What are the surgical indications for valvular heart diseases such as mitral regurgitation, mitral stenosis, aortic stenosis, and aortic regurgitation?

From the Guidelines

Surgical intervention for valvular heart diseases is primarily indicated when patients develop symptoms or show evidence of cardiac dysfunction, even if asymptomatic, with the goal of improving morbidity, mortality, and quality of life. The indications for surgery in valvular heart diseases such as mitral regurgitation, mitral stenosis, aortic stenosis, and aortic regurgitation are as follows:

• For mitral regurgitation, surgery is recommended for symptomatic patients with severe regurgitation, asymptomatic patients with left ventricular ejection fraction (LVEF) <60%, left ventricular end-systolic diameter ≥40mm, or new-onset atrial fibrillation 1.
• Mitral stenosis typically requires intervention when the valve area is <1.5cm² with symptoms, or <1.0cm² even without symptoms, with percutaneous mitral commissurotomy (PMC) being considered as an initial treatment for selected patients with mild to moderate calcification or impaired subvalvular apparatus 1.
• For aortic stenosis, surgery is indicated when severe stenosis (valve area <1.0cm²) is accompanied by symptoms like angina, syncope, or heart failure, or when asymptomatic patients have LVEF <50% or abnormal exercise tests 1.
• Aortic regurgitation warrants surgery when severe and symptomatic, or when asymptomatic with LVEF <50% or left ventricular end-diastolic diameter >70mm or end-systolic diameter >50mm. Some key points to consider in the management of valvular heart diseases include:
• The type of treatment, as well as its timing, should be decided on the basis of clinical characteristics, valve anatomy, and local expertise 1.
• Valve repair is the preferred method for mitral regurgitation when feasible, but mitral valve replacement should be considered in patients with unfavourable morphological characteristics 1.
• Transcatheter approaches are increasingly used, particularly for high-risk surgical candidates.
• Early referral to a cardiac surgeon is essential when patients approach these thresholds to ensure optimal timing of intervention before irreversible cardiac damage occurs. The management of asymptomatic patients is controversial, and surgery can be proposed in selected asymptomatic patients with severe mitral regurgitation, in particular when repair is likely 1.

From the Research

Surgical Indications for Valvular Heart Diseases

The surgical indications for valvular heart diseases such as mitral regurgitation, mitral stenosis, aortic stenosis, and aortic regurgitation are as follows:

• Mitral Regurgitation: Surgery is advisable before patients reach Functional Class III or IV, and before they develop atrial fibrillation, an ejection fraction of under 0.55, or marked left ventricular and atrial enlargement 2. Mitral valve repair is the best treatment in many patients, particularly those with degenerative valve lesions, poor ejection fraction, elderly people, and some cases of infective endocarditis 2.
• Mitral Stenosis: There is no direct evidence provided for the surgical indications of mitral stenosis.
• Aortic Stenosis: There is no direct evidence provided for the surgical indications of aortic stenosis.
• Aortic Regurgitation: There is no direct evidence provided for the surgical indications of aortic regurgitation.

Specific Considerations for Mitral Regurgitation

• In patients with functional mitral regurgitation (FMR), mitral valve repair is the treatment of choice, especially in patients younger than 65 years, with an ischemic origin of MR, a poor ejection fraction, a severe LV dilatation, and atrial fibrillation 3.
• In patients with reduced left ventricular ejection fraction (LVEF), mitral valve repair provides superior long-term results compared with replacement, and severe LV dysfunction is a significant predictor of reduced survival following MV surgery 4.
• For severe ischemic mitral regurgitation, there is no significant difference in left ventricular reverse remodeling or survival at 12 months between patients who underwent mitral-valve repair and those who underwent mitral-valve replacement, but replacement provided a more durable correction of mitral regurgitation 5.

General Considerations

• The surgical approach depends on two factors: the possibility of valve repair evaluated by transthoracic and transoesophageal echocardiography, and the experience of the surgical team in this kind of surgery 2.
• Increased repair rate, better definition of the role of surgery in both ischemic and myopathic MR, and the role of limited incision surgery are all important considerations for the future of mitral valve surgery 6.