Impact of Anchor Location on Mitral Neochordae Forces: An In Vitro Study

Abstract

Purpose: This study examined changes in force distribution between the neochordae corresponding to different ventricular anchor locations.

Description: Seven porcine mitral valves were mounted in a left heart simulator. Neochordae (expanded polytetrafluoroethylene) originated from either a simulated left ventricular apex, papillary muscle base, or papillary muscle tip location. The neochordae were attached at three sites along the P₂ leaflet segment: P_2Lateral; P_2Center, and P_2Medial. Mitral regurgitation was induced by cutting posterior leaflet P₂ marginal chordae. The forces on each neochord required to restore normal mitral valve coaptation were quantified for different ventricular anchoring origins and leaflet insertion sites.

Evaluation: The results showed that under both normotensive and hypertensive conditions, the force exerted was much higher at P_2Center than either P_2Lateral or P_2Medial, independent of ventricular anchor location. Also, forces on both P_2Lateral and P_2Medial were not statistically different.

Conclusions: Artificial neochordae treatment for all anchoring locations was effective in correcting induced mitral regurgitation. The P₂ central neochordae had a significantly higher force than both lateral neochords under all conditions.