Innovations in cardiac implantable electronic devices and post-market surveillance

This thesis focuses on innovation and post-market surveillance of cardiac electronic devices for the treatment of slow and fast heart rhythms in patients. Part I describes the use of the first leadless pacemakers in the Netherlands. A serious issue with the Nanostim was that the battery had a chance of premature failure. The company that produces the Nanostim issued a so-called Field Safety Notification (FSN) in response, stating that there is a 0.5% chance of failure. However, our main finding during longer observation showed a considerably higher failure rate, namely 37%. Part II describes the experiences with transvenous and subcutaneous ICDs in patients in the Netherlands. The experiences with 3,993 Linox leads in four large centers in the Netherlands are described. Our study shows that a significant number of patients (10.6%) experienced lead defects, which can have important negative consequences. In particular, detection of ‘noise’ can have serious consequences for patients resulting in inappropriate shocks. Moreover, the performance of an alternative ICD system, the S-ICD, in a typical ICD patient population is described. After that it delves further into the S-ICD, presenting a proof-of-concept study that introduces a second coil to influence the defibrillation threshold. In conclusion unbiased data from non-industry-related studies of good scientific quality is crucial. These types of studies should have an essential role for a robust post-market surveillance system. Besides, proof of concept studies are crucial to introduce new concepts and solutions in improving device technology.