Long-term survival in asymptomatic patients with severe degenerative mitral regurgitation: A propensity score–based comparison between an early surgical strategy and a conservative treatment approach

Pulmonary arterial compliance as a measure of right ventricular loading in mitral regurgitation

Pulmonary hypertension (PH) is a common and prognostically important complication of mitral regurgitation (MR). Mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) are traditionally used to diagnose PH, however these indices measure static rather than pulsatile load, leading to an incomplete representation of pulmonary vascular load on the right ventricle (RV). Pulmonary arterial compliance (PAC) is one method for quantifying pulsatile load, and is both a stronger predictor of prognosis in left heart failure, as well as a more sensitive measure of early pulmonary vascular dysfunction than PVR. With the expansion of transcatheter mitral and tricuspid valve therapies, there is renewed interest to more accurately define the load imposed by the pulmonary vasculature on the RV, especially in the early phase, prior to the onset of chronic PH. This review discusses the pathophysiology of pH in left heart failure and MR, the utility of PAC as a measure of RV afterload, and its calculation for clinical use and interpretation, underlining the utility of PAC as an adjunct for assessing pulmonary vascular haemodynamics.

Prevalence of asymptomatic valvular heart disease in the elderly population: a community-based echocardiographic study

AIMS

With an ageing population, the presence of asymptomatic valvular heart disease (VHD) in the community remains unknown. The aim of this study is to determine the prevalence and associated factors of asymptomatic VHD in individuals ≥60 years old and to evaluate the feasibility of echocardiographic screening for VHD in this population.

METHODS AND RESULTS

This was a prospective cohort study conducted between 2007 and 2016 in the UK. Asymptomatic patients with no prior indication for echocardiography were invited to participate and evaluated with a health questionnaire, clinical examination, and transthoracic echocardiography. A total of 10,000 individuals were invited through their general practices. A total of 5429 volunteered to participate, of whom 4237 were eligible for inclusion. VHD was diagnosed in more than a quarter of patients (28.2%). The most common types of VHD were regurgitation of the tricuspid (13.8%), mitral (12.8%), and aortic (8.3%) valves (trivial regurgitation was not included). The rate of prevalence of clinically significant VHD was 2.4% (2.2% moderate and 0.2% severe), with mitral and aortic regurgitation being the most common. The only parameter associated with significant VHD was age (odds ratio 1.07 per 1 year increment, 95% confidence interval 1.05-1.09, P < 0.001). The number needed to scan to diagnose one clinically significant case of VHD is 42 for individuals ≥60 and 15 for those ≥75 years old.

CONCLUSION

Asymptomatic VHD is present in a significant proportion of otherwise healthy individuals without known VHD over 60 years old. Age is strongly associated with an increased incidence of significant VHD.

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.

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.

Mitral Valve Transcatheter Edge-to-Edge Repair Volumes and Trends

Background

Despite an association between operator volumes and procedural success, there remains an incomplete understanding of the contemporary utilization and procedural volumes for mitral valve transcatheter edge-to-edge repair (MTEER). We aimed to identify annual operator procedural volumes, temporal trends, and geographic variability for MTEER among Medicare patients in the United States (US).

Methods

We queried the National Medicare Provider Utilization and Payment Database for a CPT code (33418) specific for MitraClip device from 2015 through 2019. We analyzed annual operator procedural volumes and incidence and identified longitudinal and geographic trends in MTEER utilization.

Results

From 2015 through 2019, a total of 27,034 MTEER procedures were performed among Medicare patients in the US. The nationwide incidence increased from 6.2 per 100,000 patients in 2015 to 23.8 per 100,000 patients in 2019, a 283% increase over the study period (Ptrend < 0.001). The incidence of MTEER by state varied by nearly 900% (range 5.5 to 54.9 per 100,000 person-years). In 2019, the mean annual MTEER operator annual volume was 9.1 MTEER procedures and had grown from 6.2 per year in 2015.

Conclusions

In this nationwide study of Medicare beneficiaries in the United States, we identified a significant and sustained increase in the utilization of MTEER devices and operators and growth in annual procedural volumes from 2015 through 2019 with considerable variability in utilization by state. Further studies are needed to understand the clinical impact of variability in utilization and the optimal procedural volumes to ensure high efficacy outcomes and maintain critical access to MTEER therapies.

Prognostic value of forward flow indices in primary mitral regurgitation due to mitral valve prolapse

Background

Degenerative mitral regurgitation (DMR) due to mitral valve prolapse (MVP) is a common valve disease associated with significant morbidity and mortality. Timing for surgery is debated for asymptomatic patients without Class I indication, prompting the search for novel parameters of early left ventricular (LV) systolic dysfunction.

