Stimulation Electrodes for Pacemaker Applications

People suffering from certain types of arrhythmia §may benefit from the implantation of a cardiac §pacemaker. The electrical stimulation pulses are §transferred from the pacemaker to the heart via an §electrode which is implanted into the cardiac §tissue. To design functional pacemaker electrodes it §is essential to understand and control the charge §transferring processes on the electrode/tissue §interface. Bioelectrodes which operates outside its §inherent physical limits may degrade by §electrochemically driven processes (corrosion) or §produce chemical byproducts which may be harmful to §the patient. As the electrode size is reduced to §meet market demand the design strategies for high §performance stimulation and sensing bioelectrodes §needs to be revisited and the electrode/tissue §interface must be characterized to ensure safe and §optimal electrode performance during its operational §lifespan.§§In this thesis various electrochemical and surface §analytical techniques were used to investigate the §performance of different electrode materials and §surface textures.