Long-term follow-up of open commissurotomy versus bileaflet valve replacement for rheumatic mitral stenosis

Meta-Analysis of Mitral Valve Repair Versus Replacement for Rheumatic Mitral Valve Disease

BACKGROUND

Rheumatic heart disease remains one of the leading causes of heart valve disease worldwide despite being a preventable condition. Mitral valve repair is superior to replacement in severe degenerative mitral valve disease, however its role in rheumatic valve disease remains controversial. This meta-analysis compared mitral valve repair and replacement in rheumatic heart disease.

METHODS

Medline, EMBASE, Cochrane and Scopus were searched from January 1980 to June 2016 for original studies reporting outcomes of both mitral valve repair and replacement in rheumatic heart disease in adults, children or both. Two (2) authors independently assessed studies for inclusion, followed by data extraction and analysis.

RESULTS

The search yielded 930 articles, with 98 full-texts reviewed after initial screening and 13 studies subsequently included for analysis, totalling 2,410 mitral valve repairs and 3,598 replacements. Pooled rates and odds ratio (95% confidence interval) for operative mortality of repair versus replacement was 3.2% versus 4.3%, 0.68 (0.50-0.92; p=0.01). Pooled odds ratios (95% confidence interval) were for long-term mortality 0.41 (0.30-0.56; p<0.001); reoperation 3.02 (1.72-5.31; p<0.001); and bleeding 0.26 (0.11-0.63; p=0.003). There was a trend towards lower thrombo-embolism 0.42 (0.17-1.03; p=0.06), and no significant difference in endocarditis (p=0.76), during follow-up.

CONCLUSION

Mitral valve repair is associated with reduction in operative and long-term mortality and bleeding, so is recommended in rheumatic mitral valve disease where feasible, but it does entail a higher rate of reoperation during follow-up.

Clinical outcomes following surgical mitral valve repair or replacement in patients with rheumatic heart disease: a meta-analysis

Background

The clinical outcome of mitral valve repair (MVP) is considerably more favorable than that of mitral valve replacement (MVR) in patients with degenerative mitral disease. However, rheumatic heart disease (RHD) is still the predominant cause of mitral valve surgery in developing countries and the advantages of MVP in RHD have still not been definitely proven. The aim of this meta-analysis was thus to evaluate the suitability of MVP in patients with RHD. Considering the difference between mechanical and biological valves, we distinguished them from each other and compared them with MVP individually.

Methods

A comparison of clinical outcomes of MVP and MVR in patients with RHD was performed based on clinical trial data. Relevant articles published from January 1, 1990 until March 1, 2020 were identified in Pubmed, Cochrane Library, and China National Knowledge Infrastructure database (CNKI). Studies that lacked direct comparisons between MVP and MVR were excluded.

Results

A total of 16 studies with 8659 patients were included in the analysis. The MVP group displayed lower early and long-term mortality, and fewer valve-related events and major adverse events. However, this patient group required more reoperations compared with the MVR group. Similar results were observed after distinguishing between mechanical and bioprosthetic valves to compare MVP with MVR (mech-valves), but no statistically significant difference was identified in the reoperation rate between MVP and MVR (bio-valves). MVP was further associated with increased risk of mitral reoperation in patients undergoing concomitant aortic valve replacement (AVR) surgery but without any improved early and long-term survival.

Conclusions

MVP and MVR are beneficial for patients with RHD. For skilled surgeons, MVP can be performed for some suitable patients with RHD and is preferred for elderly patients or patients with contraindications of anticoagulation. However, MVR is more appropriate when concomitant AVR is needed.

Open mitral commissurotomy

Closed mitral commissurotomy for rheumatic mitral valve stenosis was used in many tens of thousands of patients with excellent immediate results and durability, many patients having survived more than 20 years without reoperations. Gradually, this procedure was displaced by the open commissurotomy which has the advantage of direct visualisation of all valve components with immediate assessment of the anatomical and functional result. Open commissurotomy is applicable even in moderately fibrosed and/or calcified valves and in the presence of intra-atrial thrombus. Its results are well established and have not yet been bettered by less invasive procedures, such as percutaneous balloon mitral commissurotomy.

