What are the differences in minimal invasive mitral valve (MIVR) repair approaches for rheumatic mitral valve disease versus degenerative mitral valve disease?

From the Guidelines

Minimally invasive mitral valve repair (MIMVR) approaches differ significantly between rheumatic and degenerative mitral valve disease due to their distinct pathophysiology. For rheumatic mitral valve disease, MIMVR typically involves commissurotomy, decalcification of leaflets, and often requires extensive subvalvular apparatus modification including papillary muscle splitting and chordal fenestration to address fusion and scarring. These repairs frequently necessitate annuloplasty rings that are complete and rigid to provide adequate support for the scarred valve tissue. In contrast, MIMVR for degenerative disease focuses on addressing excess tissue and prolapse through techniques like leaflet resection, chordal transfer, or artificial chordae implantation, with less extensive subvalvular work. Degenerative repairs often utilize partial, flexible annuloplasty bands that preserve physiologic annular dynamics. Rheumatic repairs generally have lower long-term durability (50-60% at 10 years) compared to degenerative repairs (>90% at 10 years), and patients with rheumatic disease may eventually require valve replacement. The technical complexity of rheumatic repairs often demands greater surgeon experience, while the surgical approach (right minithoracotomy or robotic) remains similar for both pathologies, though more challenging in rheumatic cases due to tissue characteristics and required techniques.

Key differences between rheumatic and degenerative MIMVR include:

• The need for extensive subvalvular modification in rheumatic disease
• The use of complete and rigid annuloplasty rings in rheumatic repairs
• The focus on addressing excess tissue and prolapse in degenerative repairs
• The utilization of partial, flexible annuloplasty bands in degenerative repairs
• The difference in long-term durability between rheumatic and degenerative repairs

According to the 2020 ACC/AHA guideline for the management of patients with valvular heart disease 1, mitral valve repair is recommended in preference to mitral valve replacement when the anatomic cause of MR is degenerative disease, if a successful and durable repair is possible. Additionally, the guideline states that mitral valve repair may be considered in patients with rheumatic mitral valve disease when surgical treatment is indicated if a durable and successful repair is likely or when the reliability of long-term anticoagulation management is questionable 1.

The most recent and highest quality study, the 2020 ACC/AHA guideline 1, prioritizes mitral valve repair over replacement for degenerative disease, and considers repair for rheumatic disease when a durable and successful repair is likely. This guideline provides the most up-to-date recommendations for the management of patients with valvular heart disease, and should be followed in clinical practice to optimize patient outcomes.

In terms of morbidity, mortality, and quality of life, the goal of MIMVR is to improve symptoms, reduce morbidity, and improve long-term survival. The choice of surgical approach and technique should be individualized based on the patient's specific disease characteristics and needs. By prioritizing mitral valve repair over replacement, and considering the unique challenges and requirements of rheumatic and degenerative disease, clinicians can provide optimal care for patients with mitral valve disease.

From the Research

Minimal Invasive Mitral Valve Repair Approaches

• The differences in minimal invasive mitral valve (MIVR) repair approaches for rheumatic mitral valve disease versus degenerative mitral valve disease have been studied in various research papers 2, 3, 4, 5, 6.
• A study published in 2018 found that mitral valve re-repair is feasible and has good mid-term results in patients with degenerative mitral valve disease, while rheumatic mitral valve disease is associated with a certain risk of failure over time 2.
• Another study published in 2010 compared the long-term outcomes of mitral valve repair and replacement in patients with rheumatic mitral valve disease, and found that repair had excellent durability comparable to mechanical valve replacement in selected patients 3.
• A meta-analysis published in 2021 evaluated the suitability of mitral valve repair in patients with rheumatic heart disease, and found that mitral valve repair was associated with lower early and long-term mortality, and fewer valve-related events and major adverse events, but required more reoperations compared to mitral valve replacement 4.
• A study published in 2021 compared the outcomes of minimally invasive and sternotomy mitral valve repair for degenerative mitral valve disease, and found that both approaches had equivalent survival and repair durability 5.
• A study published in 2015 compared the long-term results of mitral valve repair in adults with chronic rheumatic disease and degenerative disease, and found that the durability of rheumatic mitral valve repair had improved and was comparable to the outstanding durability of repairs for degenerative disease 6.

Key Findings

• Mitral valve repair is a suitable treatment option for both rheumatic and degenerative mitral valve disease 2, 3, 4, 5, 6.
• The choice of surgical approach (minimally invasive or sternotomy) does not affect the outcomes of mitral valve repair for degenerative mitral valve disease 5.
• Rheumatic mitral valve disease is associated with a higher risk of failure and reoperation compared to degenerative mitral valve disease 2, 4.
• The durability of mitral valve repair for rheumatic mitral valve disease has improved in recent years, and is now comparable to the durability of repairs for degenerative mitral valve disease 6.