Summary/Conclusion

High levels of miR-21-5p-enriched pEXOs during the late postoperative period depict higher LV Rev-Rem after MVR. miR-21-5p-enriched pEXOs may be helpful to predict and to treat incomplete LV Rev-Rem after successful early surgical MVR.

Myocardial fibrosis in asymptomatic patients undergoing surgery for mitral and aortic valve regurgitation

BACKGROUND

Chronic heart valve regurgitation induces left ventricular (LV) volume overload, leading to the development of hypertrophy and progressive dilatation of the ventricle to maintain physiological cardiac output. In order to prevent potential irreversible LV structural changes, the identification of the best timing for treatment is pivotal.

OBJECTIVE

To assess the presence and extent of fibrosis in myocardial tissue in asymptomatic patients with valvular heart disease (VHD) and preserved LV dimensions and function undergoing cardiac surgery.

METHODS

Thirty-nine patients were enrolled. Sixteen patients were affected by aortic or mitral regurgitation: they were all asymptomatic, undergoing valve surgery according to VHD European Society of Cardiology guidelines. Twenty-three patients with end-stage nonischemic dilated cardiomyopathy (DCM) and severe LV dysfunction undergoing cardiac surgery for implantation of a durable left ventricular assist device (LVAD) served as controls. During surgery, VHD patients underwent three myocardial biopsies at the level of the septum, the lateral wall and LV apex, while in LVAD patients the coring of the apex of the LV was used. For both groups, the tissue samples were analyzed on one section corresponding to the apical area. All slides were stained with hematoxylin and eosin and Masson's trichrome staining and further digitalized. The degree of fibrosis was then calculated as a percentage of the total area.

RESULTS

Of 39 patients, 23 met the inclusion criteria: 12 had mitral or aortic insufficiency with a preserved ejection fraction and 11 had idiopathic dilated cardiomyopathy. Quantitative analysis of apical sections revealed a myocardial fibrosis amount of 10 ± 6% in VHD patients, while in LVAD patients the mean apical myocardial fibrosis rate was 38 ± 9%. In VHD patients, fibrosis was also present in the lateral wall (9 ± 4%) and in the septum (9 ± 6%).

CONCLUSION

Our case series study highlights the presence of tissue remodeling with fibrosis in asymptomatic patients with VHD and preserved LV function. According to our results, myocardial fibrosis is present at an early stage of the disease, well before developing detectable LV dysfunction and symptoms. Since the relationship between the progressive magnitude of myocardial fibrosis and potential prognostic implications are not yet defined, further studies on this topic are warranted.

Cardiorenal Syndrome: An Updated Classification Based on Clinical Hallmarks

Cardiorenal syndrome (CRS) is defined as progressive, combined cardiac and renal dysfunction. In this mini review, a historical note on CRS is presented, the pathomechanisms and clinical hallmarks of both chronic heart failure and chronic kidney disease are discussed, and an updated classification of CRS is proposed. The current consensus classification relies on the assumed etiology and the course of the disease, i.e., acute or chronic CRS. Five types are described: type-I CRS presenting as acute cardiac failure leading to acute renal failure; type-II CRS presenting as chronic cardiac failure leading to chronic renal failure; type-III CRS presenting as acute kidney injury aggravating heart failure; type-IV CRS presenting as chronic kidney failure aggravating heart failure; and type-V CRS presenting as concurrent, chronic cardiac and renal failure. For an updated classification, information on the presence or absence of valvular heart disease and on the presence of hyper- or hypovolemia is added. Thus, CRS is specified as “acute” (type-I, type-III or type-V CRS) or “chronic” (type-II, type-IV or type-V) CRS, as “valvular” or “nonvalvular” CRS, and as “hyper-” or “hypovolemia-associated” CRS if euvolemia is absent. To enable the use of this updated classification, validation studies are mandated.

Cardiac Damage Staging Classification in Asymptomatic Moderate or Severe Primary Mitral Regurgitation

Background

Optimal timing for intervention remains uncertain in asymptomatic patients with primary mitral regurgitation (MR). We aimed to assess the prognostic value of a new cardiac damage staging classification in patients with asymptomatic moderate or severe primary MR.

