Mitral repair best practice: proposed standards

Long-term mitral valve repair outcomes and hospital volume: 15 years' analysis of an administrative dataset

BACKGROUND

Procedural volume has been documented as an important contributor to operative outcomes for most complex surgical procedures. Mitral valve repair (MVRep) has been associated with excellent results, and it is increasingly adopted in many cardiac surgical centers. We sought to investigate if procedural volume is associated with better clinical long-term outcomes after MVRep.

METHODS

We analyzed the 10-year outcomes after MVRep by procedural volume for each cardiac surgery center in an Italian Region, Lazio, during the last 15 years, using a regional administrative dataset.

RESULTS

Between 2006 and 2020, 4961 patients were treated in seven cardiac surgery centers for an isolated mitral valve surgery (2677 underwent MVRep). At multivariate analysis, mitral valve replacement (MVR) (vs. MVRep) resulted one of the independent predictors of 30-day mortality [adjusted odds ratio (OR) 3.40; 95% confidence interval (CI) 1.96-5.90; P  < 0.0001]. Notably, a clear association between hospital volume of mitral valve surgery (>40 per year) and high rate of MVRep (>50%) was found. At 10 years, the incidence of mortality and the rate of death and rehospitalization for heart failure after MVRep were significantly lower in high-volume vs. low-volume hospitals.

CONCLUSION

Our data suggest that hospital volume is associated with a high rate of MVRep and long-term benefits in terms of mortality and recurrence of heart failure.

Trends in Isolated Mitral Valve Repair or Replacement Surgery in Australia: A Statewide Cohort Linkage Study

BACKGROUND

Global trends in mitral valve surgery (MVSx) suggest increasing repair compared with replacement, especially in the United States and European countries. The relative use, and outcomes of, MV repair and replacement in Australia are unknown.

METHODS

New South Wales residents who underwent isolated MVSx between 2001 and 2017 were identified from the Admitted-Patient-Data-Collection database. Mortality outcomes were tracked to 31 Dec 2018 and adjusted based on age, sex, urgency of operation, and comorbidity status.

RESULTS

The study cohort comprised 5,693 patients: 2020 (35%) underwent repair (MVr), 1,656 (29%) underwent mechanical replacement (mech.MVR), and 2017 (35%) underwent bioprosthetic replacement (bio.MVR). Respective median ages [interquartile range] were 67 yo [59-75 yo], 64 yo [55-71 yo], and 75 yo [68-80 yo] (p<0.001 across groups). Between 2001 and 2017, total MVSx increased steadily with population growth. Whereas the relative use of MVr remained static (34% to 38%), that for bio.MVR (22% to 50%) and mech.MVR (45% to 13%) changed significantly. MVr had the best outcome with 1.2% in-hospital, 2.5% 1-year, and 21.6% total cumulative mortality during a median follow-up of 6.5 years. Compared to MVr, the adjusted hazard ratio (aHR) for mech.MVR and bio.MVR for long-term mortality were 1.41 (95% confidence interval [CI]=1.24-1.61) and 1.73 (95% CI=1.53-1.95), respectively. Heart failure and sepsis were the main cardiovascular and noncardiovascular causes of death in all groups.

CONCLUSION

In this statewide Australian cohort examined over 17 years, MVr is potentially underutilised despite having superior outcomes to MVR. Access to quality dataset which provides the indication for MVSx and quantitative clinical factors is critical to further improve MVr coverage and outcome MVSx.

Concomitant Valve Replacement and Coronary Artery Bypass Grafting Surgery: Lessons from the Past, Guidance for the Future? A Mortality Analysis in 294 Patients

OBJECTIVE

The aims of this study were to analyze parameters influencing early and late mortality after concomitant valve replacement and coronary artery bypass grafting surgery, using early and long-term information from an institutionally available data registry, and to discuss the results in relation to the current treatment strategies and perspectives.

METHODS

The study population consisted of 294 patients after combined valve replacement with mechanical prosthesis and CABG surgery.