Aims

To evaluate the prognostic impact of preoperative forward flow indices on the occurrence of post-operative LV systolic dysfunction.

Methods

We retrospectively included all consecutive patients with severe DMR due to MVP who underwent mitral valve repair between 2014 and 2019. LVOTTVI, forward stroke volume index, and forward LVEF were assessed as potential risk factors for LVEF <50% at 6 months post-operatively.

Results

A total of 198 patients were included: 154 patients (78%) were asymptomatic, and 46 patients (23%) had hypertension. The mean preoperative LVEF was 69 ± 9%. 35 patients (18%) had LVEF ≤ 60%, and 61 patients (31%) had LVESD ≥40 mm. The mean post-operative LVEF was 59 ± 9%, and 21 patients (11%) had post-operative LVEF<50%. Based on multivariable analysis, LVOTTVI was the strongest independent predictor of post-operative LV dysfunction after adjustment for age, sex, symptoms, LVEF, LV end systolic diameter, atrial fibrillation and left atrial volume index (0.75 [0.62-0.91], p < 0.01). The best sensitivity (81%) and specificity (63%) was obtained with LVOTTVI ≤15 cm based on ROC curve analysis.

Conclusion

LVOTTVI represents an independent marker of myocardial performance impairment in the presence of severe DMR. LVOTTVI could be an earlier marker than traditional echo parameters and aids in the optimization of the timing of surgery.

Multi-center retrospective cohort study applying deep learning to electrocardiograms to identify left heart valvular dysfunction

BACKGROUND

Aortic Stenosis and Mitral Regurgitation are common valvular conditions representing a hidden burden of disease within the population. The aim of this study was to develop and validate deep learning-based screening and diagnostic tools that can help guide clinical decision making.

METHODS

In this multi-center retrospective cohort study, we acquired Transthoracic Echocardiogram reports from five Mount Sinai hospitals within New York City representing a demographically diverse cohort of patients. We developed a Natural Language Processing pipeline to extract ground-truth labels about valvular status and paired these to Electrocardiograms (ECGs). We developed and externally validated deep learning models capable of detecting valvular disease, in addition to considering scenarios of clinical deployment.

RESULTS

We use 617,338 ECGs paired to transthoracic echocardiograms from 123,096 patients to develop a deep learning model for detection of Mitral Regurgitation. Area Under Receiver Operating Characteristic curve (AUROC) is 0.88 (95% CI:0.88-0.89) in internal testing, and 0.81 (95% CI:0.80-0.82) in external validation. To develop a model for detection of Aortic Stenosis, we use 617,338 Echo-ECG pairs for 128,628 patients. AUROC is 0.89 (95% CI: 0.88-0.89) in internal testing, going to 0.86 (95% CI: 0.85-0.87) in external validation. The model's performance increases leading up to the time of the diagnostic echo, and it performs well in validation against requirement of Transcatheter Aortic Valve Replacement procedures.

CONCLUSIONS

Deep learning based tools can increase the amount of information extracted from ubiquitous investigations such as the ECG. Such tools are inexpensive, can help in earlier disease detection, and potentially improve prognosis.

3D echocardiography in mitral valve prolapse

Mitral valve prolapse (MVP) is the leading cause of mitral valve surgery. Echocardiography is the principal imaging modality used to diagnose MVP, assess the mitral valve morphology and mitral annulus dynamics, and quantify mitral regurgitation. Three-dimensional (3D) echocardiographic (3DE) imaging represents a consistent innovation in cardiovascular ultrasound in the last decades, and it has been implemented in routine clinical practice for the evaluation of mitral valve diseases. The focus of this review is the role and the advantages of 3DE in the comprehensive evaluation of MVP, intraoperative and intraprocedural monitoring.

A journey from resect to respect to restore: aiming at optimal physiological surgical mitral valve repair

The concept of 'repairing' a degenerated mitral valve in order to restore the native competence means achieving the best physiological result coupled with the least invasive approach: this represents an interesting challenge for cardiac surgeons. The evolution of cardiac surgery through the years has involved techniques and technologies in every field of interest. From 'resect', to 'respect', to 'restore': the micro-invasive approach based on Neochord implant implies a transapical beating heart surgery which is based on the concept of implanting artificial chordae, preserving the physiological dynamics of the mitral annulus and avoiding the disadvantages of cardiopulmonary bypass and cardioplegic arrest of the heart.

Frequency, predictors and cardiovascular outcomes associated with transthoracic echocardiographic findings during acute ischaemic stroke hospitalisation

OBJECTIVE

To characterise the clinical utility of transthoracic echocardiography (TTE) at the time of acute ischaemic stroke (AIS).