Methods

Clinical, Doppler-echocardiographic, and outcome data prospectively collected in 338 asymptomatic patients (64 ± 15 years, 68% men) with at least moderate primary MR were retrospectively analyzed. Patients were hierarchically classified as per the following staging classification: no cardiac damage (stage 0), mild left ventricular or left atrial damage (stage 1), moderate or severe left ventricular or left atrial damage (stage 2), pulmonary vasculature or tricuspid valve damage (stage 3), or right ventricular damage (stage 4).

Results

There was a stepwise increase in 10-year mortality rates as per cardiac damage stage: 20.0% in stage 0, 25.6% in stage 1, 31.5% in stage 2, and 61.3% in stage 3-4 (p < 0.001). The staging classification was significantly associated with increased risk of mortality (hazard ratio = 1.41 per one-stage increase, 95% confidence interval: 1.07-1.85, p = 0.015) and the composite of cardiovascular mortality or hospitalization (hazard ratio = 1.51 per one-stage increase, 95% confidence interval: 1.07-2.15, p = 0.020) in multivariable analysis adjusted for EuroSCORE II, mitral valve intervention as a time-dependent variable, and other risk factors. The proposed scheme showed incremental value over several clinical variables (net reclassification index = 0.40, p = 0.03).

Conclusions

The new staging classification provides independent and incremental prognostic value in patients with asymptomatic moderate or severe MR.

Prognostic value of left atrial reservoir function in patients with severe primary mitral regurgitation undergoing mitral valve repair

AIMS

Mitral regurgitation (MR) has a significant haemodynamic impact on the left atrium. Assessment of left atrial reservoir strain (LARS) may have important prognostic implications, incremental to left atrial (LA) volume, and conventional parameters of left ventricular (LV) structure and function. This study investigated whether preoperative assessment of LARS by speckle tracking echocardiography is associated with long-term outcomes in patients undergoing mitral valve repair for severe primary MR.

METHODS AND RESULTS

Echocardiography was performed prior to mitral valve surgery in 566 patients (age 64 ± 12years, 66% men) with severe primary MR. The study population was subdivided based on a LARS value of 22%, using a spline curve analysis. The primary endpoint was all-cause mortality. During a median follow-up of 7 (4-12) years, 129 (22.8%) patients died. Patients with LARS ≤22% showed significantly higher mortality rates at 1-, 3-, and 5-year follow-up (6%, 12%, and 15%, respectively) when compared with patients with LARS >22% (2%, 3% and 5%, respectively, P < 0.001). Age [hazard ratio (HR): 1.06; 95% confidence interval (CI): 1.03-1.09; P < 0.001], LV global longitudinal strain (HR: 0.92; 95% CI: 0.87-0.98; P = 0.014), and LARS (HR: 0.96; 95% CI: 0.93-0.99; P = 0.014) were independently associated with all-cause mortality.

CONCLUSION

Preoperative LARS is independently associated with all-cause mortality in patients undergoing mitral valve repair for primary MR and provides incremental prognostic value over LA volume. LARS might be helpful to guide timing of mitral valve surgery in patients with severe primary MR.

Valvular regurgitation flow jet assessment using in vitro 4D flow MRI: Implication for mitral regurgitation

PURPOSE

The purpose of this study was to evaluate the accuracy of four-dimensional (4D) flow MRI for direct assessment of peak velocity, flow volume, and momentum of a mitral regurgitation (MR) flow jets using an in vitro pulsatile jet flow phantom. We systematically investigated the impact of spatial resolution and quantification location along the jet on flow quantities with Doppler ultrasound as a reference for peak velocity.

METHODS

Four-dimensional flow MRI data of a pulsatile jet through a circular, elliptical, and 3D-printed patient-specific MR orifice model was acquired with varying spatial resolution (1.5-5 mm isotropic voxel). Flow rate and momentum of the jet were quantified at various axial distances (x = 0-50 mm) and integrated over time to calculate Vol_jet and MTI_jet . In vivo assessment of Vol_jet and MTI_jet was performed on 3 MR patients.

RESULTS

Peak velocities were comparable to Doppler ultrasound (3% error, 1.5 mm voxel), but underestimated with decreasing spatial resolution (-40% error, 5 mm voxel). Vol_jet was similar to regurgitant volume (RVol) within 5 mm, and then increased linearly with the axial distance (19%/cm) because of flow entrainment. MTI_jet remained steady throughout the jet (2%/cm) as theoretically predicted. Four and 9 voxels across the jet were required to measure flow volume and momentum-time-integral within 10% error, respectively.