RESULTS

There were 201 men (68.4%) and 93 women (31.6%). Concurrent to the coronary artery bypass grafting, 238 patients (80.9%) underwent aortic-, 46 patients (15.6%) mitral- and 10 patients (3.4%) doublevalve replacement. Cumulative duration of follow up was 1007 patient-years (py) with a maximum of 94 months and was completed in 92.2% (271 cases). Overall hospital mortality (30 days) rate was 6.5% (n = 19). It was significantly higher in patients of female gender, older than 70 y, in those suffering preoperative myocardial infarction, presenting with an additive EuroScore > 8 and being hemodynamically unstable after the operation. Cumulative survival rate at 7.6 y was 78.6%. Determinants of prolonged survival were male gender, age at operation < 70 y, preoperative sinus rhythm, normal renal function, additive EuroScore < 8 and the use of internal thoracic artery for grafting. Subsequent multivariate analysis revealed preoperative atrial fibrillation (HR: 2.1, 95% CI: 0.82-5.44, p: 0.01) and risk group of ES > 8 (HR: 3.63, 95% CI: 1.45-9.07, p < 0.01) as independent predictors for lower long-term survival.

CONCLUSIONS

Hospital mortality (30 d) was nearly 2.5-fold higher in female and/or older than 70 y patients. Preoperative atrial fibrillation and/ or a calculated ES > 8 were independent predisposing factors of late mortality for combined VR and CABG surgery. Tailoring the approach, with the employment of the newest techniques and hybrid procedures, to the individual patient clinical profile enables favorable outcomes for concomitant valvular disease and CAD, especially in high-risk patients.

Association between individual surgeon volume and outcome in mitral valve surgery: a systematic review

Background

Surgeon volume has been identified as a possible factor that influences outcomes in mitral valve (MV) surgery. The aim of this study was to systematically review all published studies on the association between individual surgeon volume and outcome in MV surgery.

Methods

PubMed was searched last on 19 November 2020. The reporting of this systematic review was done in accordance with PRISMA guidelines. Manuscripts were eligible when these studied individual surgeon volumes and its association with repair rate, mortality or reoperation. The methodological quality of the studies was assessed with the Newcastle-Ottawa Scale (NOS). Absolute numbers and percentages of the outcome measures, odds ratios (ORs), P values and threshold values regarding surgeon volume were collected.

Results

A total of 7 retrospective cohort studies were included in the qualitative analysis with total of 158488 patients. Definitions of surgeon volumes were found to be heterogenic and therefore pooling of data was not possible. Surgeon volume was significantly associated with repair rate (OR =1.25–5.5) and mortality (OR =0.46–0.84 and OR =1.50–2.27 depending on the reference group). Regarding reoperation, results were not consistent and did not always show a significant lower reoperation rate when surgeon volume increased. A mean threshold of minimally 30 MV surgeries per year was found.

Discussion

Higher surgeon volume is significantly associated with improved outcomes of repair rate and mortality. MV should preferentially be performed by high-volume surgeons and centralization of MV surgery might be necessary.

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.

Mitral valve repair rates in degenerative mitral valve disease correlate with surgeon and hospital procedural volume

STUDY AIM

To determine the relationship between surgeon and hospital procedural volume, and mitral valve repair rates and 30-day mortality for degenerative mitral regurgitation (MR), in Australian cardiac surgical centers.

METHODS

A total of 4420 patients who underwent elective surgery for degenerative MR between January 2008 and December 2017 in the Australian and New Zealand Society of Cardiac and Thoracic Surgeons Database were retrospectively included. Univariate and multivariate regression analyses examined surgeon and hospital procedural volumes for associations with repair rate and mortality.

