From the Guidelines
Functional mitral regurgitation due to left ventricular dilatation typically does not require a metallic valve replacement. The management of this condition should prioritize optimization of medical therapy for the underlying heart failure, as emphasized in the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1. This includes the use of ACE inhibitors, beta-blockers, and diuretics to improve symptoms and reduce morbidity.
Key Considerations
- Optimization of guideline-directed medical therapy (GDMT) can improve secondary mitral regurgitation (MR) associated with left ventricular (LV) dysfunction and may obviate the need for intervention 1.
- Patients with persistent severe secondary MR despite GDMT may benefit from either surgical or transcatheter repair, depending on the clinical scenario, as suggested by recent trials such as the COAPT trial 1.
- The decision between mitral valve repair, bioprosthetic replacement, or metallic valve replacement should be individualized based on the patient's age, comorbidities, contraindications to anticoagulation, expected lifespan, and preferences regarding the risk of reoperation versus the burden of anticoagulation.
Surgical Intervention
When surgical intervention is necessary, mitral valve repair is generally preferred over replacement when feasible, as it preserves the native valve and avoids the need for lifelong anticoagulation. The European Society of Cardiology guidelines on the management of valvular heart disease suggest that restrictive annuloplasty is the main surgical technique for functional mitral regurgitation, with other techniques being considered for LV remodeling 1.
Valve Replacement
If valve replacement is required, a bioprosthetic valve is often chosen over a metallic valve, especially in older patients, to avoid the risks associated with lifelong anticoagulation. Metallic valves may be considered in younger patients who can tolerate long-term anticoagulation therapy with warfarin. The primary goal of intervention is to address the underlying ventricular dysfunction while restoring proper valve function, thereby improving morbidity, mortality, and quality of life.
From the Research
Functional Mitral Regurgitation Treatment
- Functional mitral regurgitation (FMR) due to left ventricular dilatation is a complex condition that requires a comprehensive treatment approach 2, 3.
- Guideline-directed medical therapy (GDMT) for left ventricular dysfunction and heart failure is the cornerstone of initial treatment, with emphasis on treating the underlying left ventricular dysfunction 2, 3.
- Surgical correction of FMR is controversial, as it typically does not address the underlying mechanism and etiology of the condition 3.
- However, mitral valve surgery may be considered in patients undergoing coronary artery bypass grafting (CABG) with moderate or greater FMR, and in patients with severe symptomatic FMR that persists despite optimal GDMT and revascularization 2, 4.
- Percutaneous options for treatment of FMR, such as the MitraClip system, have shown promise in selected patients 3, 5.
- Transcatheter mitral valve replacement systems are also emerging as a potential treatment option for FMR, although more research is needed to determine their efficacy and safety 5.
Metallic Valve Replacement
- There is no clear evidence to suggest that metallic valve replacement is necessary for functional mitral regurgitation due to left ventricular dilatation 2, 3, 5, 4, 6.
- In fact, the current treatment guidelines recommend a more conservative approach, with a focus on medical therapy and minimally invasive procedures 2, 3.
- However, in some cases, surgical intervention, including mitral valve repair or replacement, may be necessary to alleviate symptoms and improve outcomes 4.
Treatment Outcomes
- The outcomes of patients with functional mitral regurgitation and left ventricular dilatation are generally poor, with high mortality rates 5, 4.
- Treatment with GDMT and minimally invasive procedures has been shown to improve symptoms and reduce hospitalizations, but the impact on long-term outcomes is still uncertain 3, 5.
- Further research is needed to determine the most effective treatment strategies for functional mitral regurgitation due to left ventricular dilatation 2, 3, 5, 4, 6.