Enhanced Fatigue Performance of VAR/EBR Nitinol for Transcatheter Heart Valve Applications: Material Characterization and Design Implications.

Abstract

Transcatheter cardiovascular devices require high-purity Nitinol materials with exceptional fatigue resistance to meet stringent Class III regulatory durability requirements. Ultra-clean VAR/EBR (Vacuum Arc Remelt/Electron Beam Remelt) Nitinol represents a metallurgical advancement that achieves unprecedented control over inclusion size and distribution. This study characterizes the fatigue behavior of VAR/EBR Nitinol with nominal inclusion sizes below 10 μm under conditions representative of tr