RESULTS

Repair rates varied widely by caseload; from 62.57% to 79.53% for lowest to highest volume surgeons; and from 54.56% to 77.54% for lowest to highest volume hospitals. Compared to surgeons performing ≤5 procedures/annum, surgeons performing 10.1-20/annum were more likely to repair the valve (odds ratio [OR] 2.40, 95% confidence interval [CI] 1.09-5.28, p = .03), particularly if performing more than 20/annum (OR 2.88, 95% CI 1.09-7.60, p = .03). Compared to hospitals performing ≤10/annum, those performing any number of procedures more than 10 demonstrated an increased likelihood of repair (caseload 10.1-20/year OR 1.96, 95% CI 1.25-3.07, p = .003) though odds did not increase above this threshold. Low incidence of 30-day mortality (63 of 4414, 1.43%) limited analysis of contributing variables; procedural volume did not confer a survival benefit.

CONCLUSIONS

Surgeon and hospital caseload were significantly associated with repair rates of degenerative MR. A threshold minimum of 10 procedures annually for surgeons and hospitals should be utilized to maximize repair rates, and ideally of 20 for surgeons. Mortality was low and may not be significantly impacted by procedural volume.

Volume-Outcome Association of Mitral Valve Surgery in the United States

Importance

Early surgery for severe primary degenerative mitral regurgitation is recommended, provided optimal outcomes are achievable. Contemporary national data defining mitral valve surgery volume and outcomes are lacking.

Objective

To assess national 30-day and 1-year outcomes of mitral valve surgery and define the hospital- and surgeon-level volume-outcome association with mitral valve repair or replacement (MVRR) in patients with primary mitral regurgitation.

Design, Setting, and Participants

This multicenter cross-sectional observational study used the Society of Thoracic Surgeons Adult Cardiac Surgery Database to identify patients undergoing isolated MVRR for primary mitral regurgitation in the United States. Operative data were collected from July 1, 2011, to December 31, 2016, and analyzed from March 1 to July 1, 2019, with data linked to the Centers for Medicare and Medicaid Services.

Main Outcomes and Measures

The primary outcome was 30-day in-hospital operative mortality after isolated MVRR for primary mitral regurgitation. Secondary outcomes were 30-day composite mortality plus morbidity (any occurrence of bleeding, stroke, prolonged ventilation, renal failure, or deep wound infection), rate of successful mitral valve repair of primary mitral regurgitation (residual mitral regurgitation of mild [1+] or better), and 1-year mortality, reoperation, and rehospitalization for heart failure.

Results

A total of 55 311 patients, 1094 hospitals, and 2410 surgeons were identified. Increasing hospital and surgeon volumes were associated with lower risk-adjusted 30-day mortality, lower 30-day composite mortality plus morbidity, and higher rate of successful repair. The lowest vs highest hospital volume quartile had higher 1-year risk-adjusted mortality (hazard ratio [HR], 1.61, 95% CI, 1.31-1.98), but not mitral reoperation (odds ratio [OR], 1.51; 95% CI, 0.81-2.78) or hospitalization for heart failure (HR, 1.25; 95% CI, 0.96-1.64). The surgeon-level 1-year volume-outcome associations were similar for mortality (HR, 1.60; 95% CI, 1.32-1.94) but not significant for mitral reoperation (HR, 1.14; 95% CI, 0.60-2.18) or hospitalization for heart failure (HR, 1.17; 95% CI, 0.91-1.50).

Conclusions and Relevance

National hospital- and surgeon-level inverse volume-outcome associations were observed for 30-day and 1-year mortality after mitral valve surgery for primary mitral regurgitation. These findings may help to define access to experienced centers and surgeons for the management of primary mitral regurgitation.

