Physiologic Mitral Annuloplasty Ring Sizing: Surgical Technique and Animal Model Validation

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Medical Device Technology

Background:

• Current mitral annuloplasty ring sizing methods are outdated, offering limited surgical guidance.
• Accurate sizing is crucial for successful mitral valve repair and optimizing coaptation length.

Purpose of the Study:

• To validate a novel mitral annuloplasty ring sizing device and technique in a cadaver swine heart model.
• To assess the accuracy of the novel device in predicting coaptation length changes during mitral annuloplasty.

Main Methods:

• Twenty cadaver swine hearts were used to test the paired-ring sizer.
• Anterior leaflet coaptation length was measured at baseline, with the sizer, and after implanting a corresponding commercial ring.
• Bland-Altman analysis compared predicted (sizer) and actual (implanted ring) coaptation lengths.

Main Results:

• The novel sizer accurately predicted final coaptation lengths, with a mean difference of 0.08 mm (95% CI [-0.06, 0.21]).
• The limits of agreement were -0.50 to 0.65 mm, indicating good concordance between predicted and actual lengths.
• A moderate increase in coaptation length was achieved in 19 of 20 hearts.

Conclusions:

• The novel mitral annuloplasty ring-sizing device demonstrated accuracy in a cadaveric swine model.
• The device accurately predicted coaptation lengths, correlating well with commercially available rings.
• This technology promises enhanced surgical control over final coaptation length in mitral valve repair.