The Geoform disease-specific annuloplasty system: a finite element study

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Medical Device Design

Background:

• Functional mitral regurgitation (FMR) involves impaired mitral leaflet coaptation due to functional and geometric issues.
• Standard annuloplasty, while common, may be insufficient for severe FMR.
• FMR-specific rings offer a potential for improved surgical outcomes.

Purpose of the Study:

• To compare the performance of the novel Geoform ring with a standard Physio annuloplasty ring for FMR correction.
• To evaluate the efficacy of these devices in simulated FMR conditions using finite element modeling.

Main Methods:

• Finite element modeling simulated dilated cardiomyopathy-related FMR with varying degrees of papillary muscle displacement.
• The Geoform and Physio annuloplasty rings were modeled in three sizes to assess their impact on valve dynamics.
• Key parameters evaluated included regurgitant area, coaptation length, and leaflet stresses.

Main Results:

• The Geoform ring consistently achieved coaptation lengths over 7 mm, with a 74% reduction in regurgitant area in severe cases.
• Leaflet stresses were reduced by 20% with the Geoform ring, even with simulated undersizing.
• The standard Physio ring resulted in a maximum coaptation length of 4.3 mm and a 60% regurgitant area reduction.

Conclusions:

• Disease-specific prostheses like the Geoform ring can effectively restore mitral valve competence in cases of significant leaflet tethering.
• These specialized devices may eliminate the need for aggressive undersizing, potentially leading to more durable surgical results.
• The Geoform ring demonstrates promising performance for addressing severe functional mitral regurgitation.