Impact of Mitral Valve Repair Case Volume on Postoperative Mortality - A Nationwide Korean Cohort Study

BACKGROUND

Although mitral valve repair is recommended over replacement due to better outcomes, repair rates vary significantly among centers. This study examined the effect of institutional mitral valve repair volume on postoperative mortality.Methods and Results:All cases of adult mitral valve repair performed in Korea between 2009 and 2016 were analyzed. The association between case volume and 1-year mortality was analyzed after categorizing centers according to the number of mitral valve repairs performed as low-, medium-, or high-volume centers (<20, 20-40, and >40 cases/year, respectively). The effect of case volume on cumulative all-cause mortality was also assessed. In all, 6,041 mitral valve repairs were performed in 86 centers. The 1-year mortality in low-, medium-, and high-volume centers was 10.1%, 8.7%, and 4.7%, respectively. Low- and medium-volume centers had increased risk of 1-year mortality compared with high-volume centers, with odds ratios of 2.80 (95% confidence interval [CI] 2.15-3.64; P<0.001) and 2.66 (95% CI 1.94-3.64; P<0.001), respectively. The risk of cumulative all-cause mortality was also worse in low- and medium-volume centers, with hazard ratios of 1.96 (95% CI 1.68-2.29; P<0.001) and 1.77 (95% CI 1.47-2.12; P<0.001), respectively.

CONCLUSIONS

Lower institutional case volume was associated with higher mortality after mitral valve repair. A minimum volume standard may be required for hospitals performing mitral valve repair to guarantee adequate outcome.

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.

Patient and Hospital Characteristics of Mitral Valve Surgery in the United States

Importance

Volume metrics may have relevance in the evaluation of valve center expertise. However, a paucity of data exists regarding the quantity, volume, and geographic location of mitral valve (MV) surgical centers in the United States and the proportion of underserved populations they treat.

Objectives

To evaluate the hospital, patient, and procedural characteristics of mitral valve repair or replacement (MVRR) in the United States as a function of hospital procedure volume.

Design, Setting, and Participants

This cross-sectional, multicenter observational study was conducted from July 2014 to June 2018. Patients in the Society of Thoracic Surgeons Adult Cardiac Surgery Database undergoing any surgical procedure involving MVRR in the United States were included.

Main Outcomes and Measures

Volume distribution of MVRR by hospital and hospital referral region.

Results

There were 165 405 MVRRs performed in 1082 centers during the study period, of which 86 488 (52.3%) were MV repairs. There were 575 centers (53.1%) that performed 25 or more MVRRs per year. The geographic distribution of centers performing 25 or more MVRRs per year differed from those performing fewer than 25 MVRRs per year. Of 304 designated hospital referral regions, 235 (77.3%) had at least 1 center performing 25 or more MVRRs per year, representing accessibility to 1 or more such centers for 296.4 million of 320.1 million US residents (92.6% of the US population; Midwest, 60.0 million of 68.0 million [88.4%]; South, 112.6 million of 122.6 million [91.9%]; West, 68.6 million of 72.9 million [94.1%]; and Northeast, 54.9 million of 56.6 million [97.1%]). Of 304 hospital referral regions, 168 (55.3%) had at least 1 center performing 40 or more MVRRs per year, representing accessibility to 1 or more such centers for 259.8 million of 317.90 million (81.7%) of the US population (Midwest, 50.5 million of 67.9 million [74.5%]; South, 94.5 million of 121.1 million [78.1%]; West, 64.0 million of 72.8 million [88.0%]; Northeast, 50.1 million of 56.3 million [90.2%]). More black and Hispanic patients received operations in centers performing 25 or more MVRRs per year (22 984) vs those performing fewer than 25 MVRRs per year (3227), yet the proportion was higher in lower-volume centers (22 984 of 148 385 [15.5%] vs 3227 of 17 020 [19.0%]; P < .001). In centers performing 25 or more MVRRs per year vs fewer than 25 MVRRs per year, there was a lower percentage of Medicare and Medicaid patients (47 920 of 148 385 [32.3%] vs 6183 of 17 020 [.3%]; P < .001) and patients from rural zip codes (21 208 of 148 385 [14.3%] vs 3146 of 17 020 [18.5%]; P < .001).

Conclusions and Relevance

Fifty-three percent of all centers performed 25 or more MVRRs per year, and 92.6% of the US population lived in an hospital referral region with at least 1 such center. Disparities in race/ethnicity, rurality, and insurance status exist among patients being treated at centers with different volumes. These data indicate that efforts to centralize care based on volume metrics will need to balance access vs quality.