CONCLUSION

Four-dimensional flow MRI detected accurate peak velocity, flow rate, and momentum for in vitro MR-mimicking flow jets. Spatial resolution significantly impacted flow quantitation, which otherwise followed predictions of flow entrainment and momentum conservation. This study provides important preliminary information for accurate in vivo MR assessment using 4D flow MRI.

Relation of Guideline Adherence to Outcomes in Patients With Asymptomatic Severe Primary Mitral Regurgitation

Current guidelines empirically recommend serial clinical evaluations for asymptomatic patients with severe mitral regurgitation (MR). However, there is a paucity of data on the effectiveness of such monitoring. This study sought to examine the potential benefit of guideline adherence among asymptomatic patients with severe primary MR. Asymptomatic patients with severe primary MR who had been evaluated in the Allina Health system between January 1, 2012 and May 30, 2018 were examined. The medical records were manually reviewed for demographics, comorbidities, echocardiographic data, subsequent interventions, and clinical outcomes. Patients were grouped according to occurrence of guideline adherence, which was defined as a serial clinical evaluation with echocardiography every 12 ± 1 month until mitral valve surgery, or death. Over the study period, 246 patients (67.3 ± 15.5 years, 61.4% men) with severe, asymptomatic primary MR were identified, including 154 patients (62.6%) with and 92 patients (37.4%) without guideline adherence. Overall, there were no differences in demographics, morbidities, MR severity, or left ventricular function between patient adherence groups. During follow-up (40.9; 21.2, 58.3 months), patients with adherence more frequently had surgery or transcatheter therapy performed (64.3% vs 18.5%; p <0.001) and the time to intervention was earlier (13.6 [3.9-22.7] vs 44.2[25.6-57.3] months; p <0.001). Compared to non-adherent patients, those with guideline adherence had a significantly higher five-year survival free from all-cause mortality (92.0% vs 74.3%, p = 0.002), and freedom from death or hospitalization for heart failure (90.1% vs 69.3%, p = 0.001). Adherent patients also had a significantly better survival free from combined endpoint of death, re-hospitalization for heart failure, myocardial infarction, and stroke (84.5% vs 63.2%, p = 0.002). In patients with asymptomatic severe primary MR, guideline adherence with serial evaluations every 12 months or less is associated with earlier therapy and improved long-term outcomes. These data support educational efforts to promote guideline adherence.

Reverse Myocardial Remodeling Following Valve Repair in Patients With Chronic Severe Primary Degenerative Mitral Regurgitation

OBJECTIVES

The aims of this study were to quantify preoperative myocardial fibrosis using late gadolinium enhancement (LGE), extracellular volume fraction (ECV%), and indexed extracellular volume (iECV) on cardiac magnetic resonance; determine whether this varies following surgery; and examine the impact on postoperative outcomes.

BACKGROUND

Myocardial fibrosis complicates chronic severe primary mitral regurgitation and is associated with left ventricular dilatation and dysfunction. It is not known if this nonischemic fibrosis is reversible following surgery or if it affects ventricular remodeling and patient outcomes.

METHODS

A multicenter prospective study was conducted among 104 subjects with primary mitral regurgitation undergoing mitral valve repair. Cardiac magnetic resonance and cardiopulmonary exercise stress testing were performed preoperatively and ≥6 months after surgery. Symptoms were assessed using the Minnesota Living With Heart Failure Questionnaire.

RESULTS

Mitral valve repair was performed for Class 2a indications in 65 patients and Class 1 indications in 39 patients. Ninety-three patients were followed up at 8.8 months (interquartile range: 7.4 months-10.6 months). Following surgery, there were significant reductions in both ECV% (from 27.4% to 26.6%; P = 0.027) and iECV (from 17.9 to 15.4 mL/m²; P < 0.001), but the incidence of LGE was unchanged. Neither preoperative ECV% nor LGE affected postoperative function, but iECV predicted left ventricular end-systolic volume index (β = 1.04; 95% CI: 0.49 to 1.58; P < 0.001) and left ventricular ejection fraction (β = -0.61; 95% CI: -1.05 to -0.18; P = 0.006). Patients with above-median iECV of ≥17.6 mL/m² had significantly larger postoperative values of left ventricular end-systolic volume index (30.5 ± 12.7 mL/m² vs 23.9 ± 8.0 mL/m²; P = 0.003), an association that remained significant in subcohort analyses of patients in New York Heart Association functional class I.

