Henk Mulder

Comparison of longevity, pacing, and sensing characteristics of steroid-eluting epicardial versus conventional endocardial pacing leads in children

OBJECTIVE Because of either cardiac anatomy or small size, pacing in children often occurs by means of epicardial leads. The disadvantage of epicardial leads is the shorter longevity of these leads compared with endocardial leads. During short-term follow-up, improved stimulation thresholds were found for the newer steroid-eluting epicardial leads. The longevity of these leads may be better than that of conventional epicardial leads. An improved longevity of epicardial leads may influence the choice to either epicardial or endocardial pacing in children. METHODS We studied the longevity and the pacing and sensing characteristics of 33 steroid-eluting epicardial pacing leads (group I, 15 atrial, 18 ventricular) implanted between November 1991 and October 1996 in 20 children with a mean age of 7.6 +/- 6.5 years (mean +/- SD), and 29 endocardial pacing leads (group II, 15 atrial, 14 ventricular) implanted during the same period in 21 children with a mean age of 11.7 +/- 4.7 years. RESULTS The mean follow-up in group I was 2.9 +/- 1.6 years and in group II 3.1 +/- 1.7 years (P =.61). The 2-year survival of the leads in group I was 91% +/- 5% and in group II 86% +/- 7% (P =.97). Lead failure occurred in both groups in 4 leads (P =.85). Chronic stimulation and sensing thresholds were similar. CONCLUSIONS Steroid-eluting epicardial leads have the same longevity as the conventional endocardial leads. Pacing and sensing thresholds were similar and did not change during follow-up. Therefore steroid-eluting epicardial pacing leads are a good alternative for endocardial leads in small children and in children with congenital heart disease.

The State of Science Communication Programs at Universities Around the World

Building on discussions at two workshops held at the recent 10th International Conference on the Public Communication of Science and Technology during June 2008 in Malmö, Sweden, this article proposes specific steps toward achieving a common understanding of the essential elements for academic programs in science communication. About 40 academics, science communication professionals, and students from at least 16 countries participated in this process.

Analysis of atrial sensed far-field ventricular signals: A reassessment

Accurate detection of the spontaneous far‐field ventricular signal may be used to determine the ventricular activation, and hence, the interval from atrial stimulus to the ventricular R wave (AR interval) using a standard atrial pacing lead. This can be useful in developing a physiological atrial rate responsive (AAIR) pacemaker and in further improving DDD(R) pacing algorithms. In order to better characterize the atrial sensed far‐field ventricular signal, 200 consecutive patients undergoing pacemaker implantation were studied. The amplitude of the far‐field ventricular signal was significantly smaller than that of the atrial deflection. In all recordings, the slew rate of the atrial deflection was larger than that of the far‐field ventricular signal. Subdivision of the recordings by electrode position, pocket location, or QRS duration on the surface ECG resulted in significantly different signal characteristics. The amplitude and slew rate of the far‐field ventricular signal were significantly smaller in bipolar versus unipolar sensing. Atrial sensed far‐field ventricular recordings could also be obtained in the case of ventricular pacing. Our results indicate that accurate sensing of the far‐field ventricular signal from an atrial pacing lead is conceivable in most patients. The different signal characteristics in relation to parameters, such as electrode position, sensing mode, and pocket location, may be useful in determining the optimal conditions for signal sensing.

Maximizing the Policy Impacts of Public Engagement: A European Study

There is a lack of published evidence which demonstrates the impacts of public engagement (PE) in science and technology policy. This might represent the failure of PE to achieve policy impacts or indicate a lack of effective procedures for discerning the uptake by policy makers of PE-derived outputs. While efforts have been made to identify and categorize different types of policy impact, research has rarely attempted to link policy impact with PE procedures, political procedures, or the connections between them. In this article, we propose a simple conceptual model to capture this information, based on semistructured interviews with both policy makers and PE practitioners. A range of criteria are identified to increase the policy impact of PE. The role of PE practitioners in realizing impacts through their interactions with policy makers in the informal “in-between” spaces of public engagement is emphasized. However, the potential contradictions between the pursuit of policy impacts and the more traditional conceptualizations of PE effectiveness are discussed. The main barrier to the identification of policy impacts from PE may lie within policy processes themselves. Political institutions have responsibility to establish formalized procedures for monitoring the uptake and use of evidence from PE in their decision-making processes.

Upstream Public Engagement in Nanotechnology: Constraints and Opportunities

Upstream public engagement with new science and technology is considered important but challenging. This article shows how engagement events are embedded in broader institutional and cultural contexts. By studying two different cases of upstream engagement in nanotechnology, we demonstrate how existing institutional responsibilities and cultural repertoires contribute much to the productivity of actual engagement events. Insight into these wider world dynamics will help science communicators (or event organizers) foster reflection and deliberation among relevant actors about whether and how upstream public engagement can have an impact on the governance of new science and technology.

Remodel, a game for strategic issues in industrial R&D and production planning

This chapter describes the game `Remodel’. It has been developed in the Netherlands. It focuses on strategic decisions in regard to technological innovation and environmental regulation. The game stimulates the awareness of science and engineering students for the organisational and political context of their future professions.