New Insights into Valve Hemodynamics

Heart valve diseases are common disorders with five million annual diagnoses being made in the United States alone. All heart valve disorders alter cardiac hemodynamic performance; therefore, treatments aim to restore normal flow. This paper reviews the state-of-the-art clinical and engineering advancements in heart valve treatments with a focus on hemodynamics. We review engineering studies and clinical literature on the experience with devices for aortic valve treatment, as well as the latest advancements in mitral valve treatments and the pulmonic and tricuspid valves on the right side of the heart. Upcoming innovations will potentially revolutionize treatment of heart valve disorders. These advancements, and more gradual enhancements in the procedural techniques and imaging modalities, could improve the quality of life of patients suffering from valvular disease who currently cannot be treated.

Combined Degenerative Mitral Valve and Coronary Surgery: Early Outcomes and 10-Year Survival

BACKGROUND

This study investigated the impact of combined degenerative mitral valve (DMV) and coronary artery bypass grafting (CABG+DMV) surgery vs DMV surgery only on in-hospital health outcome and 10-year survival.

METHODS

We identified 745 patients with DMV disease. Of these, 186 (24.9%) were affected also by coronary disease and underwent combined DMV+CABG. They were compared with the remaining 559 patients receiving DMV-only surgery in in-hospital and 1-, 5-, and 10-year survival. We evaluated a short-term composite outcome of hospital mortality, acute kidney injury, cerebrovascular events, and low cardiac output requiring postoperative use of intraaortic balloon pump. In addition, we assessed mitral valve repair rates over time and their correlation with long-term survival. To minimize bias, we conducted a propensity score-matching analysis.

RESULTS

DMV+CABG surgery was associated with a similar incidence of the composite end point compared with DMV-only surgery in the unmatched analysis (6.5% vs 5.4%, P = .71) and matched analysis (7.5% vs 8.2%, P = .82). The 10-year survival was 70.5% vs 68.6% (P = .07) for the unmatched analysis and 64.6% vs 62.5% (P = .9) for the matched analysis, DMV+CABG vs DMV-only, respectively. Mitral valve repair had a beneficial effect on short-term outcomes and long-term mortality rates, regardless the presence of concomitant coronary surgery.

CONCLUSIONS

Combined DMV+CABG surgery is a very effective surgical treatment with high mitral valve repair rate. Early in-hospital outcome and long-term survival are comparable with DMV-only surgery. In these combined procedures, mitral valve repair is associated with better long-term survival.

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.

Outcomes after mitral valve surgery for rheumatic heart disease

Objective

To further the understanding of the factors influencing outcome following rheumatic heart disease (RHD) related mitral valve surgery, which globally remains an important cause of heart disease and a particular problem in Indigenous Australians.

Methods

The Australian Cardiac Surgery Database was utilised to assess outcomes following mitral valve repair and replacement for RHD and non-RHD valve disease. The association with aetiology, demographics, comorbidities, preoperative status and operative procedure was evaluated.

Results

Mitral valve repairs and replacements undertaken in Australia were analysed from 119 and 1078 RHD surgical procedures and 3279 and 2400 non-RHD procedures, respectively. RHD mitral valve repair, compared with replacement, resulted in a slightly shorter hospital stay and more reoperation for valve dysfunction, but no difference in 30-day survival. In unadjusted survival analysis to 5 years, RHD mitral valve repair and replacement were no different (HR 0.86, 95% CI 0.4 to 1.7), non-RHD repair was superior to replacement (HR 1.7, 95% CI 1.4 to 2.0), RHD and non-RHD repair were no different (HR 0.9, 95% CI 0.5 to 1.7), and RHD replacement was superior to non-RHD (HR 1.5, 95% CI 1.2 to 1.9). None of these differences persisted in adjusted analyses and there was no difference in long-term survival for Indigenous Australians.

