Development of implantable medical devices: from an engineering perspective

Abstract

From the first pacemaker implant in 1958, numerous engineering and medical activities for implantable medical device development have faced challenges in materials, battery power, functionality, electrical power consumption, size shrinkage, system delivery, and wireless communication. With explosive advances in scientific and engineering technology, many implantable medical devices such as the pacemaker, cochlear implant, and real-time blood pressure sensors have been developed and improved. This trend of progress in medical devices will continue because of the coming super-aged society, which will result in more consumers for the devices. The inner body is a special space filled with electrical, chemical, mechanical, and marine-salted reactions. Therefore, electrical connectivity and communication, corrosion, robustness, and hermeticity are key factors to be considered during the development stage. The main participants in the development stage are the user, the medical staff, and the engineer or technician. Thus, there are three different viewpoints in the development of implantable devices. In this review paper, considerations in the development of implantable medical devices will be presented from the viewpoint of an engineering mind.

Keywords: Biocompatible materials; Biomedical engineering; Medical electronics; Micro-electro-mechanical systems.

Fig. 1

Material-dependent permeability. The graph shows also permeability as a function of thickness.

Fig. 2

Implantable blood pressure sensor. (A) Surgically implanted blood pressure sensor with a cuff-type design. The sensor is installed on the blood vessel directly. (B) Cardiomems implantable blood pressure sensor. The sensor is paced in the target position by use of a delivery system. The sensor is delivered by the same procedure with a stent.