CONCLUSIONS

Mitral valve surgery results in reductions in ECV% and iECV, which are surrogates of diffuse myocardial fibrosis, and preoperative iECV predicts the degree of postoperative remodeling irrespective of symptoms. (The Role of Myocardial Fibrosis in Degenerative Mitral Regurgitation; NCT02355418).

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

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

Optimizing Timing of Valve Intervention in Patients With Asymptomatic Severe Valvular Heart Disease

The management of valvular heart disease has changed dramatically over the past decade with advances in cardiac imaging, the use of novel biomarkers, and the development of transcatheter valve repair and replacement technology. International society guidelines have kept pace to provide recommendations for diagnosis, follow-up, and timing of intervention. The most challenging patient cohort for clinicians are patients with asymptomatic severe disease in whom the optimal timing of intervention can be ill-defined. It is a fine balance between the risks of early intervention on asymptomatic patients and improving patient outcomes by preventing long-term cardiac complications. The key in optimal patient management is gathering the necessary information on patient risk and combining that with the risk, efficacy, and durability of valve interventions to arrive at the appropriate timing for intervention. This group of patients will be the focus of this review as we delve into the natural history, recommended follow-up, and indications for intervention in patients with degenerative aortic and mitral valve disease.

The current diagnosis and treatment of high-risk patients with chronic primary and secondary mitral valve regurgitation

Mitral valve regurgitation (MR) is due primarily to either primary degeneration of the mitral valve with Barlow's or fibroelastic disease or is secondary to ischemic or nonischemic cardiomyopathies. Echocardiography is essential to assess MR etiology and severity, the remodeling of cardiac chambers and to characterize longitudinal chamber changes to determine optimal therapies. Surgery is recommended for severe primary MR if persistent symptoms are present or if left ventricle dysfunction is present with an EF <60% or a left ventricle end-systolic diameter ≥40 mm. For secondary MR, therapy of heart failure with vasodilators and diuretics improves forward cardiac output. Coronary artery bypass grafts (CABG) or percutaneous coronary intervention (PCI) should be considered for severe MR due to ischemia. This review summarizes the pathophysiology, the characteristics, the management and the different interventions for high risk patients with chronic primary and secondary MR.

Advances in Mitral Valve Repair for Degenerative Mitral Regurgitation: Philosophy, Technical Details, and Long-Term Results

Degenerative mitral valve disease represents the most common cause of mitral regurgitation in industrialized countries. When left untreated, patients with severe degenerative mitral regurgitation show a poor clinical outcome. Conversely, a timely and appropriate correction provides a restored life expectancy and a good quality of life. Therefore, in this scenario, surgical mitral valve repair represents the gold standard of treatment. This review aims to analyze the indications, timing, and contemporary surgical techniques of mitral valve repair for degenerative mitral regurgitation. Moreover, the value of heart team approach and centers of excellence for mitral valve repair are also deeply discussed.

Current status of the treatment of degenerative mitral valve regurgitation

Degenerative mitral valve disease (myxomatous degeneration or fibroelastic deficiency) is the most common indication for surgical referral to treat mitral regurgitation. Mitral valve repair is the procedure of choice whenever feasible and when the results are expected to be durable. Posterior leaflet prolapse is the commonest lesion, found in up to two-thirds of patients. It is the easiest to repair, particularly when limited to one segment. In these cases, rates of repairability and procedural success approach 100%, and there is now ample evidence that the immediate and long-term results are better than those of valve replacement. Notably, minimally invasive valvular procedures, surgical or interventional, have attracted increasing interest in the last decade. When performed by experienced groups, mitral valve repair is unrivaled irrespective of the severity of lesions, from simple to complex, which leaflets are involved, and the type of degenerative involvement (myxomatous or fibroelastic). Its results should be viewed as the benchmark for other present and future technologies. By contrast, percutaneous mitral valve repair is still in its infancy and its results so far fall short of those of surgical repair. Nevertheless, continued investment in transcatheter procedures is of great importance to enable development and improved accessibility, particularly for patients who are considered unsuitable for surgery. In this review, we analyze the current status of management of degenerative mitral valve disease, discussing mitral valve anatomy and pathology, indications for intervention, and current surgical and transcatheter mitral valve procedures and results.

