Impact of secondary mitral valve chordal cutting on valve geometry in obstructive hypertrophic cardiomyopathy with marked septal hypertrophy.

In obstructive HCM, displacement of the MV apparatus into the outflow tract interferes with the ejection flow. Resection of fibrotic secondary chordae moves the MV apparatus away from the outflow tract and enlarges the outflow area independently of septal thickness, facilitating septal myectomy by reducing the need for a deep muscular excision.