BACKGROUND

The utility of obtaining a TTE during AIS hospitalisation is uncertain.

METHODS

We studied AIS hospitalisations at a single centre (2002-2016). TTE abnormalities were classified as findings associated with: high stroke risk (Category I), cardiac events (Category II) and of unclear significance (Category III). We performed logistic regressions to predict Category I, II and III abnormalities. The odds of 1 year recurrent stroke hospitalisation captured by ICD 9 and 10 codes as a function of Category I, II and III abnormalities were assessed. Improvement in predictive capacity for 1 year recurrent ischaemic stroke hospitalisation beyond stroke risk factors was evaluated by net reclassification improvement.

RESULTS

There were 5523 AIS hospitalisations. Nearly 81% of admission TTEs were abnormal (18.7% Category I, 32.7% Category II, 72.8% Category III). Older patients with coronary artery disease, atrial fibrillation, hypertension, diabetes, and patent intracranial and extracranial vessels were likely to have an abnormal TTE. Category I finding was associated with lower odds of 1-year recurrent stroke hospitalisation (OR 0.54, 95% CI 0.30 to 0.96). Category I data significantly improved the predictive value for 1-year recurrent ischaemic stroke hospitalisation beyond stroke risk factors (net reclassification improvement 0.1563, 95% CI 0.0465 to 0.2661).

CONCLUSIONS

TTE abnormalities associated with stroke and cardiac event risk were commonly detected during AIS hospitalisation. Detection of Category I TTE findings reduced the risk of recurrent stroke, potentially due to neutralisation of the cardioembolic source by targeted therapy, indicating the clinical utility of TTE.

Relative Impact of Surgical Mitral Repair and MitraClip on Annular Remodeling-A Potential Mechanism for Therapeutic Response to Mitral Repair for Degenerative Mitral Regurgitation

OBJECTIVES

Three-dimensional transesophageal echocardiography (TEE) is widely used to guide decision-making for mitral repair. The relative impact of surgical mitral valve repair (MVr) and MitraClip on annular remodeling is unknown. The aim was to determine the impact of both mitral repair strategies on annular geometry, including the primary outcome of annular circumference and area.

DESIGN

This was a retrospective observational study of patients who underwent mitral intervention between 2016 and 2020.

SETTING

Weill Cornell Medicine, a single, large, academic medical center.

PARTICIPANTS

The population comprised 50 patients with degenerative mitral regurgitation (MR) undergoing MVr.

INTERVENTIONS

Elective MVr and TEE.

MEASUREMENTS AND MAIN RESULTS

Patients undergoing MitraClip or surgical MVr were matched (1:1) for sex and coronary artery disease. Mitral annular geometry indices were quantified on intraprocedural three-dimensional TEE. Mild or less MR on follow-up transthoracic echocardiography defined optimal response. Patients undergoing MitraClip were older (80 ± eight v 66 ± six years; p < 0.001) but were otherwise similar to surgical patients. Patients undergoing MitraClip had larger baseline left atrial and ventricular sizes, increased tenting height, and volume (p < 0.01), with a trend toward increased annular area (p = 0.23). MitraClip and surgery both induced immediate mitral annular remodeling, including decreased area, circumference, and tenting height (p < 0.001), with greater remodeling with surgical repair. At follow-up (4.1 ± 9.0 months) optimal response (≤ mild MR) was ∼twofold more common with surgery than MitraClip (81% v 46%; p = 0.02). The relative reduction in annular circumference (odds ratio [OR] 1.05 [1.00-1.09] per cm; p = 0.04) and area (OR 1.03 [1.00-1.05] per cm2; p = 0.049) were both associated with optimal response.

CONCLUSIONS

Surgical MVr and MitraClip both reduce annular size, but repair-induced remodeling is greater with surgery and associated with an increased likelihood of optimal response.

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.

Clinical Features and Outcomes in Adults With Childhood Repair of Partial Atrioventricular Septal Defect

Background

Partial atrioventricular septal defects (pAVSDs) are mostly repaired in childhood; however, there are limited data describing these patients in adulthood.

Objectives

The objective of this study was to describe clinical course and associations with outcomes in adults with repaired pAVSDs.

Methods

A retrospective review of adults (≥18 years) with pAVSDs repaired in childhood who presented to the Adult Congenital Heart Disease Clinic at our institution was conducted.