Conclusion

In this large prospective cohort study we have demonstrated that adjusted long-term survival following RHD mitral valve repair surgery in Australia is no different to replacement and no different to non-RHD. Interpretation of valve surgery outcome requires careful consideration of patient factors that may also influence survival.

Mitral valve repair for degenerative mitral valve disease: surgical approach, patient selection and long-term outcomes

Mitral valve repair (MVRepair) has become the procedure of choice to correct severe degenerative mitral regurgitation (MR), due to its documented superiority to valve replacement regarding long-term survival, freedom from valve-related adverse events and preservation of left ventricular (LV) function. The refinement of MVRepair techniques has rendered almost all valves (more than 95%) amenable to repair with a 15-year freedom from reoperation of 90%. The concept of 'centres of excellence for MVRepair' has emerged, encouraging referring doctors to select the most experienced institutions or individual surgeons to deal with the most complex cases, based on repair volume, appropriate peri-procedural imaging and data regarding expected outcomes (repair, mortality and durability of repair). Based on the good results, operating on asymptomatic patients with severe MR is now widely accepted, prophylactically avoiding the dire consequences of chronic MR, such as LV function deterioration/enlargement, and development of atrial fibrillation and pulmonary hypertension. In reference centres, where the repair rate is over 95% for all types of disease with <1% mortality, it has become standard practice in nearly 50%-60% of all patients submitted to MVRepair. Finally, recent advances in the surgical treatment with the purpose of reducing invasiveness and surgical trauma, through partial sternotomy or mini-thoracotomy (video-assisted with or without robotics), are now being increasingly performed in 20%-30% of centres, claiming comparable results to conventional surgery. In addition, transcatheter technology, particularly the MitraClip, is evolving and treading its way in the treatment of high-risk patients with severe MR, but the results are still short of ideal.

Relation of Mitral Valve Surgery Volume to Repair Rate, Durability, and Survival

BACKGROUND

Degenerative mitral valve repair rates remain highly variable, despite established benefits of repair over replacement. The contribution of surgeon-specific factors is poorly defined.

OBJECTIVES

This study evaluated the influence of surgeon case volume on degenerative mitral valve repair rates and outcomes.

METHODS

A mandatory New York State database was queried and 5,475 patients were identified with degenerative mitral disease who underwent mitral valve operations between 2002 and 2013. Mitral repair rates, mitral reoperations within 12 months of repair, and survival were analyzed using multivariable Cox modeling and restricted cubic spline function.

RESULTS

Median annual surgeon volume of any mitral operations was 10 (range 1 to 230), with a mean repair rate of 55% (n = 20,797 of 38,128). In the subgroup of patients with degenerative disease, the mean repair rate was 67% (n = 3,660 of 5,475), with a range of 0% to 100%. Mean repair rates ranged from 48% (n = 179 of 370) for surgeons with total annual volumes of ≤10 mitral operations to 77% (n = 1,710 of 2,216) for surgeons with total annual volumes of >50 mitral operations (p < 0.001). Higher total annual surgeon volume was associated with increased repair rates of degenerative mitral valve disease (adjusted odds ratio [OR]: 1.13 for every additional 10 mitral operations; 95% confidence interval [CI]: 1.10 to 1.17; p < 0.001); a steady decrease in reoperation risk until 25 total mitral operations annually; and improved 1-year survival (adjusted hazard ratio: 0.95 for every additional 10 operations; 95% CI: 0.92 to 0.98; p = 0.001). For surgeons with a total annual volume of ≤25 mitral operations, repair rates were higher (63.8%; n = 180 of 282) if they operated in the same institution as a surgeon with total annual mitral volumes of >50 and degenerative mitral valve repair rates of >70%, compared with surgeons operating in the other institutions (51.3%; n = 580 of 1,130) (adjusted OR: 1.79; 95% CI: 1.24 to 2.60; p < 0.001).