Open mitral commissurotomy in the current era: indications, technique, and results

BACKGROUND

The present retrospective study is focused on indications, techniques, and results of open mitral commisurotomy in the current era.

METHODS

Of the 1,280 patients undergoing open-heart surgical procedures for rheumatic mitral stenosis between January 1990 and July 2000, 276 (21.6%) patients underwent open mitral commissurotomy. Major indications included presence of left atrial thrombus/clot (n = 82, 29.7%), severe subvalvular disease (n = 110, 39.8%), mitral valve calcification (n = 42, 15.2%), mild mitral regurgitation (n = 28, 10.0%), associated aortic valve disease (n = 55, 19.9%), organic tricuspid valve disease (n = 20, 7.2%), and failure or restenosis after closed or balloon mitral valvuloplasty (n = 55, 19.9%). Age of patients ranged from 7 to 67 years (mean, 30.2 +/- 12 years). The majority (76%) were in New York Heart Association class III or IV, and 6.9% were in congestive heart failure. Atrial fibrillation was present in 134 (48.6%) patients. Mitral valve area ranged from 0.3 to 0.7 cm2 (mean, 0.52 +/- 0.12 cm2). Mid-diastolic gradients across the mitral valve ranged from 8 to 34 mm Hg (mean, 14.5 +/- 6.2 mm Hg), and end-diastolic gradients ranged from 8 to 42 mm Hg (mean, 15.2 +/- 5.7 mm Hg). Open mitral commissurotomy was performed using standard cardiopulmonary bypass. Associated aortic valve procedure was performed in 55 patients, and either tricuspid valvotomy or repair was performed in 28 patients.

RESULTS

There were four early deaths. All these patients had associated aortic valve procedure (Ross procedure in 2 and homograft aortic valve replacement in 2). Three patients developed severe mitral regurgitation in early postoperative period (< or = 30 days) and required reoperation. Predischarge echocardiography showed mitral valve area from 1.4 to 3.5 cm2 (mean, 2.6 +/- 0.6cm2) and moderate mitral regurgitation in 4 patients. Follow-up ranged from 1 to 130 months (mean, 64.5 +/- 28.6 months). There was no late death. There were three reoperations for mitral valve failure, and an additional 2 patients developed severe mitral stenosis (mitral valve area < 1.0 cm2). In operative survivors, freedom from mitral valve failure at 10 years was 87.0% +/- 3.5%. In patients with isolated open mitral commissurotomy, the incidence of thromboembolism was 0.5%/patient-year.

CONCLUSIONS

Open mitral commissurotomy provides excellent early and long-term results in a selected group of patients.

[Mitral valve repair versus mitral valve replacement]

Over the past 40 years mitral valve surgery has changed dramatically. After initial enthusiasm with the introduction of valve prostheses in the 1960s, a renewed interest in repair techniques began in the 1970s with the introduction of annuloplasty rings. These repair techniques revealed that the integrity of the subvalvular apparatus plays an important role in left ventricular function. When considering the major series comparing early and late results of mitral valve repair versus prosthetic mitral valve replacement, operative mortality rate is lower for patients with mitral valve repair. Long-term results also show a superior survival rate after mitral valve reconstruction. In addition, several problems can occur with the prosthetic valve, such as thromboembolism and endocarditis. All of these factors favor valve repair over replacement. The success of mitral valve repair depends on many factors: etiology of the mitral valve disease and the resultant pathomorphology of the valve, patient's circumstances such as age or contraindication for anticoagulation, and the experience of the surgeon. The decision whether to repair or replace the mitral valve depends on these factors. Data in the literature and in large collective databases reflect the advantages of mitral valve repair, with over 75 % of current mitral valve surgeries being repairs.In the past 5 years the exposure of the mitral valve through a right lateral minithoracotomy using video assistance has developed into a widespread technique. This approach allows complex mitral valve repair as well as mitral valve replacement even with biological stentless prostheses, with decreased morbidity. The addition of radiofrequency ablation for restoration of sinus rhythm enhances the outcome after mitral valve surgery, and can also be easily performed through a minithoracotomy technique.