Results

Of 121 patients, the median age was 31 years (IQR: 22-43 years) and 71.9% were female. The median number of operations at the time of presentation was 1 (IQR: 1-2). Left atrioventricular valve (LAVV) replacement had been performed in 19.8% of patients. Among those with native LAVV, 41.2% had ≥ moderate regurgitation. Atrial arrhythmias were present in 34.7% and were associated with later age at repair (P = 0.02) and a high number of prior surgeries (P = 0.005). Estimated systolic pulmonary artery pressure >40 mmHg was seen in 19.8%. Over 4 (IQR: 1-12) years of follow-up, death occurred in 13 (10.7%) patients and reoperation was required in 39.7%. One-third had a LAVV prosthesis by the end of the study. Atrial fibrillation was independently associated with death or hospitalization on multivariable analysis.

Conclusions

In this cohort of adults with pAVSDs repaired in childhood, atrial fibrillation was common at a young age and associated with worse outcomes. Thus, more studies are needed evaluating the cause of this arrhythmia burden and possible associated atrial myopathy. While many require surgery in adulthood, more information is needed regarding indications for and impacts of LAVV intervention as one-third had an LAVV prosthesis by the end of follow-up.

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.

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.

Economic Analysis and Long-term Follow-up of Distant Referral for Degenerative Mitral Valve Repair

BACKGROUND

Despite the superiority of mitral valve repair (MVr) over replacement for degenerative disease, repair rates vary widely across centers. Traveling to a mitral reference center (MRC) is 1 way to increase the odds of MVr. This study assessed the economic value (quality/cost) and long-term outcomes of distant referral to an MRC.

METHODS

Among 746 mitral surgery patients between January 2011 and June 2013, low-risk patients with an ejection fraction greater than 40% undergoing isolated degenerative MVr were identified and included 26 out-of-state (DISTANT) and 104 in-state patients (LOCAL). Short- and long-term outcomes and institutional financial data (including travel expenses) were used to compare groups. National average and MRC-specific MVr rates, clinical outcomes, and marginal value of quality-adjusted life-years collected from The Society of Thoracic Surgeons database and Medicare estimates were used to perform a nationally representative cost-benefit analysis for distant referral.

RESULTS

Age, ejection fraction, operative time, blood transfusions, and annuloplasty ring size did not differ between groups. Median charges were $76,022 for LOCAL and $74,171 for DISTANT (P = .35), whereas median payments (including travel expenses) were $57,795 for LOCAL and $58,477 for DISTANT (P = .70). Short- and long-term outcomes were similar between groups and median follow-up was 7.1 years. Estimated 5-year survival was 97% (96% for LOCAL and 100% for DISTANT; P = .24). Cost-benefit analysis showed a net benefit through distant referral to an MRC ranging from $436 to $6078 to the payer and $22,163 to $30,067 to the patient, combining for an estimated $22,599 to $32,528 societal benefit.

CONCLUSIONS

These data suggest that distant referral to an MRC is achievable and reasonable.

New synthetic mitral valve model for human prolapsed mitral valve reconstructive surgery for training

The training process of young surgeons is highly desirable in order for them to gain an understanding of the quality of care and patient safety required during cardiac surgeries, however, it may take a few years of practice in order for them to properly develop these skills. Artificial life-like platforms and models are extremely recommended for teaching hands-on and real-world practice in both junior and even experienced medical professionals and surgeons. Suitable and accessible training tools are of significant importance for simulating a particular surgery in order to provide practice opportunities for a specific surgical procedure. In this study, we focussed on the simulation of the human mitral valve prolapse reconstructive surgery. An innovative, artificial, biomimetic model was designed and fabricated made of Cryogel biomaterial developed in our lab that is suitable for the precise practice on the mitral valve prolapse model. The proposed model is mainly made up of polyvinyl alcohol (PVA) cryogel, which is designed to resemble the geometric and mechanical properties of a diseased (prolapse) mitral valve. We simulated the constructive prolapsed mitral valve surgery entirely on a synthetic platform. The platform was made available to four certified cardiac surgeon and there were unanimously very positive with no considerable differences in the procedural assessments between them. The proposed model has a similar appearance and texture to that of a diseased mitral valve and holds consistent mechanical properties to those of the real tissue. The offered technology may be used for other cardiothoracic reconstructive surgeries with high precision and consistency.

Robotic Mitral Valve Repair: Indication for Surgery Does Not Influence Early Outcomes

OBJECTIVE

To evaluate the outcomes of robotic mitral valve repair (MVr) by primary indication per American Heart Association guidelines for surgery: class I vs class IIa.

PATIENTS AND METHODS

From January 1, 2008, through September 30, 2016, 603 patients underwent robotic MVr for severe primary mitral regurgitation. Medical records of 576 consenting patients were retrospectively reviewed to determine the primary indication for surgery. Patients were stratified into class I or class IIa, and preoperative, intraoperative, and postoperative variables were compared.