Hemodynamic and transcriptomic studies suggest early left ventricular dysfunction in a preclinical model of severe mitral regurgitation

OBJECTIVE

Primary mitral regurgitation is a valvular lesion in which the left ventricular ejection fraction remains preserved for long periods, delaying a clinical trigger for mitral valve intervention. In this study, we sought to investigate whether adverse left ventricular remodeling occurs before a significant fall in ejection fraction and characterize these changes.

METHODS

Sixty-five rats were induced with severe mitral regurgitation by puncturing the mitral valve leaflet with a 23-G needle using ultrasound guidance. Rats underwent longitudinal cardiac echocardiography at biweekly intervals and hearts explanted at 2 weeks (n = 15), 10 weeks (n = 15), 20 weeks (n = 15), and 40 weeks (n = 15). Sixty age- and weight-matched healthy rats were used as controls. Unbiased RNA-sequencing was performed at each terminal point.

RESULTS

Regurgitant fraction was 40.99 ± 9.40%, with pulmonary flow reversal in the experimental group, and none in the control group. Significant fall in ejection fraction occurred at 14 weeks after mitral regurgitation induction. However, before 14 weeks, end-diastolic volume increased by 93.69 ± 52.38% (P < .0001 compared with baseline), end-systolic volume increased by 118.33 ± 47.54% (P < .0001 compared with baseline), and several load-independent pump function indices were reduced. Transcriptomic data at 2 and 10 weeks before fall in ejection fraction indicated up-regulation of myocyte remodeling and oxidative stress pathways, whereas those at 20 and 40 weeks indicated extracellular matrix remodeling.

CONCLUSIONS

In this rodent model of mitral regurgitation, left ventricular ejection fraction was preserved for a long duration, yet rapid and severe left ventricular dilatation, and biological remodeling occurred before a clinically significant fall in ejection fraction.

2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the valvular heart disease guideline provides recommendations for clinicians to diagnose and manage valvular heart disease as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to March 1, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, Cochrane, Agency for Healthcare Research and Quality Reports, and other selected database relevant to this guideline. Structure: Many recommendations from the earlier valvular heart disease guidelines have been updated with new evidence and provides newer options for diagnosis and treatment of valvular heart disease. This summary includes only the recommendations from the full guideline which focus on diagnostic work-up, the timing and choice of surgical and catheter interventions, and recommendations for medical therapy. The reader is referred to the full guideline for graphical flow charts, text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in developing these guidelines.

Echocardiographic predictors of exercise induced pulmonary hypertension in patients with asymptomatic moderate to severe mitral regurgitation and preserved left ventricular ejection fraction

BACKGROUND

The significant role of mitral regurgitation (MR) in development of pulmonary hypertension (PH) has been proved in previous studies. Experts suggest systolic pulmonary arterial pressure (SPAP) ⩾60 mmHg during exercise as a significant threshold of negative prognostic value in patients with MR.

PURPOSE

The aim of this study was to evaluate the changes of SPAP and to ascertain the determinants of exercise induced pulmonary hypertension (EIPH) in patients with asymptomatic primary MR.

METHODS

We performed a prospective study that included 50 patients with asymptomatic primary moderate to severe MR with preserved left ventricular ejection fraction (LV EF ⩾60%) at rest. They were divided into two groups according to the presence (PH group; n = 13) or absence (non-PH group; n = 37) of EIPH. Rest and stress (bicycle ergometry) echocardiography and speckle-tracking offline analysis were performed.

RESULTS

An increment of SPAP from rest to peak stress was higher in PH group (p < 0.001). Multivariate regression analysis showed that MR effective regurgitation orifice area (EROA; p = 0.008) and regurgitant volume (RVol; p = 0.006) contributed significantly to SPAP at rest. Higher increment of MR EROA during stress and worse parameters of LV diastolic function at rest (E, A, E/e') correlated significantly with higher SPAP during peak stress and they had a major role in predicting EIPH according to univariate logistic regression analysis. In ROC analysis SPAP >33.1 mmHg at rest could predict EIPH with 84.6% sensitivity and 87.1% specificity (95%CI 0.849-1.000; p < 0.001).

