Advancements in Shape Memory Implantable Medical Devices

Abstract Recent advances in bioelectronics, power supply miniaturization, and targeted energy delivery are enabling a new generation of true in vivo shape memory implantable devices that go beyond the self-expanding superelastic implants that have dominated the field for three decades. The central challenge—human tissue damage at temperatures achievable in relatively short durations—has historically limited the clinical use of Nitinol's shape memory properties, since common binary Nitinol alloys require temperatures up to 90°C for full actuation. This article reviews three devices currently under development that demonstrate viable approaches to safe in vivo actuation: Myra Vision's CalibrEye glaucoma shunt, the V-Wave Magical interatrial shunt, and Adona Medical's Delphi shunt. The recent innovations represented by these examples may signal an inflection point analogous to the early development of superelastic stents, with particularly promising opportunities in pediatric devices where implant sizing must adapt as patients grow.