RESULTS

Of 516 patients, 428 (83%) had class I indication and 88 (17%) had class IIa indication for surgery. Preoperatively, no significant differences were observed between both cohorts. Importantly, a significantly higher number of patients with class I indication underwent MVr for bileaflet prolapse (172 of 428 [40%] vs 21 of 88 [25%]; P=.03). Early MVr outcomes indicated recurrent mitral regurgitation (moderate or greater) in only 12 of 576 (2%), and no significant differences were observed between classes (P=.23). Apart from parameters for ventricular size, all other intraoperative and postoperative variables were comparable between both cohorts.

CONCLUSION

Comparable outcomes were indicated across all classes of indications for MVr surgery. These results continue to support the use of this surgical technique, even in less sick patients. Early referral along with more extensive robotic MVr experience will likely result in further improvements in long-term outcomes.

Degenerative Mitral Valve Repair Restores Life Expectancy

BACKGROUND

Mitral valve repair (MVr) for severe, degenerative mitral regurgitation is the gold standard, because medical management carries poor prognosis. However, despite clear benefit of MVr, many eligible patients are untreated. This study investigated whether MVr restores patients to normal life expectancy, at any age of operation, by comparing long-term survival of patients after MVr with the life expectancy of the general United States population.

METHODS

This retrospective study investigated 1011 patients with degenerative mitral regurgitation who underwent isolated MVr between 2003 and 2017. Parametric distribution analysis was applied to long-term post-MVr mortality data, and Weibull probability plots provided the best-fit distribution by Anderson-Darling Goodness-of-Fit testing. Confidence intervals of the estimated distribution were used to compare additional life expectancy after MVr to the general US population across multiple decades of life. Patients after MVr were categorized by age into decade (range, 20-89 years).

RESULTS

The life expectancy of patients after MVr matched the life expectancy of the general US population at any age between 40 and 89 years. Lower-bound one-sided 95% confidence intervals for additional life expectancy were not appreciably different from corresponding median additional life expectancy of the general population. There were few deaths in the 20- to 39-year-old group, limiting predictability, but survival also appeared normative.

CONCLUSIONS

These findings suggest that degenerative MVr restores anticipated life expectancy to that of the general population, regardless of age. Although our findings underscore the importance of repair for degenerative mitral disease, larger studies with longer term follow-up are needed to reinforce this finding, particularly for younger patients.

Transthoracic echocardiography in patients undergoing mitral valve repair: comparison of new transthoracic 3D techniques to 2D transoesophageal echocardiography in the localization of mitral valve prolapse

Successful mitral valve (MV) repair for degenerative mitral regurgitation (DMR) is mainly related to surgical expertise and MV anatomy. Although 2D echocardiography, specifically transoesophageal (TOE), provides precise information regarding MV anatomy, recent advancements in matrix technology meant a decisive step forward to the point where segmental MV analysis can be accurately performed from a noninvasive 3D transthoracic (TTE) approach. The aims of this study were: (a) to evaluate the feasibility and time required for real-time 3D TTE in a large consecutive cohort of patients with severe DMR in the assessment of MV anatomy; (b) to compare the accuracy of 3D TTE and 2D TOE versus surgical inspection in the recognition and localization of all components of the MV leaflets; (c) to establish the added diagnostic value of 3D colourDoppler examination to pure 3D morphologic evaluation. 149 consecutive patients with severe DMR underwent complete 3D TTE before surgery and 2D TOE in the operating room. Echocardiographic data obtained by the different techniques were compared with surgical inspection. 3D TTE was feasible in a relatively short time (8 ± 4 min), with good (49%) and optimal (33%) imaging quality in the majority of cases. 3D TTE had significant better overall accuracy compared to 2D TOE (93 and 91%, p < 0.05, respectively). 2D TOE was significantly more specific than 3D TTE in the identification of A3 prolapse (99 vs. 96%). The colourDoppler mode did not improve significantly the accuracy of 3D TTE, albeit it determined a better sensitivity in the detection of A2 prolapse if compared to 2D TOE (95 vs. 85%). 3D TTE with or without colourDoppler is a feasible and useful method in the analysis of MV prolapse; it allows a preoperative and noninvasive description of the pathology as accurate as the 2D TOE.

Primary mitral valve regurgitation: Update and review

Mitral regurgitation is the second most common valvular disorder requiring surgical intervention worldwide. This review summarizes the current understanding of primary, degenerative mitral regurgitation with respect to etiology, comprehensive assessment, natural history and management. The new concept of staging of the valvular disorders, newer predictors of adverse and controversy of “watchful waiting” versus “early surgical intervention” for severe, asymptomatic, primary mitral regurgitation are addressed.