CONCLUSIONS

This study suggests that individual surgeon volume is a determinant of not only mitral repair rates, but also freedom from reoperation, and survival. The data from this study support the guideline's concept of reference referral to experienced mitral surgeons to improve outcomes in patients with degenerative mitral valve disease.

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.

Case load and valve surgery outcome in Australia

BACKGROUND

In Australia it has been suggested that heart valve surgery, particularly for rheumatic heart disease (RHD), should be consolidated in higher volume centres. International studies of cardiac surgery suggest large volume centres have superior outcomes. However the effect of site and surgeon case load on longer term outcomes for valve surgery has not been investigated.

METHODS

The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed. The adjusted association between both average annual site and surgeon case load on short term complications and short and long-term survival was determined.

RESULTS

Outcomes associated with 20,116 valve procedures at 25 surgical sites and by 93 surgeons were analysed. Overall adjusted analysis showed increasing site and surgeon case load was associated with longer ventilation, less reoperation and more anticoagulant complications. Increasing surgeon case load was also associated with less acute kidney injury. Adjusted 30-day mortality was not associated with site or surgeon case load. There was no consistent relationship between increasing site case load and long term survival. The association between surgeon case load and outcome demonstrated poorer adjusted survival in the highest volume surgeon group.

CONCLUSIONS

In this Australian study, the adjusted association between surgeon and site case load was not simple or consistent. Overall larger volume sites or surgeons did not have superior outcomes. Mandating a particular site case load level for valve surgery or a minimum number of procedures for individual surgeons, in an Australian context, cannot be supported by these findings.

Mitral valve disease--current management and future challenges

The field of mitral valve disease diagnosis and management is rapidly changing. New understanding of disease pathology and progression, with improvements in and increased use of sophisticated imaging modalities, have led to early diagnosis and complex treatment. In primary mitral regurgitation, surgical repair is the standard of care. Treatment of asymptomatic patients with severe mitral regurgitation in valve reference centres, in which successful repair is more than 95% and surgical mortality is less than 1%, should be the expectation for the next 5 years. Transcatheter mitral valve repair with a MitraClip device is also producing good outcomes in patients with primary mitral regurgitation who are at high surgical risk. Findings from clinical trials of MitraClip versus surgery in patients of intermediate surgical risk are expected to be initiated in the next few years. In patients with secondary mitral regurgitation, mainly a disease of the left ventricle, the vision for the next 5 years is not nearly as clear. Outcomes from ongoing clinical trials will greatly inform this field. Use of transcatheter techniques, both repair and replacement, is expected to substantially expand. Mitral annular calcification is an increasing problem in elderly people, causing both mitral stenosis and regurgitation which are difficult to treat. There is anecdotal experience with use of transcatheter valves by either a catheter-based approach or as a hybrid technique with open surgery, which is being studied in early feasibility trials.

Standards for heart valve surgery in a 'Heart Valve Centre of Excellence'

Surgical centres of excellence should include multidisciplinary teams with specialist expertise in imaging, clinical assessment and surgery for patients with heart valve disease. There should be structured training programmes for the staff involved in the periprocedural care of the patient and these should be overseen by national or international professional societies. Good results are usually associated with high individual and centre volumes, but this relationship is complex. Results of surgery should be published by centre and should include rates of residual regurgitation for mitral repairs and reoperation rates matched to the preoperative pathology and risk.

Almanac 2012: adult cardiac surgery: the national society journals present selected research that has driven recent advances in clinical cardiology

This review covers the important publications in adult cardiac surgery in the last few years, including the current evidence base for surgical revascularisation and the use of off-pump surgery, bilateral internal mammary arteries and endoscopic vein harvesting. The changes in conventional aortic valve surgery are described alongside the outcomes of clinical trials and registries for transcatheter aortic valve implantation, and the introduction of less invasive and novel approaches of conventional aortic valve replacement surgery. Surgery for mitral valve disease is also considered, with particular reference to surgery for asymptomatic degenerative mitral regurgitation.