An Implantable Sensor for Arterial Pressure Monitoring with Minimal Loading: Design and Finite Element Validation

This paper presents an in-vivo flexible pressure sensor that can be implanted around an artery for continuous measurement of blood pressure. Currently, in-vivo arterial sensor architectures rely on circular geometries fully encasing the artery perimeter, leading to significant reduction in blood pressure and flow rate inside the artery. The novelty of the sensor presented here lies in its geometrical structure and application that minimizes such disadvantages. The design consists of two arc-shaped flexible piezoelectric sensors located across each other and fixed together using medical-grade sutures on an artery periphery. Radial expansion of the artery during blood pulse wave is converted to an electrical signal through piezoelectric transduction. Finite element simulations were performed on laminar flow and solid mechanics domains to evaluate the effect of sensor presence on blood pressure and flow. Compared to previously reported sensor designs, it has been demonstrated that the pressure and flow values can be raised from 95% to 98% and from 66% to 88%, respectively. The improvement in flow rate is specifically important and vital for heart- and organ implantation-related medical operations.