Prognostic Importance of Exercise Brain Natriuretic Peptide in Asymptomatic Chronic Organic Severe Mitral Regurgitation: An Observational Study

BACKGROUND

The optimal timing of surgery in patients with chronic organic severe mitral regurgitation (MR) continues to be debated, especially for those who are asymptomatic. The aim of the study was to determine independent and additive prognostic value of exercise brain natriuretic peptide (eBNP) in patients with severe asymptomatic MR and normal left ventricular ejection fraction (LVEF).

METHODS

Two hundred twenty-three consecutive patients with severe MR defined by effective regurgitant orifice (ERO) area ≥ 40 mm² and/or residual volume ≥ 60 mL, LVEF > 60%, and normal LV end-systolic diameter < 40 mm underwent symptom limited exercise treadmill test (TMT). Echocardiography was done immediately after exercise. Data were obtained within 3 minutes of peak exercise. BNP levels were assessed before echo (after 30 minutes of supine rest) and at exercise (i.e., within the 3 minutes of the end of effort). Patients were followed up every 3 months up to 15 months for major adverse cardiac events (MACEs) (cardiovascular death, need for mitral valve surgery and hospitalization for acute pulmonary edema or heart failure).

RESULTS

Mean age was 31.2 ± 9 years (range: 18 - 40) with majority being male (n = 153; 68%). Etiologies were rheumatic (n = 201; 90%), mitral valve prolapse (n = 17; 7.6%) and hypertrophic cardiomyopathy (n = 5; 2.4%). BNP level significantly increased from rest (65.24 ± 43.92 pg/mL; median: 43.5 pg/mL) to exercise (100.24 ± 98.24 pg/mL; median: 66.5 pg/mL; P < 0.001). Patients were divided into three tertiles according to eBNP levels (T₁ = 15 - 44; T₂ = 45 - 104; T₃ = 105 - 400). There was trend for significantly lower exercise time in T₃. During TMT, 66 (29.5%) stopped exercise due to dyspnea. They had similar resting BNP level compared with others but had significantly higher eBNP level (136 ± 109.7 pg/mL vs. 84.88 ± 90.2 pg/mL; P < 0.001). During follow-up (15 months), MACE occurred in 83 patients (37.2%): mitral valve replacement (MVR) in 59 patients (symptomatic: 43; LV dilatation or dysfunction: 9; both symptoms and dilatation/dysfunction: 7), 17 hospitalizations for congestive heart failure, five patients developing acute pulmonary edema and atrial fibrillation in remaining two patients. This was 7.6%, 35% and 69% in T₁, T₂ and T₃, respectively and had significantly higher eBNP level than without any event (165 ± 119 pg/mL vs. 57 ± 48 pg/mL; P < 0.001). Using receiver operating characteristic curve analysis, the best cut-off value of eBNP level to predict cardiac events was 90 pg/mL (sensitivity: 75%; specificity: 88.6%; positive predictive value: 79%; negative predictive value: 83.9%).

CONCLUSION

In asymptomatic patients, eBNP level provides incremental prognostic value beyond echocardiographic data and those with elevated eBNP should be considered at high risk for reduced event-free survival and might be considered for early MVR.

Mitral valve repair

Mitral regurgitation (MR) is the most common valvular heart disease in the Western world. The MR can be either organic (mainly degenerative in Western countries) or functional (secondary to left ventricular remodeling in the context of ischemic or idiopathic dilated cardiomyopathy). Degenerative and functional MR are completely different disease entities that pose specific decision-making problems and require different management. The natural history of severe degenerative MR is clearly unfavorable. However, timely and effective correction of degenerative MR is associated with a normalization of life expectancy. By contrast, the prognostic impact of the correction of functional MR is still debated and controversial. In this review, we discuss the optimal treatment of both degenerative and functional MR, taking into account current surgical and percutaneous options. In addition, since a clear understanding of the etiology and mechanisms of valvular dysfunction is important to guide the timing and choice of treatment, the role of the heart team and of echo imaging in the management of MR is addressed as well.

Predictors of Late-Onset Atrial Fibrillation Following Isolated Mitral Valve Repairs in Patients With Preserved Ejection Fraction

BACKGROUND

We sought to determine the incidence of and risk factors for late-onset atrial fibrillation (LOAF) in patients with preserved ejection fractions undergoing mitral valve repair

METHODS

We included patients undergoing isolated mitral valve repair (MVR) for degenerative disease between 1997-2014 at our institution with EF ≥60%. Patients who had AF preoperatively were excluded from the final analysis. Our primary outcome, LOAF, was defined as AF occurring after discharge following MVR (≥9 days).

