Investigation of Retrieved Cardiac Devices

Damage assessment of lead and pulse generator with various exposure times is important in the development of cardiac devices. Approximately, 92.1 million patients in the US suffer from cardiovascular diseases with an estimated healthcare cost of over $300 billion and at least one million with implantable cardiac devices. These devices are complex and composed on multiple levels and present challenges while assessing the damage. However, the study on the analysis of cardiac devices may lend insight into common damage patterns and improve future cardiac devices design. The objective of this work is to perform a thorough in vivo damage assessment of retrieved 65 cardiac devices and 136 leads from different manufacturers (Medtronic, St. Jude Medical-Abbott and Boston Scientific). The examined damage features were surface deformation, burnishing, pitting, scratching, discoloration, delamination, insulation defects, coil damage, and abrasion. Methods to collect and compile data were performed, and statistical models were used to assess the sensitivity of measured parameters with in vivo performance. The devices from Medtronic and Boston Scientific were affected by the damage modes but these damages could not have affected the functionality of the devices and the therapy. The main damage mode observed was scratching, and the anterior side was more exposed to damage than the posterior side. Medtronic leads showed significant resistant to different damage modes when compared to Boston Scientific and St. Jude Medical, and the middle part was more exposed to damage than the proximal part. Medtronic leads showed failure rates lower than other manufacturers based on the 65 devices that were examined in this paper.