CONCLUSIONS

Parameters of MR severity (EROA and RVol) were significant determinants of SPAP at rest, while the increment of MR EROA during stress and parameters of resting LV diastolic function were the best predictors of significant EIPH.

Novelties in 3D Transthoracic Echocardiography

Cardiovascular imaging is developing at a rapid pace and the newer modalities, in particular three-dimensional echocardiography, allow better analysis of heart structures. Identifying valve lesions and grading their severity represents crucial information and nowadays is strengthened by the introduction of new software, such as transillumination, which provide detailed morphology descriptions. Chambers quantification has never been so rapid and accurate: machine learning algorithms generate automated volume measurements, including left ventricular systolic and diastolic function, which is extremely important for clinical decisions. This review provides an overview of the latest innovations in the echocardiography field, and is helpful by providing a better insight into heart diseases.

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

AIMS

To define the hitherto unknown aetiology/mechanism distributions of mitral regurgitation (MR) in the community and the linked clinical characteristics/outcomes.

METHODS AND RESULTS

We identified all isolated, moderate/severe MR diagnosed in our community (Olmsted County, MN, USA) between 2000 and 2010 and classified MR aetiology/mechanisms. Eligible patients (n = 727) were 73 ± 18 years, 51% females, with ejection fraction (EF) 49 ± 17%. MR was functional (FMR) in 65%, organic (OMR) in 32% and 2% mixed. Functional MR was linked to left ventricular remodelling (FMR-v) 38% and isolated atrial dilatation (FMR-a) 27%. At diagnosis FMR-v vs. FMR-a, vs. OMR displayed profound differences (all P < 0.0001) in age (73 ± 14, 80 ± 10, 68 ± 21years), male-sex (59, 33, 51%), atrial-fibrillation (28, 54, 13%), EF (33 ± 14, 57 ± 11, 61 ± 10%), and regurgitant-volume (38 ± 13, 37 ± 11, 51 ± 24 mL/beat). Dominant MR mechanism was Type I (normal valve-movement) 38%, Type II (excessive valve-movement) 25%, Type IIIa (diastolic movement-restriction) 3%, and Type IIIb (systolic movement-restriction) 34%. Outcomes were mediocre with excess-mortality vs. general-population in FMR-v [risk ratio 3.45 (2.98-3.99), P < 0.0001] but also FMR-a [risk ratio 1.88 (1.52-2.25), P < 0.0001] and OMR [risk ratio 1.83 (1.50-2.22), P < 0.0001]. Heart failure was frequent, particularly in FMR-v (5-year 83 ± 3% vs. 59 ± 4% FMR-a, 40 ± 3% OMR, P < 0.0001). Mitral surgery during patients' lifetime was performed in 4% of FMR-v, 3% of FMR-a, and 37% of OMR.

CONCLUSION

Moderate/severe isolated MR in the community displays considerable aetiology/mechanism heterogeneity. Functional MR dominates, mostly FMR-v but FMR-a is frequent and degenerative MR dominates OMR. Outcomes are mediocre with excess-mortality particularly with FMR-v but FMR-a, despite normal EF incurs notable excess-mortality and frequent heart failure. Pervasive undertreatment warrants clinical trials of therapies tailored to specific MR cause/mechanisms.

The most influential papers in mitral valve surgery; a bibliometric analysis

This study is an analysis of the 100 most cited articles in mitral valve surgery. A bibliometric analysis is a tool to evaluate research performance in a given field. It uses the number of times a publication is cited by others as a proxy marker of its impact. The most cited paper Carpentier et al. discusses mitral valve repair in terms of restoring the geometry of the entire valve rather than simply narrowing the annulus (Carpentier, J Thorac Cardiovasc Surg 86:23–37, 1983). The first successful mitral valve repair was performed by Elliot Cutler at Brigham and Women’s Hospital in 1923 (Cohn et al., Ann Cardiothorac Surg 4:315, 2015). More recently percutaneous and minimally invasive techniques that were originally designed as an option for high risk patients are being trialled in other patient groups (Hajar, Heart Views 19:160–3, 2018). Comparison of percutaneous method with open repair represents an expanding area of research (Hajar, Heart Views 19:160–3, 2018). This study will analyse the top 100 cited papers relevant to mitral valve surgery, identifying the most influential papers that guide current management, the institutions that produce them and the authors involved.