RESULTS

223 patients were included in the study with a mean follow-up of 4.8 ± 4.6 years. A total of 25 patients developed LOAF, and freedom from LOAF was 93.9% at one year, and 87.3% at five years. Patients developing LOAF were of similar mean age (58 vs. 63 years in controls, p = 0.08) and had similar preoperative comorbidities, but did show a trend toward larger left atrial diameter (5.1 vs. 4.7 cm, p = 0.11). After risk adjustment with Cox regression analysis, only increasing left atrial size was associated with LOAF (HR 1.63, p = 0.04). On follow-up, 29 patients (10.8%) developed moderate or greater mitral regurgitation at a mean of 2.2 years. Using a mixed-effects model, we were unable to detect an association between recurrent mitral regurgitation following MVR and LOAF (OR 1.36, p = 0.42).

CONCLUSIONS

LOAF occurs in about 13% of preserved ejection fraction patients undergoing MVR by five years. Increasing left atrial diameter is an independent predictor of LOAF. Concomitant anti-arrhythmic procedures may warrant further investigation in patients with preserved ejection fraction and enlarged left atria undergoing MVR. doi: 10.1111/jocs.12774 (J Card Surg 2016;31:486-492).

Transthoracic Echocardiography Provides Important Long-Term Prognostic Information in Selected Patients Undergoing Endovascular Abdominal Aortic Repair

BACKGROUND

The value of performing transthoracic echocardiography (TTE) as part of the clinical assessment of patients awaiting endovascular repair of the abdominal aorta is little evaluated. We aimed to estimate the prognostic importance of information derived from TTE on long-term all-cause mortality in a selected group of patients undergoing endovascular aneurysm repair.

METHODS AND RESULTS

This was a retrospective cohort study of 273 consecutive patients selected for endovascular aneurysm repair. All patients included in the analysis underwent TTE before their procedure. Multivariable Cox regression analysis was used to estimate the effect of TTE measures on all-cause mortality. Over a mean follow-up of 3.2±1.5 years, there were 78 deaths with a mean time to death of 1.28±1.16 years. A greater tubular ascending aorta (hazard ratio [HR] 5.6, 95% confidence interval [CI] 2.77-11.33), presence of mitral regurgitation (HR 8.13, 95% CI 4.09-12.16), lower left ventricular ejection fraction (HR 0.96, 95% CI 0.93-0.98), younger age (HR 0.97, 95% CI 0.95-0.99), and presence of diabetes mellitus (HR 1.46, 95% CI 1.24-1.89) were predictors of all-cause mortality.

CONCLUSIONS

Echocardiography provides important long-term prognostic information in patients undergoing endovascular aneurysm repair. These TTE indices were more important at predicting outcome than standard conventional risk factors in this patient group. A greater tubular ascending aorta, presence of mitral regurgitation, reduced left ventricular ejection fraction, younger age, and diabetes mellitus were independently associated with long-term mortality.

[Modern mitral valve surgery]

At the beginning of the 20th century, Cutler and Levine performed the first successful surgical treatment of a stenotic mitral valve, which was the only treatable heart valve defect at that time. Mitral valve surgery has evolved significantly since then. The introduction of the heart-lung machine in 1954 not only reduced the surgical risk, but also allowed the treatment of different mitral valve pathologies. Nowadays, mitral valve insufficiency has become the most common underlying pathomechanism of mitral valve disease and can be classified into primary and secondary mitral insufficiency. Primary mitral valve insufficiency is mainly caused by alterations of the valve (leaflets and primary order chords) itself, whereas left ventricular dilatation leading to papillary muscle displacement and leaflet tethering via second order chords is the main underlying pathomechanism for secondary mitral valve regurgitation. Valve reconstruction using the "loop technique" plus annuloplasty is the surgical strategy of choice and normalizes life expectancy in patients with primary mitral regurgitation. In patients with secondary mitral regurgitation, implanting an annuloplasty is not superior to valve replacement and results in high rates of valve re-insufficiency (up to 30 % after 3 months) due to ongoing ventricular dilatation. In order to improve repair results in these patients, we add a novel subvalvular technique (ring-noose-string) to the annuloplasty that aims to prevent ongoing ventricular remodeling and re-insufficiency. In modern mitral surgery, a right lateral thoracotomy is the approach of choice with excellent repair and cosmetic results.

Early surgical intervention or watchful waiting for the management of asymptomatic mitral regurgitation: a systematic review and meta-analysis

BACKGROUND

Discordance between studies drives continued debate regarding the best management of asymptomatic severe mitral regurgitation (MR). The aim of the present study was to conduct a systematic review and meta-analysis of management plans for asymptomatic severe MR, and compare the effectiveness of a strategy of early surgery to watchful waiting.

