Mechanistic study of ventricular hook anchor for heart valve replacement or repair

Objective: The objective of this study was to investigate the mechanics of ventricular anchor for heart valve repair or replacement. Methods: Thirteen anchors were designed based on six geometric parameters of the anchor teeth: width, thickness, root length, radius of curvature, tip angle, and tip length. Finite element method was applied to simulate the process of the anchor compressing into a sheath. The Von-Mises strain, peak pulling force, and bite depth were evaluated. An experiment was performed to validate the simulation. Results: The maximum Von-Mises strain was at the contact region of the anchor in a sheath where the teeth were compressed against one another and were distorted. The maximum strain increased with an increase in tooth width, thickness, radius of curvature and tip angle. The peak pulling force increased as tooth thickness and width increased, and radius of curvature decreased. Both the radial and axial bite depths increased with an increase in the tip length at the tip length≥3 ​mm. The radial bite depth increased with an increase in the radius of curvature. Conclusion: 1) the maximum strain depends primarily on the tooth width, thickness, radius of curvature and tip angle; 2) the peak pulling force depends primarily on the tooth width, thickness, radius of curvature; 3) the axial bite depth depends primarily on the tip length at the tip length≥3 ​mm. The radial bite depth depends on the radius of curvature and the tip length at the tip length >3 ​mm. The study provides guidance for ventricular anchor design.