METHODS

A systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were excluded if they: (I) lacked a watchful waiting cohort; (II) included symptomatic patients; or (III) included etiologies other than degenerative mitral valve disease. The primary outcome of the study was all-cause mortality at 10 years. Secondary outcomes included operative mortality, repair rate, repeat mitral valve surgery, and development of new atrial fibrillation.

RESULTS

Five observational studies were eligible for review and three were included in the pooled analysis. In asymptomatic patients without class I triggers (symptoms or ventricular dysfunction), pooled analysis revealed a significant reduction in long-term mortality with an early surgery approach [hazard ratio (HR) =0.38; 95% confidence interval (CI): 0.21-0.71]. This survival benefit persisted in a sub-group analysis limited to patients without class II triggers (atrial fibrillation or pulmonary hypertension) [relative risk (RR) =0.85; 95% CI: 0.75-0.98]. Aggregate rates of operative mortality did not differ between treatment arms (0.7% vs. 0.7% for early surgery vs. watchful waiting). However, significantly higher repair rates were achieved in the early surgery cohorts (RR =1.10; 95% CI: 1.02-1.18).

CONCLUSIONS

Despite disagreement between individual studies, the present meta-analysis demonstrates that a strategy of early surgery may improve survival and increase the likelihood of mitral valve repair compared with watchful waiting. Early surgery may also benefit patients when instituted prior to the development of class II triggers.

Predictive value of left atrial deformation on prognosis in severe primary mitral regurgitation

BACKGROUND

Impaired left atrial (LA) deformation is noted in patients with severe primary mitral regurgitation (MR), but its prognostic value is unknown. The aim of this study was to investigate the prognostic significance of LA deformation parameters in patients with chronic severe primary MR.

METHODS

A total of 104 patients with asymptomatic chronic severe primary MR (Carpentier type II) and preserved left ventricular systolic function were prospectively recruited. Global peak positive strain of the left atrium (LASp) and strain rate in the LA filling phase (LASRr) as well as strain rate in the LA conduit phase were identified using two-dimensional speckle-tracking echocardiography.

RESULTS

During a mean follow-up period of 13.2 ± 9.5 months, 22 patients reached a composite end point of death and mitral valve repair or replacement prompted by heart failure development. Among the clinical and echocardiographic parameters, LV end-systolic volume index (19.5 ± 9.5 vs 15.7 ± 6.3 mL/m(2), P = .028), LASp (22.7 ± 10.4% vs 27.2 ± 9.1%, P = .049), and LASRr (1.97 ± 0.6 vs 2.33 ± 0.6 1/sec, P = .013) varied between the two groups in terms of end points but not age, LA volume index, left ventricular ejection fraction, pulmonary artery systolic pressure, and presence of atrial fibrillation. After multivariate analysis, low LASp (odds ratio, 3.606; 95% CI, 1.294-10.052; P = .014) and low LASRr (odds ratio, 2.857; 95% CI, 1.078-7.572; P = .035) remained powerful outcome indicators.

CONCLUSIONS

In patients with asymptomatic severe primary MR, reduced LASp and LASRr predicted a worse prognosis. These findings may offer additional information to guide early surgery.

Mitral regurgitation - Unmet need for improved management strategies

Background

The management of mitral regurgitation (MR) is challenging — patients may be asymptomatic, oligosymptomatic, older with comorbidities, or clinically symptomatic and not appropriate for surgery. The current review assesses morbidity, mortality, and risk factors associated with functional and organic MR, with a focus on severe MR.

Methods

A structured literature review was conducted in MEDLINE, Embase, the Cochrane Library, and via hand-searching of conference proceedings. Prospective randomised controlled trials and observational studies including adult patients with MR reporting on treatment response rates, survival, time-to-treatment failure, quality of life, and adverse events were eligible for inclusion.

Results

In total, 32 publications met the inclusion criteria (9 in functional, 18 in organic, and 5 in functional/organic). Despite study heterogeneity, an increased risk of mortality and morbidity was observed which increased with MR severity. Risk factors associated with mortality and morbidity included advancing age, presence of atrial fibrillation, increasing effective regurgitant orifice, ejection fraction, left ventricle end systolic diameter, diabetes, and increasing New York Heart Association class.

Conclusions

The current review represents one of the most comprehensive conducted in the medical/conservative management of MR. An increased risk of mortality and morbidity, which appeared to rise with greater severity, was associated with MR (versus no MR). An unmet need exists in the management of patients with severe symptomatic MR and a high surgical risk as they have a poor prognosis and limited treatment options. Further research into alternative medical strategies and patient management is needed to improve prognoses and reduce mortality and morbidity.